+++ /dev/null
-/*
- * jcapistd.c
- *
- * Copyright (C) 1994-1996, 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 application interface code for the compression half
- * of the JPEG library. These are the "standard" API routines that are
- * used in the normal full-compression case. They are not used by a
- * transcoding-only application. Note that if an application links in
- * jpeg_start_compress, it will end up linking in the entire compressor.
- * We thus must separate this file from jcapimin.c to avoid linking the
- * whole compression library into a transcoder.
- */
-
-#define JPEG_INTERNALS
-#include "jinclude.h"
-#include "jpeglib.h"
-
-
-/*
- * Compression initialization.
- * Before calling this, all parameters and a data destination must be set up.
- *
- * We require a write_all_tables parameter as a failsafe check when writing
- * multiple datastreams from the same compression object. Since prior runs
- * will have left all the tables marked sent_table=TRUE, a subsequent run
- * would emit an abbreviated stream (no tables) by default. This may be what
- * is wanted, but for safety's sake it should not be the default behavior:
- * programmers should have to make a deliberate choice to emit abbreviated
- * images. Therefore the documentation and examples should encourage people
- * to pass write_all_tables=TRUE; then it will take active thought to do the
- * wrong thing.
- */
-
-GLOBAL(void)
-jpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables)
-{
- if (cinfo->global_state != CSTATE_START)
- ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
-
- if (write_all_tables)
- jpeg_suppress_tables(cinfo, FALSE); /* mark all tables to be written */
-
- /* (Re)initialize error mgr and destination modules */
- (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
- (*cinfo->dest->init_destination) (cinfo);
- /* Perform master selection of active modules */
- jinit_compress_master(cinfo);
- /* Set up for the first pass */
- (*cinfo->master->prepare_for_pass) (cinfo);
- /* Ready for application to drive first pass through jpeg_write_scanlines
- * or jpeg_write_raw_data.
- */
- cinfo->next_scanline = 0;
- cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING);
-}
-
-
-/*
- * Write some scanlines of data to the JPEG compressor.
- *
- * The return value will be the number of lines actually written.
- * This should be less than the supplied num_lines only in case that
- * the data destination module has requested suspension of the compressor,
- * or if more than image_height scanlines are passed in.
- *
- * Note: we warn about excess calls to jpeg_write_scanlines() since
- * this likely signals an application programmer error. However,
- * excess scanlines passed in the last valid call are *silently* ignored,
- * so that the application need not adjust num_lines for end-of-image
- * when using a multiple-scanline buffer.
- */
-
-GLOBAL(JDIMENSION)
-jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines,
- JDIMENSION num_lines)
-{
- JDIMENSION row_ctr, rows_left;
-
- if (cinfo->global_state != CSTATE_SCANNING)
- ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
- if (cinfo->next_scanline >= cinfo->image_height)
- WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
-
- /* Call progress monitor hook if present */
- if (cinfo->progress != NULL) {
- cinfo->progress->pass_counter = (long) cinfo->next_scanline;
- cinfo->progress->pass_limit = (long) cinfo->image_height;
- (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
- }
-
- /* Give master control module another chance if this is first call to
- * jpeg_write_scanlines. This lets output of the frame/scan headers be
- * delayed so that application can write COM, etc, markers between
- * jpeg_start_compress and jpeg_write_scanlines.
- */
- if (cinfo->master->call_pass_startup)
- (*cinfo->master->pass_startup) (cinfo);
-
- /* Ignore any extra scanlines at bottom of image. */
- rows_left = cinfo->image_height - cinfo->next_scanline;
- if (num_lines > rows_left)
- num_lines = rows_left;
-
- row_ctr = 0;
- (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines);
- cinfo->next_scanline += row_ctr;
- return row_ctr;
-}
-
-
-/*
- * Alternate entry point to write raw data.
- * Processes exactly one iMCU row per call, unless suspended.
- */
-
-GLOBAL(JDIMENSION)
-jpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data,
- JDIMENSION num_lines)
-{
- JDIMENSION lines_per_iMCU_row;
-
- if (cinfo->global_state != CSTATE_RAW_OK)
- ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
- if (cinfo->next_scanline >= cinfo->image_height) {
- WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
- return 0;
- }
-
- /* Call progress monitor hook if present */
- if (cinfo->progress != NULL) {
- cinfo->progress->pass_counter = (long) cinfo->next_scanline;
- cinfo->progress->pass_limit = (long) cinfo->image_height;
- (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
- }
-
- /* Give master control module another chance if this is first call to
- * jpeg_write_raw_data. This lets output of the frame/scan headers be
- * delayed so that application can write COM, etc, markers between
- * jpeg_start_compress and jpeg_write_raw_data.
- */
- if (cinfo->master->call_pass_startup)
- (*cinfo->master->pass_startup) (cinfo);
-
- /* Verify that at least one iMCU row has been passed. */
- lines_per_iMCU_row = cinfo->max_v_samp_factor * DCTSIZE;
- if (num_lines < lines_per_iMCU_row)
- ERREXIT(cinfo, JERR_BUFFER_SIZE);
-
- /* Directly compress the row. */
- if (! (*cinfo->coef->compress_data) (cinfo, data)) {
- /* If compressor did not consume the whole row, suspend processing. */
- return 0;
- }
-
- /* OK, we processed one iMCU row. */
- cinfo->next_scanline += lines_per_iMCU_row;
- return lines_per_iMCU_row;
-}
projects / opencv / blobdiff