| /* |
| * jcapimin.c |
| * |
| * Copyright (C) 1994-1998, 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 "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; |
| |
| for (i = 0; i < NUM_HUFF_TBLS; i++) { |
| cinfo->dc_huff_tbl_ptrs[i] = NULL; |
| cinfo->ac_huff_tbl_ptrs[i] = NULL; |
| } |
| |
| 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(). |
| */ |
| } |