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/*
* jcmaster.c
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2003-2010 by Guido Vollbeding.
* Lossless JPEG Modifications:
* Copyright (C) 1999, Ken Murchison.
* libjpeg-turbo Modifications:
* Copyright (C) 2010, 2016, 2018, 2022-2024, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
* This file contains master control logic for the JPEG compressor.
* These routines are concerned with parameter validation, initial setup,
* and inter-pass control (determining the number of passes and the work
* to be done in each pass).
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jpegapicomp.h"
#include "jcmaster.h"
/*
* Support routines that do various essential calculations.
*/
#if JPEG_LIB_VERSION >= 70
/*
* Compute JPEG image dimensions and related values.
* NOTE: this is exported for possible use by application.
* Hence it mustn't do anything that can't be done twice.
*/
GLOBAL(void)
jpeg_calc_jpeg_dimensions(j_compress_ptr cinfo)
/* Do computations that are needed before master selection phase */
{
int data_unit = cinfo->master->lossless ? 1 : DCTSIZE;
/* Hardwire it to "no scaling" */
cinfo->jpeg_width = cinfo->image_width;
cinfo->jpeg_height = cinfo->image_height;
cinfo->min_DCT_h_scaled_size = data_unit;
cinfo->min_DCT_v_scaled_size = data_unit;
}
#endif
LOCAL(boolean)
using_std_huff_tables(j_compress_ptr cinfo)
{
int i;
static const UINT8 bits_dc_luminance[17] = {
/* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0
};
static const UINT8 val_dc_luminance[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
};
static const UINT8 bits_dc_chrominance[17] = {
/* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0
};
static const UINT8 val_dc_chrominance[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
};
static const UINT8 bits_ac_luminance[17] = {
/* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d
};
static const UINT8 val_ac_luminance[] = {
0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa
};
static const UINT8 bits_ac_chrominance[17] = {
/* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77
};
static const UINT8 val_ac_chrominance[] = {
0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa
};
if (cinfo->dc_huff_tbl_ptrs[0] == NULL ||
cinfo->ac_huff_tbl_ptrs[0] == NULL ||
cinfo->dc_huff_tbl_ptrs[1] == NULL ||
cinfo->ac_huff_tbl_ptrs[1] == NULL)
return FALSE;
for (i = 2; i < NUM_HUFF_TBLS; i++) {
if (cinfo->dc_huff_tbl_ptrs[i] != NULL ||
cinfo->ac_huff_tbl_ptrs[i] != NULL)
return FALSE;
}
if (memcmp(cinfo->dc_huff_tbl_ptrs[0]->bits, bits_dc_luminance,
sizeof(bits_dc_luminance)) ||
memcmp(cinfo->dc_huff_tbl_ptrs[0]->huffval, val_dc_luminance,
sizeof(val_dc_luminance)) ||
memcmp(cinfo->ac_huff_tbl_ptrs[0]->bits, bits_ac_luminance,
sizeof(bits_ac_luminance)) ||
memcmp(cinfo->ac_huff_tbl_ptrs[0]->huffval, val_ac_luminance,
sizeof(val_ac_luminance)) ||
memcmp(cinfo->dc_huff_tbl_ptrs[1]->bits, bits_dc_chrominance,
sizeof(bits_dc_chrominance)) ||
memcmp(cinfo->dc_huff_tbl_ptrs[1]->huffval, val_dc_chrominance,
sizeof(val_dc_chrominance)) ||
memcmp(cinfo->ac_huff_tbl_ptrs[1]->bits, bits_ac_chrominance,
sizeof(bits_ac_chrominance)) ||
memcmp(cinfo->ac_huff_tbl_ptrs[1]->huffval, val_ac_chrominance,
sizeof(val_ac_chrominance)))
return FALSE;
return TRUE;
}
LOCAL(void)
initial_setup(j_compress_ptr cinfo, boolean transcode_only)
/* Do computations that are needed before master selection phase */
{
int ci;
jpeg_component_info *compptr;
long samplesperrow;
JDIMENSION jd_samplesperrow;
int data_unit = cinfo->master->lossless ? 1 : DCTSIZE;
#if JPEG_LIB_VERSION >= 70
#if JPEG_LIB_VERSION >= 80
if (!transcode_only)
#endif
jpeg_calc_jpeg_dimensions(cinfo);
#endif
/* Sanity check on image dimensions */
if (cinfo->_jpeg_height <= 0 || cinfo->_jpeg_width <= 0 ||
cinfo->num_components <= 0 || cinfo->input_components <= 0)
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
/* Make sure image isn't bigger than I can handle */
if ((long)cinfo->_jpeg_height > (long)JPEG_MAX_DIMENSION ||
(long)cinfo->_jpeg_width > (long)JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int)JPEG_MAX_DIMENSION);
/* Width of an input scanline must be representable as JDIMENSION. */
samplesperrow = (long)cinfo->image_width * (long)cinfo->input_components;
jd_samplesperrow = (JDIMENSION)samplesperrow;
if ((long)jd_samplesperrow != samplesperrow)
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
#ifdef C_LOSSLESS_SUPPORTED
if (cinfo->data_precision != 8 && cinfo->data_precision != 12 &&
cinfo->data_precision != 16)
#else
if (cinfo->data_precision != 8 && cinfo->data_precision != 12)
#endif
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
/* Check that number of components won't exceed internal array sizes */
if (cinfo->num_components > MAX_COMPONENTS)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPONENTS);
/* Compute maximum sampling factors; check factor validity */
cinfo->max_h_samp_factor = 1;
cinfo->max_v_samp_factor = 1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->h_samp_factor <= 0 ||
compptr->h_samp_factor > MAX_SAMP_FACTOR ||
compptr->v_samp_factor <= 0 ||
compptr->v_samp_factor > MAX_SAMP_FACTOR)
ERREXIT(cinfo, JERR_BAD_SAMPLING);
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
compptr->h_samp_factor);
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
compptr->v_samp_factor);
}
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Fill in the correct component_index value; don't rely on application */
compptr->component_index = ci;
/* For compression, we never do DCT scaling. */
#if JPEG_LIB_VERSION >= 70
compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size = data_unit;
#else
compptr->DCT_scaled_size = data_unit;
#endif
/* Size in data units */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long)cinfo->_jpeg_width * (long)compptr->h_samp_factor,
(long)(cinfo->max_h_samp_factor * data_unit));
compptr->height_in_blocks = (JDIMENSION)
jdiv_round_up((long)cinfo->_jpeg_height * (long)compptr->v_samp_factor,
(long)(cinfo->max_v_samp_factor * data_unit));
/* Size in samples */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long)cinfo->_jpeg_width * (long)compptr->h_samp_factor,
(long)cinfo->max_h_samp_factor);
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long)cinfo->_jpeg_height * (long)compptr->v_samp_factor,
(long)cinfo->max_v_samp_factor);
/* Mark component needed (this flag isn't actually used for compression) */
compptr->component_needed = TRUE;
}
/* Compute number of fully interleaved MCU rows (number of times that
* main controller will call coefficient or difference controller).
*/
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long)cinfo->_jpeg_height,
(long)(cinfo->max_v_samp_factor * data_unit));
}
#if defined(C_MULTISCAN_FILES_SUPPORTED) || defined(C_LOSSLESS_SUPPORTED)
#define NEED_SCAN_SCRIPT
#endif
#ifdef NEED_SCAN_SCRIPT
LOCAL(void)
validate_script(j_compress_ptr cinfo)
/* Verify that the scan script in cinfo->scan_info[] is valid; also
* determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
*/
{
const jpeg_scan_info *scanptr;
int scanno, ncomps, ci, coefi, thisi;
int Ss, Se, Ah, Al;
boolean component_sent[MAX_COMPONENTS];
#ifdef C_PROGRESSIVE_SUPPORTED
int *last_bitpos_ptr;
int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
/* -1 until that coefficient has been seen; then last Al for it */
#endif
if (cinfo->num_scans <= 0)
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
#ifndef C_MULTISCAN_FILES_SUPPORTED
if (cinfo->num_scans > 1)
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
scanptr = cinfo->scan_info;
if (scanptr->Ss != 0 && scanptr->Se == 0) {
#ifdef C_LOSSLESS_SUPPORTED
cinfo->master->lossless = TRUE;
cinfo->progressive_mode = FALSE;
for (ci = 0; ci < cinfo->num_components; ci++)
component_sent[ci] = FALSE;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
}
/* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
* for progressive JPEG, no scan can have this.
*/
else if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2 - 1) {
#ifdef C_PROGRESSIVE_SUPPORTED
cinfo->progressive_mode = TRUE;
cinfo->master->lossless = FALSE;
last_bitpos_ptr = &last_bitpos[0][0];
for (ci = 0; ci < cinfo->num_components; ci++)
for (coefi = 0; coefi < DCTSIZE2; coefi++)
*last_bitpos_ptr++ = -1;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
cinfo->progressive_mode = cinfo->master->lossless = FALSE;
for (ci = 0; ci < cinfo->num_components; ci++)
component_sent[ci] = FALSE;
}
for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
/* Validate component indexes */
ncomps = scanptr->comps_in_scan;
if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
for (ci = 0; ci < ncomps; ci++) {
thisi = scanptr->component_index[ci];
if (thisi < 0 || thisi >= cinfo->num_components)
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
/* Components must appear in SOF order within each scan */
if (ci > 0 && thisi <= scanptr->component_index[ci - 1])
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
}
/* Validate progression parameters */
Ss = scanptr->Ss;
Se = scanptr->Se;
Ah = scanptr->Ah;
Al = scanptr->Al;
if (cinfo->progressive_mode) {
#ifdef C_PROGRESSIVE_SUPPORTED
/* Rec. ITU-T T.81 | ISO/IEC 10918-1 simply gives the ranges 0..13 for Ah
* and Al, but that seems wrong: the upper bound ought to depend on data
* precision. Perhaps they really meant 0..N+1 for N-bit precision.
* Here we allow 0..10 for 8-bit data; Al larger than 10 results in
* out-of-range reconstructed DC values during the first DC scan,
* which might cause problems for some decoders.
*/
int max_Ah_Al = cinfo->data_precision == 12 ? 13 : 10;
if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
Ah < 0 || Ah > max_Ah_Al || Al < 0 || Al > max_Ah_Al)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
if (Ss == 0) {
if (Se != 0) /* DC and AC together not OK */
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
} else {
if (ncomps != 1) /* AC scans must be for only one component */
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
}
for (ci = 0; ci < ncomps; ci++) {
last_bitpos_ptr = &last_bitpos[scanptr->component_index[ci]][0];
if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
for (coefi = Ss; coefi <= Se; coefi++) {
if (last_bitpos_ptr[coefi] < 0) {
/* first scan of this coefficient */
if (Ah != 0)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
} else {
/* not first scan */
if (Ah != last_bitpos_ptr[coefi] || Al != Ah - 1)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
}
last_bitpos_ptr[coefi] = Al;
}
}
#endif
} else {
#ifdef C_LOSSLESS_SUPPORTED
if (cinfo->master->lossless) {
/* The JPEG spec simply gives the range 0..15 for Al (Pt), but that
* seems wrong: the upper bound ought to depend on data precision.
* Perhaps they really meant 0..N-1 for N-bit precision, which is what
* we allow here. Values greater than or equal to the data precision
* will result in a blank image.
*/
if (Ss < 1 || Ss > 7 || /* predictor selection value */
Se != 0 || Ah != 0 ||
Al < 0 || Al >= cinfo->data_precision) /* point transform */
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
} else
#endif
{
/* For sequential JPEG, all progression parameters must be these: */
if (Ss != 0 || Se != DCTSIZE2 - 1 || Ah != 0 || Al != 0)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
}
/* Make sure components are not sent twice */
for (ci = 0; ci < ncomps; ci++) {
thisi = scanptr->component_index[ci];
if (component_sent[thisi])
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
component_sent[thisi] = TRUE;
}
}
}
/* Now verify that everything got sent. */
if (cinfo->progressive_mode) {
#ifdef C_PROGRESSIVE_SUPPORTED
/* For progressive mode, we only check that at least some DC data
* got sent for each component; the spec does not require that all bits
* of all coefficients be transmitted. Would it be wiser to enforce
* transmission of all coefficient bits??
*/
for (ci = 0; ci < cinfo->num_components; ci++) {
if (last_bitpos[ci][0] < 0)
ERREXIT(cinfo, JERR_MISSING_DATA);
}
#endif
} else {
for (ci = 0; ci < cinfo->num_components; ci++) {
if (!component_sent[ci])
ERREXIT(cinfo, JERR_MISSING_DATA);
}
}
}
#endif /* NEED_SCAN_SCRIPT */
LOCAL(void)
select_scan_parameters(j_compress_ptr cinfo)
/* Set up the scan parameters for the current scan */
{
int ci;
#ifdef NEED_SCAN_SCRIPT
if (cinfo->scan_info != NULL) {
/* Prepare for current scan --- the script is already validated */
my_master_ptr master = (my_master_ptr)cinfo->master;
const jpeg_scan_info *scanptr = cinfo->scan_info + master->scan_number;
cinfo->comps_in_scan = scanptr->comps_in_scan;
for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
cinfo->cur_comp_info[ci] =
&cinfo->comp_info[scanptr->component_index[ci]];
}
cinfo->Ss = scanptr->Ss;
cinfo->Se = scanptr->Se;
cinfo->Ah = scanptr->Ah;
cinfo->Al = scanptr->Al;
} else
#endif
{
/* Prepare for single sequential-JPEG scan containing all components */
if (cinfo->num_components > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPS_IN_SCAN);
cinfo->comps_in_scan = cinfo->num_components;
for (ci = 0; ci < cinfo->num_components; ci++) {
cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
}
if (!cinfo->master->lossless) {
cinfo->Ss = 0;
cinfo->Se = DCTSIZE2 - 1;
cinfo->Ah = 0;
cinfo->Al = 0;
}
}
}
LOCAL(void)
per_scan_setup(j_compress_ptr cinfo)
/* Do computations that are needed before processing a JPEG scan */
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
{
int ci, mcublks, tmp;
jpeg_component_info *compptr;
int data_unit = cinfo->master->lossless ? 1 : DCTSIZE;
if (cinfo->comps_in_scan == 1) {
/* Noninterleaved (single-component) scan */
compptr = cinfo->cur_comp_info[0];
/* Overall image size in MCUs */
cinfo->MCUs_per_row = compptr->width_in_blocks;
cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
/* For noninterleaved scan, always one block per MCU */
compptr->MCU_width = 1;
compptr->MCU_height = 1;
compptr->MCU_blocks = 1;
compptr->MCU_sample_width = data_unit;
compptr->last_col_width = 1;
/* For noninterleaved scans, it is convenient to define last_row_height
* as the number of block rows present in the last iMCU row.
*/
tmp = (int)(compptr->height_in_blocks % compptr->v_samp_factor);
if (tmp == 0) tmp = compptr->v_samp_factor;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
cinfo->blocks_in_MCU = 1;
cinfo->MCU_membership[0] = 0;
} else {
/* Interleaved (multi-component) scan */
if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
MAX_COMPS_IN_SCAN);
/* Overall image size in MCUs */
cinfo->MCUs_per_row = (JDIMENSION)
jdiv_round_up((long)cinfo->_jpeg_width,
(long)(cinfo->max_h_samp_factor * data_unit));
cinfo->MCU_rows_in_scan = (JDIMENSION)
jdiv_round_up((long)cinfo->_jpeg_height,
(long)(cinfo->max_v_samp_factor * data_unit));
cinfo->blocks_in_MCU = 0;
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Sampling factors give # of blocks of component in each MCU */
compptr->MCU_width = compptr->h_samp_factor;
compptr->MCU_height = compptr->v_samp_factor;
compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
compptr->MCU_sample_width = compptr->MCU_width * data_unit;
/* Figure number of non-dummy blocks in last MCU column & row */
tmp = (int)(compptr->width_in_blocks % compptr->MCU_width);
if (tmp == 0) tmp = compptr->MCU_width;
compptr->last_col_width = tmp;
tmp = (int)(compptr->height_in_blocks % compptr->MCU_height);
if (tmp == 0) tmp = compptr->MCU_height;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
mcublks = compptr->MCU_blocks;
if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
while (mcublks-- > 0) {
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
}
}
}
/* Convert restart specified in rows to actual MCU count. */
/* Note that count must fit in 16 bits, so we provide limiting. */
if (cinfo->restart_in_rows > 0) {
long nominal = (long)cinfo->restart_in_rows * (long)cinfo->MCUs_per_row;
cinfo->restart_interval = (unsigned int)MIN(nominal, 65535L);
}
}
/*
* Per-pass setup.
* This is called at the beginning of each pass. We determine which modules
* will be active during this pass and give them appropriate start_pass calls.
* We also set is_last_pass to indicate whether any more passes will be
* required.
*/
METHODDEF(void)
prepare_for_pass(j_compress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr)cinfo->master;
switch (master->pass_type) {
case main_pass:
/* Initial pass: will collect input data, and do either Huffman
* optimization or data output for the first scan.
*/
select_scan_parameters(cinfo);
per_scan_setup(cinfo);
if (!cinfo->raw_data_in) {
(*cinfo->cconvert->start_pass) (cinfo);
(*cinfo->downsample->start_pass) (cinfo);
(*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
}
(*cinfo->fdct->start_pass) (cinfo);
(*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
(*cinfo->coef->start_pass) (cinfo,
(master->total_passes > 1 ?
JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
(*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
if (cinfo->optimize_coding) {
/* No immediate data output; postpone writing frame/scan headers */
master->pub.call_pass_startup = FALSE;
} else {
/* Will write frame/scan headers at first jpeg_write_scanlines call */
master->pub.call_pass_startup = TRUE;
}
break;
#ifdef ENTROPY_OPT_SUPPORTED
case huff_opt_pass:
/* Do Huffman optimization for a scan after the first one. */
select_scan_parameters(cinfo);
per_scan_setup(cinfo);
if (cinfo->Ss != 0 || cinfo->Ah == 0 || cinfo->arith_code ||
cinfo->master->lossless) {
(*cinfo->entropy->start_pass) (cinfo, TRUE);
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
master->pub.call_pass_startup = FALSE;
break;
}
/* Special case: Huffman DC refinement scans need no Huffman table
* and therefore we can skip the optimization pass for them.
*/
master->pass_type = output_pass;
master->pass_number++;
#endif
FALLTHROUGH /*FALLTHROUGH*/
case output_pass:
/* Do a data-output pass. */
/* We need not repeat per-scan setup if prior optimization pass did it. */
if (!cinfo->optimize_coding) {
select_scan_parameters(cinfo);
per_scan_setup(cinfo);
}
(*cinfo->entropy->start_pass) (cinfo, FALSE);
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
/* We emit frame/scan headers now */
if (master->scan_number == 0)
(*cinfo->marker->write_frame_header) (cinfo);
(*cinfo->marker->write_scan_header) (cinfo);
master->pub.call_pass_startup = FALSE;
break;
default:
ERREXIT(cinfo, JERR_NOT_COMPILED);
}
master->pub.is_last_pass = (master->pass_number == master->total_passes - 1);
/* Set up progress monitor's pass info if present */
if (cinfo->progress != NULL) {
cinfo->progress->completed_passes = master->pass_number;
cinfo->progress->total_passes = master->total_passes;
}
}
/*
* Special start-of-pass hook.
* This is called by jpeg_write_scanlines if call_pass_startup is TRUE.
* In single-pass processing, we need this hook because we don't want to
* write frame/scan headers during jpeg_start_compress; we want to let the
* application write COM markers etc. between jpeg_start_compress and the
* jpeg_write_scanlines loop.
* In multi-pass processing, this routine is not used.
*/
METHODDEF(void)
pass_startup(j_compress_ptr cinfo)
{
cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
(*cinfo->marker->write_frame_header) (cinfo);
(*cinfo->marker->write_scan_header) (cinfo);
}
/*
* Finish up at end of pass.
*/
METHODDEF(void)
finish_pass_master(j_compress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr)cinfo->master;
/* The entropy coder always needs an end-of-pass call,
* either to analyze statistics or to flush its output buffer.
*/
(*cinfo->entropy->finish_pass) (cinfo);
/* Update state for next pass */
switch (master->pass_type) {
case main_pass:
/* next pass is either output of scan 0 (after optimization)
* or output of scan 1 (if no optimization).
*/
master->pass_type = output_pass;
if (!cinfo->optimize_coding)
master->scan_number++;
break;
case huff_opt_pass:
/* next pass is always output of current scan */
master->pass_type = output_pass;
break;
case output_pass:
/* next pass is either optimization or output of next scan */
if (cinfo->optimize_coding)
master->pass_type = huff_opt_pass;
master->scan_number++;
break;
}
master->pass_number++;
}
/*
* Initialize master compression control.
*/
GLOBAL(void)
jinit_c_master_control(j_compress_ptr cinfo, boolean transcode_only)
{
my_master_ptr master = (my_master_ptr)cinfo->master;
boolean empty_huff_tables = TRUE;
int i;
master->pub.prepare_for_pass = prepare_for_pass;
master->pub.pass_startup = pass_startup;
master->pub.finish_pass = finish_pass_master;
master->pub.is_last_pass = FALSE;
if (cinfo->scan_info != NULL) {
#ifdef NEED_SCAN_SCRIPT
validate_script(cinfo);
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
cinfo->progressive_mode = FALSE;
cinfo->num_scans = 1;
}
/* Disable smoothing and subsampling in lossless mode, since those are lossy
* algorithms. Set the JPEG colorspace to the input colorspace. Disable raw
* (downsampled) data input, because it isn't particularly useful without
* subsampling and has not been tested in lossless mode.
*/
if (cinfo->master->lossless) {
int ci;
jpeg_component_info *compptr;
cinfo->raw_data_in = FALSE;
cinfo->smoothing_factor = 0;
jpeg_default_colorspace(cinfo);
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++)
compptr->h_samp_factor = compptr->v_samp_factor = 1;
}
/* Validate parameters, determine derived values */
initial_setup(cinfo, transcode_only);
if (cinfo->arith_code)
cinfo->optimize_coding = FALSE;
else {
if (cinfo->master->lossless || /* TEMPORARY HACK ??? */
cinfo->progressive_mode)
cinfo->optimize_coding = TRUE; /* assume default tables no good for
progressive mode or lossless mode */
for (i = 0; i < NUM_HUFF_TBLS; i++) {
if (cinfo->dc_huff_tbl_ptrs[i] != NULL ||
cinfo->ac_huff_tbl_ptrs[i] != NULL) {
empty_huff_tables = FALSE;
break;
}
}
if (cinfo->data_precision == 12 && !cinfo->optimize_coding &&
(empty_huff_tables || using_std_huff_tables(cinfo)))
cinfo->optimize_coding = TRUE; /* assume default tables no good for
12-bit data precision */
}
/* Initialize my private state */
if (transcode_only) {
/* no main pass in transcoding */
if (cinfo->optimize_coding)
master->pass_type = huff_opt_pass;
else
master->pass_type = output_pass;
} else {
/* for normal compression, first pass is always this type: */
master->pass_type = main_pass;
}
master->scan_number = 0;
master->pass_number = 0;
if (cinfo->optimize_coding)
master->total_passes = cinfo->num_scans * 2;
else
master->total_passes = cinfo->num_scans;
master->jpeg_version = PACKAGE_NAME " version " VERSION " (build " BUILD ")";
}