vrshoot
diff libs/libjpeg/jcapistd.c @ 0:b2f14e535253
initial commit
author | John Tsiombikas <nuclear@member.fsf.org> |
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date | Sat, 01 Feb 2014 19:58:19 +0200 |
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1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/libs/libjpeg/jcapistd.c Sat Feb 01 19:58:19 2014 +0200 1.3 @@ -0,0 +1,161 @@ 1.4 +/* 1.5 + * jcapistd.c 1.6 + * 1.7 + * Copyright (C) 1994-1996, Thomas G. Lane. 1.8 + * This file is part of the Independent JPEG Group's software. 1.9 + * For conditions of distribution and use, see the accompanying README file. 1.10 + * 1.11 + * This file contains application interface code for the compression half 1.12 + * of the JPEG library. These are the "standard" API routines that are 1.13 + * used in the normal full-compression case. They are not used by a 1.14 + * transcoding-only application. Note that if an application links in 1.15 + * jpeg_start_compress, it will end up linking in the entire compressor. 1.16 + * We thus must separate this file from jcapimin.c to avoid linking the 1.17 + * whole compression library into a transcoder. 1.18 + */ 1.19 + 1.20 +#define JPEG_INTERNALS 1.21 +#include "jinclude.h" 1.22 +#include "jpeglib.h" 1.23 + 1.24 + 1.25 +/* 1.26 + * Compression initialization. 1.27 + * Before calling this, all parameters and a data destination must be set up. 1.28 + * 1.29 + * We require a write_all_tables parameter as a failsafe check when writing 1.30 + * multiple datastreams from the same compression object. Since prior runs 1.31 + * will have left all the tables marked sent_table=TRUE, a subsequent run 1.32 + * would emit an abbreviated stream (no tables) by default. This may be what 1.33 + * is wanted, but for safety's sake it should not be the default behavior: 1.34 + * programmers should have to make a deliberate choice to emit abbreviated 1.35 + * images. Therefore the documentation and examples should encourage people 1.36 + * to pass write_all_tables=TRUE; then it will take active thought to do the 1.37 + * wrong thing. 1.38 + */ 1.39 + 1.40 +GLOBAL(void) 1.41 +jpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables) 1.42 +{ 1.43 + if (cinfo->global_state != CSTATE_START) 1.44 + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); 1.45 + 1.46 + if (write_all_tables) 1.47 + jpeg_suppress_tables(cinfo, FALSE); /* mark all tables to be written */ 1.48 + 1.49 + /* (Re)initialize error mgr and destination modules */ 1.50 + (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo); 1.51 + (*cinfo->dest->init_destination) (cinfo); 1.52 + /* Perform master selection of active modules */ 1.53 + jinit_compress_master(cinfo); 1.54 + /* Set up for the first pass */ 1.55 + (*cinfo->master->prepare_for_pass) (cinfo); 1.56 + /* Ready for application to drive first pass through jpeg_write_scanlines 1.57 + * or jpeg_write_raw_data. 1.58 + */ 1.59 + cinfo->next_scanline = 0; 1.60 + cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING); 1.61 +} 1.62 + 1.63 + 1.64 +/* 1.65 + * Write some scanlines of data to the JPEG compressor. 1.66 + * 1.67 + * The return value will be the number of lines actually written. 1.68 + * This should be less than the supplied num_lines only in case that 1.69 + * the data destination module has requested suspension of the compressor, 1.70 + * or if more than image_height scanlines are passed in. 1.71 + * 1.72 + * Note: we warn about excess calls to jpeg_write_scanlines() since 1.73 + * this likely signals an application programmer error. However, 1.74 + * excess scanlines passed in the last valid call are *silently* ignored, 1.75 + * so that the application need not adjust num_lines for end-of-image 1.76 + * when using a multiple-scanline buffer. 1.77 + */ 1.78 + 1.79 +GLOBAL(JDIMENSION) 1.80 +jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines, 1.81 + JDIMENSION num_lines) 1.82 +{ 1.83 + JDIMENSION row_ctr, rows_left; 1.84 + 1.85 + if (cinfo->global_state != CSTATE_SCANNING) 1.86 + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); 1.87 + if (cinfo->next_scanline >= cinfo->image_height) 1.88 + WARNMS(cinfo, JWRN_TOO_MUCH_DATA); 1.89 + 1.90 + /* Call progress monitor hook if present */ 1.91 + if (cinfo->progress != NULL) { 1.92 + cinfo->progress->pass_counter = (long) cinfo->next_scanline; 1.93 + cinfo->progress->pass_limit = (long) cinfo->image_height; 1.94 + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); 1.95 + } 1.96 + 1.97 + /* Give master control module another chance if this is first call to 1.98 + * jpeg_write_scanlines. This lets output of the frame/scan headers be 1.99 + * delayed so that application can write COM, etc, markers between 1.100 + * jpeg_start_compress and jpeg_write_scanlines. 1.101 + */ 1.102 + if (cinfo->master->call_pass_startup) 1.103 + (*cinfo->master->pass_startup) (cinfo); 1.104 + 1.105 + /* Ignore any extra scanlines at bottom of image. */ 1.106 + rows_left = cinfo->image_height - cinfo->next_scanline; 1.107 + if (num_lines > rows_left) 1.108 + num_lines = rows_left; 1.109 + 1.110 + row_ctr = 0; 1.111 + (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines); 1.112 + cinfo->next_scanline += row_ctr; 1.113 + return row_ctr; 1.114 +} 1.115 + 1.116 + 1.117 +/* 1.118 + * Alternate entry point to write raw data. 1.119 + * Processes exactly one iMCU row per call, unless suspended. 1.120 + */ 1.121 + 1.122 +GLOBAL(JDIMENSION) 1.123 +jpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data, 1.124 + JDIMENSION num_lines) 1.125 +{ 1.126 + JDIMENSION lines_per_iMCU_row; 1.127 + 1.128 + if (cinfo->global_state != CSTATE_RAW_OK) 1.129 + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); 1.130 + if (cinfo->next_scanline >= cinfo->image_height) { 1.131 + WARNMS(cinfo, JWRN_TOO_MUCH_DATA); 1.132 + return 0; 1.133 + } 1.134 + 1.135 + /* Call progress monitor hook if present */ 1.136 + if (cinfo->progress != NULL) { 1.137 + cinfo->progress->pass_counter = (long) cinfo->next_scanline; 1.138 + cinfo->progress->pass_limit = (long) cinfo->image_height; 1.139 + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); 1.140 + } 1.141 + 1.142 + /* Give master control module another chance if this is first call to 1.143 + * jpeg_write_raw_data. This lets output of the frame/scan headers be 1.144 + * delayed so that application can write COM, etc, markers between 1.145 + * jpeg_start_compress and jpeg_write_raw_data. 1.146 + */ 1.147 + if (cinfo->master->call_pass_startup) 1.148 + (*cinfo->master->pass_startup) (cinfo); 1.149 + 1.150 + /* Verify that at least one iMCU row has been passed. */ 1.151 + lines_per_iMCU_row = cinfo->max_v_samp_factor * DCTSIZE; 1.152 + if (num_lines < lines_per_iMCU_row) 1.153 + ERREXIT(cinfo, JERR_BUFFER_SIZE); 1.154 + 1.155 + /* Directly compress the row. */ 1.156 + if (! (*cinfo->coef->compress_data) (cinfo, data)) { 1.157 + /* If compressor did not consume the whole row, suspend processing. */ 1.158 + return 0; 1.159 + } 1.160 + 1.161 + /* OK, we processed one iMCU row. */ 1.162 + cinfo->next_scanline += lines_per_iMCU_row; 1.163 + return lines_per_iMCU_row; 1.164 +}