| Index: third_party/libjpeg_turbo/jdinput.c
|
| ===================================================================
|
| --- third_party/libjpeg_turbo/jdinput.c (revision 0)
|
| +++ third_party/libjpeg_turbo/jdinput.c (revision 0)
|
| @@ -0,0 +1,381 @@
|
| +/*
|
| + * jdinput.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 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.
|
| + */
|
| +
|
| +#define JPEG_INTERNALS
|
| +#include "jinclude.h"
|
| +#include "jpeglib.h"
|
| +
|
| +
|
| +/* Private state */
|
| +
|
| +typedef struct {
|
| + struct jpeg_input_controller pub; /* public fields */
|
| +
|
| + boolean inheaders; /* TRUE 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.
|
| + */
|
| +
|
| +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);
|
| +
|
| + /* 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)
|
| + 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);
|
| + }
|
| +
|
| + /* We initialize DCT_scaled_size and min_DCT_scaled_size to DCTSIZE.
|
| + * 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;
|
| +
|
| + /* 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)
|
| + jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
|
| + (long) (cinfo->max_h_samp_factor * DCTSIZE));
|
| + compptr->height_in_blocks = (JDIMENSION)
|
| + jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
|
| + (long) (cinfo->max_v_samp_factor * DCTSIZE));
|
| + /* 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*DCTSIZE));
|
| +
|
| + /* 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_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*DCTSIZE));
|
| + cinfo->MCU_rows_in_scan = (JDIMENSION)
|
| + jdiv_round_up((long) cinfo->image_height,
|
| + (long) (cinfo->max_v_samp_factor*DCTSIZE));
|
| +
|
| + 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_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->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.
|
| + */
|
| +
|
| +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;
|
| +
|
| + val = (*cinfo->marker->read_markers) (cinfo);
|
| +
|
| + switch (val) {
|
| + case JPEG_REACHED_SOS: /* Found SOS */
|
| + if (inputctl->inheaders) { /* 1st SOS */
|
| + initial_setup(cinfo);
|
| + inputctl->inheaders = FALSE;
|
| + /* 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! */
|
| + start_input_pass(cinfo);
|
| + }
|
| + break;
|
| + 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;
|
| + }
|
| + break;
|
| + case JPEG_SUSPENDED:
|
| + break;
|
| + }
|
| +
|
| + 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 = TRUE;
|
| + /* 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 = (struct jpeg_input_controller *) inputctl;
|
| + /* 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 = TRUE;
|
| +}
|
|
|