diff options
Diffstat (limited to 'jpeg/jcapimin.c')
| -rw-r--r-- | jpeg/jcapimin.c | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/jpeg/jcapimin.c b/jpeg/jcapimin.c new file mode 100644 index 0000000..639ce86 --- /dev/null +++ b/jpeg/jcapimin.c @@ -0,0 +1,288 @@ +/* + * 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(). + */ +} |