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raze/libraries/jpeg/jdinput.c
Christoph Oelckers 718112a8fe - added external libraries for music format playback and decompression from GZDoom. 
Currently none of these is being used, but eventually they will, once more code gets ported over.
So it's better to have them right away and avoid editing the project file too much, only to revert that later.
2019-09-22 08:59:48 +02:00

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/*
* jdinput.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2002-2013 by Guido Vollbeding.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains input control logic for the JPEG decompressor.
* These routines are concerned with controlling the decompressor's input
* processing (marker reading and coefficient decoding). The actual input
* reading is done in jdmarker.c, jdhuff.c, and jdarith.c.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Private state */
typedef struct {
struct jpeg_input_controller pub; /* public fields */
int inheaders; /* Nonzero until first SOS is reached */
} my_input_controller;
typedef my_input_controller * my_inputctl_ptr;
/* Forward declarations */
METHODDEF(int) consume_markers JPP((j_decompress_ptr cinfo));
/*
* Routines to calculate various quantities related to the size of the image.
*/
/*
* 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.
*/
GLOBAL(void)
jpeg_core_output_dimensions (j_decompress_ptr cinfo)
/* Do computations that are needed before master selection phase.
* This function is used for transcoding and full decompression.
*/
{
#ifdef IDCT_SCALING_SUPPORTED
int ci;
jpeg_component_info *compptr;
/* Compute actual output image dimensions and DCT scaling choices. */
if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom) {
/* Provide 1/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 1;
cinfo->min_DCT_v_scaled_size = 1;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 2) {
/* Provide 2/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 2L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 2L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 2;
cinfo->min_DCT_v_scaled_size = 2;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 3) {
/* Provide 3/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 3L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 3L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 3;
cinfo->min_DCT_v_scaled_size = 3;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 4) {
/* Provide 4/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 4L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 4L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 4;
cinfo->min_DCT_v_scaled_size = 4;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 5) {
/* Provide 5/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 5L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 5L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 5;
cinfo->min_DCT_v_scaled_size = 5;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 6) {
/* Provide 6/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 6L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 6L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 6;
cinfo->min_DCT_v_scaled_size = 6;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 7) {
/* Provide 7/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 7L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 7L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 7;
cinfo->min_DCT_v_scaled_size = 7;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 8) {
/* Provide 8/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 8L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 8L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 8;
cinfo->min_DCT_v_scaled_size = 8;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 9) {
/* Provide 9/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 9L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 9L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 9;
cinfo->min_DCT_v_scaled_size = 9;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 10) {
/* Provide 10/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 10L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 10L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 10;
cinfo->min_DCT_v_scaled_size = 10;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 11) {
/* Provide 11/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 11L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 11L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 11;
cinfo->min_DCT_v_scaled_size = 11;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 12) {
/* Provide 12/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 12L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 12L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 12;
cinfo->min_DCT_v_scaled_size = 12;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 13) {
/* Provide 13/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 13L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 13L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 13;
cinfo->min_DCT_v_scaled_size = 13;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 14) {
/* Provide 14/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 14L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 14L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 14;
cinfo->min_DCT_v_scaled_size = 14;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 15) {
/* Provide 15/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 15L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 15L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 15;
cinfo->min_DCT_v_scaled_size = 15;
} else {
/* Provide 16/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 16L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 16L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 16;
cinfo->min_DCT_v_scaled_size = 16;
}
/* Recompute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size;
compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size;
}
#else /* !IDCT_SCALING_SUPPORTED */
/* Hardwire it to "no scaling" */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
/* initial_setup has already initialized DCT_scaled_size,
* and has computed unscaled downsampled_width and downsampled_height.
*/
#endif /* IDCT_SCALING_SUPPORTED */
}
LOCAL(void)
initial_setup (j_decompress_ptr cinfo)
/* Called once, when first SOS marker is reached */
{
int ci;
jpeg_component_info *compptr;
/* Make sure image isn't bigger than I can handle */
if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||
(long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
/* Only 8 to 12 bits data precision are supported for DCT based JPEG */
if (cinfo->data_precision < 8 || cinfo->data_precision > 12)
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);
}
/* Derive block_size, natural_order, and lim_Se */
if (cinfo->is_baseline || (cinfo->progressive_mode &&
cinfo->comps_in_scan)) { /* no pseudo SOS marker */
cinfo->block_size = DCTSIZE;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
} else
switch (cinfo->Se) {
case (1*1-1):
cinfo->block_size = 1;
cinfo->natural_order = jpeg_natural_order; /* not needed */
cinfo->lim_Se = cinfo->Se;
break;
case (2*2-1):
cinfo->block_size = 2;
cinfo->natural_order = jpeg_natural_order2;
cinfo->lim_Se = cinfo->Se;
break;
case (3*3-1):
cinfo->block_size = 3;
cinfo->natural_order = jpeg_natural_order3;
cinfo->lim_Se = cinfo->Se;
break;
case (4*4-1):
cinfo->block_size = 4;
cinfo->natural_order = jpeg_natural_order4;
cinfo->lim_Se = cinfo->Se;
break;
case (5*5-1):
cinfo->block_size = 5;
cinfo->natural_order = jpeg_natural_order5;
cinfo->lim_Se = cinfo->Se;
break;
case (6*6-1):
cinfo->block_size = 6;
cinfo->natural_order = jpeg_natural_order6;
cinfo->lim_Se = cinfo->Se;
break;
case (7*7-1):
cinfo->block_size = 7;
cinfo->natural_order = jpeg_natural_order7;
cinfo->lim_Se = cinfo->Se;
break;
case (8*8-1):
cinfo->block_size = 8;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (9*9-1):
cinfo->block_size = 9;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (10*10-1):
cinfo->block_size = 10;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (11*11-1):
cinfo->block_size = 11;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (12*12-1):
cinfo->block_size = 12;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (13*13-1):
cinfo->block_size = 13;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (14*14-1):
cinfo->block_size = 14;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (15*15-1):
cinfo->block_size = 15;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (16*16-1):
cinfo->block_size = 16;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
default:
ERREXIT4(cinfo, JERR_BAD_PROGRESSION,
cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);
break;
}
/* We initialize DCT_scaled_size and min_DCT_scaled_size to block_size.
* In the full decompressor,
* this will be overridden by jpeg_calc_output_dimensions in jdmaster.c;
* but in the transcoder,
* jpeg_calc_output_dimensions is not used, so we must do it here.
*/
cinfo->min_DCT_h_scaled_size = cinfo->block_size;
cinfo->min_DCT_v_scaled_size = cinfo->block_size;
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_h_scaled_size = cinfo->block_size;
compptr->DCT_v_scaled_size = cinfo->block_size;
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
compptr->height_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
/* downsampled_width and downsampled_height will also be overridden by
* jdmaster.c if we are doing full decompression. The transcoder library
* doesn't use these values, but the calling application might.
*/
/* Size in samples */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) cinfo->max_h_samp_factor);
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) cinfo->max_v_samp_factor);
/* Mark component needed, until color conversion says otherwise */
compptr->component_needed = TRUE;
/* Mark no quantization table yet saved for component */
compptr->quant_table = NULL;
}
/* Compute number of fully interleaved MCU rows. */
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
/* Decide whether file contains multiple scans */
if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode)
cinfo->inputctl->has_multiple_scans = TRUE;
else
cinfo->inputctl->has_multiple_scans = FALSE;
}
LOCAL(void)
per_scan_setup (j_decompress_ptr cinfo)
/* Do computations that are needed before processing a JPEG scan */
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */
{
int ci, mcublks, tmp;
jpeg_component_info *compptr;
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 = compptr->DCT_h_scaled_size;
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->image_width,
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
cinfo->MCU_rows_in_scan = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
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 * compptr->DCT_h_scaled_size;
/* 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 > D_MAX_BLOCKS_IN_MCU)
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
while (mcublks-- > 0) {
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
}
}
}
}
/*
* Save away a copy of the Q-table referenced by each component present
* in the current scan, unless already saved during a prior scan.
*
* In a multiple-scan JPEG file, the encoder could assign different components
* the same Q-table slot number, but change table definitions between scans
* so that each component uses a different Q-table. (The IJG encoder is not
* currently capable of doing this, but other encoders might.) Since we want
* to be able to dequantize all the components at the end of the file, this
* means that we have to save away the table actually used for each component.
* We do this by copying the table at the start of the first scan containing
* the component.
* The JPEG spec prohibits the encoder from changing the contents of a Q-table
* slot between scans of a component using that slot. If the encoder does so
* anyway, this decoder will simply use the Q-table values that were current
* at the start of the first scan for the component.
*
* The decompressor output side looks only at the saved quant tables,
* not at the current Q-table slots.
*/
LOCAL(void)
latch_quant_tables (j_decompress_ptr cinfo)
{
int ci, qtblno;
jpeg_component_info *compptr;
JQUANT_TBL * qtbl;
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* No work if we already saved Q-table for this component */
if (compptr->quant_table != NULL)
continue;
/* Make sure specified quantization table is present */
qtblno = compptr->quant_tbl_no;
if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||
cinfo->quant_tbl_ptrs[qtblno] == NULL)
ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);
/* OK, save away the quantization table */
qtbl = (JQUANT_TBL *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(JQUANT_TBL));
MEMCOPY(qtbl, cinfo->quant_tbl_ptrs[qtblno], SIZEOF(JQUANT_TBL));
compptr->quant_table = qtbl;
}
}
/*
* Initialize the input modules to read a scan of compressed data.
* The first call to this is done by jdmaster.c after initializing
* the entire decompressor (during jpeg_start_decompress).
* Subsequent calls come from consume_markers, below.
*/
METHODDEF(void)
start_input_pass (j_decompress_ptr cinfo)
{
per_scan_setup(cinfo);
latch_quant_tables(cinfo);
(*cinfo->entropy->start_pass) (cinfo);
(*cinfo->coef->start_input_pass) (cinfo);
cinfo->inputctl->consume_input = cinfo->coef->consume_data;
}
/*
* Finish up after inputting a compressed-data scan.
* This is called by the coefficient controller after it's read all
* the expected data of the scan.
*/
METHODDEF(void)
finish_input_pass (j_decompress_ptr cinfo)
{
(*cinfo->entropy->finish_pass) (cinfo);
cinfo->inputctl->consume_input = consume_markers;
}
/*
* Read JPEG markers before, between, or after compressed-data scans.
* Change state as necessary when a new scan is reached.
* Return value is JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
*
* The consume_input method pointer points either here or to the
* coefficient controller's consume_data routine, depending on whether
* we are reading a compressed data segment or inter-segment markers.
*
* Note: This function should NOT return a pseudo SOS marker (with zero
* component number) to the caller. A pseudo marker received by
* read_markers is processed and then skipped for other markers.
*/
METHODDEF(int)
consume_markers (j_decompress_ptr cinfo)
{
my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl;
int val;
if (inputctl->pub.eoi_reached) /* After hitting EOI, read no further */
return JPEG_REACHED_EOI;
for (;;) { /* Loop to pass pseudo SOS marker */
val = (*cinfo->marker->read_markers) (cinfo);
switch (val) {
case JPEG_REACHED_SOS: /* Found SOS */
if (inputctl->inheaders) { /* 1st SOS */
if (inputctl->inheaders == 1)
initial_setup(cinfo);
if (cinfo->comps_in_scan == 0) { /* pseudo SOS marker */
inputctl->inheaders = 2;
break;
}
inputctl->inheaders = 0;
/* Note: start_input_pass must be called by jdmaster.c
* before any more input can be consumed. jdapimin.c is
* responsible for enforcing this sequencing.
*/
} else { /* 2nd or later SOS marker */
if (! inputctl->pub.has_multiple_scans)
ERREXIT(cinfo, JERR_EOI_EXPECTED); /* Oops, I wasn't expecting this! */
if (cinfo->comps_in_scan == 0) /* unexpected pseudo SOS marker */
break;
start_input_pass(cinfo);
}
return val;
case JPEG_REACHED_EOI: /* Found EOI */
inputctl->pub.eoi_reached = TRUE;
if (inputctl->inheaders) { /* Tables-only datastream, apparently */
if (cinfo->marker->saw_SOF)
ERREXIT(cinfo, JERR_SOF_NO_SOS);
} else {
/* Prevent infinite loop in coef ctlr's decompress_data routine
* if user set output_scan_number larger than number of scans.
*/
if (cinfo->output_scan_number > cinfo->input_scan_number)
cinfo->output_scan_number = cinfo->input_scan_number;
}
return val;
case JPEG_SUSPENDED:
return val;
default:
return val;
}
}
}
/*
* Reset state to begin a fresh datastream.
*/
METHODDEF(void)
reset_input_controller (j_decompress_ptr cinfo)
{
my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl;
inputctl->pub.consume_input = consume_markers;
inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */
inputctl->pub.eoi_reached = FALSE;
inputctl->inheaders = 1;
/* Reset other modules */
(*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
(*cinfo->marker->reset_marker_reader) (cinfo);
/* Reset progression state -- would be cleaner if entropy decoder did this */
cinfo->coef_bits = NULL;
}
/*
* Initialize the input controller module.
* This is called only once, when the decompression object is created.
*/
GLOBAL(void)
jinit_input_controller (j_decompress_ptr cinfo)
{
my_inputctl_ptr inputctl;
/* Create subobject in permanent pool */
inputctl = (my_inputctl_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
SIZEOF(my_input_controller));
cinfo->inputctl = &inputctl->pub;
/* Initialize method pointers */
inputctl->pub.consume_input = consume_markers;
inputctl->pub.reset_input_controller = reset_input_controller;
inputctl->pub.start_input_pass = start_input_pass;
inputctl->pub.finish_input_pass = finish_input_pass;
/* Initialize state: can't use reset_input_controller since we don't
* want to try to reset other modules yet.
*/
inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */
inputctl->pub.eoi_reached = FALSE;
inputctl->inheaders = 1;
}
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