678 lines
23 KiB
C
678 lines
23 KiB
C
/*
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* jcmaster.c
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*
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* Copyright (C) 1991-1997, Thomas G. Lane.
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* Modified 2003-2019 by Guido Vollbeding.
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* This file is part of the Independent JPEG Group's software.
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* For conditions of distribution and use, see the accompanying README file.
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*
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* This file contains master control logic for the JPEG compressor.
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* These routines are concerned with parameter validation, initial setup,
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* and inter-pass control (determining the number of passes and the work
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* to be done in each pass).
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*/
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#define JPEG_INTERNALS
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#include "jinclude.h"
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#include "jpeglib.h"
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/* Private state */
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typedef enum {
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main_pass, /* input data, also do first output step */
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huff_opt_pass, /* Huffman code optimization pass */
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output_pass /* data output pass */
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} c_pass_type;
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typedef struct {
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struct jpeg_comp_master pub; /* public fields */
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c_pass_type pass_type; /* the type of the current pass */
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int pass_number; /* # of passes completed */
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int total_passes; /* total # of passes needed */
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int scan_number; /* current index in scan_info[] */
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} my_comp_master;
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typedef my_comp_master * my_master_ptr;
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/*
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* Support routines that do various essential calculations.
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*/
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LOCAL(void)
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initial_setup (j_compress_ptr cinfo)
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/* Do computations that are needed before master selection phase */
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{
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int ci, ssize;
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jpeg_component_info *compptr;
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/* Sanity check on block_size */
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if (cinfo->block_size < 1 || cinfo->block_size > 16)
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ERREXIT2(cinfo, JERR_BAD_DCTSIZE, cinfo->block_size, cinfo->block_size);
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/* Derive natural_order from block_size */
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switch (cinfo->block_size) {
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case 2: cinfo->natural_order = jpeg_natural_order2; break;
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case 3: cinfo->natural_order = jpeg_natural_order3; break;
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case 4: cinfo->natural_order = jpeg_natural_order4; break;
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case 5: cinfo->natural_order = jpeg_natural_order5; break;
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case 6: cinfo->natural_order = jpeg_natural_order6; break;
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case 7: cinfo->natural_order = jpeg_natural_order7; break;
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default: cinfo->natural_order = jpeg_natural_order;
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}
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/* Derive lim_Se from block_size */
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cinfo->lim_Se = cinfo->block_size < DCTSIZE ?
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cinfo->block_size * cinfo->block_size - 1 : DCTSIZE2-1;
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/* Sanity check on image dimensions */
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if (cinfo->jpeg_height <= 0 || cinfo->jpeg_width <= 0 ||
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cinfo->num_components <= 0)
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ERREXIT(cinfo, JERR_EMPTY_IMAGE);
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/* Make sure image isn't bigger than I can handle */
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if ((long) cinfo->jpeg_height > (long) JPEG_MAX_DIMENSION ||
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(long) cinfo->jpeg_width > (long) JPEG_MAX_DIMENSION)
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ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
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/* Only 8 to 12 bits data precision are supported for DCT based JPEG */
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if (cinfo->data_precision < 8 || cinfo->data_precision > 12)
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ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
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/* Check that number of components won't exceed internal array sizes */
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if (cinfo->num_components > MAX_COMPONENTS)
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ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
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MAX_COMPONENTS);
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/* Compute maximum sampling factors; check factor validity */
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cinfo->max_h_samp_factor = 1;
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cinfo->max_v_samp_factor = 1;
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for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
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ci++, compptr++) {
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if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
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compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
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ERREXIT(cinfo, JERR_BAD_SAMPLING);
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cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
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compptr->h_samp_factor);
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cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
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compptr->v_samp_factor);
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}
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/* Compute dimensions of components */
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for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
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ci++, compptr++) {
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/* Fill in the correct component_index value; don't rely on application */
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compptr->component_index = ci;
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/* In selecting the actual DCT scaling for each component, we try to
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* scale down the chroma components via DCT scaling rather than downsampling.
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* This saves time if the downsampler gets to use 1:1 scaling.
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* Note this code adapts subsampling ratios which are powers of 2.
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*/
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ssize = 1;
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#ifdef DCT_SCALING_SUPPORTED
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if (! cinfo->raw_data_in)
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while (cinfo->min_DCT_h_scaled_size * ssize <=
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(cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
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(cinfo->max_h_samp_factor % (compptr->h_samp_factor * ssize * 2)) ==
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0) {
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ssize = ssize * 2;
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}
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#endif
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compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size * ssize;
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ssize = 1;
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#ifdef DCT_SCALING_SUPPORTED
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if (! cinfo->raw_data_in)
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while (cinfo->min_DCT_v_scaled_size * ssize <=
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(cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
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(cinfo->max_v_samp_factor % (compptr->v_samp_factor * ssize * 2)) ==
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0) {
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ssize = ssize * 2;
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}
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#endif
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compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size * ssize;
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/* We don't support DCT ratios larger than 2. */
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if (compptr->DCT_h_scaled_size > compptr->DCT_v_scaled_size * 2)
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compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size * 2;
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else if (compptr->DCT_v_scaled_size > compptr->DCT_h_scaled_size * 2)
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compptr->DCT_v_scaled_size = compptr->DCT_h_scaled_size * 2;
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/* Size in DCT blocks */
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compptr->width_in_blocks = (JDIMENSION)
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jdiv_round_up((long) cinfo->jpeg_width * (long) compptr->h_samp_factor,
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(long) (cinfo->max_h_samp_factor * cinfo->block_size));
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compptr->height_in_blocks = (JDIMENSION)
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jdiv_round_up((long) cinfo->jpeg_height * (long) compptr->v_samp_factor,
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(long) (cinfo->max_v_samp_factor * cinfo->block_size));
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/* Size in samples */
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compptr->downsampled_width = (JDIMENSION)
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jdiv_round_up((long) cinfo->jpeg_width *
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(long) (compptr->h_samp_factor * compptr->DCT_h_scaled_size),
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(long) (cinfo->max_h_samp_factor * cinfo->block_size));
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compptr->downsampled_height = (JDIMENSION)
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jdiv_round_up((long) cinfo->jpeg_height *
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(long) (compptr->v_samp_factor * compptr->DCT_v_scaled_size),
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(long) (cinfo->max_v_samp_factor * cinfo->block_size));
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/* Don't need quantization scale after DCT,
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* until color conversion says otherwise.
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*/
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compptr->component_needed = FALSE;
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}
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/* Compute number of fully interleaved MCU rows (number of times that
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* main controller will call coefficient controller).
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*/
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cinfo->total_iMCU_rows = (JDIMENSION)
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jdiv_round_up((long) cinfo->jpeg_height,
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(long) (cinfo->max_v_samp_factor * cinfo->block_size));
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}
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#ifdef C_MULTISCAN_FILES_SUPPORTED
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LOCAL(void)
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validate_script (j_compress_ptr cinfo)
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/* Verify that the scan script in cinfo->scan_info[] is valid; also
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* determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
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*/
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{
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const jpeg_scan_info * scanptr;
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int scanno, ncomps, ci, coefi, thisi;
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int Ss, Se, Ah, Al;
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boolean component_sent[MAX_COMPONENTS];
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#ifdef C_PROGRESSIVE_SUPPORTED
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int * last_bitpos_ptr;
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int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
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/* -1 until that coefficient has been seen; then last Al for it */
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#endif
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if (cinfo->num_scans <= 0)
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ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
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/* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
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* for progressive JPEG, no scan can have this.
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*/
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scanptr = cinfo->scan_info;
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if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {
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#ifdef C_PROGRESSIVE_SUPPORTED
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cinfo->progressive_mode = TRUE;
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last_bitpos_ptr = & last_bitpos[0][0];
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for (ci = 0; ci < cinfo->num_components; ci++)
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for (coefi = 0; coefi < DCTSIZE2; coefi++)
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*last_bitpos_ptr++ = -1;
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#else
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ERREXIT(cinfo, JERR_NOT_COMPILED);
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#endif
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} else {
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cinfo->progressive_mode = FALSE;
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for (ci = 0; ci < cinfo->num_components; ci++)
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component_sent[ci] = FALSE;
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}
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for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
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/* Validate component indexes */
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ncomps = scanptr->comps_in_scan;
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if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
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ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
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for (ci = 0; ci < ncomps; ci++) {
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thisi = scanptr->component_index[ci];
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if (thisi < 0 || thisi >= cinfo->num_components)
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ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
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/* Components must appear in SOF order within each scan */
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if (ci > 0 && thisi <= scanptr->component_index[ci-1])
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ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
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}
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/* Validate progression parameters */
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Ss = scanptr->Ss;
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Se = scanptr->Se;
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Ah = scanptr->Ah;
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Al = scanptr->Al;
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if (cinfo->progressive_mode) {
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#ifdef C_PROGRESSIVE_SUPPORTED
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/* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
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* seems wrong: the upper bound ought to depend on data precision.
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* Perhaps they really meant 0..N+1 for N-bit precision.
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* Here we allow 0..10 for 8-bit data; Al larger than 10 results in
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* out-of-range reconstructed DC values during the first DC scan,
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* which might cause problems for some decoders.
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*/
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if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
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Ah < 0 || Ah > (cinfo->data_precision > 8 ? 13 : 10) ||
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Al < 0 || Al > (cinfo->data_precision > 8 ? 13 : 10))
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ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
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if (Ss == 0) {
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if (Se != 0) /* DC and AC together not OK */
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ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
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} else {
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if (ncomps != 1) /* AC scans must be for only one component */
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ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
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}
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for (ci = 0; ci < ncomps; ci++) {
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last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];
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if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
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ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
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for (coefi = Ss; coefi <= Se; coefi++) {
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if (last_bitpos_ptr[coefi] < 0) {
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/* first scan of this coefficient */
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if (Ah != 0)
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ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
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} else {
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/* not first scan */
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if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)
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ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
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}
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last_bitpos_ptr[coefi] = Al;
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}
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}
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#endif
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} else {
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/* For sequential JPEG, all progression parameters must be these: */
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if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)
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ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
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/* Make sure components are not sent twice */
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for (ci = 0; ci < ncomps; ci++) {
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thisi = scanptr->component_index[ci];
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if (component_sent[thisi])
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ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
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component_sent[thisi] = TRUE;
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}
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}
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}
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/* Now verify that everything got sent. */
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if (cinfo->progressive_mode) {
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#ifdef C_PROGRESSIVE_SUPPORTED
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/* For progressive mode, we only check that at least some DC data
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* got sent for each component; the spec does not require that all bits
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* of all coefficients be transmitted. Would it be wiser to enforce
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* transmission of all coefficient bits??
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*/
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for (ci = 0; ci < cinfo->num_components; ci++) {
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if (last_bitpos[ci][0] < 0)
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ERREXIT(cinfo, JERR_MISSING_DATA);
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}
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#endif
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} else {
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for (ci = 0; ci < cinfo->num_components; ci++) {
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if (! component_sent[ci])
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ERREXIT(cinfo, JERR_MISSING_DATA);
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}
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}
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}
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LOCAL(void)
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reduce_script (j_compress_ptr cinfo)
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/* Adapt scan script for use with reduced block size;
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* assume that script has been validated before.
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*/
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{
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jpeg_scan_info * scanptr;
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int idxout, idxin;
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/* Circumvent const declaration for this function */
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scanptr = (jpeg_scan_info *) cinfo->scan_info;
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idxout = 0;
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for (idxin = 0; idxin < cinfo->num_scans; idxin++) {
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/* After skipping, idxout becomes smaller than idxin */
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if (idxin != idxout)
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/* Copy rest of data;
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* note we stay in given chunk of allocated memory.
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*/
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scanptr[idxout] = scanptr[idxin];
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if (scanptr[idxout].Ss > cinfo->lim_Se)
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/* Entire scan out of range - skip this entry */
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continue;
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if (scanptr[idxout].Se > cinfo->lim_Se)
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/* Limit scan to end of block */
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scanptr[idxout].Se = cinfo->lim_Se;
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idxout++;
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}
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cinfo->num_scans = idxout;
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}
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#endif /* C_MULTISCAN_FILES_SUPPORTED */
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LOCAL(void)
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select_scan_parameters (j_compress_ptr cinfo)
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/* Set up the scan parameters for the current scan */
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{
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int ci;
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#ifdef C_MULTISCAN_FILES_SUPPORTED
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if (cinfo->scan_info != NULL) {
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/* Prepare for current scan --- the script is already validated */
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my_master_ptr master = (my_master_ptr) cinfo->master;
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const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;
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cinfo->comps_in_scan = scanptr->comps_in_scan;
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for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
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cinfo->cur_comp_info[ci] =
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&cinfo->comp_info[scanptr->component_index[ci]];
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}
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if (cinfo->progressive_mode) {
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cinfo->Ss = scanptr->Ss;
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cinfo->Se = scanptr->Se;
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cinfo->Ah = scanptr->Ah;
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cinfo->Al = scanptr->Al;
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return;
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}
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}
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else
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#endif
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{
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/* Prepare for single sequential-JPEG scan containing all components */
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if (cinfo->num_components > MAX_COMPS_IN_SCAN)
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ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
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MAX_COMPS_IN_SCAN);
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cinfo->comps_in_scan = cinfo->num_components;
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for (ci = 0; ci < cinfo->num_components; ci++) {
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cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
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}
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}
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cinfo->Ss = 0;
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cinfo->Se = cinfo->block_size * cinfo->block_size - 1;
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cinfo->Ah = 0;
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cinfo->Al = 0;
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}
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LOCAL(void)
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per_scan_setup (j_compress_ptr cinfo)
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/* Do computations that are needed before processing a JPEG scan */
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/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
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{
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int ci, mcublks, tmp;
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jpeg_component_info *compptr;
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if (cinfo->comps_in_scan == 1) {
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/* Noninterleaved (single-component) scan */
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compptr = cinfo->cur_comp_info[0];
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/* Overall image size in MCUs */
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cinfo->MCUs_per_row = compptr->width_in_blocks;
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cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
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/* For noninterleaved scan, always one block per MCU */
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compptr->MCU_width = 1;
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compptr->MCU_height = 1;
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compptr->MCU_blocks = 1;
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compptr->MCU_sample_width = compptr->DCT_h_scaled_size;
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compptr->last_col_width = 1;
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/* For noninterleaved scans, it is convenient to define last_row_height
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* as the number of block rows present in the last iMCU row.
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*/
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tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
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if (tmp == 0) tmp = compptr->v_samp_factor;
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compptr->last_row_height = tmp;
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/* Prepare array describing MCU composition */
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cinfo->blocks_in_MCU = 1;
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cinfo->MCU_membership[0] = 0;
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} else {
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/* Interleaved (multi-component) scan */
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if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
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ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
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MAX_COMPS_IN_SCAN);
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/* Overall image size in MCUs */
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cinfo->MCUs_per_row = (JDIMENSION)
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jdiv_round_up((long) cinfo->jpeg_width,
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(long) (cinfo->max_h_samp_factor * cinfo->block_size));
|
|
cinfo->MCU_rows_in_scan = (JDIMENSION)
|
|
jdiv_round_up((long) cinfo->jpeg_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 > 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->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++;
|
|
/*FALLTHROUGH*/
|
|
#endif
|
|
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;
|
|
|
|
master = (my_master_ptr) (*cinfo->mem->alloc_small)
|
|
((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(my_comp_master));
|
|
cinfo->master = &master->pub;
|
|
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;
|
|
|
|
/* Validate parameters, determine derived values */
|
|
initial_setup(cinfo);
|
|
|
|
if (cinfo->scan_info != NULL) {
|
|
#ifdef C_MULTISCAN_FILES_SUPPORTED
|
|
validate_script(cinfo);
|
|
if (cinfo->block_size < DCTSIZE)
|
|
reduce_script(cinfo);
|
|
#else
|
|
ERREXIT(cinfo, JERR_NOT_COMPILED);
|
|
#endif
|
|
} else {
|
|
cinfo->progressive_mode = FALSE;
|
|
cinfo->num_scans = 1;
|
|
}
|
|
|
|
if (cinfo->optimize_coding)
|
|
cinfo->arith_code = FALSE; /* disable arithmetic coding */
|
|
else if (! cinfo->arith_code &&
|
|
(cinfo->progressive_mode ||
|
|
(cinfo->block_size > 1 && cinfo->block_size < DCTSIZE)))
|
|
/* TEMPORARY HACK ??? */
|
|
/* assume default tables no good for progressive or reduced AC mode */
|
|
cinfo->optimize_coding = TRUE; /* force Huffman optimization */
|
|
|
|
/* 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;
|
|
}
|