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IJG's JPEG software v6b with lossless JPEG support

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Patch obtained from:
https://sourceforge.net/projects/jpeg/files/ftp.oceana.com

Author date taken from original announcement and timestamp of patch
tarball:
https://groups.google.com/g/comp.protocols.dicom/c/rrkP8BxoMRk/m/Ij4dfprggp8J
This commit is contained in:
Ken Murchison
1999-04-27 00:00:00 +00:00
committed by DRC
parent 5ead57a34a
commit 2e8360e061
62 changed files with 5551 additions and 1840 deletions
Download Patch File Download Diff File Expand all files Collapse all files

144
jdinput.c
View File

@@ -1,14 +1,15 @@
/*
* jdinput.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* Copyright (C) 1991-1998, 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 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 jdphuff.c.
* processing (marker reading and coefficient/difference decoding).
* The actual input reading is done in jdmarker.c, jdhuff.c, jdphuff.c,
* and jdlhuff.c.
*/
#define JPEG_INTERNALS
@@ -47,9 +48,17 @@ initial_setup (j_decompress_ptr cinfo)
(long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
/* For now, precision must match compiled-in value... */
if (cinfo->data_precision != BITS_IN_JSAMPLE)
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
if (cinfo->process == JPROC_LOSSLESS) {
/* If precision > compiled-in value, we must downscale */
if (cinfo->data_precision > BITS_IN_JSAMPLE)
WARNMS2(cinfo, JWRN_MUST_DOWNSCALE,
cinfo->data_precision, BITS_IN_JSAMPLE);
}
else { /* Lossy processes */
/* For now, precision must match compiled-in value... */
if (cinfo->data_precision != BITS_IN_JSAMPLE)
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)
@@ -70,23 +79,23 @@ initial_setup (j_decompress_ptr cinfo)
compptr->v_samp_factor);
}
/* We initialize DCT_scaled_size and min_DCT_scaled_size to DCTSIZE.
/* We initialize codec_data_unit and min_codec_data_unit to data_unit.
* In the full decompressor, this will be overridden by jdmaster.c;
* but in the transcoder, jdmaster.c is not used, so we must do it here.
*/
cinfo->min_DCT_scaled_size = DCTSIZE;
cinfo->min_codec_data_unit = cinfo->data_unit;
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_scaled_size = DCTSIZE;
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
compptr->codec_data_unit = cinfo->data_unit;
/* Size in data units */
compptr->width_in_data_units = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->height_in_blocks = (JDIMENSION)
(long) (cinfo->max_h_samp_factor * cinfo->data_unit));
compptr->height_in_data_units = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) (cinfo->max_v_samp_factor * DCTSIZE));
(long) (cinfo->max_v_samp_factor * cinfo->data_unit));
/* 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.
@@ -107,10 +116,11 @@ initial_setup (j_decompress_ptr cinfo)
/* 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*DCTSIZE));
(long) (cinfo->max_v_samp_factor*cinfo->data_unit));
/* Decide whether file contains multiple scans */
if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode)
if (cinfo->comps_in_scan < cinfo->num_components ||
cinfo->process == JPROC_PROGRESSIVE)
cinfo->inputctl->has_multiple_scans = TRUE;
else
cinfo->inputctl->has_multiple_scans = FALSE;
@@ -124,31 +134,31 @@ per_scan_setup (j_decompress_ptr cinfo)
{
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;
cinfo->MCUs_per_row = compptr->width_in_data_units;
cinfo->MCU_rows_in_scan = compptr->height_in_data_units;
/* For noninterleaved scan, always one block per MCU */
/* For noninterleaved scan, always one data unit per MCU */
compptr->MCU_width = 1;
compptr->MCU_height = 1;
compptr->MCU_blocks = 1;
compptr->MCU_sample_width = compptr->DCT_scaled_size;
compptr->MCU_data_units = 1;
compptr->MCU_sample_width = compptr->codec_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.
* as the number of data unit rows present in the last iMCU row.
*/
tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
tmp = (int) (compptr->height_in_data_units % 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->data_units_in_MCU = 1;
cinfo->MCU_membership[0] = 0;
} else {
@@ -161,33 +171,33 @@ per_scan_setup (j_decompress_ptr cinfo)
/* Overall image size in MCUs */
cinfo->MCUs_per_row = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width,
(long) (cinfo->max_h_samp_factor*DCTSIZE));
(long) (cinfo->max_h_samp_factor*cinfo->data_unit));
cinfo->MCU_rows_in_scan = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
(long) (cinfo->max_v_samp_factor*cinfo->data_unit));
cinfo->blocks_in_MCU = 0;
cinfo->data_units_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 */
/* Sampling factors give # of data units 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_scaled_size;
/* Figure number of non-dummy blocks in last MCU column & row */
tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
compptr->MCU_data_units = compptr->MCU_width * compptr->MCU_height;
compptr->MCU_sample_width = compptr->MCU_width * compptr->codec_data_unit;
/* Figure number of non-dummy data units in last MCU column & row */
tmp = (int) (compptr->width_in_data_units % compptr->MCU_width);
if (tmp == 0) tmp = compptr->MCU_width;
compptr->last_col_width = tmp;
tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
tmp = (int) (compptr->height_in_data_units % 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)
mcublks = compptr->MCU_data_units;
if (cinfo->data_units_in_MCU + mcublks > D_MAX_DATA_UNITS_IN_MCU)
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
while (mcublks-- > 0) {
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
cinfo->MCU_membership[cinfo->data_units_in_MCU++] = ci;
}
}
@@ -195,54 +205,6 @@ per_scan_setup (j_decompress_ptr cinfo)
}
/*
* 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
@@ -254,10 +216,8 @@ 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;
(*cinfo->codec->start_input_pass) (cinfo);
cinfo->inputctl->consume_input = cinfo->codec->consume_data;
}
@@ -299,6 +259,12 @@ consume_markers (j_decompress_ptr cinfo)
case JPEG_REACHED_SOS: /* Found SOS */
if (inputctl->inheaders) { /* 1st SOS */
initial_setup(cinfo);
/*
* Initialize the decompression codec. We need to do this here so that
* any codec-specific fields and function pointers are available to
* the rest of the library.
*/
jinit_d_codec(cinfo);
inputctl->inheaders = FALSE;
/* Note: start_input_pass must be called by jdmaster.c
* before any more input can be consumed. jdapimin.c is