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-rw-r--r--plugins/FreeImage/Source/LibJPEG/jfdctfst.c460
1 files changed, 230 insertions, 230 deletions
diff --git a/plugins/FreeImage/Source/LibJPEG/jfdctfst.c b/plugins/FreeImage/Source/LibJPEG/jfdctfst.c
index 82b92317b0..8cad5f2293 100644
--- a/plugins/FreeImage/Source/LibJPEG/jfdctfst.c
+++ b/plugins/FreeImage/Source/LibJPEG/jfdctfst.c
@@ -1,230 +1,230 @@
-/*
- * jfdctfst.c
- *
- * Copyright (C) 1994-1996, Thomas G. Lane.
- * Modified 2003-2009 by Guido Vollbeding.
- * This file is part of the Independent JPEG Group's software.
- * For conditions of distribution and use, see the accompanying README file.
- *
- * This file contains a fast, not so accurate integer implementation of the
- * forward DCT (Discrete Cosine Transform).
- *
- * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT
- * on each column. Direct algorithms are also available, but they are
- * much more complex and seem not to be any faster when reduced to code.
- *
- * This implementation is based on Arai, Agui, and Nakajima's algorithm for
- * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in
- * Japanese, but the algorithm is described in the Pennebaker & Mitchell
- * JPEG textbook (see REFERENCES section in file README). The following code
- * is based directly on figure 4-8 in P&M.
- * While an 8-point DCT cannot be done in less than 11 multiplies, it is
- * possible to arrange the computation so that many of the multiplies are
- * simple scalings of the final outputs. These multiplies can then be
- * folded into the multiplications or divisions by the JPEG quantization
- * table entries. The AA&N method leaves only 5 multiplies and 29 adds
- * to be done in the DCT itself.
- * The primary disadvantage of this method is that with fixed-point math,
- * accuracy is lost due to imprecise representation of the scaled
- * quantization values. The smaller the quantization table entry, the less
- * precise the scaled value, so this implementation does worse with high-
- * quality-setting files than with low-quality ones.
- */
-
-#define JPEG_INTERNALS
-#include "jinclude.h"
-#include "jpeglib.h"
-#include "jdct.h" /* Private declarations for DCT subsystem */
-
-#ifdef DCT_IFAST_SUPPORTED
-
-
-/*
- * This module is specialized to the case DCTSIZE = 8.
- */
-
-#if DCTSIZE != 8
- Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */
-#endif
-
-
-/* Scaling decisions are generally the same as in the LL&M algorithm;
- * see jfdctint.c for more details. However, we choose to descale
- * (right shift) multiplication products as soon as they are formed,
- * rather than carrying additional fractional bits into subsequent additions.
- * This compromises accuracy slightly, but it lets us save a few shifts.
- * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples)
- * everywhere except in the multiplications proper; this saves a good deal
- * of work on 16-bit-int machines.
- *
- * Again to save a few shifts, the intermediate results between pass 1 and
- * pass 2 are not upscaled, but are represented only to integral precision.
- *
- * A final compromise is to represent the multiplicative constants to only
- * 8 fractional bits, rather than 13. This saves some shifting work on some
- * machines, and may also reduce the cost of multiplication (since there
- * are fewer one-bits in the constants).
- */
-
-#define CONST_BITS 8
-
-
-/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus
- * causing a lot of useless floating-point operations at run time.
- * To get around this we use the following pre-calculated constants.
- * If you change CONST_BITS you may want to add appropriate values.
- * (With a reasonable C compiler, you can just rely on the FIX() macro...)
- */
-
-#if CONST_BITS == 8
-#define FIX_0_382683433 ((INT32) 98) /* FIX(0.382683433) */
-#define FIX_0_541196100 ((INT32) 139) /* FIX(0.541196100) */
-#define FIX_0_707106781 ((INT32) 181) /* FIX(0.707106781) */
-#define FIX_1_306562965 ((INT32) 334) /* FIX(1.306562965) */
-#else
-#define FIX_0_382683433 FIX(0.382683433)
-#define FIX_0_541196100 FIX(0.541196100)
-#define FIX_0_707106781 FIX(0.707106781)
-#define FIX_1_306562965 FIX(1.306562965)
-#endif
-
-
-/* We can gain a little more speed, with a further compromise in accuracy,
- * by omitting the addition in a descaling shift. This yields an incorrectly
- * rounded result half the time...
- */
-
-#ifndef USE_ACCURATE_ROUNDING
-#undef DESCALE
-#define DESCALE(x,n) RIGHT_SHIFT(x, n)
-#endif
-
-
-/* Multiply a DCTELEM variable by an INT32 constant, and immediately
- * descale to yield a DCTELEM result.
- */
-
-#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS))
-
-
-/*
- * Perform the forward DCT on one block of samples.
- */
-
-GLOBAL(void)
-jpeg_fdct_ifast (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
-{
- DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
- DCTELEM tmp10, tmp11, tmp12, tmp13;
- DCTELEM z1, z2, z3, z4, z5, z11, z13;
- DCTELEM *dataptr;
- JSAMPROW elemptr;
- int ctr;
- SHIFT_TEMPS
-
- /* Pass 1: process rows. */
-
- dataptr = data;
- for (ctr = 0; ctr < DCTSIZE; ctr++) {
- elemptr = sample_data[ctr] + start_col;
-
- /* Load data into workspace */
- tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[7]);
- tmp7 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[7]);
- tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[6]);
- tmp6 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[6]);
- tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[5]);
- tmp5 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[5]);
- tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[4]);
- tmp4 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[4]);
-
- /* Even part */
-
- tmp10 = tmp0 + tmp3; /* phase 2 */
- tmp13 = tmp0 - tmp3;
- tmp11 = tmp1 + tmp2;
- tmp12 = tmp1 - tmp2;
-
- /* Apply unsigned->signed conversion */
- dataptr[0] = tmp10 + tmp11 - 8 * CENTERJSAMPLE; /* phase 3 */
- dataptr[4] = tmp10 - tmp11;
-
- z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
- dataptr[2] = tmp13 + z1; /* phase 5 */
- dataptr[6] = tmp13 - z1;
-
- /* Odd part */
-
- tmp10 = tmp4 + tmp5; /* phase 2 */
- tmp11 = tmp5 + tmp6;
- tmp12 = tmp6 + tmp7;
-
- /* The rotator is modified from fig 4-8 to avoid extra negations. */
- z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
- z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
- z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
- z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
-
- z11 = tmp7 + z3; /* phase 5 */
- z13 = tmp7 - z3;
-
- dataptr[5] = z13 + z2; /* phase 6 */
- dataptr[3] = z13 - z2;
- dataptr[1] = z11 + z4;
- dataptr[7] = z11 - z4;
-
- dataptr += DCTSIZE; /* advance pointer to next row */
- }
-
- /* Pass 2: process columns. */
-
- dataptr = data;
- for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
- tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];
- tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];
- tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];
- tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];
- tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];
- tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];
- tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];
- tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];
-
- /* Even part */
-
- tmp10 = tmp0 + tmp3; /* phase 2 */
- tmp13 = tmp0 - tmp3;
- tmp11 = tmp1 + tmp2;
- tmp12 = tmp1 - tmp2;
-
- dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */
- dataptr[DCTSIZE*4] = tmp10 - tmp11;
-
- z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
- dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */
- dataptr[DCTSIZE*6] = tmp13 - z1;
-
- /* Odd part */
-
- tmp10 = tmp4 + tmp5; /* phase 2 */
- tmp11 = tmp5 + tmp6;
- tmp12 = tmp6 + tmp7;
-
- /* The rotator is modified from fig 4-8 to avoid extra negations. */
- z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
- z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
- z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
- z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
-
- z11 = tmp7 + z3; /* phase 5 */
- z13 = tmp7 - z3;
-
- dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */
- dataptr[DCTSIZE*3] = z13 - z2;
- dataptr[DCTSIZE*1] = z11 + z4;
- dataptr[DCTSIZE*7] = z11 - z4;
-
- dataptr++; /* advance pointer to next column */
- }
-}
-
-#endif /* DCT_IFAST_SUPPORTED */
+/*
+ * jfdctfst.c
+ *
+ * Copyright (C) 1994-1996, Thomas G. Lane.
+ * Modified 2003-2009 by Guido Vollbeding.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains a fast, not so accurate integer implementation of the
+ * forward DCT (Discrete Cosine Transform).
+ *
+ * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT
+ * on each column. Direct algorithms are also available, but they are
+ * much more complex and seem not to be any faster when reduced to code.
+ *
+ * This implementation is based on Arai, Agui, and Nakajima's algorithm for
+ * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in
+ * Japanese, but the algorithm is described in the Pennebaker & Mitchell
+ * JPEG textbook (see REFERENCES section in file README). The following code
+ * is based directly on figure 4-8 in P&M.
+ * While an 8-point DCT cannot be done in less than 11 multiplies, it is
+ * possible to arrange the computation so that many of the multiplies are
+ * simple scalings of the final outputs. These multiplies can then be
+ * folded into the multiplications or divisions by the JPEG quantization
+ * table entries. The AA&N method leaves only 5 multiplies and 29 adds
+ * to be done in the DCT itself.
+ * The primary disadvantage of this method is that with fixed-point math,
+ * accuracy is lost due to imprecise representation of the scaled
+ * quantization values. The smaller the quantization table entry, the less
+ * precise the scaled value, so this implementation does worse with high-
+ * quality-setting files than with low-quality ones.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jdct.h" /* Private declarations for DCT subsystem */
+
+#ifdef DCT_IFAST_SUPPORTED
+
+
+/*
+ * This module is specialized to the case DCTSIZE = 8.
+ */
+
+#if DCTSIZE != 8
+ Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */
+#endif
+
+
+/* Scaling decisions are generally the same as in the LL&M algorithm;
+ * see jfdctint.c for more details. However, we choose to descale
+ * (right shift) multiplication products as soon as they are formed,
+ * rather than carrying additional fractional bits into subsequent additions.
+ * This compromises accuracy slightly, but it lets us save a few shifts.
+ * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples)
+ * everywhere except in the multiplications proper; this saves a good deal
+ * of work on 16-bit-int machines.
+ *
+ * Again to save a few shifts, the intermediate results between pass 1 and
+ * pass 2 are not upscaled, but are represented only to integral precision.
+ *
+ * A final compromise is to represent the multiplicative constants to only
+ * 8 fractional bits, rather than 13. This saves some shifting work on some
+ * machines, and may also reduce the cost of multiplication (since there
+ * are fewer one-bits in the constants).
+ */
+
+#define CONST_BITS 8
+
+
+/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus
+ * causing a lot of useless floating-point operations at run time.
+ * To get around this we use the following pre-calculated constants.
+ * If you change CONST_BITS you may want to add appropriate values.
+ * (With a reasonable C compiler, you can just rely on the FIX() macro...)
+ */
+
+#if CONST_BITS == 8
+#define FIX_0_382683433 ((INT32) 98) /* FIX(0.382683433) */
+#define FIX_0_541196100 ((INT32) 139) /* FIX(0.541196100) */
+#define FIX_0_707106781 ((INT32) 181) /* FIX(0.707106781) */
+#define FIX_1_306562965 ((INT32) 334) /* FIX(1.306562965) */
+#else
+#define FIX_0_382683433 FIX(0.382683433)
+#define FIX_0_541196100 FIX(0.541196100)
+#define FIX_0_707106781 FIX(0.707106781)
+#define FIX_1_306562965 FIX(1.306562965)
+#endif
+
+
+/* We can gain a little more speed, with a further compromise in accuracy,
+ * by omitting the addition in a descaling shift. This yields an incorrectly
+ * rounded result half the time...
+ */
+
+#ifndef USE_ACCURATE_ROUNDING
+#undef DESCALE
+#define DESCALE(x,n) RIGHT_SHIFT(x, n)
+#endif
+
+
+/* Multiply a DCTELEM variable by an INT32 constant, and immediately
+ * descale to yield a DCTELEM result.
+ */
+
+#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS))
+
+
+/*
+ * Perform the forward DCT on one block of samples.
+ */
+
+GLOBAL(void)
+jpeg_fdct_ifast (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
+{
+ DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
+ DCTELEM tmp10, tmp11, tmp12, tmp13;
+ DCTELEM z1, z2, z3, z4, z5, z11, z13;
+ DCTELEM *dataptr;
+ JSAMPROW elemptr;
+ int ctr;
+ SHIFT_TEMPS
+
+ /* Pass 1: process rows. */
+
+ dataptr = data;
+ for (ctr = 0; ctr < DCTSIZE; ctr++) {
+ elemptr = sample_data[ctr] + start_col;
+
+ /* Load data into workspace */
+ tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[7]);
+ tmp7 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[7]);
+ tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[6]);
+ tmp6 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[6]);
+ tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[5]);
+ tmp5 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[5]);
+ tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[4]);
+ tmp4 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[4]);
+
+ /* Even part */
+
+ tmp10 = tmp0 + tmp3; /* phase 2 */
+ tmp13 = tmp0 - tmp3;
+ tmp11 = tmp1 + tmp2;
+ tmp12 = tmp1 - tmp2;
+
+ /* Apply unsigned->signed conversion */
+ dataptr[0] = tmp10 + tmp11 - 8 * CENTERJSAMPLE; /* phase 3 */
+ dataptr[4] = tmp10 - tmp11;
+
+ z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
+ dataptr[2] = tmp13 + z1; /* phase 5 */
+ dataptr[6] = tmp13 - z1;
+
+ /* Odd part */
+
+ tmp10 = tmp4 + tmp5; /* phase 2 */
+ tmp11 = tmp5 + tmp6;
+ tmp12 = tmp6 + tmp7;
+
+ /* The rotator is modified from fig 4-8 to avoid extra negations. */
+ z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
+ z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
+ z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
+ z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
+
+ z11 = tmp7 + z3; /* phase 5 */
+ z13 = tmp7 - z3;
+
+ dataptr[5] = z13 + z2; /* phase 6 */
+ dataptr[3] = z13 - z2;
+ dataptr[1] = z11 + z4;
+ dataptr[7] = z11 - z4;
+
+ dataptr += DCTSIZE; /* advance pointer to next row */
+ }
+
+ /* Pass 2: process columns. */
+
+ dataptr = data;
+ for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
+ tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];
+ tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];
+ tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];
+ tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];
+ tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];
+ tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];
+ tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];
+ tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];
+
+ /* Even part */
+
+ tmp10 = tmp0 + tmp3; /* phase 2 */
+ tmp13 = tmp0 - tmp3;
+ tmp11 = tmp1 + tmp2;
+ tmp12 = tmp1 - tmp2;
+
+ dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */
+ dataptr[DCTSIZE*4] = tmp10 - tmp11;
+
+ z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
+ dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */
+ dataptr[DCTSIZE*6] = tmp13 - z1;
+
+ /* Odd part */
+
+ tmp10 = tmp4 + tmp5; /* phase 2 */
+ tmp11 = tmp5 + tmp6;
+ tmp12 = tmp6 + tmp7;
+
+ /* The rotator is modified from fig 4-8 to avoid extra negations. */
+ z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
+ z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
+ z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
+ z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
+
+ z11 = tmp7 + z3; /* phase 5 */
+ z13 = tmp7 - z3;
+
+ dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */
+ dataptr[DCTSIZE*3] = z13 - z2;
+ dataptr[DCTSIZE*1] = z11 + z4;
+ dataptr[DCTSIZE*7] = z11 - z4;
+
+ dataptr++; /* advance pointer to next column */
+ }
+}
+
+#endif /* DCT_IFAST_SUPPORTED */