diff options
Diffstat (limited to 'plugins/AdvaImg/src/LibPNG/png.c')
| -rw-r--r-- | plugins/AdvaImg/src/LibPNG/png.c | 2194 |
1 files changed, 1809 insertions, 385 deletions
diff --git a/plugins/AdvaImg/src/LibPNG/png.c b/plugins/AdvaImg/src/LibPNG/png.c index 55fbc8fcc1..40db183bca 100644 --- a/plugins/AdvaImg/src/LibPNG/png.c +++ b/plugins/AdvaImg/src/LibPNG/png.c @@ -1,8 +1,8 @@ /* png.c - location for general purpose libpng functions
*
- * Last changed in libpng 1.5.11 [June 14, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.2 [April 25, 2013]
+ * Copyright (c) 1998-2013 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*
@@ -14,7 +14,7 @@ #include "pngpriv.h"
/* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_5_13 Your_png_h_is_not_version_1_5_13;
+typedef png_libpng_version_1_6_3 Your_png_h_is_not_version_1_6_3;
/* Tells libpng that we have already handled the first "num_bytes" bytes
* of the PNG file signature. If the PNG data is embedded into another
@@ -24,7 +24,7 @@ typedef png_libpng_version_1_5_13 Your_png_h_is_not_version_1_5_13; #ifdef PNG_READ_SUPPORTED
void PNGAPI
-png_set_sig_bytes(png_structp png_ptr, int num_bytes)
+png_set_sig_bytes(png_structrp png_ptr, int num_bytes)
{
png_debug(1, "in png_set_sig_bytes");
@@ -62,7 +62,7 @@ png_sig_cmp(png_const_bytep sig, png_size_t start, png_size_t num_to_check) if (start + num_to_check > 8)
num_to_check = 8 - start;
- return ((int)(png_memcmp(&sig[start], &png_signature[start], num_to_check)));
+ return ((int)(memcmp(&sig[start], &png_signature[start], num_to_check)));
}
#endif /* PNG_READ_SUPPORTED */
@@ -72,40 +72,34 @@ png_sig_cmp(png_const_bytep sig, png_size_t start, png_size_t num_to_check) PNG_FUNCTION(voidpf /* PRIVATE */,
png_zalloc,(voidpf png_ptr, uInt items, uInt size),PNG_ALLOCATED)
{
- png_voidp ptr;
- png_structp p=(png_structp)png_ptr;
- png_uint_32 save_flags=p->flags;
- png_alloc_size_t num_bytes;
+ png_alloc_size_t num_bytes = size;
if (png_ptr == NULL)
- return (NULL);
+ return NULL;
- if (items > PNG_UINT_32_MAX/size)
+ if (items >= (~(png_alloc_size_t)0)/size)
{
- png_warning (p, "Potential overflow in png_zalloc()");
- return (NULL);
+ png_warning (png_voidcast(png_structrp, png_ptr),
+ "Potential overflow in png_zalloc()");
+ return NULL;
}
- num_bytes = (png_alloc_size_t)items * size;
-
- p->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
- ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes);
- p->flags=save_flags;
- return ((voidpf)ptr);
+ num_bytes *= items;
+ return png_malloc_warn(png_voidcast(png_structrp, png_ptr), num_bytes);
}
/* Function to free memory for zlib */
void /* PRIVATE */
png_zfree(voidpf png_ptr, voidpf ptr)
{
- png_free((png_structp)png_ptr, (png_voidp)ptr);
+ png_free(png_voidcast(png_const_structrp,png_ptr), ptr);
}
/* Reset the CRC variable to 32 bits of 1's. Care must be taken
* in case CRC is > 32 bits to leave the top bits 0.
*/
void /* PRIVATE */
-png_reset_crc(png_structp png_ptr)
+png_reset_crc(png_structrp png_ptr)
{
/* The cast is safe because the crc is a 32 bit value. */
png_ptr->crc = (png_uint_32)crc32(0, Z_NULL, 0);
@@ -117,11 +111,11 @@ png_reset_crc(png_structp png_ptr) * trouble of calculating it.
*/
void /* PRIVATE */
-png_calculate_crc(png_structp png_ptr, png_const_bytep ptr, png_size_t length)
+png_calculate_crc(png_structrp png_ptr, png_const_bytep ptr, png_size_t length)
{
int need_crc = 1;
- if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name))
+ if (PNG_CHUNK_ANCILLARY(png_ptr->chunk_name))
{
if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
(PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
@@ -134,10 +128,10 @@ png_calculate_crc(png_structp png_ptr, png_const_bytep ptr, png_size_t length) need_crc = 0;
}
- /* 'uLong' is defined as unsigned long, this means that on some systems it is
- * a 64 bit value. crc32, however, returns 32 bits so the following cast is
- * safe. 'uInt' may be no more than 16 bits, so it is necessary to perform a
- * loop here.
+ /* 'uLong' is defined in zlib.h as unsigned long; this means that on some
+ * systems it is a 64 bit value. crc32, however, returns 32 bits so the
+ * following cast is safe. 'uInt' may be no more than 16 bits, so it is
+ * necessary to perform a loop here.
*/
if (need_crc && length > 0)
{
@@ -145,18 +139,18 @@ png_calculate_crc(png_structp png_ptr, png_const_bytep ptr, png_size_t length) do
{
- uInt safeLength = (uInt)length;
- if (safeLength == 0)
- safeLength = (uInt)-1; /* evil, but safe */
+ uInt safe_length = (uInt)length;
+ if (safe_length == 0)
+ safe_length = (uInt)-1; /* evil, but safe */
- crc = crc32(crc, ptr, safeLength);
+ crc = crc32(crc, ptr, safe_length);
- /* The following should never issue compiler warnings, if they do the
+ /* The following should never issue compiler warnings; if they do the
* target system has characteristics that will probably violate other
* assumptions within the libpng code.
*/
- ptr += safeLength;
- length -= safeLength;
+ ptr += safe_length;
+ length -= safe_length;
}
while (length > 0);
@@ -166,10 +160,10 @@ png_calculate_crc(png_structp png_ptr, png_const_bytep ptr, png_size_t length) }
/* Check a user supplied version number, called from both read and write
- * functions that create a png_struct
+ * functions that create a png_struct.
*/
int
-png_user_version_check(png_structp png_ptr, png_const_charp user_png_ver)
+png_user_version_check(png_structrp png_ptr, png_const_charp user_png_ver)
{
if (user_png_ver)
{
@@ -190,20 +184,23 @@ png_user_version_check(png_structp png_ptr, png_const_charp user_png_ver) /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
* we must recompile any applications that use any older library version.
* For versions after libpng 1.0, we will be compatible, so we need
- * only check the first digit.
+ * only check the first and third digits (note that when we reach version
+ * 1.10 we will need to check the fourth symbol, namely user_png_ver[3]).
*/
if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
- (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
+ (user_png_ver[0] == '1' && (user_png_ver[2] != png_libpng_ver[2] ||
+ user_png_ver[3] != png_libpng_ver[3])) ||
(user_png_ver[0] == '0' && user_png_ver[2] < '9'))
{
#ifdef PNG_WARNINGS_SUPPORTED
size_t pos = 0;
char m[128];
- pos = png_safecat(m, sizeof m, pos, "Application built with libpng-");
- pos = png_safecat(m, sizeof m, pos, user_png_ver);
- pos = png_safecat(m, sizeof m, pos, " but running with ");
- pos = png_safecat(m, sizeof m, pos, png_libpng_ver);
+ pos = png_safecat(m, (sizeof m), pos,
+ "Application built with libpng-");
+ pos = png_safecat(m, (sizeof m), pos, user_png_ver);
+ pos = png_safecat(m, (sizeof m), pos, " but running with ");
+ pos = png_safecat(m, (sizeof m), pos, png_libpng_ver);
png_warning(png_ptr, m);
#endif
@@ -220,43 +217,145 @@ png_user_version_check(png_structp png_ptr, png_const_charp user_png_ver) return 1;
}
-/* Allocate the memory for an info_struct for the application. We don't
- * really need the png_ptr, but it could potentially be useful in the
- * future. This should be used in favour of malloc(png_sizeof(png_info))
- * and png_info_init() so that applications that want to use a shared
- * libpng don't have to be recompiled if png_info changes size.
+/* Generic function to create a png_struct for either read or write - this
+ * contains the common initialization.
*/
+PNG_FUNCTION(png_structp /* PRIVATE */,
+png_create_png_struct,(png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+ png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED)
+{
+ png_struct create_struct;
+# ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf create_jmp_buf;
+# endif
+
+ /* This temporary stack-allocated structure is used to provide a place to
+ * build enough context to allow the user provided memory allocator (if any)
+ * to be called.
+ */
+ memset(&create_struct, 0, (sizeof create_struct));
+
+ /* Added at libpng-1.2.6 */
+# ifdef PNG_USER_LIMITS_SUPPORTED
+ create_struct.user_width_max = PNG_USER_WIDTH_MAX;
+ create_struct.user_height_max = PNG_USER_HEIGHT_MAX;
+
+# ifdef PNG_USER_CHUNK_CACHE_MAX
+ /* Added at libpng-1.2.43 and 1.4.0 */
+ create_struct.user_chunk_cache_max = PNG_USER_CHUNK_CACHE_MAX;
+# endif
+
+# ifdef PNG_USER_CHUNK_MALLOC_MAX
+ /* Added at libpng-1.2.43 and 1.4.1, required only for read but exists
+ * in png_struct regardless.
+ */
+ create_struct.user_chunk_malloc_max = PNG_USER_CHUNK_MALLOC_MAX;
+# endif
+# endif
+
+ /* The following two API calls simply set fields in png_struct, so it is safe
+ * to do them now even though error handling is not yet set up.
+ */
+# ifdef PNG_USER_MEM_SUPPORTED
+ png_set_mem_fn(&create_struct, mem_ptr, malloc_fn, free_fn);
+# endif
+
+ /* (*error_fn) can return control to the caller after the error_ptr is set,
+ * this will result in a memory leak unless the error_fn does something
+ * extremely sophisticated. The design lacks merit but is implicit in the
+ * API.
+ */
+ png_set_error_fn(&create_struct, error_ptr, error_fn, warn_fn);
+
+# ifdef PNG_SETJMP_SUPPORTED
+ if (!setjmp(create_jmp_buf))
+ {
+ /* Temporarily fake out the longjmp information until we have
+ * successfully completed this function. This only works if we have
+ * setjmp() support compiled in, but it is safe - this stuff should
+ * never happen.
+ */
+ create_struct.jmp_buf_ptr = &create_jmp_buf;
+ create_struct.jmp_buf_size = 0; /*stack allocation*/
+ create_struct.longjmp_fn = longjmp;
+# else
+ {
+# endif
+ /* Call the general version checker (shared with read and write code):
+ */
+ if (png_user_version_check(&create_struct, user_png_ver))
+ {
+ png_structrp png_ptr = png_voidcast(png_structrp,
+ png_malloc_warn(&create_struct, (sizeof *png_ptr)));
+
+ if (png_ptr != NULL)
+ {
+ /* png_ptr->zstream holds a back-pointer to the png_struct, so
+ * this can only be done now:
+ */
+ create_struct.zstream.zalloc = png_zalloc;
+ create_struct.zstream.zfree = png_zfree;
+ create_struct.zstream.opaque = png_ptr;
+
+# ifdef PNG_SETJMP_SUPPORTED
+ /* Eliminate the local error handling: */
+ create_struct.jmp_buf_ptr = NULL;
+ create_struct.jmp_buf_size = 0;
+ create_struct.longjmp_fn = 0;
+# endif
+
+ *png_ptr = create_struct;
+
+ /* This is the successful return point */
+ return png_ptr;
+ }
+ }
+ }
+
+ /* A longjmp because of a bug in the application storage allocator or a
+ * simple failure to allocate the png_struct.
+ */
+ return NULL;
+}
+
+/* Allocate the memory for an info_struct for the application. */
PNG_FUNCTION(png_infop,PNGAPI
-png_create_info_struct,(png_structp png_ptr),PNG_ALLOCATED)
+png_create_info_struct,(png_const_structrp png_ptr),PNG_ALLOCATED)
{
- png_infop info_ptr;
+ png_inforp info_ptr;
png_debug(1, "in png_create_info_struct");
if (png_ptr == NULL)
- return (NULL);
+ return NULL;
+
+ /* Use the internal API that does not (or at least should not) error out, so
+ * that this call always returns ok. The application typically sets up the
+ * error handling *after* creating the info_struct because this is the way it
+ * has always been done in 'example.c'.
+ */
+ info_ptr = png_voidcast(png_inforp, png_malloc_base(png_ptr,
+ (sizeof *info_ptr)));
-#ifdef PNG_USER_MEM_SUPPORTED
- info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
- png_ptr->malloc_fn, png_ptr->mem_ptr);
-#else
- info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
-#endif
if (info_ptr != NULL)
- png_info_init_3(&info_ptr, png_sizeof(png_info));
+ memset(info_ptr, 0, (sizeof *info_ptr));
- return (info_ptr);
+ return info_ptr;
}
/* This function frees the memory associated with a single info struct.
* Normally, one would use either png_destroy_read_struct() or
* png_destroy_write_struct() to free an info struct, but this may be
- * useful for some applications.
+ * useful for some applications. From libpng 1.6.0 this function is also used
+ * internally to implement the png_info release part of the 'struct' destroy
+ * APIs. This ensures that all possible approaches free the same data (all of
+ * it).
*/
void PNGAPI
-png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr)
+png_destroy_info_struct(png_const_structrp png_ptr, png_infopp info_ptr_ptr)
{
- png_infop info_ptr = NULL;
+ png_inforp info_ptr = NULL;
png_debug(1, "in png_destroy_info_struct");
@@ -268,46 +367,57 @@ png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr) if (info_ptr != NULL)
{
- png_info_destroy(png_ptr, info_ptr);
-
-#ifdef PNG_USER_MEM_SUPPORTED
- png_destroy_struct_2((png_voidp)info_ptr, png_ptr->free_fn,
- png_ptr->mem_ptr);
-#else
- png_destroy_struct((png_voidp)info_ptr);
-#endif
+ /* Do this first in case of an error below; if the app implements its own
+ * memory management this can lead to png_free calling png_error, which
+ * will abort this routine and return control to the app error handler.
+ * An infinite loop may result if it then tries to free the same info
+ * ptr.
+ */
*info_ptr_ptr = NULL;
+
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
+ memset(info_ptr, 0, (sizeof *info_ptr));
+ png_free(png_ptr, info_ptr);
}
}
/* Initialize the info structure. This is now an internal function (0.89)
* and applications using it are urged to use png_create_info_struct()
- * instead.
+ * instead. Use deprecated in 1.6.0, internal use removed (used internally it
+ * is just a memset).
+ *
+ * NOTE: it is almost inconceivable that this API is used because it bypasses
+ * the user-memory mechanism and the user error handling/warning mechanisms in
+ * those cases where it does anything other than a memset.
*/
-
-void PNGAPI
-png_info_init_3(png_infopp ptr_ptr, png_size_t png_info_struct_size)
+PNG_FUNCTION(void,PNGAPI
+png_info_init_3,(png_infopp ptr_ptr, png_size_t png_info_struct_size),
+ PNG_DEPRECATED)
{
- png_infop info_ptr = *ptr_ptr;
+ png_inforp info_ptr = *ptr_ptr;
png_debug(1, "in png_info_init_3");
if (info_ptr == NULL)
return;
- if (png_sizeof(png_info) > png_info_struct_size)
+ if ((sizeof (png_info)) > png_info_struct_size)
{
- png_destroy_struct(info_ptr);
- info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
+ *ptr_ptr = NULL;
+ /* The following line is why this API should not be used: */
+ free(info_ptr);
+ info_ptr = png_voidcast(png_inforp, png_malloc_base(NULL,
+ (sizeof *info_ptr)));
*ptr_ptr = info_ptr;
}
/* Set everything to 0 */
- png_memset(info_ptr, 0, png_sizeof(png_info));
+ memset(info_ptr, 0, (sizeof *info_ptr));
}
+/* The following API is not called internally */
void PNGAPI
-png_data_freer(png_structp png_ptr, png_infop info_ptr,
+png_data_freer(png_const_structrp png_ptr, png_inforp info_ptr,
int freer, png_uint_32 mask)
{
png_debug(1, "in png_data_freer");
@@ -322,12 +432,11 @@ png_data_freer(png_structp png_ptr, png_infop info_ptr, info_ptr->free_me &= ~mask;
else
- png_warning(png_ptr,
- "Unknown freer parameter in png_data_freer");
+ png_error(png_ptr, "Unknown freer parameter in png_data_freer");
}
void PNGAPI
-png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask,
+png_free_data(png_const_structrp png_ptr, png_inforp info_ptr, png_uint_32 mask,
int num)
{
png_debug(1, "in png_free_data");
@@ -392,8 +501,8 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, info_ptr->pcal_units = NULL;
if (info_ptr->pcal_params != NULL)
{
- int i;
- for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
+ unsigned int i;
+ for (i = 0; i < info_ptr->pcal_nparams; i++)
{
png_free(png_ptr, info_ptr->pcal_params[i]);
info_ptr->pcal_params[i] = NULL;
@@ -406,7 +515,7 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, #endif
#ifdef PNG_iCCP_SUPPORTED
- /* Free any iCCP entry */
+ /* Free any profile entry */
if ((mask & PNG_FREE_ICCP) & info_ptr->free_me)
{
png_free(png_ptr, info_ptr->iccp_name);
@@ -437,8 +546,8 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, if (info_ptr->splt_palettes_num)
{
int i;
- for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
- png_free_data(png_ptr, info_ptr, PNG_FREE_SPLT, i);
+ for (i = 0; i < info_ptr->splt_palettes_num; i++)
+ png_free_data(png_ptr, info_ptr, PNG_FREE_SPLT, (int)i);
png_free(png_ptr, info_ptr->splt_palettes);
info_ptr->splt_palettes = NULL;
@@ -449,13 +558,7 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, }
#endif
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
- if (png_ptr->unknown_chunk.data)
- {
- png_free(png_ptr, png_ptr->unknown_chunk.data);
- png_ptr->unknown_chunk.data = NULL;
- }
-
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
if ((mask & PNG_FREE_UNKN) & info_ptr->free_me)
{
if (num != -1)
@@ -474,7 +577,7 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, if (info_ptr->unknown_chunks_num)
{
for (i = 0; i < info_ptr->unknown_chunks_num; i++)
- png_free_data(png_ptr, info_ptr, PNG_FREE_UNKN, i);
+ png_free_data(png_ptr, info_ptr, PNG_FREE_UNKN, (int)i);
png_free(png_ptr, info_ptr->unknown_chunks);
info_ptr->unknown_chunks = NULL;
@@ -497,7 +600,7 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, /* Free any PLTE entry that was internally allocated */
if ((mask & PNG_FREE_PLTE) & info_ptr->free_me)
{
- png_zfree(png_ptr, info_ptr->palette);
+ png_free(png_ptr, info_ptr->palette);
info_ptr->palette = NULL;
info_ptr->valid &= ~PNG_INFO_PLTE;
info_ptr->num_palette = 0;
@@ -509,8 +612,8 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, {
if (info_ptr->row_pointers)
{
- int row;
- for (row = 0; row < (int)info_ptr->height; row++)
+ png_uint_32 row;
+ for (row = 0; row < info_ptr->height; row++)
{
png_free(png_ptr, info_ptr->row_pointers[row]);
info_ptr->row_pointers[row] = NULL;
@@ -527,29 +630,6 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, info_ptr->free_me &= ~mask;
}
-
-/* This is an internal routine to free any memory that the info struct is
- * pointing to before re-using it or freeing the struct itself. Recall
- * that png_free() checks for NULL pointers for us.
- */
-void /* PRIVATE */
-png_info_destroy(png_structp png_ptr, png_infop info_ptr)
-{
- png_debug(1, "in png_info_destroy");
-
- png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
- if (png_ptr->num_chunk_list)
- {
- png_free(png_ptr, png_ptr->chunk_list);
- png_ptr->chunk_list = NULL;
- png_ptr->num_chunk_list = 0;
- }
-#endif
-
- png_info_init_3(&info_ptr, png_sizeof(png_info));
-}
#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
/* This function returns a pointer to the io_ptr associated with the user
@@ -557,7 +637,7 @@ png_info_destroy(png_structp png_ptr, png_infop info_ptr) * pointer before png_write_destroy() or png_read_destroy() are called.
*/
png_voidp PNGAPI
-png_get_io_ptr(png_structp png_ptr)
+png_get_io_ptr(png_const_structrp png_ptr)
{
if (png_ptr == NULL)
return (NULL);
@@ -574,7 +654,7 @@ png_get_io_ptr(png_structp png_ptr) * function of your own because "FILE *" isn't necessarily available.
*/
void PNGAPI
-png_init_io(png_structp png_ptr, png_FILE_p fp)
+png_init_io(png_structrp png_ptr, png_FILE_p fp)
{
png_debug(1, "in png_init_io");
@@ -585,42 +665,52 @@ png_init_io(png_structp png_ptr, png_FILE_p fp) }
# endif
+#ifdef PNG_SAVE_INT_32_SUPPORTED
+/* The png_save_int_32 function assumes integers are stored in two's
+ * complement format. If this isn't the case, then this routine needs to
+ * be modified to write data in two's complement format. Note that,
+ * the following works correctly even if png_int_32 has more than 32 bits
+ * (compare the more complex code required on read for sign extension.)
+ */
+void PNGAPI
+png_save_int_32(png_bytep buf, png_int_32 i)
+{
+ buf[0] = (png_byte)((i >> 24) & 0xff);
+ buf[1] = (png_byte)((i >> 16) & 0xff);
+ buf[2] = (png_byte)((i >> 8) & 0xff);
+ buf[3] = (png_byte)(i & 0xff);
+}
+#endif
+
# ifdef PNG_TIME_RFC1123_SUPPORTED
/* Convert the supplied time into an RFC 1123 string suitable for use in
* a "Creation Time" or other text-based time string.
*/
-png_const_charp PNGAPI
-png_convert_to_rfc1123(png_structp png_ptr, png_const_timep ptime)
+int PNGAPI
+png_convert_to_rfc1123_buffer(char out[29], png_const_timep ptime)
{
static PNG_CONST char short_months[12][4] =
{"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
- if (png_ptr == NULL)
- return (NULL);
+ if (out == NULL)
+ return 0;
if (ptime->year > 9999 /* RFC1123 limitation */ ||
ptime->month == 0 || ptime->month > 12 ||
ptime->day == 0 || ptime->day > 31 ||
ptime->hour > 23 || ptime->minute > 59 ||
ptime->second > 60)
- {
- png_warning(png_ptr, "Ignoring invalid time value");
- return (NULL);
- }
+ return 0;
{
size_t pos = 0;
char number_buf[5]; /* enough for a four-digit year */
-# define APPEND_STRING(string)\
- pos = png_safecat(png_ptr->time_buffer, sizeof png_ptr->time_buffer,\
- pos, (string))
+# define APPEND_STRING(string) pos = png_safecat(out, 29, pos, (string))
# define APPEND_NUMBER(format, value)\
APPEND_STRING(PNG_FORMAT_NUMBER(number_buf, format, (value)))
-# define APPEND(ch)\
- if (pos < (sizeof png_ptr->time_buffer)-1)\
- png_ptr->time_buffer[pos++] = (ch)
+# define APPEND(ch) if (pos < 28) out[pos++] = (ch)
APPEND_NUMBER(PNG_NUMBER_FORMAT_u, (unsigned)ptime->day);
APPEND(' ');
@@ -640,14 +730,37 @@ png_convert_to_rfc1123(png_structp png_ptr, png_const_timep ptime) # undef APPEND_STRING
}
- return png_ptr->time_buffer;
+ return 1;
}
+
+# if PNG_LIBPNG_VER < 10700
+/* To do: remove the following from libpng-1.7 */
+/* Original API that uses a private buffer in png_struct.
+ * Deprecated because it causes png_struct to carry a spurious temporary
+ * buffer (png_struct::time_buffer), better to have the caller pass this in.
+ */
+png_const_charp PNGAPI
+png_convert_to_rfc1123(png_structrp png_ptr, png_const_timep ptime)
+{
+ if (png_ptr != NULL)
+ {
+ /* The only failure above if png_ptr != NULL is from an invalid ptime */
+ if (!png_convert_to_rfc1123_buffer(png_ptr->time_buffer, ptime))
+ png_warning(png_ptr, "Ignoring invalid time value");
+
+ else
+ return png_ptr->time_buffer;
+ }
+
+ return NULL;
+}
+# endif
# endif /* PNG_TIME_RFC1123_SUPPORTED */
#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
png_const_charp PNGAPI
-png_get_copyright(png_const_structp png_ptr)
+png_get_copyright(png_const_structrp png_ptr)
{
PNG_UNUSED(png_ptr) /* Silence compiler warning about unused png_ptr */
#ifdef PNG_STRING_COPYRIGHT
@@ -655,14 +768,14 @@ png_get_copyright(png_const_structp png_ptr) #else
# ifdef __STDC__
return PNG_STRING_NEWLINE \
- "libpng version 1.5.13 - September 27, 2012" PNG_STRING_NEWLINE \
- "Copyright (c) 1998-2012 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
+ "libpng version 1.6.3 - July 18, 2013" PNG_STRING_NEWLINE \
+ "Copyright (c) 1998-2013 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
"Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
"Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
PNG_STRING_NEWLINE;
# else
- return "libpng version 1.5.13 - September 27, 2012\
- Copyright (c) 1998-2012 Glenn Randers-Pehrson\
+ return "libpng version 1.6.3 - July 18, 2013\
+ Copyright (c) 1998-2013 Glenn Randers-Pehrson\
Copyright (c) 1996-1997 Andreas Dilger\
Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
# endif
@@ -678,14 +791,14 @@ png_get_copyright(png_const_structp png_ptr) * it is guaranteed that png.c uses the correct version of png.h.
*/
png_const_charp PNGAPI
-png_get_libpng_ver(png_const_structp png_ptr)
+png_get_libpng_ver(png_const_structrp png_ptr)
{
/* Version of *.c files used when building libpng */
return png_get_header_ver(png_ptr);
}
png_const_charp PNGAPI
-png_get_header_ver(png_const_structp png_ptr)
+png_get_header_ver(png_const_structrp png_ptr)
{
/* Version of *.h files used when building libpng */
PNG_UNUSED(png_ptr) /* Silence compiler warning about unused png_ptr */
@@ -693,7 +806,7 @@ png_get_header_ver(png_const_structp png_ptr) }
png_const_charp PNGAPI
-png_get_header_version(png_const_structp png_ptr)
+png_get_header_version(png_const_structrp png_ptr)
{
/* Returns longer string containing both version and date */
PNG_UNUSED(png_ptr) /* Silence compiler warning about unused png_ptr */
@@ -708,52 +821,61 @@ png_get_header_version(png_const_structp png_ptr) #endif
}
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
int PNGAPI
-png_handle_as_unknown(png_structp png_ptr, png_const_bytep chunk_name)
+png_handle_as_unknown(png_const_structrp png_ptr, png_const_bytep chunk_name)
{
/* Check chunk_name and return "keep" value if it's on the list, else 0 */
png_const_bytep p, p_end;
- if (png_ptr == NULL || chunk_name == NULL || png_ptr->num_chunk_list <= 0)
+ if (png_ptr == NULL || chunk_name == NULL || png_ptr->num_chunk_list == 0)
return PNG_HANDLE_CHUNK_AS_DEFAULT;
p_end = png_ptr->chunk_list;
p = p_end + png_ptr->num_chunk_list*5; /* beyond end */
/* The code is the fifth byte after each four byte string. Historically this
- * code was always searched from the end of the list, so it should continue
- * to do so in case there are duplicated entries.
+ * code was always searched from the end of the list, this is no longer
+ * necessary because the 'set' routine handles duplicate entries correcty.
*/
do /* num_chunk_list > 0, so at least one */
{
p -= 5;
- if (!png_memcmp(chunk_name, p, 4))
+
+ if (!memcmp(chunk_name, p, 4))
return p[4];
}
while (p > p_end);
+ /* This means that known chunks should be processed and unknown chunks should
+ * be handled according to the value of png_ptr->unknown_default; this can be
+ * confusing because, as a result, there are two levels of defaulting for
+ * unknown chunks.
+ */
return PNG_HANDLE_CHUNK_AS_DEFAULT;
}
+#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
int /* PRIVATE */
-png_chunk_unknown_handling(png_structp png_ptr, png_uint_32 chunk_name)
+png_chunk_unknown_handling(png_const_structrp png_ptr, png_uint_32 chunk_name)
{
png_byte chunk_string[5];
PNG_CSTRING_FROM_CHUNK(chunk_string, chunk_name);
return png_handle_as_unknown(png_ptr, chunk_string);
}
-#endif
+#endif /* READ_UNKNOWN_CHUNKS */
+#endif /* SET_UNKNOWN_CHUNKS */
#ifdef PNG_READ_SUPPORTED
/* This function, added to libpng-1.0.6g, is untested. */
int PNGAPI
-png_reset_zstream(png_structp png_ptr)
+png_reset_zstream(png_structrp png_ptr)
{
if (png_ptr == NULL)
return Z_STREAM_ERROR;
+ /* WARNING: this resets the window bits to the maximum! */
return (inflateReset(&png_ptr->zstream));
}
#endif /* PNG_READ_SUPPORTED */
@@ -769,114 +891,271 @@ png_access_version_number(void) #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+/* Ensure that png_ptr->zstream.msg holds some appropriate error message string.
+ * If it doesn't 'ret' is used to set it to something appropriate, even in cases
+ * like Z_OK or Z_STREAM_END where the error code is apparently a success code.
+ */
+void /* PRIVATE */
+png_zstream_error(png_structrp png_ptr, int ret)
+{
+ /* Translate 'ret' into an appropriate error string, priority is given to the
+ * one in zstream if set. This always returns a string, even in cases like
+ * Z_OK or Z_STREAM_END where the error code is a success code.
+ */
+ if (png_ptr->zstream.msg == NULL) switch (ret)
+ {
+ default:
+ case Z_OK:
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("unexpected zlib return code");
+ break;
+
+ case Z_STREAM_END:
+ /* Normal exit */
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("unexpected end of LZ stream");
+ break;
+
+ case Z_NEED_DICT:
+ /* This means the deflate stream did not have a dictionary; this
+ * indicates a bogus PNG.
+ */
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("missing LZ dictionary");
+ break;
+
+ case Z_ERRNO:
+ /* gz APIs only: should not happen */
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("zlib IO error");
+ break;
+
+ case Z_STREAM_ERROR:
+ /* internal libpng error */
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("bad parameters to zlib");
+ break;
+
+ case Z_DATA_ERROR:
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("damaged LZ stream");
+ break;
+
+ case Z_MEM_ERROR:
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("insufficient memory");
+ break;
+
+ case Z_BUF_ERROR:
+ /* End of input or output; not a problem if the caller is doing
+ * incremental read or write.
+ */
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("truncated");
+ break;
+
+ case Z_VERSION_ERROR:
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("unsupported zlib version");
+ break;
+
+ case PNG_UNEXPECTED_ZLIB_RETURN:
+ /* Compile errors here mean that zlib now uses the value co-opted in
+ * pngpriv.h for PNG_UNEXPECTED_ZLIB_RETURN; update the switch above
+ * and change pngpriv.h. Note that this message is "... return",
+ * whereas the default/Z_OK one is "... return code".
+ */
+ png_ptr->zstream.msg = PNGZ_MSG_CAST("unexpected zlib return");
+ break;
+ }
+}
+
/* png_convert_size: a PNGAPI but no longer in png.h, so deleted
* at libpng 1.5.5!
*/
/* Added at libpng version 1.2.34 and 1.4.0 (moved from pngset.c) */
-# ifdef PNG_CHECK_cHRM_SUPPORTED
-
-int /* PRIVATE */
-png_check_cHRM_fixed(png_structp png_ptr,
- png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
- png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
- png_fixed_point blue_x, png_fixed_point blue_y)
+#ifdef PNG_GAMMA_SUPPORTED /* always set if COLORSPACE */
+static int
+png_colorspace_check_gamma(png_const_structrp png_ptr,
+ png_colorspacerp colorspace, png_fixed_point gAMA, int from)
+ /* This is called to check a new gamma value against an existing one. The
+ * routine returns false if the new gamma value should not be written.
+ *
+ * 'from' says where the new gamma value comes from:
+ *
+ * 0: the new gamma value is the libpng estimate for an ICC profile
+ * 1: the new gamma value comes from a gAMA chunk
+ * 2: the new gamma value comes from an sRGB chunk
+ */
{
- int ret = 1;
- unsigned long xy_hi,xy_lo,yx_hi,yx_lo;
+ png_fixed_point gtest;
- png_debug(1, "in function png_check_cHRM_fixed");
+ if ((colorspace->flags & PNG_COLORSPACE_HAVE_GAMMA) != 0 &&
+ (!png_muldiv(>est, colorspace->gamma, PNG_FP_1, gAMA) ||
+ png_gamma_significant(gtest)))
+ {
+ /* Either this is an sRGB image, in which case the calculated gamma
+ * approximation should match, or this is an image with a profile and the
+ * value libpng calculates for the gamma of the profile does not match the
+ * value recorded in the file. The former, sRGB, case is an error, the
+ * latter is just a warning.
+ */
+ if ((colorspace->flags & PNG_COLORSPACE_FROM_sRGB) != 0 || from == 2)
+ {
+ png_chunk_report(png_ptr, "gamma value does not match sRGB",
+ PNG_CHUNK_ERROR);
+ /* Do not overwrite an sRGB value */
+ return from == 2;
+ }
- if (png_ptr == NULL)
- return 0;
+ else /* sRGB tag not involved */
+ {
+ png_chunk_report(png_ptr, "gamma value does not match libpng estimate",
+ PNG_CHUNK_WARNING);
+ return from == 1;
+ }
+ }
+
+ return 1;
+}
- /* (x,y,z) values are first limited to 0..100000 (PNG_FP_1), the white
- * y must also be greater than 0. To test for the upper limit calculate
- * (PNG_FP_1-y) - x must be <= to this for z to be >= 0 (and the expression
- * cannot overflow.) At this point we know x and y are >= 0 and (x+y) is
- * <= PNG_FP_1. The previous test on PNG_MAX_UINT_31 is removed because it
- * pointless (and it produces compiler warnings!)
+void /* PRIVATE */
+png_colorspace_set_gamma(png_const_structrp png_ptr,
+ png_colorspacerp colorspace, png_fixed_point gAMA)
+{
+ /* Changed in libpng-1.5.4 to limit the values to ensure overflow can't
+ * occur. Since the fixed point representation is assymetrical it is
+ * possible for 1/gamma to overflow the limit of 21474 and this means the
+ * gamma value must be at least 5/100000 and hence at most 20000.0. For
+ * safety the limits here are a little narrower. The values are 0.00016 to
+ * 6250.0, which are truly ridiculous gamma values (and will produce
+ * displays that are all black or all white.)
+ *
+ * In 1.6.0 this test replaces the ones in pngrutil.c, in the gAMA chunk
+ * handling code, which only required the value to be >0.
*/
- if (white_x < 0 || white_y <= 0 ||
- red_x < 0 || red_y < 0 ||
- green_x < 0 || green_y < 0 ||
- blue_x < 0 || blue_y < 0)
- {
- png_warning(png_ptr,
- "Ignoring attempt to set negative chromaticity value");
- ret = 0;
- }
- /* And (x+y) must be <= PNG_FP_1 (so z is >= 0) */
- if (white_x > PNG_FP_1 - white_y)
- {
- png_warning(png_ptr, "Invalid cHRM white point");
- ret = 0;
- }
+ png_const_charp errmsg;
+
+ if (gAMA < 16 || gAMA > 625000000)
+ errmsg = "gamma value out of range";
+
+# ifdef PNG_READ_gAMA_SUPPORTED
+ /* Allow the application to set the gamma value more than once */
+ else if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
+ (colorspace->flags & PNG_COLORSPACE_FROM_gAMA) != 0)
+ errmsg = "duplicate";
+# endif
+
+ /* Do nothing if the colorspace is already invalid */
+ else if (colorspace->flags & PNG_COLORSPACE_INVALID)
+ return;
- if (red_x > PNG_FP_1 - red_y)
+ else
{
- png_warning(png_ptr, "Invalid cHRM red point");
- ret = 0;
+ if (png_colorspace_check_gamma(png_ptr, colorspace, gAMA, 1/*from gAMA*/))
+ {
+ /* Store this gamma value. */
+ colorspace->gamma = gAMA;
+ colorspace->flags |=
+ (PNG_COLORSPACE_HAVE_GAMMA | PNG_COLORSPACE_FROM_gAMA);
+ }
+
+ /* At present if the check_gamma test fails the gamma of the colorspace is
+ * not updated however the colorspace is not invalidated. This
+ * corresponds to the case where the existing gamma comes from an sRGB
+ * chunk or profile. An error message has already been output.
+ */
+ return;
}
- if (green_x > PNG_FP_1 - green_y)
+ /* Error exit - errmsg has been set. */
+ colorspace->flags |= PNG_COLORSPACE_INVALID;
+ png_chunk_report(png_ptr, errmsg, PNG_CHUNK_WRITE_ERROR);
+}
+
+void /* PRIVATE */
+png_colorspace_sync_info(png_const_structrp png_ptr, png_inforp info_ptr)
+{
+ if (info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID)
{
- png_warning(png_ptr, "Invalid cHRM green point");
- ret = 0;
+ /* Everything is invalid */
+ info_ptr->valid &= ~(PNG_INFO_gAMA|PNG_INFO_cHRM|PNG_INFO_sRGB|
+ PNG_INFO_iCCP);
+
+# ifdef PNG_COLORSPACE_SUPPORTED
+ /* Clean up the iCCP profile now if it won't be used. */
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, -1/*not used*/);
+# else
+ PNG_UNUSED(png_ptr)
+# endif
}
- if (blue_x > PNG_FP_1 - blue_y)
+ else
{
- png_warning(png_ptr, "Invalid cHRM blue point");
- ret = 0;
- }
+# ifdef PNG_COLORSPACE_SUPPORTED
+ /* Leave the INFO_iCCP flag set if the pngset.c code has already set
+ * it; this allows a PNG to contain a profile which matches sRGB and
+ * yet still have that profile retrievable by the application.
+ */
+ if (info_ptr->colorspace.flags & PNG_COLORSPACE_MATCHES_sRGB)
+ info_ptr->valid |= PNG_INFO_sRGB;
- png_64bit_product(green_x - red_x, blue_y - red_y, &xy_hi, &xy_lo);
- png_64bit_product(green_y - red_y, blue_x - red_x, &yx_hi, &yx_lo);
+ else
+ info_ptr->valid &= ~PNG_INFO_sRGB;
- if (xy_hi == yx_hi && xy_lo == yx_lo)
- {
- png_warning(png_ptr,
- "Ignoring attempt to set cHRM RGB triangle with zero area");
- ret = 0;
+ if (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS)
+ info_ptr->valid |= PNG_INFO_cHRM;
+
+ else
+ info_ptr->valid &= ~PNG_INFO_cHRM;
+# endif
+
+ if (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA)
+ info_ptr->valid |= PNG_INFO_gAMA;
+
+ else
+ info_ptr->valid &= ~PNG_INFO_gAMA;
}
+}
+
+#ifdef PNG_READ_SUPPORTED
+void /* PRIVATE */
+png_colorspace_sync(png_const_structrp png_ptr, png_inforp info_ptr)
+{
+ if (info_ptr == NULL) /* reduce code size; check here not in the caller */
+ return;
- return ret;
+ info_ptr->colorspace = png_ptr->colorspace;
+ png_colorspace_sync_info(png_ptr, info_ptr);
}
-# endif /* PNG_CHECK_cHRM_SUPPORTED */
+#endif
+#endif
-#ifdef PNG_cHRM_SUPPORTED
+#ifdef PNG_COLORSPACE_SUPPORTED
/* Added at libpng-1.5.5 to support read and write of true CIEXYZ values for
* cHRM, as opposed to using chromaticities. These internal APIs return
* non-zero on a parameter error. The X, Y and Z values are required to be
* positive and less than 1.0.
*/
-int png_xy_from_XYZ(png_xy *xy, png_XYZ XYZ)
+static int
+png_xy_from_XYZ(png_xy *xy, const png_XYZ *XYZ)
{
png_int_32 d, dwhite, whiteX, whiteY;
- d = XYZ.redX + XYZ.redY + XYZ.redZ;
- if (!png_muldiv(&xy->redx, XYZ.redX, PNG_FP_1, d)) return 1;
- if (!png_muldiv(&xy->redy, XYZ.redY, PNG_FP_1, d)) return 1;
+ d = XYZ->red_X + XYZ->red_Y + XYZ->red_Z;
+ if (!png_muldiv(&xy->redx, XYZ->red_X, PNG_FP_1, d)) return 1;
+ if (!png_muldiv(&xy->redy, XYZ->red_Y, PNG_FP_1, d)) return 1;
dwhite = d;
- whiteX = XYZ.redX;
- whiteY = XYZ.redY;
+ whiteX = XYZ->red_X;
+ whiteY = XYZ->red_Y;
- d = XYZ.greenX + XYZ.greenY + XYZ.greenZ;
- if (!png_muldiv(&xy->greenx, XYZ.greenX, PNG_FP_1, d)) return 1;
- if (!png_muldiv(&xy->greeny, XYZ.greenY, PNG_FP_1, d)) return 1;
+ d = XYZ->green_X + XYZ->green_Y + XYZ->green_Z;
+ if (!png_muldiv(&xy->greenx, XYZ->green_X, PNG_FP_1, d)) return 1;
+ if (!png_muldiv(&xy->greeny, XYZ->green_Y, PNG_FP_1, d)) return 1;
dwhite += d;
- whiteX += XYZ.greenX;
- whiteY += XYZ.greenY;
+ whiteX += XYZ->green_X;
+ whiteY += XYZ->green_Y;
- d = XYZ.blueX + XYZ.blueY + XYZ.blueZ;
- if (!png_muldiv(&xy->bluex, XYZ.blueX, PNG_FP_1, d)) return 1;
- if (!png_muldiv(&xy->bluey, XYZ.blueY, PNG_FP_1, d)) return 1;
+ d = XYZ->blue_X + XYZ->blue_Y + XYZ->blue_Z;
+ if (!png_muldiv(&xy->bluex, XYZ->blue_X, PNG_FP_1, d)) return 1;
+ if (!png_muldiv(&xy->bluey, XYZ->blue_Y, PNG_FP_1, d)) return 1;
dwhite += d;
- whiteX += XYZ.blueX;
- whiteY += XYZ.blueY;
+ whiteX += XYZ->blue_X;
+ whiteY += XYZ->blue_Y;
- /* The reference white is simply the same of the end-point (X,Y,Z) vectors,
+ /* The reference white is simply the sum of the end-point (X,Y,Z) vectors,
* thus:
*/
if (!png_muldiv(&xy->whitex, whiteX, PNG_FP_1, dwhite)) return 1;
@@ -885,7 +1164,8 @@ int png_xy_from_XYZ(png_xy *xy, png_XYZ XYZ) return 0;
}
-int png_XYZ_from_xy(png_XYZ *XYZ, png_xy xy)
+static int
+png_XYZ_from_xy(png_XYZ *XYZ, const png_xy *xy)
{
png_fixed_point red_inverse, green_inverse, blue_scale;
png_fixed_point left, right, denominator;
@@ -894,14 +1174,14 @@ int png_XYZ_from_xy(png_XYZ *XYZ, png_xy xy) * have end points with 0 tristimulus values (these are impossible end
* points, but they are used to cover the possible colors.)
*/
- if (xy.redx < 0 || xy.redx > PNG_FP_1) return 1;
- if (xy.redy < 0 || xy.redy > PNG_FP_1-xy.redx) return 1;
- if (xy.greenx < 0 || xy.greenx > PNG_FP_1) return 1;
- if (xy.greeny < 0 || xy.greeny > PNG_FP_1-xy.greenx) return 1;
- if (xy.bluex < 0 || xy.bluex > PNG_FP_1) return 1;
- if (xy.bluey < 0 || xy.bluey > PNG_FP_1-xy.bluex) return 1;
- if (xy.whitex < 0 || xy.whitex > PNG_FP_1) return 1;
- if (xy.whitey < 0 || xy.whitey > PNG_FP_1-xy.whitex) return 1;
+ if (xy->redx < 0 || xy->redx > PNG_FP_1) return 1;
+ if (xy->redy < 0 || xy->redy > PNG_FP_1-xy->redx) return 1;
+ if (xy->greenx < 0 || xy->greenx > PNG_FP_1) return 1;
+ if (xy->greeny < 0 || xy->greeny > PNG_FP_1-xy->greenx) return 1;
+ if (xy->bluex < 0 || xy->bluex > PNG_FP_1) return 1;
+ if (xy->bluey < 0 || xy->bluey > PNG_FP_1-xy->bluex) return 1;
+ if (xy->whitex < 0 || xy->whitex > PNG_FP_1) return 1;
+ if (xy->whitey < 0 || xy->whitey > PNG_FP_1-xy->whitex) return 1;
/* The reverse calculation is more difficult because the original tristimulus
* value had 9 independent values (red,green,blue)x(X,Y,Z) however only 8
@@ -1082,91 +1362,1001 @@ int png_XYZ_from_xy(png_XYZ *XYZ, png_xy xy) /* By the argument, above overflow should be impossible here. The return
* value of 2 indicates an internal error to the caller.
*/
- if (!png_muldiv(&left, xy.greenx-xy.bluex, xy.redy - xy.bluey, 7)) return 2;
- if (!png_muldiv(&right, xy.greeny-xy.bluey, xy.redx - xy.bluex, 7)) return 2;
+ if (!png_muldiv(&left, xy->greenx-xy->bluex, xy->redy - xy->bluey, 7))
+ return 2;
+ if (!png_muldiv(&right, xy->greeny-xy->bluey, xy->redx - xy->bluex, 7))
+ return 2;
denominator = left - right;
/* Now find the red numerator. */
- if (!png_muldiv(&left, xy.greenx-xy.bluex, xy.whitey-xy.bluey, 7)) return 2;
- if (!png_muldiv(&right, xy.greeny-xy.bluey, xy.whitex-xy.bluex, 7)) return 2;
+ if (!png_muldiv(&left, xy->greenx-xy->bluex, xy->whitey-xy->bluey, 7))
+ return 2;
+ if (!png_muldiv(&right, xy->greeny-xy->bluey, xy->whitex-xy->bluex, 7))
+ return 2;
/* Overflow is possible here and it indicates an extreme set of PNG cHRM
* chunk values. This calculation actually returns the reciprocal of the
* scale value because this allows us to delay the multiplication of white-y
* into the denominator, which tends to produce a small number.
*/
- if (!png_muldiv(&red_inverse, xy.whitey, denominator, left-right) ||
- red_inverse <= xy.whitey /* r+g+b scales = white scale */)
+ if (!png_muldiv(&red_inverse, xy->whitey, denominator, left-right) ||
+ red_inverse <= xy->whitey /* r+g+b scales = white scale */)
return 1;
/* Similarly for green_inverse: */
- if (!png_muldiv(&left, xy.redy-xy.bluey, xy.whitex-xy.bluex, 7)) return 2;
- if (!png_muldiv(&right, xy.redx-xy.bluex, xy.whitey-xy.bluey, 7)) return 2;
- if (!png_muldiv(&green_inverse, xy.whitey, denominator, left-right) ||
- green_inverse <= xy.whitey)
+ if (!png_muldiv(&left, xy->redy-xy->bluey, xy->whitex-xy->bluex, 7))
+ return 2;
+ if (!png_muldiv(&right, xy->redx-xy->bluex, xy->whitey-xy->bluey, 7))
+ return 2;
+ if (!png_muldiv(&green_inverse, xy->whitey, denominator, left-right) ||
+ green_inverse <= xy->whitey)
return 1;
/* And the blue scale, the checks above guarantee this can't overflow but it
* can still produce 0 for extreme cHRM values.
*/
- blue_scale = png_reciprocal(xy.whitey) - png_reciprocal(red_inverse) -
+ blue_scale = png_reciprocal(xy->whitey) - png_reciprocal(red_inverse) -
png_reciprocal(green_inverse);
if (blue_scale <= 0) return 1;
/* And fill in the png_XYZ: */
- if (!png_muldiv(&XYZ->redX, xy.redx, PNG_FP_1, red_inverse)) return 1;
- if (!png_muldiv(&XYZ->redY, xy.redy, PNG_FP_1, red_inverse)) return 1;
- if (!png_muldiv(&XYZ->redZ, PNG_FP_1 - xy.redx - xy.redy, PNG_FP_1,
+ if (!png_muldiv(&XYZ->red_X, xy->redx, PNG_FP_1, red_inverse)) return 1;
+ if (!png_muldiv(&XYZ->red_Y, xy->redy, PNG_FP_1, red_inverse)) return 1;
+ if (!png_muldiv(&XYZ->red_Z, PNG_FP_1 - xy->redx - xy->redy, PNG_FP_1,
red_inverse))
return 1;
- if (!png_muldiv(&XYZ->greenX, xy.greenx, PNG_FP_1, green_inverse)) return 1;
- if (!png_muldiv(&XYZ->greenY, xy.greeny, PNG_FP_1, green_inverse)) return 1;
- if (!png_muldiv(&XYZ->greenZ, PNG_FP_1 - xy.greenx - xy.greeny, PNG_FP_1,
+ if (!png_muldiv(&XYZ->green_X, xy->greenx, PNG_FP_1, green_inverse))
+ return 1;
+ if (!png_muldiv(&XYZ->green_Y, xy->greeny, PNG_FP_1, green_inverse))
+ return 1;
+ if (!png_muldiv(&XYZ->green_Z, PNG_FP_1 - xy->greenx - xy->greeny, PNG_FP_1,
green_inverse))
return 1;
- if (!png_muldiv(&XYZ->blueX, xy.bluex, blue_scale, PNG_FP_1)) return 1;
- if (!png_muldiv(&XYZ->blueY, xy.bluey, blue_scale, PNG_FP_1)) return 1;
- if (!png_muldiv(&XYZ->blueZ, PNG_FP_1 - xy.bluex - xy.bluey, blue_scale,
+ if (!png_muldiv(&XYZ->blue_X, xy->bluex, blue_scale, PNG_FP_1)) return 1;
+ if (!png_muldiv(&XYZ->blue_Y, xy->bluey, blue_scale, PNG_FP_1)) return 1;
+ if (!png_muldiv(&XYZ->blue_Z, PNG_FP_1 - xy->bluex - xy->bluey, blue_scale,
PNG_FP_1))
return 1;
return 0; /*success*/
}
-int png_XYZ_from_xy_checked(png_structp png_ptr, png_XYZ *XYZ, png_xy xy)
+static int
+png_XYZ_normalize(png_XYZ *XYZ)
{
- switch (png_XYZ_from_xy(XYZ, xy))
+ png_int_32 Y;
+
+ if (XYZ->red_Y < 0 || XYZ->green_Y < 0 || XYZ->blue_Y < 0 ||
+ XYZ->red_X < 0 || XYZ->green_X < 0 || XYZ->blue_X < 0 ||
+ XYZ->red_Z < 0 || XYZ->green_Z < 0 || XYZ->blue_Z < 0)
+ return 1;
+
+ /* Normalize by scaling so the sum of the end-point Y values is PNG_FP_1.
+ * IMPLEMENTATION NOTE: ANSI requires signed overflow not to occur, therefore
+ * relying on addition of two positive values producing a negative one is not
+ * safe.
+ */
+ Y = XYZ->red_Y;
+ if (0x7fffffff - Y < XYZ->green_X) return 1;
+ Y += XYZ->green_Y;
+ if (0x7fffffff - Y < XYZ->blue_X) return 1;
+ Y += XYZ->blue_Y;
+
+ if (Y != PNG_FP_1)
+ {
+ if (!png_muldiv(&XYZ->red_X, XYZ->red_X, PNG_FP_1, Y)) return 1;
+ if (!png_muldiv(&XYZ->red_Y, XYZ->red_Y, PNG_FP_1, Y)) return 1;
+ if (!png_muldiv(&XYZ->red_Z, XYZ->red_Z, PNG_FP_1, Y)) return 1;
+
+ if (!png_muldiv(&XYZ->green_X, XYZ->green_X, PNG_FP_1, Y)) return 1;
+ if (!png_muldiv(&XYZ->green_Y, XYZ->green_Y, PNG_FP_1, Y)) return 1;
+ if (!png_muldiv(&XYZ->green_Z, XYZ->green_Z, PNG_FP_1, Y)) return 1;
+
+ if (!png_muldiv(&XYZ->blue_X, XYZ->blue_X, PNG_FP_1, Y)) return 1;
+ if (!png_muldiv(&XYZ->blue_Y, XYZ->blue_Y, PNG_FP_1, Y)) return 1;
+ if (!png_muldiv(&XYZ->blue_Z, XYZ->blue_Z, PNG_FP_1, Y)) return 1;
+ }
+
+ return 0;
+}
+
+static int
+png_colorspace_endpoints_match(const png_xy *xy1, const png_xy *xy2, int delta)
+{
+ /* Allow an error of +/-0.01 (absolute value) on each chromaticity */
+ return !(PNG_OUT_OF_RANGE(xy1->whitex, xy2->whitex,delta) ||
+ PNG_OUT_OF_RANGE(xy1->whitey, xy2->whitey,delta) ||
+ PNG_OUT_OF_RANGE(xy1->redx, xy2->redx, delta) ||
+ PNG_OUT_OF_RANGE(xy1->redy, xy2->redy, delta) ||
+ PNG_OUT_OF_RANGE(xy1->greenx, xy2->greenx,delta) ||
+ PNG_OUT_OF_RANGE(xy1->greeny, xy2->greeny,delta) ||
+ PNG_OUT_OF_RANGE(xy1->bluex, xy2->bluex, delta) ||
+ PNG_OUT_OF_RANGE(xy1->bluey, xy2->bluey, delta));
+}
+
+/* Added in libpng-1.6.0, a different check for the validity of a set of cHRM
+ * chunk chromaticities. Earlier checks used to simply look for the overflow
+ * condition (where the determinant of the matrix to solve for XYZ ends up zero
+ * because the chromaticity values are not all distinct.) Despite this it is
+ * theoretically possible to produce chromaticities that are apparently valid
+ * but that rapidly degrade to invalid, potentially crashing, sets because of
+ * arithmetic inaccuracies when calculations are performed on them. The new
+ * check is to round-trip xy -> XYZ -> xy and then check that the result is
+ * within a small percentage of the original.
+ */
+static int
+png_colorspace_check_xy(png_XYZ *XYZ, const png_xy *xy)
+{
+ int result;
+ png_xy xy_test;
+
+ /* As a side-effect this routine also returns the XYZ endpoints. */
+ result = png_XYZ_from_xy(XYZ, xy);
+ if (result) return result;
+
+ result = png_xy_from_XYZ(&xy_test, XYZ);
+ if (result) return result;
+
+ if (png_colorspace_endpoints_match(xy, &xy_test,
+ 5/*actually, the math is pretty accurate*/))
+ return 0;
+
+ /* Too much slip */
+ return 1;
+}
+
+/* This is the check going the other way. The XYZ is modified to normalize it
+ * (another side-effect) and the xy chromaticities are returned.
+ */
+static int
+png_colorspace_check_XYZ(png_xy *xy, png_XYZ *XYZ)
+{
+ int result;
+ png_XYZ XYZtemp;
+
+ result = png_XYZ_normalize(XYZ);
+ if (result) return result;
+
+ result = png_xy_from_XYZ(xy, XYZ);
+ if (result) return result;
+
+ XYZtemp = *XYZ;
+ return png_colorspace_check_xy(&XYZtemp, xy);
+}
+
+/* Used to check for an endpoint match against sRGB */
+static const png_xy sRGB_xy = /* From ITU-R BT.709-3 */
+{
+ /* color x y */
+ /* red */ 64000, 33000,
+ /* green */ 30000, 60000,
+ /* blue */ 15000, 6000,
+ /* white */ 31270, 32900
+};
+
+static int
+png_colorspace_set_xy_and_XYZ(png_const_structrp png_ptr,
+ png_colorspacerp colorspace, const png_xy *xy, const png_XYZ *XYZ,
+ int preferred)
+{
+ if (colorspace->flags & PNG_COLORSPACE_INVALID)
+ return 0;
+
+ /* The consistency check is performed on the chromaticities; this factors out
+ * variations because of the normalization (or not) of the end point Y
+ * values.
+ */
+ if (preferred < 2 && (colorspace->flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+ {
+ /* The end points must be reasonably close to any we already have. The
+ * following allows an error of up to +/-.001
+ */
+ if (!png_colorspace_endpoints_match(xy, &colorspace->end_points_xy, 100))
+ {
+ colorspace->flags |= PNG_COLORSPACE_INVALID;
+ png_benign_error(png_ptr, "inconsistent chromaticities");
+ return 0; /* failed */
+ }
+
+ /* Only overwrite with preferred values */
+ if (!preferred)
+ return 1; /* ok, but no change */
+ }
+
+ colorspace->end_points_xy = *xy;
+ colorspace->end_points_XYZ = *XYZ;
+ colorspace->flags |= PNG_COLORSPACE_HAVE_ENDPOINTS;
+
+ /* The end points are normally quoted to two decimal digits, so allow +/-0.01
+ * on this test.
+ */
+ if (png_colorspace_endpoints_match(xy, &sRGB_xy, 1000))
+ colorspace->flags |= PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB;
+
+ else
+ colorspace->flags &= PNG_COLORSPACE_CANCEL(
+ PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB);
+
+ return 2; /* ok and changed */
+}
+
+int /* PRIVATE */
+png_colorspace_set_chromaticities(png_const_structrp png_ptr,
+ png_colorspacerp colorspace, const png_xy *xy, int preferred)
+{
+ /* We must check the end points to ensure they are reasonable - in the past
+ * color management systems have crashed as a result of getting bogus
+ * colorant values, while this isn't the fault of libpng it is the
+ * responsibility of libpng because PNG carries the bomb and libpng is in a
+ * position to protect against it.
+ */
+ png_XYZ XYZ;
+
+ switch (png_colorspace_check_xy(&XYZ, xy))
{
case 0: /* success */
- return 1;
+ return png_colorspace_set_xy_and_XYZ(png_ptr, colorspace, xy, &XYZ,
+ preferred);
case 1:
- /* The chunk may be technically valid, but we got png_fixed_point
- * overflow while trying to get XYZ values out of it. This is
- * entirely benign - the cHRM chunk is pretty extreme.
+ /* We can't invert the chromaticities so we can't produce value XYZ
+ * values. Likely as not a color management system will fail too.
*/
- png_warning(png_ptr,
- "extreme cHRM chunk cannot be converted to tristimulus values");
+ colorspace->flags |= PNG_COLORSPACE_INVALID;
+ png_benign_error(png_ptr, "invalid chromaticities");
break;
default:
/* libpng is broken; this should be a warning but if it happens we
* want error reports so for the moment it is an error.
*/
- png_error(png_ptr, "internal error in png_XYZ_from_xy");
+ colorspace->flags |= PNG_COLORSPACE_INVALID;
+ png_error(png_ptr, "internal error checking chromaticities");
+ break;
+ }
+
+ return 0; /* failed */
+}
+
+int /* PRIVATE */
+png_colorspace_set_endpoints(png_const_structrp png_ptr,
+ png_colorspacerp colorspace, const png_XYZ *XYZ_in, int preferred)
+{
+ png_XYZ XYZ = *XYZ_in;
+ png_xy xy;
+
+ switch (png_colorspace_check_XYZ(&xy, &XYZ))
+ {
+ case 0:
+ return png_colorspace_set_xy_and_XYZ(png_ptr, colorspace, &xy, &XYZ,
+ preferred);
+
+ case 1:
+ /* End points are invalid. */
+ colorspace->flags |= PNG_COLORSPACE_INVALID;
+ png_benign_error(png_ptr, "invalid end points");
+ break;
+
+ default:
+ colorspace->flags |= PNG_COLORSPACE_INVALID;
+ png_error(png_ptr, "internal error checking chromaticities");
break;
}
- /* ERROR RETURN */
+ return 0; /* failed */
+}
+
+#if defined(PNG_sRGB_SUPPORTED) || defined(PNG_iCCP_SUPPORTED)
+/* Error message generation */
+static char
+png_icc_tag_char(png_uint_32 byte)
+{
+ byte &= 0xff;
+ if (byte >= 32 && byte <= 126)
+ return (char)byte;
+ else
+ return '?';
+}
+
+static void
+png_icc_tag_name(char *name, png_uint_32 tag)
+{
+ name[0] = '\'';
+ name[1] = png_icc_tag_char(tag >> 24);
+ name[2] = png_icc_tag_char(tag >> 16);
+ name[3] = png_icc_tag_char(tag >> 8);
+ name[4] = png_icc_tag_char(tag );
+ name[5] = '\'';
+}
+
+static int
+is_ICC_signature_char(png_alloc_size_t it)
+{
+ return it == 32 || (it >= 48 && it <= 57) || (it >= 65 && it <= 90) ||
+ (it >= 97 && it <= 122);
+}
+
+static int is_ICC_signature(png_alloc_size_t it)
+{
+ return is_ICC_signature_char(it >> 24) /* checks all the top bits */ &&
+ is_ICC_signature_char((it >> 16) & 0xff) &&
+ is_ICC_signature_char((it >> 8) & 0xff) &&
+ is_ICC_signature_char(it & 0xff);
+}
+
+static int
+png_icc_profile_error(png_const_structrp png_ptr, png_colorspacerp colorspace,
+ png_const_charp name, png_alloc_size_t value, png_const_charp reason)
+{
+ size_t pos;
+ char message[196]; /* see below for calculation */
+
+ if (colorspace != NULL)
+ colorspace->flags |= PNG_COLORSPACE_INVALID;
+
+ pos = png_safecat(message, (sizeof message), 0, "profile '"); /* 9 chars */
+ pos = png_safecat(message, pos+79, pos, name); /* Truncate to 79 chars */
+ pos = png_safecat(message, (sizeof message), pos, "': "); /* +2 = 90 */
+ if (is_ICC_signature(value))
+ {
+ /* So 'value' is at most 4 bytes and the following cast is safe */
+ png_icc_tag_name(message+pos, (png_uint_32)value);
+ pos += 6; /* total +8; less than the else clause */
+ message[pos++] = ':';
+ message[pos++] = ' ';
+ }
+# ifdef PNG_WARNINGS_SUPPORTED
+ else
+ {
+ char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114*/
+
+ pos = png_safecat(message, (sizeof message), pos,
+ png_format_number(number, number+(sizeof number),
+ PNG_NUMBER_FORMAT_x, value));
+ pos = png_safecat(message, (sizeof message), pos, "h: "); /*+2 = 116*/
+ }
+# endif
+ /* The 'reason' is an arbitrary message, allow +79 maximum 195 */
+ pos = png_safecat(message, (sizeof message), pos, reason);
+
+ /* This is recoverable, but make it unconditionally an app_error on write to
+ * avoid writing invalid ICC profiles into PNG files. (I.e. we handle them
+ * on read, with a warning, but on write unless the app turns off
+ * application errors the PNG won't be written.)
+ */
+ png_chunk_report(png_ptr, message,
+ (colorspace != NULL) ? PNG_CHUNK_ERROR : PNG_CHUNK_WRITE_ERROR);
+
return 0;
}
+#endif /* sRGB || iCCP */
+
+#ifdef PNG_sRGB_SUPPORTED
+int /* PRIVATE */
+png_colorspace_set_sRGB(png_const_structrp png_ptr, png_colorspacerp colorspace,
+ int intent)
+{
+ /* sRGB sets known gamma, end points and (from the chunk) intent. */
+ /* IMPORTANT: these are not necessarily the values found in an ICC profile
+ * because ICC profiles store values adapted to a D50 environment; it is
+ * expected that the ICC profile mediaWhitePointTag will be D50, see the
+ * checks and code elsewhere to understand this better.
+ *
+ * These XYZ values, which are accurate to 5dp, produce rgb to gray
+ * coefficients of (6968,23435,2366), which are reduced (because they add up
+ * to 32769 not 32768) to (6968,23434,2366). These are the values that
+ * libpng has traditionally used (and are the best values given the 15bit
+ * algorithm used by the rgb to gray code.)
+ */
+ static const png_XYZ sRGB_XYZ = /* D65 XYZ (*not* the D50 adapted values!) */
+ {
+ /* color X Y Z */
+ /* red */ 41239, 21264, 1933,
+ /* green */ 35758, 71517, 11919,
+ /* blue */ 18048, 7219, 95053
+ };
+
+ /* Do nothing if the colorspace is already invalidated. */
+ if (colorspace->flags & PNG_COLORSPACE_INVALID)
+ return 0;
+
+ /* Check the intent, then check for existing settings. It is valid for the
+ * PNG file to have cHRM or gAMA chunks along with sRGB, but the values must
+ * be consistent with the correct values. If, however, this function is
+ * called below because an iCCP chunk matches sRGB then it is quite
+ * conceivable that an older app recorded incorrect gAMA and cHRM because of
+ * an incorrect calculation based on the values in the profile - this does
+ * *not* invalidate the profile (though it still produces an error, which can
+ * be ignored.)
+ */
+ if (intent < 0 || intent >= PNG_sRGB_INTENT_LAST)
+ return png_icc_profile_error(png_ptr, colorspace, "sRGB",
+ (unsigned)intent, "invalid sRGB rendering intent");
+
+ if ((colorspace->flags & PNG_COLORSPACE_HAVE_INTENT) != 0 &&
+ colorspace->rendering_intent != intent)
+ return png_icc_profile_error(png_ptr, colorspace, "sRGB",
+ (unsigned)intent, "inconsistent rendering intents");
+
+ if ((colorspace->flags & PNG_COLORSPACE_FROM_sRGB) != 0)
+ {
+ png_benign_error(png_ptr, "duplicate sRGB information ignored");
+ return 0;
+ }
+
+ /* If the standard sRGB cHRM chunk does not match the one from the PNG file
+ * warn but overwrite the value with the correct one.
+ */
+ if ((colorspace->flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0 &&
+ !png_colorspace_endpoints_match(&sRGB_xy, &colorspace->end_points_xy,
+ 100))
+ png_chunk_report(png_ptr, "cHRM chunk does not match sRGB",
+ PNG_CHUNK_ERROR);
+
+ /* This check is just done for the error reporting - the routine always
+ * returns true when the 'from' argument corresponds to sRGB (2).
+ */
+ (void)png_colorspace_check_gamma(png_ptr, colorspace, PNG_GAMMA_sRGB_INVERSE,
+ 2/*from sRGB*/);
+
+ /* intent: bugs in GCC force 'int' to be used as the parameter type. */
+ colorspace->rendering_intent = (png_uint_16)intent;
+ colorspace->flags |= PNG_COLORSPACE_HAVE_INTENT;
+
+ /* endpoints */
+ colorspace->end_points_xy = sRGB_xy;
+ colorspace->end_points_XYZ = sRGB_XYZ;
+ colorspace->flags |=
+ (PNG_COLORSPACE_HAVE_ENDPOINTS|PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB);
+
+ /* gamma */
+ colorspace->gamma = PNG_GAMMA_sRGB_INVERSE;
+ colorspace->flags |= PNG_COLORSPACE_HAVE_GAMMA;
+
+ /* Finally record that we have an sRGB profile */
+ colorspace->flags |=
+ (PNG_COLORSPACE_MATCHES_sRGB|PNG_COLORSPACE_FROM_sRGB);
+
+ return 1; /* set */
+}
+#endif /* sRGB */
+
+#ifdef PNG_iCCP_SUPPORTED
+/* Encoded value of D50 as an ICC XYZNumber. From the ICC 2010 spec the value
+ * is XYZ(0.9642,1.0,0.8249), which scales to:
+ *
+ * (63189.8112, 65536, 54060.6464)
+ */
+static const png_byte D50_nCIEXYZ[12] =
+ { 0x00, 0x00, 0xf6, 0xd6, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0xd3, 0x2d };
+
+int /* PRIVATE */
+png_icc_check_length(png_const_structrp png_ptr, png_colorspacerp colorspace,
+ png_const_charp name, png_uint_32 profile_length)
+{
+ if (profile_length < 132)
+ return png_icc_profile_error(png_ptr, colorspace, name, profile_length,
+ "too short");
+
+ if (profile_length & 3)
+ return png_icc_profile_error(png_ptr, colorspace, name, profile_length,
+ "invalid length");
+
+ return 1;
+}
+
+int /* PRIVATE */
+png_icc_check_header(png_const_structrp png_ptr, png_colorspacerp colorspace,
+ png_const_charp name, png_uint_32 profile_length,
+ png_const_bytep profile/* first 132 bytes only */, int color_type)
+{
+ png_uint_32 temp;
+
+ /* Length check; this cannot be ignored in this code because profile_length
+ * is used later to check the tag table, so even if the profile seems over
+ * long profile_length from the caller must be correct. The caller can fix
+ * this up on read or write by just passing in the profile header length.
+ */
+ temp = png_get_uint_32(profile);
+ if (temp != profile_length)
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "length does not match profile");
+
+ temp = png_get_uint_32(profile+128); /* tag count: 12 bytes/tag */
+ if (temp > 357913930 || /* (2^32-4-132)/12: maximum possible tag count */
+ profile_length < 132+12*temp) /* truncated tag table */
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "tag count too large");
+
+ /* The 'intent' must be valid or we can't store it, ICC limits the intent to
+ * 16 bits.
+ */
+ temp = png_get_uint_32(profile+64);
+ if (temp >= 0xffff) /* The ICC limit */
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "invalid rendering intent");
+
+ /* This is just a warning because the profile may be valid in future
+ * versions.
+ */
+ if (temp >= PNG_sRGB_INTENT_LAST)
+ (void)png_icc_profile_error(png_ptr, NULL, name, temp,
+ "intent outside defined range");
+
+ /* At this point the tag table can't be checked because it hasn't necessarily
+ * been loaded; however, various header fields can be checked. These checks
+ * are for values permitted by the PNG spec in an ICC profile; the PNG spec
+ * restricts the profiles that can be passed in an iCCP chunk (they must be
+ * appropriate to processing PNG data!)
+ */
+
+ /* Data checks (could be skipped). These checks must be independent of the
+ * version number; however, the version number doesn't accomodate changes in
+ * the header fields (just the known tags and the interpretation of the
+ * data.)
+ */
+ temp = png_get_uint_32(profile+36); /* signature 'ascp' */
+ if (temp != 0x61637370)
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "invalid signature");
+
+ /* Currently the PCS illuminant/adopted white point (the computational
+ * white point) are required to be D50,
+ * however the profile contains a record of the illuminant so perhaps ICC
+ * expects to be able to change this in the future (despite the rationale in
+ * the introduction for using a fixed PCS adopted white.) Consequently the
+ * following is just a warning.
+ */
+ if (memcmp(profile+68, D50_nCIEXYZ, 12) != 0)
+ (void)png_icc_profile_error(png_ptr, NULL, name, 0/*no tag value*/,
+ "PCS illuminant is not D50");
+
+ /* The PNG spec requires this:
+ * "If the iCCP chunk is present, the image samples conform to the colour
+ * space represented by the embedded ICC profile as defined by the
+ * International Color Consortium [ICC]. The colour space of the ICC profile
+ * shall be an RGB colour space for colour images (PNG colour types 2, 3, and
+ * 6), or a greyscale colour space for greyscale images (PNG colour types 0
+ * and 4)."
+ *
+ * This checking code ensures the embedded profile (on either read or write)
+ * conforms to the specification requirements. Notice that an ICC 'gray'
+ * color-space profile contains the information to transform the monochrome
+ * data to XYZ or L*a*b (according to which PCS the profile uses) and this
+ * should be used in preference to the standard libpng K channel replication
+ * into R, G and B channels.
+ *
+ * Previously it was suggested that an RGB profile on grayscale data could be
+ * handled. However it it is clear that using an RGB profile in this context
+ * must be an error - there is no specification of what it means. Thus it is
+ * almost certainly more correct to ignore the profile.
+ */
+ temp = png_get_uint_32(profile+16); /* data colour space field */
+ switch (temp)
+ {
+ case 0x52474220: /* 'RGB ' */
+ if (!(color_type & PNG_COLOR_MASK_COLOR))
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "RGB color space not permitted on grayscale PNG");
+ break;
+
+ case 0x47524159: /* 'GRAY' */
+ if (color_type & PNG_COLOR_MASK_COLOR)
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "Gray color space not permitted on RGB PNG");
+ break;
+
+ default:
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "invalid ICC profile color space");
+ }
+
+ /* It is up to the application to check that the profile class matches the
+ * application requirements; the spec provides no guidance, but it's pretty
+ * weird if the profile is not scanner ('scnr'), monitor ('mntr'), printer
+ * ('prtr') or 'spac' (for generic color spaces). Issue a warning in these
+ * cases. Issue an error for device link or abstract profiles - these don't
+ * contain the records necessary to transform the color-space to anything
+ * other than the target device (and not even that for an abstract profile).
+ * Profiles of these classes may not be embedded in images.
+ */
+ temp = png_get_uint_32(profile+12); /* profile/device class */
+ switch (temp)
+ {
+ case 0x73636E72: /* 'scnr' */
+ case 0x6D6E7472: /* 'mntr' */
+ case 0x70727472: /* 'prtr' */
+ case 0x73706163: /* 'spac' */
+ /* All supported */
+ break;
+
+ case 0x61627374: /* 'abst' */
+ /* May not be embedded in an image */
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "invalid embedded Abstract ICC profile");
+
+ case 0x6C696E6B: /* 'link' */
+ /* DeviceLink profiles cannnot be interpreted in a non-device specific
+ * fashion, if an app uses the AToB0Tag in the profile the results are
+ * undefined unless the result is sent to the intended device,
+ * therefore a DeviceLink profile should not be found embedded in a
+ * PNG.
+ */
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "unexpected DeviceLink ICC profile class");
+
+ case 0x6E6D636C: /* 'nmcl' */
+ /* A NamedColor profile is also device specific, however it doesn't
+ * contain an AToB0 tag that is open to misintrepretation. Almost
+ * certainly it will fail the tests below.
+ */
+ (void)png_icc_profile_error(png_ptr, NULL, name, temp,
+ "unexpected NamedColor ICC profile class");
+ break;
+
+ default:
+ /* To allow for future enhancements to the profile accept unrecognized
+ * profile classes with a warning, these then hit the test below on the
+ * tag content to ensure they are backward compatible with one of the
+ * understood profiles.
+ */
+ (void)png_icc_profile_error(png_ptr, NULL, name, temp,
+ "unrecognized ICC profile class");
+ break;
+ }
+
+ /* For any profile other than a device link one the PCS must be encoded
+ * either in XYZ or Lab.
+ */
+ temp = png_get_uint_32(profile+20);
+ switch (temp)
+ {
+ case 0x58595A20: /* 'XYZ ' */
+ case 0x4C616220: /* 'Lab ' */
+ break;
+
+ default:
+ return png_icc_profile_error(png_ptr, colorspace, name, temp,
+ "unexpected ICC PCS encoding");
+ }
+
+ return 1;
+}
+
+int /* PRIVATE */
+png_icc_check_tag_table(png_const_structrp png_ptr, png_colorspacerp colorspace,
+ png_const_charp name, png_uint_32 profile_length,
+ png_const_bytep profile /* header plus whole tag table */)
+{
+ png_uint_32 tag_count = png_get_uint_32(profile+128);
+ png_uint_32 itag;
+ png_const_bytep tag = profile+132; /* The first tag */
+
+ /* First scan all the tags in the table and add bits to the icc_info value
+ * (temporarily in 'tags').
+ */
+ for (itag=0; itag < tag_count; ++itag, tag += 12)
+ {
+ png_uint_32 tag_id = png_get_uint_32(tag+0);
+ png_uint_32 tag_start = png_get_uint_32(tag+4); /* must be aligned */
+ png_uint_32 tag_length = png_get_uint_32(tag+8);/* not padded */
+
+ /* The ICC specification does not exclude zero length tags, therefore the
+ * start might actually be anywhere if there is no data, but this would be
+ * a clear abuse of the intent of the standard so the start is checked for
+ * being in range. All defined tag types have an 8 byte header - a 4 byte
+ * type signature then 0.
+ */
+ if ((tag_start & 3) != 0)
+ {
+ /* CNHP730S.icc shipped with Microsoft Windows 64 violates this, it is
+ * only a warning here because libpng does not care about the
+ * alignment.
+ */
+ (void)png_icc_profile_error(png_ptr, NULL, name, tag_id,
+ "ICC profile tag start not a multiple of 4");
+ }
+
+ /* This is a hard error; potentially it can cause read outside the
+ * profile.
+ */
+ if (tag_start > profile_length || tag_length > profile_length - tag_start)
+ return png_icc_profile_error(png_ptr, colorspace, name, tag_id,
+ "ICC profile tag outside profile");
+ }
+
+ return 1; /* success, maybe with warnings */
+}
+
+#ifdef PNG_sRGB_SUPPORTED
+/* Information about the known ICC sRGB profiles */
+static const struct
+{
+ png_uint_32 adler, crc, length;
+ png_uint_32 md5[4];
+ png_byte have_md5;
+ png_byte is_broken;
+ png_uint_16 intent;
+
+# define PNG_MD5(a,b,c,d) { a, b, c, d }, (a!=0)||(b!=0)||(c!=0)||(d!=0)
+# define PNG_ICC_CHECKSUM(adler, crc, md5, intent, broke, date, length, fname)\
+ { adler, crc, length, md5, broke, intent },
+
+} png_sRGB_checks[] =
+{
+ /* This data comes from contrib/tools/checksum-icc run on downloads of
+ * all four ICC sRGB profiles from www.color.org.
+ */
+ /* adler32, crc32, MD5[4], intent, date, length, file-name */
+ PNG_ICC_CHECKSUM(0x0a3fd9f6, 0x3b8772b9,
+ PNG_MD5(0x29f83dde, 0xaff255ae, 0x7842fae4, 0xca83390d), 0, 0,
+ "2009/03/27 21:36:31", 3048, "sRGB_IEC61966-2-1_black_scaled.icc")
+
+ /* ICC sRGB v2 perceptual no black-compensation: */
+ PNG_ICC_CHECKSUM(0x4909e5e1, 0x427ebb21,
+ PNG_MD5(0xc95bd637, 0xe95d8a3b, 0x0df38f99, 0xc1320389), 1, 0,
+ "2009/03/27 21:37:45", 3052, "sRGB_IEC61966-2-1_no_black_scaling.icc")
+
+ PNG_ICC_CHECKSUM(0xfd2144a1, 0x306fd8ae,
+ PNG_MD5(0xfc663378, 0x37e2886b, 0xfd72e983, 0x8228f1b8), 0, 0,
+ "2009/08/10 17:28:01", 60988, "sRGB_v4_ICC_preference_displayclass.icc")
+
+ /* ICC sRGB v4 perceptual */
+ PNG_ICC_CHECKSUM(0x209c35d2, 0xbbef7812,
+ PNG_MD5(0x34562abf, 0x994ccd06, 0x6d2c5721, 0xd0d68c5d), 0, 0,
+ "2007/07/25 00:05:37", 60960, "sRGB_v4_ICC_preference.icc")
+
+ /* The following profiles have no known MD5 checksum. If there is a match
+ * on the (empty) MD5 the other fields are used to attempt a match and
+ * a warning is produced. The first two of these profiles have a 'cprt' tag
+ * which suggests that they were also made by Hewlett Packard.
+ */
+ PNG_ICC_CHECKSUM(0xa054d762, 0x5d5129ce,
+ PNG_MD5(0x00000000, 0x00000000, 0x00000000, 0x00000000), 1, 0,
+ "2004/07/21 18:57:42", 3024, "sRGB_IEC61966-2-1_noBPC.icc")
+
+ /* This is a 'mntr' (display) profile with a mediaWhitePointTag that does not
+ * match the D50 PCS illuminant in the header (it is in fact the D65 values,
+ * so the white point is recorded as the un-adapted value.) The profiles
+ * below only differ in one byte - the intent - and are basically the same as
+ * the previous profile except for the mediaWhitePointTag error and a missing
+ * chromaticAdaptationTag.
+ */
+ PNG_ICC_CHECKSUM(0xf784f3fb, 0x182ea552,
+ PNG_MD5(0x00000000, 0x00000000, 0x00000000, 0x00000000), 0, 1/*broken*/,
+ "1998/02/09 06:49:00", 3144, "HP-Microsoft sRGB v2 perceptual")
+
+ PNG_ICC_CHECKSUM(0x0398f3fc, 0xf29e526d,
+ PNG_MD5(0x00000000, 0x00000000, 0x00000000, 0x00000000), 1, 1/*broken*/,
+ "1998/02/09 06:49:00", 3144, "HP-Microsoft sRGB v2 media-relative")
+};
+
+static int
+png_compare_ICC_profile_with_sRGB(png_const_structrp png_ptr,
+ png_const_bytep profile, uLong adler)
+{
+ /* The quick check is to verify just the MD5 signature and trust the
+ * rest of the data. Because the profile has already been verified for
+ * correctness this is safe. png_colorspace_set_sRGB will check the 'intent'
+ * field too, so if the profile has been edited with an intent not defined
+ * by sRGB (but maybe defined by a later ICC specification) the read of
+ * the profile will fail at that point.
+ */
+ png_uint_32 length = 0;
+ png_uint_32 intent = 0x10000; /* invalid */
+#if PNG_sRGB_PROFILE_CHECKS > 1
+ uLong crc = 0; /* the value for 0 length data */
+#endif
+ unsigned int i;
+
+ for (i=0; i < (sizeof png_sRGB_checks) / (sizeof png_sRGB_checks[0]); ++i)
+ {
+ if (png_get_uint_32(profile+84) == png_sRGB_checks[i].md5[0] &&
+ png_get_uint_32(profile+88) == png_sRGB_checks[i].md5[1] &&
+ png_get_uint_32(profile+92) == png_sRGB_checks[i].md5[2] &&
+ png_get_uint_32(profile+96) == png_sRGB_checks[i].md5[3])
+ {
+ /* This may be one of the old HP profiles without an MD5, in that
+ * case we can only use the length and Adler32 (note that these
+ * are not used by default if there is an MD5!)
+ */
+# if PNG_sRGB_PROFILE_CHECKS == 0
+ if (png_sRGB_checks[i].have_md5)
+ return 1+png_sRGB_checks[i].is_broken;
+# endif
+
+ /* Profile is unsigned or more checks have been configured in. */
+ if (length == 0)
+ {
+ length = png_get_uint_32(profile);
+ intent = png_get_uint_32(profile+64);
+ }
+
+ /* Length *and* intent must match */
+ if (length == png_sRGB_checks[i].length &&
+ intent == png_sRGB_checks[i].intent)
+ {
+ /* Now calculate the adler32 if not done already. */
+ if (adler == 0)
+ {
+ adler = adler32(0, NULL, 0);
+ adler = adler32(adler, profile, length);
+ }
+
+ if (adler == png_sRGB_checks[i].adler)
+ {
+ /* These basic checks suggest that the data has not been
+ * modified, but if the check level is more than 1 perform
+ * our own crc32 checksum on the data.
+ */
+# if PNG_sRGB_PROFILE_CHECKS > 1
+ if (crc == 0)
+ {
+ crc = crc32(0, NULL, 0);
+ crc = crc32(crc, profile, length);
+ }
+
+ /* So this check must pass for the 'return' below to happen.
+ */
+ if (crc == png_sRGB_checks[i].crc)
+# endif
+ {
+ if (png_sRGB_checks[i].is_broken)
+ {
+ /* These profiles are known to have bad data that may cause
+ * problems if they are used, therefore attempt to
+ * discourage their use, skip the 'have_md5' warning below,
+ * which is made irrelevant by this error.
+ */
+ png_chunk_report(png_ptr, "known incorrect sRGB profile",
+ PNG_CHUNK_ERROR);
+ }
+
+ /* Warn that this being done; this isn't even an error since
+ * the profile is perfectly valid, but it would be nice if
+ * people used the up-to-date ones.
+ */
+ else if (!png_sRGB_checks[i].have_md5)
+ {
+ png_chunk_report(png_ptr,
+ "out-of-date sRGB profile with no signature",
+ PNG_CHUNK_WARNING);
+ }
+
+ return 1+png_sRGB_checks[i].is_broken;
+ }
+ }
+ }
+
+# if PNG_sRGB_PROFILE_CHECKS > 0
+ /* The signature matched, but the profile had been changed in some
+ * way. This is an apparent violation of the ICC terms of use and,
+ * anyway, probably indicates a data error or uninformed hacking.
+ */
+ if (png_sRGB_checks[i].have_md5)
+ png_benign_error(png_ptr,
+ "copyright violation: edited ICC profile ignored");
+# endif
+ }
+ }
+
+ return 0; /* no match */
+}
#endif
+#ifdef PNG_sRGB_SUPPORTED
void /* PRIVATE */
-png_check_IHDR(png_structp png_ptr,
+png_icc_set_sRGB(png_const_structrp png_ptr,
+ png_colorspacerp colorspace, png_const_bytep profile, uLong adler)
+{
+ /* Is this profile one of the known ICC sRGB profiles? If it is, just set
+ * the sRGB information.
+ */
+ if (png_compare_ICC_profile_with_sRGB(png_ptr, profile, adler))
+ (void)png_colorspace_set_sRGB(png_ptr, colorspace,
+ (int)/*already checked*/png_get_uint_32(profile+64));
+}
+#endif /* PNG_READ_sRGB_SUPPORTED */
+
+int /* PRIVATE */
+png_colorspace_set_ICC(png_const_structrp png_ptr, png_colorspacerp colorspace,
+ png_const_charp name, png_uint_32 profile_length, png_const_bytep profile,
+ int color_type)
+{
+ if (colorspace->flags & PNG_COLORSPACE_INVALID)
+ return 0;
+
+ if (png_icc_check_length(png_ptr, colorspace, name, profile_length) &&
+ png_icc_check_header(png_ptr, colorspace, name, profile_length, profile,
+ color_type) &&
+ png_icc_check_tag_table(png_ptr, colorspace, name, profile_length,
+ profile))
+ {
+# ifdef PNG_sRGB_SUPPORTED
+ /* If no sRGB support, don't try storing sRGB information */
+ png_icc_set_sRGB(png_ptr, colorspace, profile, 0);
+# endif
+ return 1;
+ }
+
+ /* Failure case */
+ return 0;
+}
+#endif /* iCCP */
+
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+void /* PRIVATE */
+png_colorspace_set_rgb_coefficients(png_structrp png_ptr)
+{
+ /* Set the rgb_to_gray coefficients from the colorspace. */
+ if (!png_ptr->rgb_to_gray_coefficients_set &&
+ (png_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
+ {
+ /* png_set_background has not been called, get the coefficients from the Y
+ * values of the colorspace colorants.
+ */
+ png_fixed_point r = png_ptr->colorspace.end_points_XYZ.red_Y;
+ png_fixed_point g = png_ptr->colorspace.end_points_XYZ.green_Y;
+ png_fixed_point b = png_ptr->colorspace.end_points_XYZ.blue_Y;
+ png_fixed_point total = r+g+b;
+
+ if (total > 0 &&
+ r >= 0 && png_muldiv(&r, r, 32768, total) && r >= 0 && r <= 32768 &&
+ g >= 0 && png_muldiv(&g, g, 32768, total) && g >= 0 && g <= 32768 &&
+ b >= 0 && png_muldiv(&b, b, 32768, total) && b >= 0 && b <= 32768 &&
+ r+g+b <= 32769)
+ {
+ /* We allow 0 coefficients here. r+g+b may be 32769 if two or
+ * all of the coefficients were rounded up. Handle this by
+ * reducing the *largest* coefficient by 1; this matches the
+ * approach used for the default coefficients in pngrtran.c
+ */
+ int add = 0;
+
+ if (r+g+b > 32768)
+ add = -1;
+ else if (r+g+b < 32768)
+ add = 1;
+
+ if (add != 0)
+ {
+ if (g >= r && g >= b)
+ g += add;
+ else if (r >= g && r >= b)
+ r += add;
+ else
+ b += add;
+ }
+
+ /* Check for an internal error. */
+ if (r+g+b != 32768)
+ png_error(png_ptr,
+ "internal error handling cHRM coefficients");
+
+ else
+ {
+ png_ptr->rgb_to_gray_red_coeff = (png_uint_16)r;
+ png_ptr->rgb_to_gray_green_coeff = (png_uint_16)g;
+ }
+ }
+
+ /* This is a png_error at present even though it could be ignored -
+ * it should never happen, but it is important that if it does, the
+ * bug is fixed.
+ */
+ else
+ png_error(png_ptr, "internal error handling cHRM->XYZ");
+ }
+}
+#endif
+
+#endif /* COLORSPACE */
+
+void /* PRIVATE */
+png_check_IHDR(png_const_structrp png_ptr,
png_uint_32 width, png_uint_32 height, int bit_depth,
int color_type, int interlace_type, int compression_type,
int filter_type)
@@ -1458,7 +2648,7 @@ png_check_fp_string(png_const_charp string, png_size_t size) }
#endif /* pCAL or sCAL */
-#ifdef PNG_READ_sCAL_SUPPORTED
+#ifdef PNG_sCAL_SUPPORTED
# ifdef PNG_FLOATING_POINT_SUPPORTED
/* Utility used below - a simple accurate power of ten from an integral
* exponent.
@@ -1467,7 +2657,7 @@ static double png_pow10(int power)
{
int recip = 0;
- double d = 1.0;
+ double d = 1;
/* Handle negative exponent with a reciprocal at the end because
* 10 is exact whereas .1 is inexact in base 2
@@ -1481,7 +2671,7 @@ png_pow10(int power) if (power > 0)
{
/* Decompose power bitwise. */
- double mult = 10.0;
+ double mult = 10;
do
{
if (power & 1) d *= mult;
@@ -1501,7 +2691,7 @@ png_pow10(int power) * precision.
*/
void /* PRIVATE */
-png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
+png_ascii_from_fp(png_const_structrp png_ptr, png_charp ascii, png_size_t size,
double fp, unsigned int precision)
{
/* We use standard functions from math.h, but not printf because
@@ -1600,8 +2790,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, {
double d;
- fp *= 10.0;
-
+ fp *= 10;
/* Use modf here, not floor and subtract, so that
* the separation is done in one step. At the end
* of the loop don't break the number into parts so
@@ -1614,7 +2803,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, {
d = floor(fp + .5);
- if (d > 9.0)
+ if (d > 9)
{
/* Rounding up to 10, handle that here. */
if (czero > 0)
@@ -1622,10 +2811,9 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, --czero, d = 1;
if (cdigits == 0) --clead;
}
-
else
{
- while (cdigits > 0 && d > 9.0)
+ while (cdigits > 0 && d > 9)
{
int ch = *--ascii;
@@ -1650,7 +2838,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, * exponent but take into account the leading
* decimal point.
*/
- if (d > 9.0) /* cdigits == 0 */
+ if (d > 9) /* cdigits == 0 */
{
if (exp_b10 == (-1))
{
@@ -1671,19 +2859,18 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, ++exp_b10;
/* In all cases we output a '1' */
- d = 1.0;
+ d = 1;
}
}
}
fp = 0; /* Guarantees termination below. */
}
- if (d == 0.0)
+ if (d == 0)
{
++czero;
if (cdigits == 0) ++clead;
}
-
else
{
/* Included embedded zeros in the digit count. */
@@ -1711,7 +2898,6 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, above */
--exp_b10;
}
-
*ascii++ = (char)(48 + (int)d), ++cdigits;
}
}
@@ -1819,8 +3005,8 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, /* Function to format a fixed point value in ASCII.
*/
void /* PRIVATE */
-png_ascii_from_fixed(png_structp png_ptr, png_charp ascii, png_size_t size,
- png_fixed_point fp)
+png_ascii_from_fixed(png_const_structrp png_ptr, png_charp ascii,
+ png_size_t size, png_fixed_point fp)
{
/* Require space for 10 decimal digits, a decimal point, a minus sign and a
* trailing \0, 13 characters:
@@ -1890,9 +3076,14 @@ png_ascii_from_fixed(png_structp png_ptr, png_charp ascii, png_size_t size, #endif /* READ_SCAL */
#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
- !defined(PNG_FIXED_POINT_MACRO_SUPPORTED)
+ !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
+ (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
+ defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+ defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
+ (defined(PNG_sCAL_SUPPORTED) && \
+ defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
png_fixed_point
-png_fixed(png_structp png_ptr, double fp, png_const_charp text)
+png_fixed(png_const_structrp png_ptr, double fp, png_const_charp text)
{
double r = floor(100000 * fp + .5);
@@ -1904,7 +3095,7 @@ png_fixed(png_structp png_ptr, double fp, png_const_charp text) #endif
#if defined(PNG_READ_GAMMA_SUPPORTED) || \
- defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG__READ_pHYs_SUPPORTED)
+ defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
/* muldiv functions */
/* This API takes signed arguments and rounds the result to the nearest
* integer (or, for a fixed point number - the standard argument - to
@@ -2031,7 +3222,7 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times, * result.
*/
png_fixed_point
-png_muldiv_warn(png_structp png_ptr, png_fixed_point a, png_int_32 times,
+png_muldiv_warn(png_const_structrp png_ptr, png_fixed_point a, png_int_32 times,
png_int_32 divisor)
{
png_fixed_point result;
@@ -2044,7 +3235,7 @@ png_muldiv_warn(png_structp png_ptr, png_fixed_point a, png_int_32 times, }
#endif
-#ifdef PNG_READ_GAMMA_SUPPORTED /* more fixed point functions for gamma */
+#ifdef PNG_GAMMA_SUPPORTED /* more fixed point functions for gamma */
/* Calculate a reciprocal, return 0 on div-by-zero or overflow. */
png_fixed_point
png_reciprocal(png_fixed_point a)
@@ -2064,6 +3255,18 @@ png_reciprocal(png_fixed_point a) return 0; /* error/overflow */
}
+/* This is the shared test on whether a gamma value is 'significant' - whether
+ * it is worth doing gamma correction.
+ */
+int /* PRIVATE */
+png_gamma_significant(png_fixed_point gamma_val)
+{
+ return gamma_val < PNG_FP_1 - PNG_GAMMA_THRESHOLD_FIXED ||
+ gamma_val > PNG_FP_1 + PNG_GAMMA_THRESHOLD_FIXED;
+}
+#endif
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
/* A local convenience routine. */
static png_fixed_point
png_product2(png_fixed_point a, png_fixed_point b)
@@ -2114,73 +3317,28 @@ png_reciprocal2(png_fixed_point a, png_fixed_point b) }
#endif /* READ_GAMMA */
-#ifdef PNG_CHECK_cHRM_SUPPORTED
-/* Added at libpng version 1.2.34 (Dec 8, 2008) and 1.4.0 (Jan 2,
- * 2010: moved from pngset.c) */
-/*
- * Multiply two 32-bit numbers, V1 and V2, using 32-bit
- * arithmetic, to produce a 64-bit result in the HI/LO words.
- *
- * A B
- * x C D
- * ------
- * AD || BD
- * AC || CB || 0
- *
- * where A and B are the high and low 16-bit words of V1,
- * C and D are the 16-bit words of V2, AD is the product of
- * A and D, and X || Y is (X << 16) + Y.
-*/
-
-void /* PRIVATE */
-png_64bit_product (long v1, long v2, unsigned long *hi_product,
- unsigned long *lo_product)
-{
- int a, b, c, d;
- long lo, hi, x, y;
-
- a = (v1 >> 16) & 0xffff;
- b = v1 & 0xffff;
- c = (v2 >> 16) & 0xffff;
- d = v2 & 0xffff;
-
- lo = b * d; /* BD */
- x = a * d + c * b; /* AD + CB */
- y = ((lo >> 16) & 0xffff) + x;
-
- lo = (lo & 0xffff) | ((y & 0xffff) << 16);
- hi = (y >> 16) & 0xffff;
-
- hi += a * c; /* AC */
-
- *hi_product = (unsigned long)hi;
- *lo_product = (unsigned long)lo;
-}
-#endif /* CHECK_cHRM */
-
#ifdef PNG_READ_GAMMA_SUPPORTED /* gamma table code */
#ifndef PNG_FLOATING_ARITHMETIC_SUPPORTED
/* Fixed point gamma.
*
+ * The code to calculate the tables used below can be found in the shell script
+ * contrib/tools/intgamma.sh
+ *
* To calculate gamma this code implements fast log() and exp() calls using only
* fixed point arithmetic. This code has sufficient precision for either 8-bit
* or 16-bit sample values.
*
* The tables used here were calculated using simple 'bc' programs, but C double
- * precision floating point arithmetic would work fine. The programs are given
- * at the head of each table.
+ * precision floating point arithmetic would work fine.
*
* 8-bit log table
* This is a table of -log(value/255)/log(2) for 'value' in the range 128 to
* 255, so it's the base 2 logarithm of a normalized 8-bit floating point
* mantissa. The numbers are 32-bit fractions.
*/
-static png_uint_32
+static const png_uint_32
png_8bit_l2[128] =
{
-# ifdef PNG_DO_BC
- for (i=128;i<256;++i) { .5 - l(i/255)/l(2)*65536*65536; }
-# else
4270715492U, 4222494797U, 4174646467U, 4127164793U, 4080044201U, 4033279239U,
3986864580U, 3940795015U, 3895065449U, 3849670902U, 3804606499U, 3759867474U,
3715449162U, 3671346997U, 3627556511U, 3584073329U, 3540893168U, 3498011834U,
@@ -2203,7 +3361,6 @@ png_8bit_l2[128] = 324227938U, 298676034U, 273229066U, 247886176U, 222646516U, 197509248U,
172473545U, 147538590U, 122703574U, 97967701U, 73330182U, 48790236U,
24347096U, 0U
-# endif
#if 0
/* The following are the values for 16-bit tables - these work fine for the
@@ -2226,18 +3383,18 @@ png_8bit_l2[128] = #endif
};
-PNG_STATIC png_int_32
+static png_int_32
png_log8bit(unsigned int x)
{
unsigned int lg2 = 0;
/* Each time 'x' is multiplied by 2, 1 must be subtracted off the final log,
* because the log is actually negate that means adding 1. The final
* returned value thus has the range 0 (for 255 input) to 7.994 (for 1
- * input), return 7.99998 for the overflow (log 0) case - so the result is
+ * input), return -1 for the overflow (log 0) case, - so the result is
* always at most 19 bits.
*/
if ((x &= 0xff) == 0)
- return 0xffffffff;
+ return -1;
if ((x & 0xf0) == 0)
lg2 = 4, x <<= 4;
@@ -2282,14 +3439,14 @@ png_log8bit(unsigned int x) * Zero (257): 0
* End (258): 23499
*/
-PNG_STATIC png_int_32
+static png_int_32
png_log16bit(png_uint_32 x)
{
unsigned int lg2 = 0;
/* As above, but now the input has 16 bits. */
if ((x &= 0xffff) == 0)
- return 0xffffffff;
+ return -1;
if ((x & 0xff00) == 0)
lg2 = 8, x <<= 8;
@@ -2339,7 +3496,7 @@ png_log16bit(png_uint_32 x) * integer bits (the top 4) simply determine a shift.
*
* The worst case is the 16-bit distinction between 65535 and 65534, this
- * requires perhaps spurious accuracy in the decoding of the logarithm to
+ * requires perhaps spurious accuracty in the decoding of the logarithm to
* distinguish log2(65535/65534.5) - 10^-5 or 17 bits. There is little chance
* of getting this accuracy in practice.
*
@@ -2347,21 +3504,17 @@ png_log16bit(png_uint_32 x) * frational part of the logarithm by using an accurate 32-bit value from the
* top four fractional bits then multiplying in the remaining bits.
*/
-static png_uint_32
+static const png_uint_32
png_32bit_exp[16] =
{
-# ifdef PNG_DO_BC
- for (i=0;i<16;++i) { .5 + e(-i/16*l(2))*2^32; }
-# else
/* NOTE: the first entry is deliberately set to the maximum 32-bit value. */
4294967295U, 4112874773U, 3938502376U, 3771522796U, 3611622603U, 3458501653U,
3311872529U, 3171459999U, 3037000500U, 2908241642U, 2784941738U, 2666869345U,
2553802834U, 2445529972U, 2341847524U, 2242560872U
-# endif
};
/* Adjustment table; provided to explain the numbers in the code below. */
-#ifdef PNG_DO_BC
+#if 0
for (i=11;i>=0;--i){ print i, " ", (1 - e(-(2^i)/65536*l(2))) * 2^(32-i), "\n"}
11 44937.64284865548751208448
10 45180.98734845585101160448
@@ -2377,7 +3530,7 @@ for (i=11;i>=0;--i){ print i, " ", (1 - e(-(2^i)/65536*l(2))) * 2^(32-i), "\n"} 0 45425.85339951654943850496
#endif
-PNG_STATIC png_uint_32
+static png_uint_32
png_exp(png_fixed_point x)
{
if (x > 0 && x <= 0xfffff) /* Else overflow or zero (underflow) */
@@ -2425,7 +3578,7 @@ png_exp(png_fixed_point x) return 0;
}
-PNG_STATIC png_byte
+static png_byte
png_exp8bit(png_fixed_point lg2)
{
/* Get a 32-bit value: */
@@ -2439,7 +3592,7 @@ png_exp8bit(png_fixed_point lg2) return (png_byte)((x + 0x7fffffU) >> 24);
}
-PNG_STATIC png_uint_16
+static png_uint_16
png_exp16bit(png_fixed_point lg2)
{
/* Get a 32-bit value: */
@@ -2503,7 +3656,7 @@ png_gamma_16bit_correct(unsigned int value, png_fixed_point gamma_val) * 8-bit (as are the arguments.)
*/
png_uint_16 /* PRIVATE */
-png_gamma_correct(png_structp png_ptr, unsigned int value,
+png_gamma_correct(png_structrp png_ptr, unsigned int value,
png_fixed_point gamma_val)
{
if (png_ptr->bit_depth == 8)
@@ -2513,18 +3666,8 @@ png_gamma_correct(png_structp png_ptr, unsigned int value, return png_gamma_16bit_correct(value, gamma_val);
}
-/* This is the shared test on whether a gamma value is 'significant' - whether
- * it is worth doing gamma correction.
- */
-int /* PRIVATE */
-png_gamma_significant(png_fixed_point gamma_val)
-{
- return gamma_val < PNG_FP_1 - PNG_GAMMA_THRESHOLD_FIXED ||
- gamma_val > PNG_FP_1 + PNG_GAMMA_THRESHOLD_FIXED;
-}
-
/* Internal function to build a single 16-bit table - the table consists of
- * 'num' 256-entry subtables, where 'num' is determined by 'shift' - the amount
+ * 'num' 256 entry subtables, where 'num' is determined by 'shift' - the amount
* to shift the input values right (or 16-number_of_signifiant_bits).
*
* The caller is responsible for ensuring that the table gets cleaned up on
@@ -2532,7 +3675,7 @@ png_gamma_significant(png_fixed_point gamma_val) * should be somewhere that will be cleaned.
*/
static void
-png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable,
+png_build_16bit_table(png_structrp png_ptr, png_uint_16pp *ptable,
PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
{
/* Various values derived from 'shift': */
@@ -2542,12 +3685,12 @@ png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable, unsigned int i;
png_uint_16pp table = *ptable =
- (png_uint_16pp)png_calloc(png_ptr, num * png_sizeof(png_uint_16p));
+ (png_uint_16pp)png_calloc(png_ptr, num * (sizeof (png_uint_16p)));
for (i = 0; i < num; i++)
{
png_uint_16p sub_table = table[i] =
- (png_uint_16p)png_malloc(png_ptr, 256 * png_sizeof(png_uint_16));
+ (png_uint_16p)png_malloc(png_ptr, 256 * (sizeof (png_uint_16)));
/* The 'threshold' test is repeated here because it can arise for one of
* the 16-bit tables even if the others don't hit it.
@@ -2600,7 +3743,7 @@ png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable, * required.
*/
static void
-png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
+png_build_16to8_table(png_structrp png_ptr, png_uint_16pp *ptable,
PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
{
PNG_CONST unsigned int num = 1U << (8U - shift);
@@ -2609,15 +3752,15 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable, png_uint_32 last;
png_uint_16pp table = *ptable =
- (png_uint_16pp)png_calloc(png_ptr, num * png_sizeof(png_uint_16p));
+ (png_uint_16pp)png_calloc(png_ptr, num * (sizeof (png_uint_16p)));
- /* 'num' is the number of tables and also the number of low bits of the
- * input 16-bit value used to select a table. Each table is itself indexed
- * by the high 8 bits of the value.
+ /* 'num' is the number of tables and also the number of low bits of low
+ * bits of the input 16-bit value used to select a table. Each table is
+ * itself index by the high 8 bits of the value.
*/
for (i = 0; i < num; i++)
table[i] = (png_uint_16p)png_malloc(png_ptr,
- 256 * png_sizeof(png_uint_16));
+ 256 * (sizeof (png_uint_16)));
/* 'gamma_val' is set to the reciprocal of the value calculated above, so
* pow(out,g) is an *input* value. 'last' is the last input value set.
@@ -2664,10 +3807,10 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable, /* Build a single 8-bit table: same as the 16-bit case but much simpler (and
* typically much faster). Note that libpng currently does no sBIT processing
- * (apparently contrary to the spec) so a 256-entry table is always generated.
+ * (apparently contrary to the spec) so a 256 entry table is always generated.
*/
static void
-png_build_8bit_table(png_structp png_ptr, png_bytepp ptable,
+png_build_8bit_table(png_structrp png_ptr, png_bytepp ptable,
PNG_CONST png_fixed_point gamma_val)
{
unsigned int i;
@@ -2684,7 +3827,7 @@ png_build_8bit_table(png_structp png_ptr, png_bytepp ptable, * tables.
*/
void /* PRIVATE */
-png_destroy_gamma_table(png_structp png_ptr)
+png_destroy_gamma_table(png_structrp png_ptr)
{
png_free(png_ptr, png_ptr->gamma_table);
png_ptr->gamma_table = NULL;
@@ -2740,7 +3883,7 @@ png_destroy_gamma_table(png_structp png_ptr) * we don't need to allocate > 64K chunks for a full 16-bit table.
*/
void /* PRIVATE */
-png_build_gamma_table(png_structp png_ptr, int bit_depth)
+png_build_gamma_table(png_structrp png_ptr, int bit_depth)
{
png_debug(1, "in png_build_gamma_table");
@@ -2759,7 +3902,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth) if (bit_depth <= 8)
{
png_build_8bit_table(png_ptr, &png_ptr->gamma_table,
- png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->gamma,
+ png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->colorspace.gamma,
png_ptr->screen_gamma) : PNG_FP_1);
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
@@ -2768,11 +3911,11 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth) if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
{
png_build_8bit_table(png_ptr, &png_ptr->gamma_to_1,
- png_reciprocal(png_ptr->gamma));
+ png_reciprocal(png_ptr->colorspace.gamma));
png_build_8bit_table(png_ptr, &png_ptr->gamma_from_1,
png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
- png_ptr->gamma/* Probably doing rgb_to_gray */);
+ png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
}
#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
}
@@ -2800,7 +3943,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth) * Where 'iv' is the input color value and 'ov' is the output value -
* pow(iv, gamma).
*
- * Thus the gamma table consists of up to 256 256-entry tables. The table
+ * Thus the gamma table consists of up to 256 256 entry tables. The table
* is selected by the (8-gamma_shift) most significant of the low 8 bits of
* the color value then indexed by the upper 8 bits:
*
@@ -2841,13 +3984,13 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth) if (png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8))
#endif
png_build_16to8_table(png_ptr, &png_ptr->gamma_16_table, shift,
- png_ptr->screen_gamma > 0 ? png_product2(png_ptr->gamma,
+ png_ptr->screen_gamma > 0 ? png_product2(png_ptr->colorspace.gamma,
png_ptr->screen_gamma) : PNG_FP_1);
#ifdef PNG_16BIT_SUPPORTED
else
png_build_16bit_table(png_ptr, &png_ptr->gamma_16_table, shift,
- png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->gamma,
+ png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->colorspace.gamma,
png_ptr->screen_gamma) : PNG_FP_1);
#endif
@@ -2857,7 +4000,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth) if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
{
png_build_16bit_table(png_ptr, &png_ptr->gamma_16_to_1, shift,
- png_reciprocal(png_ptr->gamma));
+ png_reciprocal(png_ptr->colorspace.gamma));
/* Notice that the '16 from 1' table should be full precision, however
* the lookup on this table still uses gamma_shift, so it can't be.
@@ -2865,10 +4008,291 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth) */
png_build_16bit_table(png_ptr, &png_ptr->gamma_16_from_1, shift,
png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
- png_ptr->gamma/* Probably doing rgb_to_gray */);
+ png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
}
#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
}
}
#endif /* READ_GAMMA */
+
+/* HARDWARE OPTION SUPPORT */
+#ifdef PNG_SET_OPTION_SUPPORTED
+int PNGAPI
+png_set_option(png_structrp png_ptr, int option, int onoff)
+{
+ if (png_ptr != NULL && option >= 0 && option < PNG_OPTION_NEXT &&
+ (option & 1) == 0)
+ {
+ int mask = 3 << option;
+ int setting = (2 + (onoff != 0)) << option;
+ int current = png_ptr->options;
+
+ png_ptr->options = (png_byte)((current & ~mask) | setting);
+
+ return (current & mask) >> option;
+ }
+
+ return PNG_OPTION_INVALID;
+}
+#endif
+
+/* sRGB support */
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
+ defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
+/* sRGB conversion tables; these are machine generated with the code in
+ * contrib/tools/makesRGB.c. The actual sRGB transfer curve defined in the
+ * specification (see the article at http://en.wikipedia.org/wiki/SRGB)
+ * is used, not the gamma=1/2.2 approximation use elsewhere in libpng.
+ * The sRGB to linear table is exact (to the nearest 16 bit linear fraction).
+ * The inverse (linear to sRGB) table has accuracies as follows:
+ *
+ * For all possible (255*65535+1) input values:
+ *
+ * error: -0.515566 - 0.625971, 79441 (0.475369%) of readings inexact
+ *
+ * For the input values corresponding to the 65536 16-bit values:
+ *
+ * error: -0.513727 - 0.607759, 308 (0.469978%) of readings inexact
+ *
+ * In all cases the inexact readings are off by one.
+ */
+
+#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
+/* The convert-to-sRGB table is only currently required for read. */
+const png_uint_16 png_sRGB_table[256] =
+{
+ 0,20,40,60,80,99,119,139,
+ 159,179,199,219,241,264,288,313,
+ 340,367,396,427,458,491,526,562,
+ 599,637,677,718,761,805,851,898,
+ 947,997,1048,1101,1156,1212,1270,1330,
+ 1391,1453,1517,1583,1651,1720,1790,1863,
+ 1937,2013,2090,2170,2250,2333,2418,2504,
+ 2592,2681,2773,2866,2961,3058,3157,3258,
+ 3360,3464,3570,3678,3788,3900,4014,4129,
+ 4247,4366,4488,4611,4736,4864,4993,5124,
+ 5257,5392,5530,5669,5810,5953,6099,6246,
+ 6395,6547,6700,6856,7014,7174,7335,7500,
+ 7666,7834,8004,8177,8352,8528,8708,8889,
+ 9072,9258,9445,9635,9828,10022,10219,10417,
+ 10619,10822,11028,11235,11446,11658,11873,12090,
+ 12309,12530,12754,12980,13209,13440,13673,13909,
+ 14146,14387,14629,14874,15122,15371,15623,15878,
+ 16135,16394,16656,16920,17187,17456,17727,18001,
+ 18277,18556,18837,19121,19407,19696,19987,20281,
+ 20577,20876,21177,21481,21787,22096,22407,22721,
+ 23038,23357,23678,24002,24329,24658,24990,25325,
+ 25662,26001,26344,26688,27036,27386,27739,28094,
+ 28452,28813,29176,29542,29911,30282,30656,31033,
+ 31412,31794,32179,32567,32957,33350,33745,34143,
+ 34544,34948,35355,35764,36176,36591,37008,37429,
+ 37852,38278,38706,39138,39572,40009,40449,40891,
+ 41337,41785,42236,42690,43147,43606,44069,44534,
+ 45002,45473,45947,46423,46903,47385,47871,48359,
+ 48850,49344,49841,50341,50844,51349,51858,52369,
+ 52884,53401,53921,54445,54971,55500,56032,56567,
+ 57105,57646,58190,58737,59287,59840,60396,60955,
+ 61517,62082,62650,63221,63795,64372,64952,65535
+};
+
+#endif /* simplified read only */
+
+/* The base/delta tables are required for both read and write (but currently
+ * only the simplified versions.)
+ */
+const png_uint_16 png_sRGB_base[512] =
+{
+ 128,1782,3383,4644,5675,6564,7357,8074,
+ 8732,9346,9921,10463,10977,11466,11935,12384,
+ 12816,13233,13634,14024,14402,14769,15125,15473,
+ 15812,16142,16466,16781,17090,17393,17690,17981,
+ 18266,18546,18822,19093,19359,19621,19879,20133,
+ 20383,20630,20873,21113,21349,21583,21813,22041,
+ 22265,22487,22707,22923,23138,23350,23559,23767,
+ 23972,24175,24376,24575,24772,24967,25160,25352,
+ 25542,25730,25916,26101,26284,26465,26645,26823,
+ 27000,27176,27350,27523,27695,27865,28034,28201,
+ 28368,28533,28697,28860,29021,29182,29341,29500,
+ 29657,29813,29969,30123,30276,30429,30580,30730,
+ 30880,31028,31176,31323,31469,31614,31758,31902,
+ 32045,32186,32327,32468,32607,32746,32884,33021,
+ 33158,33294,33429,33564,33697,33831,33963,34095,
+ 34226,34357,34486,34616,34744,34873,35000,35127,
+ 35253,35379,35504,35629,35753,35876,35999,36122,
+ 36244,36365,36486,36606,36726,36845,36964,37083,
+ 37201,37318,37435,37551,37668,37783,37898,38013,
+ 38127,38241,38354,38467,38580,38692,38803,38915,
+ 39026,39136,39246,39356,39465,39574,39682,39790,
+ 39898,40005,40112,40219,40325,40431,40537,40642,
+ 40747,40851,40955,41059,41163,41266,41369,41471,
+ 41573,41675,41777,41878,41979,42079,42179,42279,
+ 42379,42478,42577,42676,42775,42873,42971,43068,
+ 43165,43262,43359,43456,43552,43648,43743,43839,
+ 43934,44028,44123,44217,44311,44405,44499,44592,
+ 44685,44778,44870,44962,45054,45146,45238,45329,
+ 45420,45511,45601,45692,45782,45872,45961,46051,
+ 46140,46229,46318,46406,46494,46583,46670,46758,
+ 46846,46933,47020,47107,47193,47280,47366,47452,
+ 47538,47623,47709,47794,47879,47964,48048,48133,
+ 48217,48301,48385,48468,48552,48635,48718,48801,
+ 48884,48966,49048,49131,49213,49294,49376,49458,
+ 49539,49620,49701,49782,49862,49943,50023,50103,
+ 50183,50263,50342,50422,50501,50580,50659,50738,
+ 50816,50895,50973,51051,51129,51207,51285,51362,
+ 51439,51517,51594,51671,51747,51824,51900,51977,
+ 52053,52129,52205,52280,52356,52432,52507,52582,
+ 52657,52732,52807,52881,52956,53030,53104,53178,
+ 53252,53326,53400,53473,53546,53620,53693,53766,
+ 53839,53911,53984,54056,54129,54201,54273,54345,
+ 54417,54489,54560,54632,54703,54774,54845,54916,
+ 54987,55058,55129,55199,55269,55340,55410,55480,
+ 55550,55620,55689,55759,55828,55898,55967,56036,
+ 56105,56174,56243,56311,56380,56448,56517,56585,
+ 56653,56721,56789,56857,56924,56992,57059,57127,
+ 57194,57261,57328,57395,57462,57529,57595,57662,
+ 57728,57795,57861,57927,57993,58059,58125,58191,
+ 58256,58322,58387,58453,58518,58583,58648,58713,
+ 58778,58843,58908,58972,59037,59101,59165,59230,
+ 59294,59358,59422,59486,59549,59613,59677,59740,
+ 59804,59867,59930,59993,60056,60119,60182,60245,
+ 60308,60370,60433,60495,60558,60620,60682,60744,
+ 60806,60868,60930,60992,61054,61115,61177,61238,
+ 61300,61361,61422,61483,61544,61605,61666,61727,
+ 61788,61848,61909,61969,62030,62090,62150,62211,
+ 62271,62331,62391,62450,62510,62570,62630,62689,
+ 62749,62808,62867,62927,62986,63045,63104,63163,
+ 63222,63281,63340,63398,63457,63515,63574,63632,
+ 63691,63749,63807,63865,63923,63981,64039,64097,
+ 64155,64212,64270,64328,64385,64443,64500,64557,
+ 64614,64672,64729,64786,64843,64900,64956,65013,
+ 65070,65126,65183,65239,65296,65352,65409,65465
+};
+
+const png_byte png_sRGB_delta[512] =
+{
+ 207,201,158,129,113,100,90,82,77,72,68,64,61,59,56,54,
+ 52,50,49,47,46,45,43,42,41,40,39,39,38,37,36,36,
+ 35,34,34,33,33,32,32,31,31,30,30,30,29,29,28,28,
+ 28,27,27,27,27,26,26,26,25,25,25,25,24,24,24,24,
+ 23,23,23,23,23,22,22,22,22,22,22,21,21,21,21,21,
+ 21,20,20,20,20,20,20,20,20,19,19,19,19,19,19,19,
+ 19,18,18,18,18,18,18,18,18,18,18,17,17,17,17,17,
+ 17,17,17,17,17,17,16,16,16,16,16,16,16,16,16,16,
+ 16,16,16,16,15,15,15,15,15,15,15,15,15,15,15,15,
+ 15,15,15,15,14,14,14,14,14,14,14,14,14,14,14,14,
+ 14,14,14,14,14,14,14,13,13,13,13,13,13,13,13,13,
+ 13,13,13,13,13,13,13,13,13,13,13,13,13,13,12,12,
+ 12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,
+ 12,12,12,12,12,12,12,12,12,12,12,12,11,11,11,11,
+ 11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,
+ 11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,
+ 11,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,
+ 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,
+ 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,
+ 10,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+ 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+ 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+ 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+ 9,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7
+};
+#endif /* SIMPLIFIED READ/WRITE sRGB support */
+
+/* SIMPLIFIED READ/WRITE SUPPORT */
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
+ defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
+static int
+png_image_free_function(png_voidp argument)
+{
+ png_imagep image = png_voidcast(png_imagep, argument);
+ png_controlp cp = image->opaque;
+ png_control c;
+
+ /* Double check that we have a png_ptr - it should be impossible to get here
+ * without one.
+ */
+ if (cp->png_ptr == NULL)
+ return 0;
+
+ /* First free any data held in the control structure. */
+# ifdef PNG_STDIO_SUPPORTED
+ if (cp->owned_file)
+ {
+ FILE *fp = png_voidcast(FILE*, cp->png_ptr->io_ptr);
+ cp->owned_file = 0;
+
+ /* Ignore errors here. */
+ if (fp != NULL)
+ {
+ cp->png_ptr->io_ptr = NULL;
+ (void)fclose(fp);
+ }
+ }
+# endif
+
+ /* Copy the control structure so that the original, allocated, version can be
+ * safely freed. Notice that a png_error here stops the remainder of the
+ * cleanup, but this is probably fine because that would indicate bad memory
+ * problems anyway.
+ */
+ c = *cp;
+ image->opaque = &c;
+ png_free(c.png_ptr, cp);
+
+ /* Then the structures, calling the correct API. */
+ if (c.for_write)
+ {
+# ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
+ png_destroy_write_struct(&c.png_ptr, &c.info_ptr);
+# else
+ png_error(c.png_ptr, "simplified write not supported");
+# endif
+ }
+ else
+ {
+# ifdef PNG_SIMPLIFIED_READ_SUPPORTED
+ png_destroy_read_struct(&c.png_ptr, &c.info_ptr, NULL);
+# else
+ png_error(c.png_ptr, "simplified read not supported");
+# endif
+ }
+
+ /* Success. */
+ return 1;
+}
+
+void PNGAPI
+png_image_free(png_imagep image)
+{
+ /* Safely call the real function, but only if doing so is safe at this point
+ * (if not inside an error handling context). Otherwise assume
+ * png_safe_execute will call this API after the return.
+ */
+ if (image != NULL && image->opaque != NULL &&
+ image->opaque->error_buf == NULL)
+ {
+ /* Ignore errors here: */
+ (void)png_safe_execute(image, png_image_free_function, image);
+ image->opaque = NULL;
+ }
+}
+
+int /* PRIVATE */
+png_image_error(png_imagep image, png_const_charp error_message)
+{
+ /* Utility to log an error. */
+ png_safecat(image->message, (sizeof image->message), 0, error_message);
+ image->warning_or_error |= PNG_IMAGE_ERROR;
+ png_image_free(image);
+ return 0;
+}
+
+#endif /* SIMPLIFIED READ/WRITE */
#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
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