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-rw-r--r--plugins/FreeImage/Source/LibJPEG/jidctflt.c470
1 files changed, 235 insertions, 235 deletions
diff --git a/plugins/FreeImage/Source/LibJPEG/jidctflt.c b/plugins/FreeImage/Source/LibJPEG/jidctflt.c
index f399600c89..23ae9d333b 100644
--- a/plugins/FreeImage/Source/LibJPEG/jidctflt.c
+++ b/plugins/FreeImage/Source/LibJPEG/jidctflt.c
@@ -1,235 +1,235 @@
-/*
- * jidctflt.c
- *
- * Copyright (C) 1994-1998, Thomas G. Lane.
- * Modified 2010 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 floating-point implementation of the
- * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine
- * must also perform dequantization of the input coefficients.
- *
- * This implementation should be more accurate than either of the integer
- * IDCT implementations. However, it may not give the same results on all
- * machines because of differences in roundoff behavior. Speed will depend
- * on the hardware's floating point capacity.
- *
- * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT
- * on each row (or vice versa, but it's more convenient to emit a row at
- * a time). 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 a fixed-point
- * implementation, accuracy is lost due to imprecise representation of the
- * scaled quantization values. However, that problem does not arise if
- * we use floating point arithmetic.
- */
-
-#define JPEG_INTERNALS
-#include "jinclude.h"
-#include "jpeglib.h"
-#include "jdct.h" /* Private declarations for DCT subsystem */
-
-#ifdef DCT_FLOAT_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
-
-
-/* Dequantize a coefficient by multiplying it by the multiplier-table
- * entry; produce a float result.
- */
-
-#define DEQUANTIZE(coef,quantval) (((FAST_FLOAT) (coef)) * (quantval))
-
-
-/*
- * Perform dequantization and inverse DCT on one block of coefficients.
- */
-
-GLOBAL(void)
-jpeg_idct_float (j_decompress_ptr cinfo, jpeg_component_info * compptr,
- JCOEFPTR coef_block,
- JSAMPARRAY output_buf, JDIMENSION output_col)
-{
- FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
- FAST_FLOAT tmp10, tmp11, tmp12, tmp13;
- FAST_FLOAT z5, z10, z11, z12, z13;
- JCOEFPTR inptr;
- FLOAT_MULT_TYPE * quantptr;
- FAST_FLOAT * wsptr;
- JSAMPROW outptr;
- JSAMPLE *range_limit = cinfo->sample_range_limit;
- int ctr;
- FAST_FLOAT workspace[DCTSIZE2]; /* buffers data between passes */
-
- /* Pass 1: process columns from input, store into work array. */
-
- inptr = coef_block;
- quantptr = (FLOAT_MULT_TYPE *) compptr->dct_table;
- wsptr = workspace;
- for (ctr = DCTSIZE; ctr > 0; ctr--) {
- /* Due to quantization, we will usually find that many of the input
- * coefficients are zero, especially the AC terms. We can exploit this
- * by short-circuiting the IDCT calculation for any column in which all
- * the AC terms are zero. In that case each output is equal to the
- * DC coefficient (with scale factor as needed).
- * With typical images and quantization tables, half or more of the
- * column DCT calculations can be simplified this way.
- */
-
- if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
- inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
- inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
- inptr[DCTSIZE*7] == 0) {
- /* AC terms all zero */
- FAST_FLOAT dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
-
- wsptr[DCTSIZE*0] = dcval;
- wsptr[DCTSIZE*1] = dcval;
- wsptr[DCTSIZE*2] = dcval;
- wsptr[DCTSIZE*3] = dcval;
- wsptr[DCTSIZE*4] = dcval;
- wsptr[DCTSIZE*5] = dcval;
- wsptr[DCTSIZE*6] = dcval;
- wsptr[DCTSIZE*7] = dcval;
-
- inptr++; /* advance pointers to next column */
- quantptr++;
- wsptr++;
- continue;
- }
-
- /* Even part */
-
- tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
- tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
- tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
- tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
-
- tmp10 = tmp0 + tmp2; /* phase 3 */
- tmp11 = tmp0 - tmp2;
-
- tmp13 = tmp1 + tmp3; /* phases 5-3 */
- tmp12 = (tmp1 - tmp3) * ((FAST_FLOAT) 1.414213562) - tmp13; /* 2*c4 */
-
- tmp0 = tmp10 + tmp13; /* phase 2 */
- tmp3 = tmp10 - tmp13;
- tmp1 = tmp11 + tmp12;
- tmp2 = tmp11 - tmp12;
-
- /* Odd part */
-
- tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
- tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
- tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
- tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
-
- z13 = tmp6 + tmp5; /* phase 6 */
- z10 = tmp6 - tmp5;
- z11 = tmp4 + tmp7;
- z12 = tmp4 - tmp7;
-
- tmp7 = z11 + z13; /* phase 5 */
- tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562); /* 2*c4 */
-
- z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */
- tmp10 = z5 - z12 * ((FAST_FLOAT) 1.082392200); /* 2*(c2-c6) */
- tmp12 = z5 - z10 * ((FAST_FLOAT) 2.613125930); /* 2*(c2+c6) */
-
- tmp6 = tmp12 - tmp7; /* phase 2 */
- tmp5 = tmp11 - tmp6;
- tmp4 = tmp10 - tmp5;
-
- wsptr[DCTSIZE*0] = tmp0 + tmp7;
- wsptr[DCTSIZE*7] = tmp0 - tmp7;
- wsptr[DCTSIZE*1] = tmp1 + tmp6;
- wsptr[DCTSIZE*6] = tmp1 - tmp6;
- wsptr[DCTSIZE*2] = tmp2 + tmp5;
- wsptr[DCTSIZE*5] = tmp2 - tmp5;
- wsptr[DCTSIZE*3] = tmp3 + tmp4;
- wsptr[DCTSIZE*4] = tmp3 - tmp4;
-
- inptr++; /* advance pointers to next column */
- quantptr++;
- wsptr++;
- }
-
- /* Pass 2: process rows from work array, store into output array. */
-
- wsptr = workspace;
- for (ctr = 0; ctr < DCTSIZE; ctr++) {
- outptr = output_buf[ctr] + output_col;
- /* Rows of zeroes can be exploited in the same way as we did with columns.
- * However, the column calculation has created many nonzero AC terms, so
- * the simplification applies less often (typically 5% to 10% of the time).
- * And testing floats for zero is relatively expensive, so we don't bother.
- */
-
- /* Even part */
-
- /* Apply signed->unsigned and prepare float->int conversion */
- z5 = wsptr[0] + ((FAST_FLOAT) CENTERJSAMPLE + (FAST_FLOAT) 0.5);
- tmp10 = z5 + wsptr[4];
- tmp11 = z5 - wsptr[4];
-
- tmp13 = wsptr[2] + wsptr[6];
- tmp12 = (wsptr[2] - wsptr[6]) * ((FAST_FLOAT) 1.414213562) - tmp13;
-
- tmp0 = tmp10 + tmp13;
- tmp3 = tmp10 - tmp13;
- tmp1 = tmp11 + tmp12;
- tmp2 = tmp11 - tmp12;
-
- /* Odd part */
-
- z13 = wsptr[5] + wsptr[3];
- z10 = wsptr[5] - wsptr[3];
- z11 = wsptr[1] + wsptr[7];
- z12 = wsptr[1] - wsptr[7];
-
- tmp7 = z11 + z13;
- tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562);
-
- z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */
- tmp10 = z5 - z12 * ((FAST_FLOAT) 1.082392200); /* 2*(c2-c6) */
- tmp12 = z5 - z10 * ((FAST_FLOAT) 2.613125930); /* 2*(c2+c6) */
-
- tmp6 = tmp12 - tmp7;
- tmp5 = tmp11 - tmp6;
- tmp4 = tmp10 - tmp5;
-
- /* Final output stage: float->int conversion and range-limit */
-
- outptr[0] = range_limit[((int) (tmp0 + tmp7)) & RANGE_MASK];
- outptr[7] = range_limit[((int) (tmp0 - tmp7)) & RANGE_MASK];
- outptr[1] = range_limit[((int) (tmp1 + tmp6)) & RANGE_MASK];
- outptr[6] = range_limit[((int) (tmp1 - tmp6)) & RANGE_MASK];
- outptr[2] = range_limit[((int) (tmp2 + tmp5)) & RANGE_MASK];
- outptr[5] = range_limit[((int) (tmp2 - tmp5)) & RANGE_MASK];
- outptr[3] = range_limit[((int) (tmp3 + tmp4)) & RANGE_MASK];
- outptr[4] = range_limit[((int) (tmp3 - tmp4)) & RANGE_MASK];
-
- wsptr += DCTSIZE; /* advance pointer to next row */
- }
-}
-
-#endif /* DCT_FLOAT_SUPPORTED */
+/*
+ * jidctflt.c
+ *
+ * Copyright (C) 1994-1998, Thomas G. Lane.
+ * Modified 2010 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 floating-point implementation of the
+ * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine
+ * must also perform dequantization of the input coefficients.
+ *
+ * This implementation should be more accurate than either of the integer
+ * IDCT implementations. However, it may not give the same results on all
+ * machines because of differences in roundoff behavior. Speed will depend
+ * on the hardware's floating point capacity.
+ *
+ * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT
+ * on each row (or vice versa, but it's more convenient to emit a row at
+ * a time). 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 a fixed-point
+ * implementation, accuracy is lost due to imprecise representation of the
+ * scaled quantization values. However, that problem does not arise if
+ * we use floating point arithmetic.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jdct.h" /* Private declarations for DCT subsystem */
+
+#ifdef DCT_FLOAT_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
+
+
+/* Dequantize a coefficient by multiplying it by the multiplier-table
+ * entry; produce a float result.
+ */
+
+#define DEQUANTIZE(coef,quantval) (((FAST_FLOAT) (coef)) * (quantval))
+
+
+/*
+ * Perform dequantization and inverse DCT on one block of coefficients.
+ */
+
+GLOBAL(void)
+jpeg_idct_float (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+ JCOEFPTR coef_block,
+ JSAMPARRAY output_buf, JDIMENSION output_col)
+{
+ FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
+ FAST_FLOAT tmp10, tmp11, tmp12, tmp13;
+ FAST_FLOAT z5, z10, z11, z12, z13;
+ JCOEFPTR inptr;
+ FLOAT_MULT_TYPE * quantptr;
+ FAST_FLOAT * wsptr;
+ JSAMPROW outptr;
+ JSAMPLE *range_limit = cinfo->sample_range_limit;
+ int ctr;
+ FAST_FLOAT workspace[DCTSIZE2]; /* buffers data between passes */
+
+ /* Pass 1: process columns from input, store into work array. */
+
+ inptr = coef_block;
+ quantptr = (FLOAT_MULT_TYPE *) compptr->dct_table;
+ wsptr = workspace;
+ for (ctr = DCTSIZE; ctr > 0; ctr--) {
+ /* Due to quantization, we will usually find that many of the input
+ * coefficients are zero, especially the AC terms. We can exploit this
+ * by short-circuiting the IDCT calculation for any column in which all
+ * the AC terms are zero. In that case each output is equal to the
+ * DC coefficient (with scale factor as needed).
+ * With typical images and quantization tables, half or more of the
+ * column DCT calculations can be simplified this way.
+ */
+
+ if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
+ inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
+ inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
+ inptr[DCTSIZE*7] == 0) {
+ /* AC terms all zero */
+ FAST_FLOAT dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
+
+ wsptr[DCTSIZE*0] = dcval;
+ wsptr[DCTSIZE*1] = dcval;
+ wsptr[DCTSIZE*2] = dcval;
+ wsptr[DCTSIZE*3] = dcval;
+ wsptr[DCTSIZE*4] = dcval;
+ wsptr[DCTSIZE*5] = dcval;
+ wsptr[DCTSIZE*6] = dcval;
+ wsptr[DCTSIZE*7] = dcval;
+
+ inptr++; /* advance pointers to next column */
+ quantptr++;
+ wsptr++;
+ continue;
+ }
+
+ /* Even part */
+
+ tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
+ tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
+ tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
+ tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
+
+ tmp10 = tmp0 + tmp2; /* phase 3 */
+ tmp11 = tmp0 - tmp2;
+
+ tmp13 = tmp1 + tmp3; /* phases 5-3 */
+ tmp12 = (tmp1 - tmp3) * ((FAST_FLOAT) 1.414213562) - tmp13; /* 2*c4 */
+
+ tmp0 = tmp10 + tmp13; /* phase 2 */
+ tmp3 = tmp10 - tmp13;
+ tmp1 = tmp11 + tmp12;
+ tmp2 = tmp11 - tmp12;
+
+ /* Odd part */
+
+ tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
+ tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
+ tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
+ tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
+
+ z13 = tmp6 + tmp5; /* phase 6 */
+ z10 = tmp6 - tmp5;
+ z11 = tmp4 + tmp7;
+ z12 = tmp4 - tmp7;
+
+ tmp7 = z11 + z13; /* phase 5 */
+ tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562); /* 2*c4 */
+
+ z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */
+ tmp10 = z5 - z12 * ((FAST_FLOAT) 1.082392200); /* 2*(c2-c6) */
+ tmp12 = z5 - z10 * ((FAST_FLOAT) 2.613125930); /* 2*(c2+c6) */
+
+ tmp6 = tmp12 - tmp7; /* phase 2 */
+ tmp5 = tmp11 - tmp6;
+ tmp4 = tmp10 - tmp5;
+
+ wsptr[DCTSIZE*0] = tmp0 + tmp7;
+ wsptr[DCTSIZE*7] = tmp0 - tmp7;
+ wsptr[DCTSIZE*1] = tmp1 + tmp6;
+ wsptr[DCTSIZE*6] = tmp1 - tmp6;
+ wsptr[DCTSIZE*2] = tmp2 + tmp5;
+ wsptr[DCTSIZE*5] = tmp2 - tmp5;
+ wsptr[DCTSIZE*3] = tmp3 + tmp4;
+ wsptr[DCTSIZE*4] = tmp3 - tmp4;
+
+ inptr++; /* advance pointers to next column */
+ quantptr++;
+ wsptr++;
+ }
+
+ /* Pass 2: process rows from work array, store into output array. */
+
+ wsptr = workspace;
+ for (ctr = 0; ctr < DCTSIZE; ctr++) {
+ outptr = output_buf[ctr] + output_col;
+ /* Rows of zeroes can be exploited in the same way as we did with columns.
+ * However, the column calculation has created many nonzero AC terms, so
+ * the simplification applies less often (typically 5% to 10% of the time).
+ * And testing floats for zero is relatively expensive, so we don't bother.
+ */
+
+ /* Even part */
+
+ /* Apply signed->unsigned and prepare float->int conversion */
+ z5 = wsptr[0] + ((FAST_FLOAT) CENTERJSAMPLE + (FAST_FLOAT) 0.5);
+ tmp10 = z5 + wsptr[4];
+ tmp11 = z5 - wsptr[4];
+
+ tmp13 = wsptr[2] + wsptr[6];
+ tmp12 = (wsptr[2] - wsptr[6]) * ((FAST_FLOAT) 1.414213562) - tmp13;
+
+ tmp0 = tmp10 + tmp13;
+ tmp3 = tmp10 - tmp13;
+ tmp1 = tmp11 + tmp12;
+ tmp2 = tmp11 - tmp12;
+
+ /* Odd part */
+
+ z13 = wsptr[5] + wsptr[3];
+ z10 = wsptr[5] - wsptr[3];
+ z11 = wsptr[1] + wsptr[7];
+ z12 = wsptr[1] - wsptr[7];
+
+ tmp7 = z11 + z13;
+ tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562);
+
+ z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */
+ tmp10 = z5 - z12 * ((FAST_FLOAT) 1.082392200); /* 2*(c2-c6) */
+ tmp12 = z5 - z10 * ((FAST_FLOAT) 2.613125930); /* 2*(c2+c6) */
+
+ tmp6 = tmp12 - tmp7;
+ tmp5 = tmp11 - tmp6;
+ tmp4 = tmp10 - tmp5;
+
+ /* Final output stage: float->int conversion and range-limit */
+
+ outptr[0] = range_limit[((int) (tmp0 + tmp7)) & RANGE_MASK];
+ outptr[7] = range_limit[((int) (tmp0 - tmp7)) & RANGE_MASK];
+ outptr[1] = range_limit[((int) (tmp1 + tmp6)) & RANGE_MASK];
+ outptr[6] = range_limit[((int) (tmp1 - tmp6)) & RANGE_MASK];
+ outptr[2] = range_limit[((int) (tmp2 + tmp5)) & RANGE_MASK];
+ outptr[5] = range_limit[((int) (tmp2 - tmp5)) & RANGE_MASK];
+ outptr[3] = range_limit[((int) (tmp3 + tmp4)) & RANGE_MASK];
+ outptr[4] = range_limit[((int) (tmp3 - tmp4)) & RANGE_MASK];
+
+ wsptr += DCTSIZE; /* advance pointer to next row */
+ }
+}
+
+#endif /* DCT_FLOAT_SUPPORTED */
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-19 22:37:44 +0000