/*+ −
* jdmaster.c+ −
*+ −
* Copyright (C) 1991-1997, Thomas G. Lane.+ −
* 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 master control logic for the JPEG decompressor.+ −
* These routines are concerned with selecting the modules to be executed+ −
* and with determining the number of passes and the work to be done in each+ −
* pass.+ −
*/+ −
+ − #define JPEG_INTERNALS+ −
#include "jinclude.h"+ −
#include "jpeglib.h"+ −
+ − + − /* Private state */+ −
+ − typedef struct {+ −
struct jpeg_decomp_master pub; /* public fields */+ −
+ − int pass_number; /* # of passes completed */+ −
+ − boolean using_merged_upsample; /* TRUE if using merged upsample/cconvert */+ −
+ − /* Saved references to initialized quantizer modules,+ −
* in case we need to switch modes.+ −
*/+ −
struct jpeg_color_quantizer * quantizer_1pass;+ −
struct jpeg_color_quantizer * quantizer_2pass;+ −
} my_decomp_master;+ −
+ − typedef my_decomp_master * my_master_ptr;+ −
+ − + − /*+ −
* Determine whether merged upsample/color conversion should be used.+ −
* CRUCIAL: this must match the actual capabilities of jdmerge.c!+ −
*/+ −
+ − LOCAL(boolean)+ −
use_merged_upsample (j_decompress_ptr cinfo)+ −
{+ −
#ifdef UPSAMPLE_MERGING_SUPPORTED+ −
/* Merging is the equivalent of plain box-filter upsampling */+ −
if (cinfo->do_fancy_upsampling || cinfo->CCIR601_sampling)+ −
return FALSE;+ −
/* jdmerge.c only supports YCC=>RGB color conversion */+ −
if (cinfo->jpeg_color_space != JCS_YCbCr || cinfo->num_components != 3 ||+ −
cinfo->out_color_space != JCS_RGB ||+ −
cinfo->out_color_components != RGB_PIXELSIZE)+ −
return FALSE;+ −
/* and it only handles 2h1v or 2h2v sampling ratios */+ −
if (cinfo->comp_info[0].h_samp_factor != 2 ||+ −
cinfo->comp_info[1].h_samp_factor != 1 ||+ −
cinfo->comp_info[2].h_samp_factor != 1 ||+ −
cinfo->comp_info[0].v_samp_factor > 2 ||+ −
cinfo->comp_info[1].v_samp_factor != 1 ||+ −
cinfo->comp_info[2].v_samp_factor != 1)+ −
return FALSE;+ −
/* furthermore, it doesn't work if we've scaled the IDCTs differently */+ −
if (cinfo->comp_info[0].DCT_scaled_size != cinfo->min_DCT_scaled_size ||+ −
cinfo->comp_info[1].DCT_scaled_size != cinfo->min_DCT_scaled_size ||+ −
cinfo->comp_info[2].DCT_scaled_size != cinfo->min_DCT_scaled_size)+ −
return FALSE;+ −
/* ??? also need to test for upsample-time rescaling, when & if supported */+ −
return TRUE; /* by golly, it'll work... */+ −
#else+ −
return FALSE;+ −
#endif+ −
}+ −
+ − + − /*+ −
* Compute output 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.+ −
* Also note that it may be called before the master module is initialized!+ −
*/+ −
+ − GLOBAL(void)+ −
jpeg_calc_output_dimensions (j_decompress_ptr cinfo)+ −
/* Do computations that are needed before master selection phase */+ −
{+ −
#ifdef IDCT_SCALING_SUPPORTED+ −
int ci;+ −
jpeg_component_info *compptr;+ −
#endif+ −
+ − /* Prevent application from calling me at wrong times */+ −
if (cinfo->global_state != DSTATE_READY)+ −
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);+ −
+ − #ifdef IDCT_SCALING_SUPPORTED+ −
+ − /* Compute actual output image dimensions and DCT scaling choices. */+ −
if (cinfo->scale_num * 8 <= cinfo->scale_denom) {+ −
/* Provide 1/8 scaling */+ −
cinfo->output_width = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_width, 8L);+ −
cinfo->output_height = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_height, 8L);+ −
cinfo->min_DCT_scaled_size = 1;+ −
} else if (cinfo->scale_num * 4 <= cinfo->scale_denom) {+ −
/* Provide 1/4 scaling */+ −
cinfo->output_width = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_width, 4L);+ −
cinfo->output_height = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_height, 4L);+ −
cinfo->min_DCT_scaled_size = 2;+ −
} else if (cinfo->scale_num * 2 <= cinfo->scale_denom) {+ −
/* Provide 1/2 scaling */+ −
cinfo->output_width = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_width, 2L);+ −
cinfo->output_height = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_height, 2L);+ −
cinfo->min_DCT_scaled_size = 4;+ −
} else {+ −
/* Provide 1/1 scaling */+ −
cinfo->output_width = cinfo->image_width;+ −
cinfo->output_height = cinfo->image_height;+ −
cinfo->min_DCT_scaled_size = DCTSIZE;+ −
}+ −
/* In selecting the actual DCT scaling for each component, we try to+ −
* scale up the chroma components via IDCT scaling rather than upsampling.+ −
* This saves time if the upsampler gets to use 1:1 scaling.+ −
* Note this code assumes that the supported DCT scalings are powers of 2.+ −
*/+ −
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;+ −
ci++, compptr++) {+ −
int ssize = cinfo->min_DCT_scaled_size;+ −
while (ssize < DCTSIZE &&+ −
(compptr->h_samp_factor * ssize * 2 <=+ −
cinfo->max_h_samp_factor * cinfo->min_DCT_scaled_size) &&+ −
(compptr->v_samp_factor * ssize * 2 <=+ −
cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size)) {+ −
ssize = ssize * 2;+ −
}+ −
compptr->DCT_scaled_size = ssize;+ −
}+ −
+ − /* Recompute downsampled dimensions of components;+ −
* application needs to know these if using raw downsampled data.+ −
*/+ −
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;+ −
ci++, compptr++) {+ −
/* Size in samples, after IDCT scaling */+ −
compptr->downsampled_width = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_width *+ −
(long) (compptr->h_samp_factor * compptr->DCT_scaled_size),+ −
(long) (cinfo->max_h_samp_factor * DCTSIZE));+ −
compptr->downsampled_height = (JDIMENSION)+ −
jdiv_round_up((long) cinfo->image_height *+ −
(long) (compptr->v_samp_factor * compptr->DCT_scaled_size),+ −
(long) (cinfo->max_v_samp_factor * DCTSIZE));+ −
}+ −
+ − #else /* !IDCT_SCALING_SUPPORTED */+ −
+ − /* Hardwire it to "no scaling" */+ −
cinfo->output_width = cinfo->image_width;+ −
cinfo->output_height = cinfo->image_height;+ −
/* jdinput.c has already initialized DCT_scaled_size to DCTSIZE,+ −
* and has computed unscaled downsampled_width and downsampled_height.+ −
*/+ −
+ − #endif /* IDCT_SCALING_SUPPORTED */+ −
+ − /* Report number of components in selected colorspace. */+ −
/* Probably this should be in the color conversion module... */+ −
switch (cinfo->out_color_space) {+ −
case JCS_GRAYSCALE:+ −
cinfo->out_color_components = 1;+ −
break;+ −
case JCS_RGB:+ −
#if RGB_PIXELSIZE != 3+ −
cinfo->out_color_components = RGB_PIXELSIZE;+ −
break;+ −
#endif /* else share code with YCbCr */+ −
case JCS_YCbCr:+ −
cinfo->out_color_components = 3;+ −
break;+ −
case JCS_CMYK:+ −
case JCS_YCCK:+ −
cinfo->out_color_components = 4;+ −
break;+ −
default: /* else must be same colorspace as in file */+ −
cinfo->out_color_components = cinfo->num_components;+ −
break;+ −
}+ −
cinfo->output_components = (cinfo->quantize_colors ? 1 :+ −
cinfo->out_color_components);+ −
+ − /* See if upsampler will want to emit more than one row at a time */+ −
if (use_merged_upsample(cinfo))+ −
cinfo->rec_outbuf_height = cinfo->max_v_samp_factor;+ −
else+ −
cinfo->rec_outbuf_height = 1;+ −
}+ −
+ − + − /*+ −
* Several decompression processes need to range-limit values to the range+ −
* 0..MAXJSAMPLE; the input value may fall somewhat outside this range+ −
* due to noise introduced by quantization, roundoff error, etc. These+ −
* processes are inner loops and need to be as fast as possible. On most+ −
* machines, particularly CPUs with pipelines or instruction prefetch,+ −
* a (subscript-check-less) C table lookup+ −
* x = sample_range_limit[x];+ −
* is faster than explicit tests+ −
* if (x < 0) x = 0;+ −
* else if (x > MAXJSAMPLE) x = MAXJSAMPLE;+ −
* These processes all use a common table prepared by the routine below.+ −
*+ −
* For most steps we can mathematically guarantee that the initial value+ −
* of x is within MAXJSAMPLE+1 of the legal range, so a table running from+ −
* -(MAXJSAMPLE+1) to 2*MAXJSAMPLE+1 is sufficient. But for the initial+ −
* limiting step (just after the IDCT), a wildly out-of-range value is + −
* possible if the input data is corrupt. To avoid any chance of indexing+ −
* off the end of memory and getting a bad-pointer trap, we perform the+ −
* post-IDCT limiting thus:+ −
* x = range_limit[x & MASK];+ −
* where MASK is 2 bits wider than legal sample data, ie 10 bits for 8-bit+ −
* samples. Under normal circumstances this is more than enough range and+ −
* a correct output will be generated; with bogus input data the mask will+ −
* cause wraparound, and we will safely generate a bogus-but-in-range output.+ −
* For the post-IDCT step, we want to convert the data from signed to unsigned+ −
* representation by adding CENTERJSAMPLE at the same time that we limit it.+ −
* So the post-IDCT limiting table ends up looking like this:+ −
* CENTERJSAMPLE,CENTERJSAMPLE+1,...,MAXJSAMPLE,+ −
* MAXJSAMPLE (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times),+ −
* 0 (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times),+ −
* 0,1,...,CENTERJSAMPLE-1+ −
* Negative inputs select values from the upper half of the table after+ −
* masking.+ −
*+ −
* We can save some space by overlapping the start of the post-IDCT table+ −
* with the simpler range limiting table. The post-IDCT table begins at+ −
* sample_range_limit + CENTERJSAMPLE.+ −
*+ −
* Note that the table is allocated in near data space on PCs; it's small+ −
* enough and used often enough to justify this.+ −
*/+ −
+ − LOCAL(void)+ −
prepare_range_limit_table (j_decompress_ptr cinfo)+ −
/* Allocate and fill in the sample_range_limit table */+ −
{+ −
JSAMPLE * table;+ −
int i;+ −
+ − table = (JSAMPLE *)+ −
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,+ −
(5 * (MAXJSAMPLE+1) + CENTERJSAMPLE) * SIZEOF(JSAMPLE));+ −
table += (MAXJSAMPLE+1); /* allow negative subscripts of simple table */+ −
cinfo->sample_range_limit = table;+ −
/* First segment of "simple" table: limit[x] = 0 for x < 0 */+ −
MEMZERO(table - (MAXJSAMPLE+1), (MAXJSAMPLE+1) * SIZEOF(JSAMPLE));+ −
/* Main part of "simple" table: limit[x] = x */+ −
for (i = 0; i <= MAXJSAMPLE; i++)+ −
table[i] = (JSAMPLE) i;+ −
table += CENTERJSAMPLE; /* Point to where post-IDCT table starts */+ −
/* End of simple table, rest of first half of post-IDCT table */+ −
for (i = CENTERJSAMPLE; i < 2*(MAXJSAMPLE+1); i++)+ −
table[i] = MAXJSAMPLE;+ −
/* Second half of post-IDCT table */+ −
MEMZERO(table + (2 * (MAXJSAMPLE+1)),+ −
(2 * (MAXJSAMPLE+1) - CENTERJSAMPLE) * SIZEOF(JSAMPLE));+ −
MEMCOPY(table + (4 * (MAXJSAMPLE+1) - CENTERJSAMPLE),+ −
cinfo->sample_range_limit, CENTERJSAMPLE * SIZEOF(JSAMPLE));+ −
}+ −
+ − + − /*+ −
* Master selection of decompression modules.+ −
* This is done once at jpeg_start_decompress time. We determine+ −
* which modules will be used and give them appropriate initialization calls.+ −
* We also initialize the decompressor input side to begin consuming data.+ −
*+ −
* Since jpeg_read_header has finished, we know what is in the SOF+ −
* and (first) SOS markers. We also have all the application parameter+ −
* settings.+ −
*/+ −
+ − LOCAL(void)+ −
master_selection (j_decompress_ptr cinfo)+ −
{+ −
my_master_ptr master = (my_master_ptr) cinfo->master;+ −
boolean use_c_buffer;+ −
long samplesperrow;+ −
JDIMENSION jd_samplesperrow;+ −
+ − /* Initialize dimensions and other stuff */+ −
jpeg_calc_output_dimensions(cinfo);+ −
prepare_range_limit_table(cinfo);+ −
+ − /* Width of an output scanline must be representable as JDIMENSION. */+ −
samplesperrow = (long) cinfo->output_width * (long) cinfo->out_color_components;+ −
jd_samplesperrow = (JDIMENSION) samplesperrow;+ −
if ((long) jd_samplesperrow != samplesperrow)+ −
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);+ −
+ − /* Initialize my private state */+ −
master->pass_number = 0;+ −
master->using_merged_upsample = use_merged_upsample(cinfo);+ −
+ − /* Color quantizer selection */+ −
master->quantizer_1pass = NULL;+ −
master->quantizer_2pass = NULL;+ −
/* No mode changes if not using buffered-image mode. */+ −
if (! cinfo->quantize_colors || ! cinfo->buffered_image) {+ −
cinfo->enable_1pass_quant = FALSE;+ −
cinfo->enable_external_quant = FALSE;+ −
cinfo->enable_2pass_quant = FALSE;+ −
}+ −
if (cinfo->quantize_colors) {+ −
if (cinfo->raw_data_out)+ −
ERREXIT(cinfo, JERR_NOTIMPL);+ −
/* 2-pass quantizer only works in 3-component color space. */+ −
if (cinfo->out_color_components != 3) {+ −
cinfo->enable_1pass_quant = TRUE;+ −
cinfo->enable_external_quant = FALSE;+ −
cinfo->enable_2pass_quant = FALSE;+ −
cinfo->colormap = NULL;+ −
} else if (cinfo->colormap != NULL) {+ −
cinfo->enable_external_quant = TRUE;+ −
} else if (cinfo->two_pass_quantize) {+ −
cinfo->enable_2pass_quant = TRUE;+ −
} else {+ −
cinfo->enable_1pass_quant = TRUE;+ −
}+ −
+ − if (cinfo->enable_1pass_quant) {+ −
#ifdef QUANT_1PASS_SUPPORTED+ −
jinit_1pass_quantizer(cinfo);+ −
master->quantizer_1pass = cinfo->cquantize;+ −
#else+ −
ERREXIT(cinfo, JERR_NOT_COMPILED);+ −
#endif+ −
}+ −
+ − /* We use the 2-pass code to map to external colormaps. */+ −
if (cinfo->enable_2pass_quant || cinfo->enable_external_quant) {+ −
#ifdef QUANT_2PASS_SUPPORTED+ −
jinit_2pass_quantizer(cinfo);+ −
master->quantizer_2pass = cinfo->cquantize;+ −
#else+ −
ERREXIT(cinfo, JERR_NOT_COMPILED);+ −
#endif+ −
}+ −
/* If both quantizers are initialized, the 2-pass one is left active;+ −
* this is necessary for starting with quantization to an external map.+ −
*/+ −
}+ −
+ − /* Post-processing: in particular, color conversion first */+ −
if (! cinfo->raw_data_out) {+ −
if (master->using_merged_upsample) {+ −
#ifdef UPSAMPLE_MERGING_SUPPORTED+ −
jinit_merged_upsampler(cinfo); /* does color conversion too */+ −
#else+ −
ERREXIT(cinfo, JERR_NOT_COMPILED);+ −
#endif+ −
} else {+ −
jinit_color_deconverter(cinfo);+ −
jinit_upsampler(cinfo);+ −
}+ −
jinit_d_post_controller(cinfo, cinfo->enable_2pass_quant);+ −
}+ −
/* Inverse DCT */+ −
jinit_inverse_dct(cinfo);+ −
/* Entropy decoding: either Huffman or arithmetic coding. */+ −
if (cinfo->arith_code) {+ −
ERREXIT(cinfo, JERR_ARITH_NOTIMPL);+ −
} else {+ −
if (cinfo->progressive_mode) {+ −
#ifdef D_PROGRESSIVE_SUPPORTED+ −
jinit_phuff_decoder(cinfo);+ −
#else+ −
ERREXIT(cinfo, JERR_NOT_COMPILED);+ −
#endif+ −
} else+ −
jinit_huff_decoder(cinfo);+ −
}+ −
+ − /* Initialize principal buffer controllers. */+ −
use_c_buffer = cinfo->inputctl->has_multiple_scans || cinfo->buffered_image;+ −
jinit_d_coef_controller(cinfo, use_c_buffer);+ −
+ − if (! cinfo->raw_data_out)+ −
jinit_d_main_controller(cinfo, FALSE /* never need full buffer here */);+ −
+ − /* We can now tell the memory manager to allocate virtual arrays. */+ −
(*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);+ −
+ − /* Initialize input side of decompressor to consume first scan. */+ −
(*cinfo->inputctl->start_input_pass) (cinfo);+ −
+ − #ifdef D_MULTISCAN_FILES_SUPPORTED+ −
/* If jpeg_start_decompress will read the whole file, initialize+ −
* progress monitoring appropriately. The input step is counted+ −
* as one pass.+ −
*/+ −
if (cinfo->progress != NULL && ! cinfo->buffered_image &&+ −
cinfo->inputctl->has_multiple_scans) {+ −
int nscans;+ −
/* Estimate number of scans to set pass_limit. */+ −
if (cinfo->progressive_mode) {+ −
/* Arbitrarily estimate 2 interleaved DC scans + 3 AC scans/component. */+ −
nscans = 2 + 3 * cinfo->num_components;+ −
} else {+ −
/* For a nonprogressive multiscan file, estimate 1 scan per component. */+ −
nscans = cinfo->num_components;+ −
}+ −
cinfo->progress->pass_counter = 0L;+ −
cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows * nscans;+ −
cinfo->progress->completed_passes = 0;+ −
cinfo->progress->total_passes = (cinfo->enable_2pass_quant ? 3 : 2);+ −
/* Count the input pass as done */+ −
master->pass_number++;+ −
}+ −
#endif /* D_MULTISCAN_FILES_SUPPORTED */+ −
}+ −
+ − + − /*+ −
* Per-pass setup.+ −
* This is called at the beginning of each output pass. We determine which+ −
* modules will be active during this pass and give them appropriate+ −
* start_pass calls. We also set is_dummy_pass to indicate whether this+ −
* is a "real" output pass or a dummy pass for color quantization.+ −
* (In the latter case, jdapistd.c will crank the pass to completion.)+ −
*/+ −
+ − METHODDEF(void)+ −
prepare_for_output_pass (j_decompress_ptr cinfo)+ −
{+ −
my_master_ptr master = (my_master_ptr) cinfo->master;+ −
+ − if (master->pub.is_dummy_pass) {+ −
#ifdef QUANT_2PASS_SUPPORTED+ −
/* Final pass of 2-pass quantization */+ −
master->pub.is_dummy_pass = FALSE;+ −
(*cinfo->cquantize->start_pass) (cinfo, FALSE);+ −
(*cinfo->post->start_pass) (cinfo, JBUF_CRANK_DEST);+ −
(*cinfo->main->start_pass) (cinfo, JBUF_CRANK_DEST);+ −
#else+ −
ERREXIT(cinfo, JERR_NOT_COMPILED);+ −
#endif /* QUANT_2PASS_SUPPORTED */+ −
} else {+ −
if (cinfo->quantize_colors && cinfo->colormap == NULL) {+ −
/* Select new quantization method */+ −
if (cinfo->two_pass_quantize && cinfo->enable_2pass_quant) {+ −
cinfo->cquantize = master->quantizer_2pass;+ −
master->pub.is_dummy_pass = TRUE;+ −
} else if (cinfo->enable_1pass_quant) {+ −
cinfo->cquantize = master->quantizer_1pass;+ −
} else {+ −
ERREXIT(cinfo, JERR_MODE_CHANGE);+ −
}+ −
}+ −
(*cinfo->idct->start_pass) (cinfo);+ −
(*cinfo->coef->start_output_pass) (cinfo);+ −
if (! cinfo->raw_data_out) {+ −
if (! master->using_merged_upsample)+ −
(*cinfo->cconvert->start_pass) (cinfo);+ −
(*cinfo->upsample->start_pass) (cinfo);+ −
if (cinfo->quantize_colors)+ −
(*cinfo->cquantize->start_pass) (cinfo, master->pub.is_dummy_pass);+ −
(*cinfo->post->start_pass) (cinfo,+ −
(master->pub.is_dummy_pass ? JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));+ −
(*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);+ −
}+ −
}+ −
+ − /* 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->pass_number ++ −
(master->pub.is_dummy_pass ? 2 : 1);+ −
/* In buffered-image mode, we assume one more output pass if EOI not+ −
* yet reached, but no more passes if EOI has been reached.+ −
*/+ −
if (cinfo->buffered_image && ! cinfo->inputctl->eoi_reached) {+ −
cinfo->progress->total_passes += (cinfo->enable_2pass_quant ? 2 : 1);+ −
}+ −
}+ −
}+ −
+ − + − /*+ −
* Finish up at end of an output pass.+ −
*/+ −
+ − METHODDEF(void)+ −
finish_output_pass (j_decompress_ptr cinfo)+ −
{+ −
my_master_ptr master = (my_master_ptr) cinfo->master;+ −
+ − if (cinfo->quantize_colors)+ −
(*cinfo->cquantize->finish_pass) (cinfo);+ −
master->pass_number++;+ −
}+ −
+ − + − #ifdef D_MULTISCAN_FILES_SUPPORTED+ −
+ − /*+ −
* Switch to a new external colormap between output passes.+ −
*/+ −
+ − GLOBAL(void)+ −
jpeg_new_colormap (j_decompress_ptr cinfo)+ −
{+ −
my_master_ptr master = (my_master_ptr) cinfo->master;+ −
+ − /* Prevent application from calling me at wrong times */+ −
if (cinfo->global_state != DSTATE_BUFIMAGE)+ −
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);+ −
+ − if (cinfo->quantize_colors && cinfo->enable_external_quant &&+ −
cinfo->colormap != NULL) {+ −
/* Select 2-pass quantizer for external colormap use */+ −
cinfo->cquantize = master->quantizer_2pass;+ −
/* Notify quantizer of colormap change */+ −
(*cinfo->cquantize->new_color_map) (cinfo);+ −
master->pub.is_dummy_pass = FALSE; /* just in case */+ −
} else+ −
ERREXIT(cinfo, JERR_MODE_CHANGE);+ −
}+ −
+ − #endif /* D_MULTISCAN_FILES_SUPPORTED */+ −
+ − + − /*+ −
* Initialize master decompression control and select active modules.+ −
* This is performed at the start of jpeg_start_decompress.+ −
*/+ −
+ − GLOBAL(void)+ −
jinit_master_decompress (j_decompress_ptr cinfo)+ −
{+ −
my_master_ptr master;+ −
+ − master = (my_master_ptr)+ −
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,+ −
SIZEOF(my_decomp_master));+ −
cinfo->master = (struct jpeg_decomp_master *) master;+ −
master->pub.prepare_for_output_pass = prepare_for_output_pass;+ −
master->pub.finish_output_pass = finish_output_pass;+ −
+ − master->pub.is_dummy_pass = FALSE;+ −
+ − master_selection(cinfo);+ −
}+ −