170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * jcapistd.c 370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Copyright (C) 1994-1996, Thomas G. Lane. 570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * This file is part of the Independent JPEG Group's software. 670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * For conditions of distribution and use, see the accompanying README file. 770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * This file contains application interface code for the compression half 970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * of the JPEG library. These are the "standard" API routines that are 1070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * used in the normal full-compression case. They are not used by a 1170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * transcoding-only application. Note that if an application links in 1270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * jpeg_start_compress, it will end up linking in the entire compressor. 1370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * We thus must separate this file from jcapimin.c to avoid linking the 1470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * whole compression library into a transcoder. 1570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 1670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 1770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine#define JPEG_INTERNALS 1870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine#include "jinclude.h" 1970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine#include "jpeglib.h" 2070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 2170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 2270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 2370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Compression initialization. 2470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Before calling this, all parameters and a data destination must be set up. 2570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 2670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * We require a write_all_tables parameter as a failsafe check when writing 2770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * multiple datastreams from the same compression object. Since prior runs 2870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * will have left all the tables marked sent_table=TRUE, a subsequent run 2970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * would emit an abbreviated stream (no tables) by default. This may be what 3070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * is wanted, but for safety's sake it should not be the default behavior: 3170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * programmers should have to make a deliberate choice to emit abbreviated 3270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * images. Therefore the documentation and examples should encourage people 3370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * to pass write_all_tables=TRUE; then it will take active thought to do the 3470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * wrong thing. 3570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 3670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 3770a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineGLOBAL(void) 3870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkinejpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables) 3970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 4070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->global_state != CSTATE_START) 4170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); 4270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 4370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (write_all_tables) 4470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine jpeg_suppress_tables(cinfo, FALSE); /* mark all tables to be written */ 4570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 4670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* (Re)initialize error mgr and destination modules */ 4770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo); 4870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->dest->init_destination) (cinfo); 4970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Perform master selection of active modules */ 5070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine jinit_compress_master(cinfo); 5170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Set up for the first pass */ 5270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->master->prepare_for_pass) (cinfo); 5370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Ready for application to drive first pass through jpeg_write_scanlines 5470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * or jpeg_write_raw_data. 5570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 5670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->next_scanline = 0; 5770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING); 5870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 5970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 6070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 6170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 6270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Write some scanlines of data to the JPEG compressor. 6370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 6470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * The return value will be the number of lines actually written. 6570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * This should be less than the supplied num_lines only in case that 6670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * the data destination module has requested suspension of the compressor, 6770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * or if more than image_height scanlines are passed in. 6870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 6970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Note: we warn about excess calls to jpeg_write_scanlines() since 7070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * this likely signals an application programmer error. However, 7170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * excess scanlines passed in the last valid call are *silently* ignored, 7270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * so that the application need not adjust num_lines for end-of-image 7370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * when using a multiple-scanline buffer. 7470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 7570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 7670a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineGLOBAL(JDIMENSION) 7770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkinejpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines, 7870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine JDIMENSION num_lines) 7970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 8070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine JDIMENSION row_ctr, rows_left; 8170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 8270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->global_state != CSTATE_SCANNING) 8370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); 8470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->next_scanline >= cinfo->image_height) 8570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine WARNMS(cinfo, JWRN_TOO_MUCH_DATA); 8670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 8770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Call progress monitor hook if present */ 8870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->progress != NULL) { 8970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->progress->pass_counter = (long) cinfo->next_scanline; 9070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->progress->pass_limit = (long) cinfo->image_height; 9170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); 9270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 9370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 9470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Give master control module another chance if this is first call to 9570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * jpeg_write_scanlines. This lets output of the frame/scan headers be 9670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * delayed so that application can write COM, etc, markers between 9770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * jpeg_start_compress and jpeg_write_scanlines. 9870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 9970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->master->call_pass_startup) 10070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->master->pass_startup) (cinfo); 10170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 10270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Ignore any extra scanlines at bottom of image. */ 10370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine rows_left = cinfo->image_height - cinfo->next_scanline; 10470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (num_lines > rows_left) 10570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine num_lines = rows_left; 10670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 10770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine row_ctr = 0; 10870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines); 10970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->next_scanline += row_ctr; 11070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine return row_ctr; 11170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 11270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 11370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 11470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 11570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Alternate entry point to write raw data. 11670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Processes exactly one iMCU row per call, unless suspended. 11770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 11870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 11970a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineGLOBAL(JDIMENSION) 12070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkinejpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data, 12170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine JDIMENSION num_lines) 12270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 12370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine JDIMENSION lines_per_iMCU_row; 12470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 12570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->global_state != CSTATE_RAW_OK) 12670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); 12770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->next_scanline >= cinfo->image_height) { 12870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine WARNMS(cinfo, JWRN_TOO_MUCH_DATA); 12970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine return 0; 13070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 13170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 13270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Call progress monitor hook if present */ 13370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->progress != NULL) { 13470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->progress->pass_counter = (long) cinfo->next_scanline; 13570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->progress->pass_limit = (long) cinfo->image_height; 13670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); 13770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 13870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 13970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Give master control module another chance if this is first call to 14070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * jpeg_write_raw_data. This lets output of the frame/scan headers be 14170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * delayed so that application can write COM, etc, markers between 14270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * jpeg_start_compress and jpeg_write_raw_data. 14370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 14470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->master->call_pass_startup) 14570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->master->pass_startup) (cinfo); 14670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 14770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Verify that at least one iMCU row has been passed. */ 14870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine lines_per_iMCU_row = cinfo->max_v_samp_factor * DCTSIZE; 14970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (num_lines < lines_per_iMCU_row) 15070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine ERREXIT(cinfo, JERR_BUFFER_SIZE); 15170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 15270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Directly compress the row. */ 15370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (! (*cinfo->coef->compress_data) (cinfo, data)) { 15470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* If compressor did not consume the whole row, suspend processing. */ 15570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine return 0; 15670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 15770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 15870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* OK, we processed one iMCU row. */ 15970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->next_scanline += lines_per_iMCU_row; 16070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine return lines_per_iMCU_row; 16170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 162