|  | #if !defined(_FX_JPEG_TURBO_) | 
|  | /* | 
|  | * jdapistd.c | 
|  | * | 
|  | * Copyright (C) 1994-1996, 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 decompression half | 
|  | * of the JPEG library.  These are the "standard" API routines that are | 
|  | * used in the normal full-decompression case.  They are not used by a | 
|  | * transcoding-only application.  Note that if an application links in | 
|  | * jpeg_start_decompress, it will end up linking in the entire decompressor. | 
|  | * We thus must separate this file from jdapimin.c to avoid linking the | 
|  | * whole decompression library into a transcoder. | 
|  | */ | 
|  |  | 
|  | #define JPEG_INTERNALS | 
|  | #include "jinclude.h" | 
|  | #include "jpeglib.h" | 
|  |  | 
|  |  | 
|  | /* Forward declarations */ | 
|  | LOCAL(boolean) output_pass_setup JPP((j_decompress_ptr cinfo)); | 
|  |  | 
|  |  | 
|  | /* | 
|  | * Decompression initialization. | 
|  | * jpeg_read_header must be completed before calling this. | 
|  | * | 
|  | * If a multipass operating mode was selected, this will do all but the | 
|  | * last pass, and thus may take a great deal of time. | 
|  | * | 
|  | * Returns FALSE if suspended.  The return value need be inspected only if | 
|  | * a suspending data source is used. | 
|  | */ | 
|  |  | 
|  | GLOBAL(boolean) | 
|  | jpeg_start_decompress (j_decompress_ptr cinfo) | 
|  | { | 
|  | if (cinfo->global_state == DSTATE_READY) { | 
|  | /* First call: initialize master control, select active modules */ | 
|  | jinit_master_decompress(cinfo); | 
|  | if (cinfo->buffered_image) { | 
|  | /* No more work here; expecting jpeg_start_output next */ | 
|  | cinfo->global_state = DSTATE_BUFIMAGE; | 
|  | return TRUE; | 
|  | } | 
|  | cinfo->global_state = DSTATE_PRELOAD; | 
|  | } | 
|  | if (cinfo->global_state == DSTATE_PRELOAD) { | 
|  | /* If file has multiple scans, absorb them all into the coef buffer */ | 
|  | if (cinfo->inputctl->has_multiple_scans) { | 
|  | #ifdef D_MULTISCAN_FILES_SUPPORTED | 
|  | for (;;) { | 
|  | int retcode; | 
|  | /* Call progress monitor hook if present */ | 
|  | if (cinfo->progress != NULL) | 
|  | (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); | 
|  | /* Absorb some more input */ | 
|  | retcode = (*cinfo->inputctl->consume_input) (cinfo); | 
|  | if (retcode == JPEG_SUSPENDED) | 
|  | return FALSE; | 
|  | if (retcode == JPEG_REACHED_EOI) | 
|  | break; | 
|  | /* Advance progress counter if appropriate */ | 
|  | if (cinfo->progress != NULL && | 
|  | (retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) { | 
|  | if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) { | 
|  | /* jdmaster underestimated number of scans; ratchet up one scan */ | 
|  | cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows; | 
|  | } | 
|  | } | 
|  | } | 
|  | #else | 
|  | ERREXIT(cinfo, JERR_NOT_COMPILED); | 
|  | #endif /* D_MULTISCAN_FILES_SUPPORTED */ | 
|  | } | 
|  | cinfo->output_scan_number = cinfo->input_scan_number; | 
|  | } else if (cinfo->global_state != DSTATE_PRESCAN) | 
|  | ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); | 
|  | /* Perform any dummy output passes, and set up for the final pass */ | 
|  | return output_pass_setup(cinfo); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* | 
|  | * Set up for an output pass, and perform any dummy pass(es) needed. | 
|  | * Common subroutine for jpeg_start_decompress and jpeg_start_output. | 
|  | * Entry: global_state = DSTATE_PRESCAN only if previously suspended. | 
|  | * Exit: If done, returns TRUE and sets global_state for proper output mode. | 
|  | *       If suspended, returns FALSE and sets global_state = DSTATE_PRESCAN. | 
|  | */ | 
|  |  | 
|  | LOCAL(boolean) | 
|  | output_pass_setup (j_decompress_ptr cinfo) | 
|  | { | 
|  | if (cinfo->global_state != DSTATE_PRESCAN) { | 
|  | /* First call: do pass setup */ | 
|  | (*cinfo->master->prepare_for_output_pass) (cinfo); | 
|  | cinfo->output_scanline = 0; | 
|  | cinfo->global_state = DSTATE_PRESCAN; | 
|  | } | 
|  | /* Loop over any required dummy passes */ | 
|  | while (cinfo->master->is_dummy_pass) { | 
|  | #ifdef QUANT_2PASS_SUPPORTED | 
|  | /* Crank through the dummy pass */ | 
|  | while (cinfo->output_scanline < cinfo->output_height) { | 
|  | JDIMENSION last_scanline; | 
|  | /* Call progress monitor hook if present */ | 
|  | if (cinfo->progress != NULL) { | 
|  | cinfo->progress->pass_counter = (long) cinfo->output_scanline; | 
|  | cinfo->progress->pass_limit = (long) cinfo->output_height; | 
|  | (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); | 
|  | } | 
|  | /* Process some data */ | 
|  | last_scanline = cinfo->output_scanline; | 
|  | (*cinfo->main->process_data) (cinfo, (JSAMPARRAY) NULL, | 
|  | &cinfo->output_scanline, (JDIMENSION) 0); | 
|  | if (cinfo->output_scanline == last_scanline) | 
|  | return FALSE;		/* No progress made, must suspend */ | 
|  | } | 
|  | /* Finish up dummy pass, and set up for another one */ | 
|  | (*cinfo->master->finish_output_pass) (cinfo); | 
|  | (*cinfo->master->prepare_for_output_pass) (cinfo); | 
|  | cinfo->output_scanline = 0; | 
|  | #else | 
|  | ERREXIT(cinfo, JERR_NOT_COMPILED); | 
|  | #endif /* QUANT_2PASS_SUPPORTED */ | 
|  | } | 
|  | /* Ready for application to drive output pass through | 
|  | * jpeg_read_scanlines or jpeg_read_raw_data. | 
|  | */ | 
|  | cinfo->global_state = cinfo->raw_data_out ? DSTATE_RAW_OK : DSTATE_SCANNING; | 
|  | return TRUE; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* | 
|  | * Read some scanlines of data from the JPEG decompressor. | 
|  | * | 
|  | * The return value will be the number of lines actually read. | 
|  | * This may be less than the number requested in several cases, | 
|  | * including bottom of image, data source suspension, and operating | 
|  | * modes that emit multiple scanlines at a time. | 
|  | * | 
|  | * Note: we warn about excess calls to jpeg_read_scanlines() since | 
|  | * this likely signals an application programmer error.  However, | 
|  | * an oversize buffer (max_lines > scanlines remaining) is not an error. | 
|  | */ | 
|  |  | 
|  | GLOBAL(JDIMENSION) | 
|  | jpeg_read_scanlines (j_decompress_ptr cinfo, JSAMPARRAY scanlines, | 
|  | JDIMENSION max_lines) | 
|  | { | 
|  | JDIMENSION row_ctr; | 
|  |  | 
|  | if (cinfo->global_state != DSTATE_SCANNING) | 
|  | return 0; /* XYQ 2010-6-27: don't throw exception here */ | 
|  | /*    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); */ | 
|  | if (cinfo->output_scanline >= cinfo->output_height) { | 
|  | WARNMS(cinfo, JWRN_TOO_MUCH_DATA); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Call progress monitor hook if present */ | 
|  | if (cinfo->progress != NULL) { | 
|  | cinfo->progress->pass_counter = (long) cinfo->output_scanline; | 
|  | cinfo->progress->pass_limit = (long) cinfo->output_height; | 
|  | (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); | 
|  | } | 
|  |  | 
|  | /* Process some data */ | 
|  | row_ctr = 0; | 
|  | (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, max_lines); | 
|  | cinfo->output_scanline += row_ctr; | 
|  | return row_ctr; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* | 
|  | * Alternate entry point to read raw data. | 
|  | * Processes exactly one iMCU row per call, unless suspended. | 
|  | */ | 
|  |  | 
|  | GLOBAL(JDIMENSION) | 
|  | jpeg_read_raw_data (j_decompress_ptr cinfo, JSAMPIMAGE data, | 
|  | JDIMENSION max_lines) | 
|  | { | 
|  | JDIMENSION lines_per_iMCU_row; | 
|  |  | 
|  | if (cinfo->global_state != DSTATE_RAW_OK) | 
|  | ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); | 
|  | if (cinfo->output_scanline >= cinfo->output_height) { | 
|  | WARNMS(cinfo, JWRN_TOO_MUCH_DATA); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Call progress monitor hook if present */ | 
|  | if (cinfo->progress != NULL) { | 
|  | cinfo->progress->pass_counter = (long) cinfo->output_scanline; | 
|  | cinfo->progress->pass_limit = (long) cinfo->output_height; | 
|  | (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); | 
|  | } | 
|  |  | 
|  | /* Verify that at least one iMCU row can be returned. */ | 
|  | lines_per_iMCU_row = cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size; | 
|  | if (max_lines < lines_per_iMCU_row) | 
|  | ERREXIT(cinfo, JERR_BUFFER_SIZE); | 
|  |  | 
|  | /* Decompress directly into user's buffer. */ | 
|  | if (! (*cinfo->coef->decompress_data) (cinfo, data)) | 
|  | return 0;			/* suspension forced, can do nothing more */ | 
|  |  | 
|  | /* OK, we processed one iMCU row. */ | 
|  | cinfo->output_scanline += lines_per_iMCU_row; | 
|  | return lines_per_iMCU_row; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Additional entry points for buffered-image mode. */ | 
|  |  | 
|  | #ifdef D_MULTISCAN_FILES_SUPPORTED | 
|  |  | 
|  | /* | 
|  | * Initialize for an output pass in buffered-image mode. | 
|  | */ | 
|  |  | 
|  | GLOBAL(boolean) | 
|  | jpeg_start_output (j_decompress_ptr cinfo, int scan_number) | 
|  | { | 
|  | if (cinfo->global_state != DSTATE_BUFIMAGE && | 
|  | cinfo->global_state != DSTATE_PRESCAN) | 
|  | ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); | 
|  | /* Limit scan number to valid range */ | 
|  | if (scan_number <= 0) | 
|  | scan_number = 1; | 
|  | if (cinfo->inputctl->eoi_reached && | 
|  | scan_number > cinfo->input_scan_number) | 
|  | scan_number = cinfo->input_scan_number; | 
|  | cinfo->output_scan_number = scan_number; | 
|  | /* Perform any dummy output passes, and set up for the real pass */ | 
|  | return output_pass_setup(cinfo); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* | 
|  | * Finish up after an output pass in buffered-image mode. | 
|  | * | 
|  | * Returns FALSE if suspended.  The return value need be inspected only if | 
|  | * a suspending data source is used. | 
|  | */ | 
|  |  | 
|  | GLOBAL(boolean) | 
|  | jpeg_finish_output (j_decompress_ptr cinfo) | 
|  | { | 
|  | if ((cinfo->global_state == DSTATE_SCANNING || | 
|  | cinfo->global_state == DSTATE_RAW_OK) && cinfo->buffered_image) { | 
|  | /* Terminate this pass. */ | 
|  | /* We do not require the whole pass to have been completed. */ | 
|  | (*cinfo->master->finish_output_pass) (cinfo); | 
|  | cinfo->global_state = DSTATE_BUFPOST; | 
|  | } else if (cinfo->global_state != DSTATE_BUFPOST) { | 
|  | /* BUFPOST = repeat call after a suspension, anything else is error */ | 
|  | ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); | 
|  | } | 
|  | /* Read markers looking for SOS or EOI */ | 
|  | while (cinfo->input_scan_number <= cinfo->output_scan_number && | 
|  | ! cinfo->inputctl->eoi_reached) { | 
|  | if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED) | 
|  | return FALSE;		/* Suspend, come back later */ | 
|  | } | 
|  | cinfo->global_state = DSTATE_BUFIMAGE; | 
|  | return TRUE; | 
|  | } | 
|  |  | 
|  | #endif /* D_MULTISCAN_FILES_SUPPORTED */ | 
|  |  | 
|  | #endif //_FX_JPEG_TURBO_ |