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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /media/libjpeg/jcdctmgr.c
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'media/libjpeg/jcdctmgr.c')
-rw-r--r--media/libjpeg/jcdctmgr.c720
1 files changed, 720 insertions, 0 deletions
diff --git a/media/libjpeg/jcdctmgr.c b/media/libjpeg/jcdctmgr.c
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+/*
+ * jcdctmgr.c
+ *
+ * This file was part of the Independent JPEG Group's software:
+ * Copyright (C) 1994-1996, Thomas G. Lane.
+ * libjpeg-turbo Modifications:
+ * Copyright (C) 1999-2006, MIYASAKA Masaru.
+ * Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
+ * Copyright (C) 2011, 2014-2015, D. R. Commander.
+ * For conditions of distribution and use, see the accompanying README.ijg
+ * file.
+ *
+ * This file contains the forward-DCT management logic.
+ * This code selects a particular DCT implementation to be used,
+ * and it performs related housekeeping chores including coefficient
+ * quantization.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jdct.h" /* Private declarations for DCT subsystem */
+#include "jsimddct.h"
+
+
+/* Private subobject for this module */
+
+typedef void (*forward_DCT_method_ptr) (DCTELEM *data);
+typedef void (*float_DCT_method_ptr) (FAST_FLOAT *data);
+
+typedef void (*convsamp_method_ptr) (JSAMPARRAY sample_data,
+ JDIMENSION start_col,
+ DCTELEM *workspace);
+typedef void (*float_convsamp_method_ptr) (JSAMPARRAY sample_data,
+ JDIMENSION start_col,
+ FAST_FLOAT *workspace);
+
+typedef void (*quantize_method_ptr) (JCOEFPTR coef_block, DCTELEM *divisors,
+ DCTELEM *workspace);
+typedef void (*float_quantize_method_ptr) (JCOEFPTR coef_block,
+ FAST_FLOAT *divisors,
+ FAST_FLOAT *workspace);
+
+METHODDEF(void) quantize(JCOEFPTR, DCTELEM *, DCTELEM *);
+
+typedef struct {
+ struct jpeg_forward_dct pub; /* public fields */
+
+ /* Pointer to the DCT routine actually in use */
+ forward_DCT_method_ptr dct;
+ convsamp_method_ptr convsamp;
+ quantize_method_ptr quantize;
+
+ /* The actual post-DCT divisors --- not identical to the quant table
+ * entries, because of scaling (especially for an unnormalized DCT).
+ * Each table is given in normal array order.
+ */
+ DCTELEM *divisors[NUM_QUANT_TBLS];
+
+ /* work area for FDCT subroutine */
+ DCTELEM *workspace;
+
+#ifdef DCT_FLOAT_SUPPORTED
+ /* Same as above for the floating-point case. */
+ float_DCT_method_ptr float_dct;
+ float_convsamp_method_ptr float_convsamp;
+ float_quantize_method_ptr float_quantize;
+ FAST_FLOAT *float_divisors[NUM_QUANT_TBLS];
+ FAST_FLOAT *float_workspace;
+#endif
+} my_fdct_controller;
+
+typedef my_fdct_controller *my_fdct_ptr;
+
+
+#if BITS_IN_JSAMPLE == 8
+
+/*
+ * Find the highest bit in an integer through binary search.
+ */
+
+LOCAL(int)
+flss(UINT16 val)
+{
+ int bit;
+
+ bit = 16;
+
+ if (!val)
+ return 0;
+
+ if (!(val & 0xff00)) {
+ bit -= 8;
+ val <<= 8;
+ }
+ if (!(val & 0xf000)) {
+ bit -= 4;
+ val <<= 4;
+ }
+ if (!(val & 0xc000)) {
+ bit -= 2;
+ val <<= 2;
+ }
+ if (!(val & 0x8000)) {
+ bit -= 1;
+ val <<= 1;
+ }
+
+ return bit;
+}
+
+
+/*
+ * Compute values to do a division using reciprocal.
+ *
+ * This implementation is based on an algorithm described in
+ * "How to optimize for the Pentium family of microprocessors"
+ * (http://www.agner.org/assem/).
+ * More information about the basic algorithm can be found in
+ * the paper "Integer Division Using Reciprocals" by Robert Alverson.
+ *
+ * The basic idea is to replace x/d by x * d^-1. In order to store
+ * d^-1 with enough precision we shift it left a few places. It turns
+ * out that this algoright gives just enough precision, and also fits
+ * into DCTELEM:
+ *
+ * b = (the number of significant bits in divisor) - 1
+ * r = (word size) + b
+ * f = 2^r / divisor
+ *
+ * f will not be an integer for most cases, so we need to compensate
+ * for the rounding error introduced:
+ *
+ * no fractional part:
+ *
+ * result = input >> r
+ *
+ * fractional part of f < 0.5:
+ *
+ * round f down to nearest integer
+ * result = ((input + 1) * f) >> r
+ *
+ * fractional part of f > 0.5:
+ *
+ * round f up to nearest integer
+ * result = (input * f) >> r
+ *
+ * This is the original algorithm that gives truncated results. But we
+ * want properly rounded results, so we replace "input" with
+ * "input + divisor/2".
+ *
+ * In order to allow SIMD implementations we also tweak the values to
+ * allow the same calculation to be made at all times:
+ *
+ * dctbl[0] = f rounded to nearest integer
+ * dctbl[1] = divisor / 2 (+ 1 if fractional part of f < 0.5)
+ * dctbl[2] = 1 << ((word size) * 2 - r)
+ * dctbl[3] = r - (word size)
+ *
+ * dctbl[2] is for stupid instruction sets where the shift operation
+ * isn't member wise (e.g. MMX).
+ *
+ * The reason dctbl[2] and dctbl[3] reduce the shift with (word size)
+ * is that most SIMD implementations have a "multiply and store top
+ * half" operation.
+ *
+ * Lastly, we store each of the values in their own table instead
+ * of in a consecutive manner, yet again in order to allow SIMD
+ * routines.
+ */
+
+LOCAL(int)
+compute_reciprocal(UINT16 divisor, DCTELEM *dtbl)
+{
+ UDCTELEM2 fq, fr;
+ UDCTELEM c;
+ int b, r;
+
+ if (divisor == 1) {
+ /* divisor == 1 means unquantized, so these reciprocal/correction/shift
+ * values will cause the C quantization algorithm to act like the
+ * identity function. Since only the C quantization algorithm is used in
+ * these cases, the scale value is irrelevant.
+ */
+ dtbl[DCTSIZE2 * 0] = (DCTELEM)1; /* reciprocal */
+ dtbl[DCTSIZE2 * 1] = (DCTELEM)0; /* correction */
+ dtbl[DCTSIZE2 * 2] = (DCTELEM)1; /* scale */
+ dtbl[DCTSIZE2 * 3] = -(DCTELEM)(sizeof(DCTELEM) * 8); /* shift */
+ return 0;
+ }
+
+ b = flss(divisor) - 1;
+ r = sizeof(DCTELEM) * 8 + b;
+
+ fq = ((UDCTELEM2)1 << r) / divisor;
+ fr = ((UDCTELEM2)1 << r) % divisor;
+
+ c = divisor / 2; /* for rounding */
+
+ if (fr == 0) { /* divisor is power of two */
+ /* fq will be one bit too large to fit in DCTELEM, so adjust */
+ fq >>= 1;
+ r--;
+ } else if (fr <= (divisor / 2U)) { /* fractional part is < 0.5 */
+ c++;
+ } else { /* fractional part is > 0.5 */
+ fq++;
+ }
+
+ dtbl[DCTSIZE2 * 0] = (DCTELEM)fq; /* reciprocal */
+ dtbl[DCTSIZE2 * 1] = (DCTELEM)c; /* correction + roundfactor */
+#ifdef WITH_SIMD
+ dtbl[DCTSIZE2 * 2] = (DCTELEM)(1 << (sizeof(DCTELEM) * 8 * 2 - r)); /* scale */
+#else
+ dtbl[DCTSIZE2 * 2] = 1;
+#endif
+ dtbl[DCTSIZE2 * 3] = (DCTELEM)r - sizeof(DCTELEM) * 8; /* shift */
+
+ if (r <= 16) return 0;
+ else return 1;
+}
+
+#endif
+
+
+/*
+ * Initialize for a processing pass.
+ * Verify that all referenced Q-tables are present, and set up
+ * the divisor table for each one.
+ * In the current implementation, DCT of all components is done during
+ * the first pass, even if only some components will be output in the
+ * first scan. Hence all components should be examined here.
+ */
+
+METHODDEF(void)
+start_pass_fdctmgr(j_compress_ptr cinfo)
+{
+ my_fdct_ptr fdct = (my_fdct_ptr)cinfo->fdct;
+ int ci, qtblno, i;
+ jpeg_component_info *compptr;
+ JQUANT_TBL *qtbl;
+ DCTELEM *dtbl;
+
+ for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+ ci++, compptr++) {
+ qtblno = compptr->quant_tbl_no;
+ /* Make sure specified quantization table is present */
+ if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||
+ cinfo->quant_tbl_ptrs[qtblno] == NULL)
+ ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);
+ qtbl = cinfo->quant_tbl_ptrs[qtblno];
+ /* Compute divisors for this quant table */
+ /* We may do this more than once for same table, but it's not a big deal */
+ switch (cinfo->dct_method) {
+#ifdef DCT_ISLOW_SUPPORTED
+ case JDCT_ISLOW:
+ /* For LL&M IDCT method, divisors are equal to raw quantization
+ * coefficients multiplied by 8 (to counteract scaling).
+ */
+ if (fdct->divisors[qtblno] == NULL) {
+ fdct->divisors[qtblno] = (DCTELEM *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ (DCTSIZE2 * 4) * sizeof(DCTELEM));
+ }
+ dtbl = fdct->divisors[qtblno];
+ for (i = 0; i < DCTSIZE2; i++) {
+#if BITS_IN_JSAMPLE == 8
+ if (!compute_reciprocal(qtbl->quantval[i] << 3, &dtbl[i]) &&
+ fdct->quantize == jsimd_quantize)
+ fdct->quantize = quantize;
+#else
+ dtbl[i] = ((DCTELEM)qtbl->quantval[i]) << 3;
+#endif
+ }
+ break;
+#endif
+#ifdef DCT_IFAST_SUPPORTED
+ case JDCT_IFAST:
+ {
+ /* For AA&N IDCT method, divisors are equal to quantization
+ * coefficients scaled by scalefactor[row]*scalefactor[col], where
+ * scalefactor[0] = 1
+ * scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7
+ * We apply a further scale factor of 8.
+ */
+#define CONST_BITS 14
+ static const INT16 aanscales[DCTSIZE2] = {
+ /* precomputed values scaled up by 14 bits */
+ 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
+ 22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270,
+ 21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906,
+ 19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315,
+ 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
+ 12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552,
+ 8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446,
+ 4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247
+ };
+ SHIFT_TEMPS
+
+ if (fdct->divisors[qtblno] == NULL) {
+ fdct->divisors[qtblno] = (DCTELEM *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ (DCTSIZE2 * 4) * sizeof(DCTELEM));
+ }
+ dtbl = fdct->divisors[qtblno];
+ for (i = 0; i < DCTSIZE2; i++) {
+#if BITS_IN_JSAMPLE == 8
+ if (!compute_reciprocal(
+ DESCALE(MULTIPLY16V16((JLONG)qtbl->quantval[i],
+ (JLONG)aanscales[i]),
+ CONST_BITS - 3), &dtbl[i]) &&
+ fdct->quantize == jsimd_quantize)
+ fdct->quantize = quantize;
+#else
+ dtbl[i] = (DCTELEM)
+ DESCALE(MULTIPLY16V16((JLONG)qtbl->quantval[i],
+ (JLONG)aanscales[i]),
+ CONST_BITS - 3);
+#endif
+ }
+ }
+ break;
+#endif
+#ifdef DCT_FLOAT_SUPPORTED
+ case JDCT_FLOAT:
+ {
+ /* For float AA&N IDCT method, divisors are equal to quantization
+ * coefficients scaled by scalefactor[row]*scalefactor[col], where
+ * scalefactor[0] = 1
+ * scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7
+ * We apply a further scale factor of 8.
+ * What's actually stored is 1/divisor so that the inner loop can
+ * use a multiplication rather than a division.
+ */
+ FAST_FLOAT *fdtbl;
+ int row, col;
+ static const double aanscalefactor[DCTSIZE] = {
+ 1.0, 1.387039845, 1.306562965, 1.175875602,
+ 1.0, 0.785694958, 0.541196100, 0.275899379
+ };
+
+ if (fdct->float_divisors[qtblno] == NULL) {
+ fdct->float_divisors[qtblno] = (FAST_FLOAT *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ DCTSIZE2 * sizeof(FAST_FLOAT));
+ }
+ fdtbl = fdct->float_divisors[qtblno];
+ i = 0;
+ for (row = 0; row < DCTSIZE; row++) {
+ for (col = 0; col < DCTSIZE; col++) {
+ fdtbl[i] = (FAST_FLOAT)
+ (1.0 / (((double)qtbl->quantval[i] *
+ aanscalefactor[row] * aanscalefactor[col] * 8.0)));
+ i++;
+ }
+ }
+ }
+ break;
+#endif
+ default:
+ ERREXIT(cinfo, JERR_NOT_COMPILED);
+ break;
+ }
+ }
+}
+
+
+/*
+ * Load data into workspace, applying unsigned->signed conversion.
+ */
+
+METHODDEF(void)
+convsamp(JSAMPARRAY sample_data, JDIMENSION start_col, DCTELEM *workspace)
+{
+ register DCTELEM *workspaceptr;
+ register JSAMPROW elemptr;
+ register int elemr;
+
+ workspaceptr = workspace;
+ for (elemr = 0; elemr < DCTSIZE; elemr++) {
+ elemptr = sample_data[elemr] + start_col;
+
+#if DCTSIZE == 8 /* unroll the inner loop */
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+#else
+ {
+ register int elemc;
+ for (elemc = DCTSIZE; elemc > 0; elemc--)
+ *workspaceptr++ = (*elemptr++) - CENTERJSAMPLE;
+ }
+#endif
+ }
+}
+
+
+/*
+ * Quantize/descale the coefficients, and store into coef_blocks[].
+ */
+
+METHODDEF(void)
+quantize(JCOEFPTR coef_block, DCTELEM *divisors, DCTELEM *workspace)
+{
+ int i;
+ DCTELEM temp;
+ JCOEFPTR output_ptr = coef_block;
+
+#if BITS_IN_JSAMPLE == 8
+
+ UDCTELEM recip, corr;
+ int shift;
+ UDCTELEM2 product;
+
+ for (i = 0; i < DCTSIZE2; i++) {
+ temp = workspace[i];
+ recip = divisors[i + DCTSIZE2 * 0];
+ corr = divisors[i + DCTSIZE2 * 1];
+ shift = divisors[i + DCTSIZE2 * 3];
+
+ if (temp < 0) {
+ temp = -temp;
+ product = (UDCTELEM2)(temp + corr) * recip;
+ product >>= shift + sizeof(DCTELEM) * 8;
+ temp = (DCTELEM)product;
+ temp = -temp;
+ } else {
+ product = (UDCTELEM2)(temp + corr) * recip;
+ product >>= shift + sizeof(DCTELEM) * 8;
+ temp = (DCTELEM)product;
+ }
+ output_ptr[i] = (JCOEF)temp;
+ }
+
+#else
+
+ register DCTELEM qval;
+
+ for (i = 0; i < DCTSIZE2; i++) {
+ qval = divisors[i];
+ temp = workspace[i];
+ /* Divide the coefficient value by qval, ensuring proper rounding.
+ * Since C does not specify the direction of rounding for negative
+ * quotients, we have to force the dividend positive for portability.
+ *
+ * In most files, at least half of the output values will be zero
+ * (at default quantization settings, more like three-quarters...)
+ * so we should ensure that this case is fast. On many machines,
+ * a comparison is enough cheaper than a divide to make a special test
+ * a win. Since both inputs will be nonnegative, we need only test
+ * for a < b to discover whether a/b is 0.
+ * If your machine's division is fast enough, define FAST_DIVIDE.
+ */
+#ifdef FAST_DIVIDE
+#define DIVIDE_BY(a, b) a /= b
+#else
+#define DIVIDE_BY(a, b) if (a >= b) a /= b; else a = 0
+#endif
+ if (temp < 0) {
+ temp = -temp;
+ temp += qval >> 1; /* for rounding */
+ DIVIDE_BY(temp, qval);
+ temp = -temp;
+ } else {
+ temp += qval >> 1; /* for rounding */
+ DIVIDE_BY(temp, qval);
+ }
+ output_ptr[i] = (JCOEF)temp;
+ }
+
+#endif
+
+}
+
+
+/*
+ * Perform forward DCT on one or more blocks of a component.
+ *
+ * The input samples are taken from the sample_data[] array starting at
+ * position start_row/start_col, and moving to the right for any additional
+ * blocks. The quantized coefficients are returned in coef_blocks[].
+ */
+
+METHODDEF(void)
+forward_DCT(j_compress_ptr cinfo, jpeg_component_info *compptr,
+ JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
+ JDIMENSION start_row, JDIMENSION start_col, JDIMENSION num_blocks)
+/* This version is used for integer DCT implementations. */
+{
+ /* This routine is heavily used, so it's worth coding it tightly. */
+ my_fdct_ptr fdct = (my_fdct_ptr)cinfo->fdct;
+ DCTELEM *divisors = fdct->divisors[compptr->quant_tbl_no];
+ DCTELEM *workspace;
+ JDIMENSION bi;
+
+ /* Make sure the compiler doesn't look up these every pass */
+ forward_DCT_method_ptr do_dct = fdct->dct;
+ convsamp_method_ptr do_convsamp = fdct->convsamp;
+ quantize_method_ptr do_quantize = fdct->quantize;
+ workspace = fdct->workspace;
+
+ sample_data += start_row; /* fold in the vertical offset once */
+
+ for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {
+ /* Load data into workspace, applying unsigned->signed conversion */
+ (*do_convsamp) (sample_data, start_col, workspace);
+
+ /* Perform the DCT */
+ (*do_dct) (workspace);
+
+ /* Quantize/descale the coefficients, and store into coef_blocks[] */
+ (*do_quantize) (coef_blocks[bi], divisors, workspace);
+ }
+}
+
+
+#ifdef DCT_FLOAT_SUPPORTED
+
+METHODDEF(void)
+convsamp_float(JSAMPARRAY sample_data, JDIMENSION start_col,
+ FAST_FLOAT *workspace)
+{
+ register FAST_FLOAT *workspaceptr;
+ register JSAMPROW elemptr;
+ register int elemr;
+
+ workspaceptr = workspace;
+ for (elemr = 0; elemr < DCTSIZE; elemr++) {
+ elemptr = sample_data[elemr] + start_col;
+#if DCTSIZE == 8 /* unroll the inner loop */
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+#else
+ {
+ register int elemc;
+ for (elemc = DCTSIZE; elemc > 0; elemc--)
+ *workspaceptr++ = (FAST_FLOAT)((*elemptr++) - CENTERJSAMPLE);
+ }
+#endif
+ }
+}
+
+
+METHODDEF(void)
+quantize_float(JCOEFPTR coef_block, FAST_FLOAT *divisors,
+ FAST_FLOAT *workspace)
+{
+ register FAST_FLOAT temp;
+ register int i;
+ register JCOEFPTR output_ptr = coef_block;
+
+ for (i = 0; i < DCTSIZE2; i++) {
+ /* Apply the quantization and scaling factor */
+ temp = workspace[i] * divisors[i];
+
+ /* Round to nearest integer.
+ * Since C does not specify the direction of rounding for negative
+ * quotients, we have to force the dividend positive for portability.
+ * The maximum coefficient size is +-16K (for 12-bit data), so this
+ * code should work for either 16-bit or 32-bit ints.
+ */
+ output_ptr[i] = (JCOEF)((int)(temp + (FAST_FLOAT)16384.5) - 16384);
+ }
+}
+
+
+METHODDEF(void)
+forward_DCT_float(j_compress_ptr cinfo, jpeg_component_info *compptr,
+ JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
+ JDIMENSION start_row, JDIMENSION start_col,
+ JDIMENSION num_blocks)
+/* This version is used for floating-point DCT implementations. */
+{
+ /* This routine is heavily used, so it's worth coding it tightly. */
+ my_fdct_ptr fdct = (my_fdct_ptr)cinfo->fdct;
+ FAST_FLOAT *divisors = fdct->float_divisors[compptr->quant_tbl_no];
+ FAST_FLOAT *workspace;
+ JDIMENSION bi;
+
+
+ /* Make sure the compiler doesn't look up these every pass */
+ float_DCT_method_ptr do_dct = fdct->float_dct;
+ float_convsamp_method_ptr do_convsamp = fdct->float_convsamp;
+ float_quantize_method_ptr do_quantize = fdct->float_quantize;
+ workspace = fdct->float_workspace;
+
+ sample_data += start_row; /* fold in the vertical offset once */
+
+ for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {
+ /* Load data into workspace, applying unsigned->signed conversion */
+ (*do_convsamp) (sample_data, start_col, workspace);
+
+ /* Perform the DCT */
+ (*do_dct) (workspace);
+
+ /* Quantize/descale the coefficients, and store into coef_blocks[] */
+ (*do_quantize) (coef_blocks[bi], divisors, workspace);
+ }
+}
+
+#endif /* DCT_FLOAT_SUPPORTED */
+
+
+/*
+ * Initialize FDCT manager.
+ */
+
+GLOBAL(void)
+jinit_forward_dct(j_compress_ptr cinfo)
+{
+ my_fdct_ptr fdct;
+ int i;
+
+ fdct = (my_fdct_ptr)
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ sizeof(my_fdct_controller));
+ cinfo->fdct = (struct jpeg_forward_dct *)fdct;
+ fdct->pub.start_pass = start_pass_fdctmgr;
+
+ /* First determine the DCT... */
+ switch (cinfo->dct_method) {
+#ifdef DCT_ISLOW_SUPPORTED
+ case JDCT_ISLOW:
+ fdct->pub.forward_DCT = forward_DCT;
+ if (jsimd_can_fdct_islow())
+ fdct->dct = jsimd_fdct_islow;
+ else
+ fdct->dct = jpeg_fdct_islow;
+ break;
+#endif
+#ifdef DCT_IFAST_SUPPORTED
+ case JDCT_IFAST:
+ fdct->pub.forward_DCT = forward_DCT;
+ if (jsimd_can_fdct_ifast())
+ fdct->dct = jsimd_fdct_ifast;
+ else
+ fdct->dct = jpeg_fdct_ifast;
+ break;
+#endif
+#ifdef DCT_FLOAT_SUPPORTED
+ case JDCT_FLOAT:
+ fdct->pub.forward_DCT = forward_DCT_float;
+ if (jsimd_can_fdct_float())
+ fdct->float_dct = jsimd_fdct_float;
+ else
+ fdct->float_dct = jpeg_fdct_float;
+ break;
+#endif
+ default:
+ ERREXIT(cinfo, JERR_NOT_COMPILED);
+ break;
+ }
+
+ /* ...then the supporting stages. */
+ switch (cinfo->dct_method) {
+#ifdef DCT_ISLOW_SUPPORTED
+ case JDCT_ISLOW:
+#endif
+#ifdef DCT_IFAST_SUPPORTED
+ case JDCT_IFAST:
+#endif
+#if defined(DCT_ISLOW_SUPPORTED) || defined(DCT_IFAST_SUPPORTED)
+ if (jsimd_can_convsamp())
+ fdct->convsamp = jsimd_convsamp;
+ else
+ fdct->convsamp = convsamp;
+ if (jsimd_can_quantize())
+ fdct->quantize = jsimd_quantize;
+ else
+ fdct->quantize = quantize;
+ break;
+#endif
+#ifdef DCT_FLOAT_SUPPORTED
+ case JDCT_FLOAT:
+ if (jsimd_can_convsamp_float())
+ fdct->float_convsamp = jsimd_convsamp_float;
+ else
+ fdct->float_convsamp = convsamp_float;
+ if (jsimd_can_quantize_float())
+ fdct->float_quantize = jsimd_quantize_float;
+ else
+ fdct->float_quantize = quantize_float;
+ break;
+#endif
+ default:
+ ERREXIT(cinfo, JERR_NOT_COMPILED);
+ break;
+ }
+
+ /* Allocate workspace memory */
+#ifdef DCT_FLOAT_SUPPORTED
+ if (cinfo->dct_method == JDCT_FLOAT)
+ fdct->float_workspace = (FAST_FLOAT *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ sizeof(FAST_FLOAT) * DCTSIZE2);
+ else
+#endif
+ fdct->workspace = (DCTELEM *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
+ sizeof(DCTELEM) * DCTSIZE2);
+
+ /* Mark divisor tables unallocated */
+ for (i = 0; i < NUM_QUANT_TBLS; i++) {
+ fdct->divisors[i] = NULL;
+#ifdef DCT_FLOAT_SUPPORTED
+ fdct->float_divisors[i] = NULL;
+#endif
+ }
+}