ref: 2c23de27d5006e969106fad672399fafe6464845
dir: /DoConfig/fltk/jpeg/jcapimin.c/
/* * jcapimin.c * * Copyright (C) 1994-1998, Thomas G. Lane. * Modified 2003-2010 by Guido Vollbeding. * 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 "minimum" API routines that may be * needed in either the normal full-compression case or the transcoding-only * case. * * Most of the routines intended to be called directly by an application * are in this file or in jcapistd.c. But also see jcparam.c for * parameter-setup helper routines, jcomapi.c for routines shared by * compression and decompression, and jctrans.c for the transcoding case. */ #define JPEG_INTERNALS #include "jinclude.h" #include "jpeglib.h" /* * Initialization of a JPEG compression object. * The error manager must already be set up (in case memory manager fails). */ GLOBAL(void) jpeg_CreateCompress (j_compress_ptr cinfo, int version, size_t structsize) { int i; /* Guard against version mismatches between library and caller. */ cinfo->mem = NULL; /* so jpeg_destroy knows mem mgr not called */ if (version != JPEG_LIB_VERSION) ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version); if (structsize != SIZEOF(struct jpeg_compress_struct)) ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE, (int) SIZEOF(struct jpeg_compress_struct), (int) structsize); /* For debugging purposes, we zero the whole master structure. * But the application has already set the err pointer, and may have set * client_data, so we have to save and restore those fields. * Note: if application hasn't set client_data, tools like Purify may * complain here. */ { struct jpeg_error_mgr * err = cinfo->err; void * client_data = cinfo->client_data; /* ignore Purify complaint here */ MEMZERO(cinfo, SIZEOF(struct jpeg_compress_struct)); cinfo->err = err; cinfo->client_data = client_data; } cinfo->is_decompressor = FALSE; /* Initialize a memory manager instance for this object */ jinit_memory_mgr((j_common_ptr) cinfo); /* Zero out pointers to permanent structures. */ cinfo->progress = NULL; cinfo->dest = NULL; cinfo->comp_info = NULL; for (i = 0; i < NUM_QUANT_TBLS; i++) { cinfo->quant_tbl_ptrs[i] = NULL; cinfo->q_scale_factor[i] = 100; } for (i = 0; i < NUM_HUFF_TBLS; i++) { cinfo->dc_huff_tbl_ptrs[i] = NULL; cinfo->ac_huff_tbl_ptrs[i] = NULL; } /* Must do it here for emit_dqt in case jpeg_write_tables is used */ cinfo->block_size = DCTSIZE; cinfo->natural_order = jpeg_natural_order; cinfo->lim_Se = DCTSIZE2-1; cinfo->script_space = NULL; cinfo->input_gamma = 1.0; /* in case application forgets */ /* OK, I'm ready */ cinfo->global_state = CSTATE_START; } /* * Destruction of a JPEG compression object */ GLOBAL(void) jpeg_destroy_compress (j_compress_ptr cinfo) { jpeg_destroy((j_common_ptr) cinfo); /* use common routine */ } /* * Abort processing of a JPEG compression operation, * but don't destroy the object itself. */ GLOBAL(void) jpeg_abort_compress (j_compress_ptr cinfo) { jpeg_abort((j_common_ptr) cinfo); /* use common routine */ } /* * Forcibly suppress or un-suppress all quantization and Huffman tables. * Marks all currently defined tables as already written (if suppress) * or not written (if !suppress). This will control whether they get emitted * by a subsequent jpeg_start_compress call. * * This routine is exported for use by applications that want to produce * abbreviated JPEG datastreams. It logically belongs in jcparam.c, but * since it is called by jpeg_start_compress, we put it here --- otherwise * jcparam.o would be linked whether the application used it or not. */ GLOBAL(void) jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress) { int i; JQUANT_TBL * qtbl; JHUFF_TBL * htbl; for (i = 0; i < NUM_QUANT_TBLS; i++) { if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL) qtbl->sent_table = suppress; } for (i = 0; i < NUM_HUFF_TBLS; i++) { if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL) htbl->sent_table = suppress; if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL) htbl->sent_table = suppress; } } /* * Finish JPEG compression. * * If a multipass operating mode was selected, this may do a great deal of * work including most of the actual output. */ GLOBAL(void) jpeg_finish_compress (j_compress_ptr cinfo) { JDIMENSION iMCU_row; if (cinfo->global_state == CSTATE_SCANNING || cinfo->global_state == CSTATE_RAW_OK) { /* Terminate first pass */ if (cinfo->next_scanline < cinfo->image_height) ERREXIT(cinfo, JERR_TOO_LITTLE_DATA); (*cinfo->master->finish_pass) (cinfo); } else if (cinfo->global_state != CSTATE_WRCOEFS) ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); /* Perform any remaining passes */ while (! cinfo->master->is_last_pass) { (*cinfo->master->prepare_for_pass) (cinfo); for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) { if (cinfo->progress != NULL) { cinfo->progress->pass_counter = (long) iMCU_row; cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows; (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); } /* We bypass the main controller and invoke coef controller directly; * all work is being done from the coefficient buffer. */ if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL)) ERREXIT(cinfo, JERR_CANT_SUSPEND); } (*cinfo->master->finish_pass) (cinfo); } /* Write EOI, do final cleanup */ (*cinfo->marker->write_file_trailer) (cinfo); (*cinfo->dest->term_destination) (cinfo); /* We can use jpeg_abort to release memory and reset global_state */ jpeg_abort((j_common_ptr) cinfo); } /* * Write a special marker. * This is only recommended for writing COM or APPn markers. * Must be called after jpeg_start_compress() and before * first call to jpeg_write_scanlines() or jpeg_write_raw_data(). */ GLOBAL(void) jpeg_write_marker (j_compress_ptr cinfo, int marker, const JOCTET *dataptr, unsigned int datalen) { JMETHOD(void, write_marker_byte, (j_compress_ptr info, int val)); if (cinfo->next_scanline != 0 || (cinfo->global_state != CSTATE_SCANNING && cinfo->global_state != CSTATE_RAW_OK && cinfo->global_state != CSTATE_WRCOEFS)) ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); (*cinfo->marker->write_marker_header) (cinfo, marker, datalen); write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */ while (datalen--) { (*write_marker_byte) (cinfo, *dataptr); dataptr++; } } /* Same, but piecemeal. */ GLOBAL(void) jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen) { if (cinfo->next_scanline != 0 || (cinfo->global_state != CSTATE_SCANNING && cinfo->global_state != CSTATE_RAW_OK && cinfo->global_state != CSTATE_WRCOEFS)) ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); (*cinfo->marker->write_marker_header) (cinfo, marker, datalen); } GLOBAL(void) jpeg_write_m_byte (j_compress_ptr cinfo, int val) { (*cinfo->marker->write_marker_byte) (cinfo, val); } /* * Alternate compression function: just write an abbreviated table file. * Before calling this, all parameters and a data destination must be set up. * * To produce a pair of files containing abbreviated tables and abbreviated * image data, one would proceed as follows: * * initialize JPEG object * set JPEG parameters * set destination to table file * jpeg_write_tables(cinfo); * set destination to image file * jpeg_start_compress(cinfo, FALSE); * write data... * jpeg_finish_compress(cinfo); * * jpeg_write_tables has the side effect of marking all tables written * (same as jpeg_suppress_tables(..., TRUE)). Thus a subsequent start_compress * will not re-emit the tables unless it is passed write_all_tables=TRUE. */ GLOBAL(void) jpeg_write_tables (j_compress_ptr cinfo) { if (cinfo->global_state != CSTATE_START) ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); /* (Re)initialize error mgr and destination modules */ (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo); (*cinfo->dest->init_destination) (cinfo); /* Initialize the marker writer ... bit of a crock to do it here. */ jinit_marker_writer(cinfo); /* Write them tables! */ (*cinfo->marker->write_tables_only) (cinfo); /* And clean up. */ (*cinfo->dest->term_destination) (cinfo); /* * In library releases up through v6a, we called jpeg_abort() here to free * any working memory allocated by the destination manager and marker * writer. Some applications had a problem with that: they allocated space * of their own from the library memory manager, and didn't want it to go * away during write_tables. So now we do nothing. This will cause a * memory leak if an app calls write_tables repeatedly without doing a full * compression cycle or otherwise resetting the JPEG object. However, that * seems less bad than unexpectedly freeing memory in the normal case. * An app that prefers the old behavior can call jpeg_abort for itself after * each call to jpeg_write_tables(). */ }