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7464e5fe76e9f888d7017e49182c0c17b2bc24f5
mozjpeg/jcdctmgr.c
Frank Bossen 7464e5fe76 Fix issue with DC trellis
2014-08-01 16:03:26 -04:00

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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 D. R. Commander
* mozjpeg Modifications:
* Copyright (C) 2014, Mozilla Corporation.
* For conditions of distribution and use, see the accompanying README 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"
#include <assert.h>
#include <math.h>
/* Private subobject for this module */
typedef JMETHOD(void, forward_DCT_method_ptr, (DCTELEM * data));
typedef JMETHOD(void, float_DCT_method_ptr, (FAST_FLOAT * data));
typedef JMETHOD(void, convsamp_method_ptr,
(JSAMPARRAY sample_data, JDIMENSION start_col,
DCTELEM * workspace));
typedef JMETHOD(void, float_convsamp_method_ptr,
(JSAMPARRAY sample_data, JDIMENSION start_col,
FAST_FLOAT *workspace));
typedef JMETHOD(void, quantize_method_ptr,
(JCOEFPTR coef_block, DCTELEM * divisors,
DCTELEM * workspace));
typedef JMETHOD(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;
/*
* 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;
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 */
dtbl[DCTSIZE2 * 2] = (DCTELEM) (1 << (sizeof(DCTELEM)*8*2 - r)); /* scale */
dtbl[DCTSIZE2 * 3] = (DCTELEM) r - sizeof(DCTELEM)*8; /* shift */
if(r <= 16) return 0;
else return 1;
}
/*
* 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(!compute_reciprocal(qtbl->quantval[i] << 3, &dtbl[i])
&& fdct->quantize == jsimd_quantize)
fdct->quantize = quantize;
}
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(!compute_reciprocal(
DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[i],
(INT32) aanscales[i]),
CONST_BITS-3), &dtbl[i])
&& fdct->quantize == jsimd_quantize)
fdct->quantize = quantize;
}
}
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++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
#else
{
register int elemc;
for (elemc = DCTSIZE; elemc > 0; elemc--)
*workspaceptr++ = GETJSAMPLE(*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;
UDCTELEM recip, corr, shift;
UDCTELEM2 product;
JCOEFPTR output_ptr = coef_block;
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 = product;
temp = -temp;
} else {
product = (UDCTELEM2)(temp + corr) * recip;
product >>= shift + sizeof(DCTELEM)*8;
temp = product;
}
output_ptr[i] = (JCOEF) temp;
}
}
/*
* 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, JBLOCKROW dst)
/* 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);
/* Save unquantized transform coefficients for later trellis quantization */
if (dst) {
int i;
if (cinfo->dct_method == JDCT_IFAST) {
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
};
for (i = 0; i < DCTSIZE2; i++) {
int x = workspace[i];
int s = aanscales[i];
x = (x >= 0) ? (x * 32768 + s) / (2*s) : (x * 32768 - s) / (2*s);
dst[bi][i] = x;
}
} else {
for (i = 0; i < DCTSIZE2; i++) {
dst[bi][i] = workspace[i];
}
}
}
/* 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)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
#else
{
register int elemc;
for (elemc = DCTSIZE; elemc > 0; elemc--)
*workspaceptr++ = (FAST_FLOAT)
(GETJSAMPLE(*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, JBLOCKROW dst)
/* 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;
float v;
int x;
/* 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);
/* Save unquantized transform coefficients for later trellis quantization */
/* Currently save as integer values. Could save float values but would require */
/* modifications to memory allocation and trellis quantization */
if (dst) {
int i;
static const double aanscalefactor[DCTSIZE] = {
1.0, 1.387039845, 1.306562965, 1.175875602,
1.0, 0.785694958, 0.541196100, 0.275899379
};
for (i = 0; i < DCTSIZE2; i++) {
v = workspace[i];
v /= aanscalefactor[i%8];
v /= aanscalefactor[i/8];
x = (v >= 0.0) ? (int)(v + 0.5) : (int)(v - 0.5);
dst[bi][i] = x;
}
}
/* Quantize/descale the coefficients, and store into coef_blocks[] */
(*do_quantize) (coef_blocks[bi], divisors, workspace);
}
}
#endif /* DCT_FLOAT_SUPPORTED */
#include "jchuff.h"
#include "jpeg_nbits_table.h"
static const float jpeg_lambda_weights_flat[64] = {
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f
};
static const float jpeg_lambda_weights_csf_luma[64] = {
3.35630f, 3.59892f, 3.20921f, 2.28102f, 1.42378f, 0.88079f, 0.58190f, 0.43454f,
3.59893f, 3.21284f, 2.71282f, 1.98092f, 1.30506f, 0.83852f, 0.56346f, 0.42146f,
3.20921f, 2.71282f, 2.12574f, 1.48616f, 0.99660f, 0.66132f, 0.45610f, 0.34609f,
2.28102f, 1.98092f, 1.48616f, 0.97492f, 0.64622f, 0.43812f, 0.31074f, 0.24072f,
1.42378f, 1.30506f, 0.99660f, 0.64623f, 0.42051f, 0.28446f, 0.20380f, 0.15975f,
0.88079f, 0.83852f, 0.66132f, 0.43812f, 0.28446f, 0.19092f, 0.13635f, 0.10701f,
0.58190f, 0.56346f, 0.45610f, 0.31074f, 0.20380f, 0.13635f, 0.09674f, 0.07558f,
0.43454f, 0.42146f, 0.34609f, 0.24072f, 0.15975f, 0.10701f, 0.07558f, 0.05875f,
};
GLOBAL(void)
quantize_trellis(j_compress_ptr cinfo, c_derived_tbl *dctbl, c_derived_tbl *actbl, JBLOCKROW coef_blocks, JBLOCKROW src, JDIMENSION num_blocks,
JQUANT_TBL * qtbl, double *norm_src, double *norm_coef, JCOEF *last_dc_val)
{
int i, j, k, l;
float accumulated_zero_dist[DCTSIZE2];
float accumulated_cost[DCTSIZE2];
int run_start[DCTSIZE2];
int bi;
float best_cost;
int last_coeff_idx; /* position of last nonzero coefficient */
float norm = 0.0;
float lambda_base;
float lambda;
float lambda_dc;
const float *lambda_tbl = (cinfo->use_lambda_weight_tbl) ? jpeg_lambda_weights_csf_luma : jpeg_lambda_weights_flat;
int Ss, Se;
float *accumulated_zero_block_cost = NULL;
float *accumulated_block_cost = NULL;
int *block_run_start = NULL;
int *requires_eob = NULL;
int has_eob;
float cost_all_zeros;
float best_cost_skip;
float cost;
int zero_run;
int run_bits;
int rate;
float *accumulated_dc_cost[3];
int *dc_cost_backtrack[3];
JCOEF *dc_candidate[3];
Ss = cinfo->Ss;
Se = cinfo->Se;
if (Ss == 0)
Ss = 1;
if (Se < Ss)
return;
if (cinfo->trellis_eob_opt) {
accumulated_zero_block_cost = (float *)malloc((num_blocks + 1) * SIZEOF(float));
accumulated_block_cost = (float *)malloc((num_blocks + 1) * SIZEOF(float));
block_run_start = (int *)malloc(num_blocks * SIZEOF(int));
requires_eob = (int *)malloc((num_blocks + 1) * SIZEOF(int));
accumulated_zero_block_cost[0] = 0;
accumulated_block_cost[0] = 0;
requires_eob[0] = 0;
}
if (cinfo->trellis_quant_dc) {
for (i = 0; i < 3; i++) {
accumulated_dc_cost[i] = (float *)malloc(num_blocks * SIZEOF(float));
dc_cost_backtrack[i] = (int *)malloc(num_blocks * SIZEOF(int));
dc_candidate[i] = (JCOEF *)malloc(num_blocks * SIZEOF(JCOEF));
}
}
norm = 0.0;
for (i = 1; i < DCTSIZE2; i++) {
norm += qtbl->quantval[i] * qtbl->quantval[i];
}
norm /= 63.0;
lambda_base = 1.0 / norm;
for (bi = 0; bi < num_blocks; bi++) {
norm = 0.0;
for (i = 1; i < DCTSIZE2; i++) {
norm += src[bi][i] * src[bi][i];
}
norm /= 63.0;
if (cinfo->lambda_log_scale2 > 0.0)
lambda = pow(2.0, cinfo->lambda_log_scale1) * lambda_base / (pow(2.0, cinfo->lambda_log_scale2) + norm);
else
lambda = pow(2.0, cinfo->lambda_log_scale1-12.0) * lambda_base;
lambda_dc = lambda * lambda_tbl[0];
accumulated_zero_dist[Ss-1] = 0.0;
accumulated_cost[Ss-1] = 0.0;
// Do DC coefficient
if (cinfo->trellis_quant_dc) {
int sign = src[bi][0] >> 31;
int x = abs(src[bi][0]);
int q = 8 * qtbl->quantval[0];
int qval;
float dc_candidate_dist;
qval = (x + q/2) / q; /* quantized value (round nearest) */
for (k = 0; k < 3; k++) {
int delta;
int dc_delta;
int bits;
dc_candidate[k][bi] = qval - 1 + k;
delta = dc_candidate[k][bi] * q - x;
dc_candidate_dist = delta * delta * lambda_dc;
dc_candidate[k][bi] *= 1 + 2*sign;
if (bi == 0) {
dc_delta = dc_candidate[k][bi] - *last_dc_val;
// Derive number of suffix bits
bits = 0;
dc_delta = abs(dc_delta);
while (dc_delta) {
dc_delta >>= 1;
bits++;
}
cost = bits + dctbl->ehufsi[bits] + dc_candidate_dist;
accumulated_dc_cost[k][0] = cost;
dc_cost_backtrack[k][0] = -1;
} else {
for (l = 0; l < 3; l++) {
dc_delta = dc_candidate[k][bi] - dc_candidate[l][bi-1];
// Derive number of suffix bits
bits = 0;
dc_delta = abs(dc_delta);
while (dc_delta) {
dc_delta >>= 1;
bits++;
}
cost = bits + dctbl->ehufsi[bits] + dc_candidate_dist + accumulated_dc_cost[l][bi-1];
if (l == 0 || cost < accumulated_dc_cost[k][bi]) {
accumulated_dc_cost[k][bi] = cost;
dc_cost_backtrack[k][bi] = l;
}
}
}
}
}
// Do AC coefficients
for (i = Ss; i <= Se; i++) {
int z = jpeg_natural_order[i];
int sign = src[bi][z] >> 31;
int x = abs(src[bi][z]);
int q = 8 * qtbl->quantval[z];
int candidate[16];
int candidate_bits[16];
float candidate_dist[16];
int num_candidates;
int qval;
accumulated_zero_dist[i] = x * x * lambda * lambda_tbl[z] + accumulated_zero_dist[i-1];
qval = (x + q/2) / q; /* quantized value (round nearest) */
if (qval == 0) {
coef_blocks[bi][z] = 0;
accumulated_cost[i] = 1e38; /* Shouldn't be needed */
continue;
}
num_candidates = jpeg_nbits_table[qval];
for (k = 0; k < num_candidates; k++) {
int delta;
candidate[k] = (k < num_candidates - 1) ? (2 << k) - 1 : qval;
delta = candidate[k] * q - x;
candidate_bits[k] = k+1;
candidate_dist[k] = delta * delta * lambda * lambda_tbl[z];
}
accumulated_cost[i] = 1e38;
for (j = Ss-1; j < i; j++) {
int zz = jpeg_natural_order[j];
if (j != Ss-1 && coef_blocks[bi][zz] == 0)
continue;
zero_run = i - 1 - j;
if ((zero_run >> 4) && actbl->ehufsi[0xf0] == 0)
continue;
run_bits = (zero_run >> 4) * actbl->ehufsi[0xf0];
zero_run &= 15;
for (k = 0; k < num_candidates; k++) {
int coef_bits = actbl->ehufsi[16 * zero_run + candidate_bits[k]];
if (coef_bits == 0)
continue;
rate = coef_bits + candidate_bits[k] + run_bits;
cost = rate + candidate_dist[k];
cost += accumulated_zero_dist[i-1] - accumulated_zero_dist[j] + accumulated_cost[j];
if (cost < accumulated_cost[i]) {
coef_blocks[bi][z] = (candidate[k] ^ sign) - sign;
accumulated_cost[i] = cost;
run_start[i] = j;
}
}
}
}
last_coeff_idx = Ss-1;
best_cost = accumulated_zero_dist[Se] + actbl->ehufsi[0];
cost_all_zeros = accumulated_zero_dist[Se];
best_cost_skip = cost_all_zeros;
for (i = Ss; i <= Se; i++) {
int z = jpeg_natural_order[i];
if (coef_blocks[bi][z] != 0) {
float cost = accumulated_cost[i] + accumulated_zero_dist[Se] - accumulated_zero_dist[i];
float cost_wo_eob = cost;
if (i < Se)
cost += actbl->ehufsi[0];
if (cost < best_cost) {
best_cost = cost;
last_coeff_idx = i;
best_cost_skip = cost_wo_eob;
}
}
}
has_eob = (last_coeff_idx < Se) + (last_coeff_idx == Ss-1);
/* Zero out coefficients that are part of runs */
i = Se;
while (i >= Ss)
{
while (i > last_coeff_idx) {
int z = jpeg_natural_order[i];
coef_blocks[bi][z] = 0;
i--;
}
last_coeff_idx = run_start[i];
i--;
}
if (cinfo->trellis_eob_opt) {
accumulated_zero_block_cost[bi+1] = accumulated_zero_block_cost[bi];
accumulated_zero_block_cost[bi+1] += cost_all_zeros;
requires_eob[bi+1] = has_eob;
best_cost = 1e38;
if (has_eob != 2) {
for (i = 0; i <= bi; i++) {
int zero_block_run;
int nbits;
float cost;
if (requires_eob[i] == 2)
continue;
cost = best_cost_skip; /* cost of coding a nonzero block */
cost += accumulated_zero_block_cost[bi];
cost -= accumulated_zero_block_cost[i];
cost += accumulated_block_cost[i];
zero_block_run = bi - i + requires_eob[i];
nbits = jpeg_nbits_table[zero_block_run];
cost += actbl->ehufsi[16*nbits] + nbits;
if (cost < best_cost) {
block_run_start[bi] = i;
best_cost = cost;
accumulated_block_cost[bi+1] = cost;
}
}
}
}
}
if (cinfo->trellis_eob_opt) {
int last_block = num_blocks;
best_cost = 1e38;
for (i = 0; i <= num_blocks; i++) {
int zero_block_run;
int nbits;
float cost = 0.0;
if (requires_eob[i] == 2)
continue;
cost += accumulated_zero_block_cost[num_blocks];
cost -= accumulated_zero_block_cost[i];
zero_block_run = num_blocks - i + requires_eob[i];
nbits = jpeg_nbits_table[zero_block_run];
cost += actbl->ehufsi[16*nbits] + nbits;
if (cost < best_cost) {
best_cost = cost;
last_block = i;
}
}
last_block--;
bi = num_blocks - 1;
while (bi >= 0) {
while (bi > last_block) {
for (j = Ss; j <= Se; j++) {
int z = jpeg_natural_order[j];
coef_blocks[bi][z] = 0;
}
bi--;
}
last_block = block_run_start[bi]-1;
bi--;
}
free(accumulated_zero_block_cost);
free(accumulated_block_cost);
free(block_run_start);
free(requires_eob);
}
if (cinfo->trellis_q_opt) {
for (bi = 0; bi < num_blocks; bi++) {
for (i = 1; i < DCTSIZE2; i++) {
norm_src[i] += src[bi][i] * coef_blocks[bi][i];
norm_coef[i] += 8 * coef_blocks[bi][i] * coef_blocks[bi][i];
}
}
}
if (cinfo->trellis_quant_dc) {
j = 0;
for (i = 1; i < 3; i++) {
if (accumulated_dc_cost[i][num_blocks-1] < accumulated_dc_cost[j][num_blocks-1])
j = i;
}
for (bi = num_blocks-1; bi >= 0; bi--) {
coef_blocks[bi][0] = dc_candidate[j][bi];
j = dc_cost_backtrack[j][bi];
}
// Save DC predictor
*last_dc_val = coef_blocks[num_blocks-1][0];
for (i = 0; i < 3; i++) {
free(accumulated_dc_cost[i]);
free(dc_cost_backtrack[i]);
free(dc_candidate[i]);
}
}
}
/*
* 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
}
}
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