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- /*
- * jdapistd.c
- *
- * This file was part of the Independent JPEG Group's software:
- * Copyright (C) 1994-1996, Thomas G. Lane.
- * libjpeg-turbo Modifications:
- * Copyright (C) 2010, 2015-2016, D. R. Commander.
- * Copyright (C) 2015, Google, Inc.
- * For conditions of distribution and use, see the accompanying README.ijg
- * 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.
- */
- #include "jinclude.h"
- #include "jdmainct.h"
- #include "jdcoefct.h"
- #include "jdsample.h"
- #include "jmemsys.h"
- /* Forward declarations */
- LOCAL(boolean) output_pass_setup (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;
- }
- /*
- * Enable partial scanline decompression
- *
- * Must be called after jpeg_start_decompress() and before any calls to
- * jpeg_read_scanlines() or jpeg_skip_scanlines().
- *
- * Refer to libjpeg.txt for more information.
- */
- GLOBAL(void)
- jpeg_crop_scanline (j_decompress_ptr cinfo, JDIMENSION *xoffset,
- JDIMENSION *width)
- {
- int ci, align, orig_downsampled_width;
- JDIMENSION input_xoffset;
- boolean reinit_upsampler = FALSE;
- jpeg_component_info *compptr;
- if (cinfo->global_state != DSTATE_SCANNING || cinfo->output_scanline != 0)
- ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
- if (!xoffset || !width)
- ERREXIT(cinfo, JERR_BAD_CROP_SPEC);
- /* xoffset and width must fall within the output image dimensions. */
- if (*width == 0 || *xoffset + *width > cinfo->output_width)
- ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
- /* No need to do anything if the caller wants the entire width. */
- if (*width == cinfo->output_width)
- return;
- /* Ensuring the proper alignment of xoffset is tricky. At minimum, it
- * must align with an MCU boundary, because:
- *
- * (1) The IDCT is performed in blocks, and it is not feasible to modify
- * the algorithm so that it can transform partial blocks.
- * (2) Because of the SIMD extensions, any input buffer passed to the
- * upsampling and color conversion routines must be aligned to the
- * SIMD word size (for instance, 128-bit in the case of SSE2.) The
- * easiest way to accomplish this without copying data is to ensure
- * that upsampling and color conversion begin at the start of the
- * first MCU column that will be inverse transformed.
- *
- * In practice, we actually impose a stricter alignment requirement. We
- * require that xoffset be a multiple of the maximum MCU column width of all
- * of the components (the "iMCU column width.") This is to simplify the
- * single-pass decompression case, allowing us to use the same MCU column
- * width for all of the components.
- */
- align = cinfo->_min_DCT_scaled_size * cinfo->max_h_samp_factor;
- /* Adjust xoffset to the nearest iMCU boundary <= the requested value */
- input_xoffset = *xoffset;
- *xoffset = (input_xoffset / align) * align;
- /* Adjust the width so that the right edge of the output image is as
- * requested (only the left edge is altered.) It is important that calling
- * programs check this value after this function returns, so that they can
- * allocate an output buffer with the appropriate size.
- */
- *width = *width + input_xoffset - *xoffset;
- cinfo->output_width = *width;
- /* Set the first and last iMCU columns that we must decompress. These values
- * will be used in single-scan decompressions.
- */
- cinfo->master->first_iMCU_col =
- (JDIMENSION) (long) (*xoffset) / (long) align;
- cinfo->master->last_iMCU_col =
- (JDIMENSION) jdiv_round_up((long) (*xoffset + cinfo->output_width),
- (long) align) - 1;
- for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
- ci++, compptr++) {
- /* Set downsampled_width to the new output width. */
- orig_downsampled_width = compptr->downsampled_width;
- compptr->downsampled_width =
- (JDIMENSION) jdiv_round_up((long) (cinfo->output_width *
- compptr->h_samp_factor),
- (long) cinfo->max_h_samp_factor);
- if (compptr->downsampled_width < 2 && orig_downsampled_width >= 2)
- reinit_upsampler = TRUE;
- /* Set the first and last iMCU columns that we must decompress. These
- * values will be used in multi-scan decompressions.
- */
- cinfo->master->first_MCU_col[ci] =
- (JDIMENSION) (long) (*xoffset * compptr->h_samp_factor) /
- (long) align;
- cinfo->master->last_MCU_col[ci] =
- (JDIMENSION) jdiv_round_up((long) ((*xoffset + cinfo->output_width) *
- compptr->h_samp_factor),
- (long) align) - 1;
- }
- if (reinit_upsampler) {
- cinfo->master->jinit_upsampler_no_alloc = TRUE;
- jinit_upsampler(cinfo);
- cinfo->master->jinit_upsampler_no_alloc = FALSE;
- }
- }
- /*
- * 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)
- 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;
- }
- /* Dummy color convert function used by jpeg_skip_scanlines() */
- LOCAL(void)
- noop_convert (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
- JDIMENSION input_row, JSAMPARRAY output_buf, int num_rows)
- {
- }
- /*
- * In some cases, it is best to call jpeg_read_scanlines() and discard the
- * output, rather than skipping the scanlines, because this allows us to
- * maintain the internal state of the context-based upsampler. In these cases,
- * we set up and tear down a dummy color converter in order to avoid valgrind
- * errors and to achieve the best possible performance.
- */
- LOCAL(void)
- read_and_discard_scanlines (j_decompress_ptr cinfo, JDIMENSION num_lines)
- {
- JDIMENSION n;
- void (*color_convert) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
- JDIMENSION input_row, JSAMPARRAY output_buf,
- int num_rows);
- color_convert = cinfo->cconvert->color_convert;
- cinfo->cconvert->color_convert = noop_convert;
- for (n = 0; n < num_lines; n++)
- jpeg_read_scanlines(cinfo, NULL, 1);
- cinfo->cconvert->color_convert = color_convert;
- }
- /*
- * Called by jpeg_skip_scanlines(). This partially skips a decompress block by
- * incrementing the rowgroup counter.
- */
- LOCAL(void)
- increment_simple_rowgroup_ctr (j_decompress_ptr cinfo, JDIMENSION rows)
- {
- JDIMENSION rows_left;
- my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
- /* Increment the counter to the next row group after the skipped rows. */
- main_ptr->rowgroup_ctr += rows / cinfo->max_v_samp_factor;
- /* Partially skipping a row group would involve modifying the internal state
- * of the upsampler, so read the remaining rows into a dummy buffer instead.
- */
- rows_left = rows % cinfo->max_v_samp_factor;
- cinfo->output_scanline += rows - rows_left;
- read_and_discard_scanlines(cinfo, rows_left);
- }
- /*
- * Skips some scanlines of data from the JPEG decompressor.
- *
- * The return value will be the number of lines actually skipped. If skipping
- * num_lines would move beyond the end of the image, then the actual number of
- * lines remaining in the image is returned. Otherwise, the return value will
- * be equal to num_lines.
- *
- * Refer to libjpeg.txt for more information.
- */
- GLOBAL(JDIMENSION)
- jpeg_skip_scanlines (j_decompress_ptr cinfo, JDIMENSION num_lines)
- {
- my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
- my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
- my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
- JDIMENSION i, x;
- int y;
- JDIMENSION lines_per_iMCU_row, lines_left_in_iMCU_row, lines_after_iMCU_row;
- JDIMENSION lines_to_skip, lines_to_read;
- if (cinfo->global_state != DSTATE_SCANNING)
- ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
- /* Do not skip past the bottom of the image. */
- if (cinfo->output_scanline + num_lines >= cinfo->output_height) {
- cinfo->output_scanline = cinfo->output_height;
- return cinfo->output_height - cinfo->output_scanline;
- }
- if (num_lines == 0)
- return 0;
- lines_per_iMCU_row = cinfo->_min_DCT_scaled_size * cinfo->max_v_samp_factor;
- lines_left_in_iMCU_row =
- (lines_per_iMCU_row - (cinfo->output_scanline % lines_per_iMCU_row)) %
- lines_per_iMCU_row;
- lines_after_iMCU_row = num_lines - lines_left_in_iMCU_row;
- /* Skip the lines remaining in the current iMCU row. When upsampling
- * requires context rows, we need the previous and next rows in order to read
- * the current row. This adds some complexity.
- */
- if (cinfo->upsample->need_context_rows) {
- /* If the skipped lines would not move us past the current iMCU row, we
- * read the lines and ignore them. There might be a faster way of doing
- * this, but we are facing increasing complexity for diminishing returns.
- * The increasing complexity would be a by-product of meddling with the
- * state machine used to skip context rows. Near the end of an iMCU row,
- * the next iMCU row may have already been entropy-decoded. In this unique
- * case, we will read the next iMCU row if we cannot skip past it as well.
- */
- if ((num_lines < lines_left_in_iMCU_row + 1) ||
- (lines_left_in_iMCU_row <= 1 && main_ptr->buffer_full &&
- lines_after_iMCU_row < lines_per_iMCU_row + 1)) {
- read_and_discard_scanlines(cinfo, num_lines);
- return num_lines;
- }
- /* If the next iMCU row has already been entropy-decoded, make sure that
- * we do not skip too far.
- */
- if (lines_left_in_iMCU_row <= 1 && main_ptr->buffer_full) {
- cinfo->output_scanline += lines_left_in_iMCU_row + lines_per_iMCU_row;
- lines_after_iMCU_row -= lines_per_iMCU_row;
- } else {
- cinfo->output_scanline += lines_left_in_iMCU_row;
- }
- /* If we have just completed the first block, adjust the buffer pointers */
- if (main_ptr->iMCU_row_ctr == 0 ||
- (main_ptr->iMCU_row_ctr == 1 && lines_left_in_iMCU_row > 2))
- set_wraparound_pointers(cinfo);
- main_ptr->buffer_full = FALSE;
- main_ptr->rowgroup_ctr = 0;
- main_ptr->context_state = CTX_PREPARE_FOR_IMCU;
- upsample->next_row_out = cinfo->max_v_samp_factor;
- upsample->rows_to_go = cinfo->output_height - cinfo->output_scanline;
- }
- /* Skipping is much simpler when context rows are not required. */
- else {
- if (num_lines < lines_left_in_iMCU_row) {
- increment_simple_rowgroup_ctr(cinfo, num_lines);
- return num_lines;
- } else {
- cinfo->output_scanline += lines_left_in_iMCU_row;
- main_ptr->buffer_full = FALSE;
- main_ptr->rowgroup_ctr = 0;
- upsample->next_row_out = cinfo->max_v_samp_factor;
- upsample->rows_to_go = cinfo->output_height - cinfo->output_scanline;
- }
- }
- /* Calculate how many full iMCU rows we can skip. */
- if (cinfo->upsample->need_context_rows)
- lines_to_skip = ((lines_after_iMCU_row - 1) / lines_per_iMCU_row) *
- lines_per_iMCU_row;
- else
- lines_to_skip = (lines_after_iMCU_row / lines_per_iMCU_row) *
- lines_per_iMCU_row;
- /* Calculate the number of lines that remain to be skipped after skipping all
- * of the full iMCU rows that we can. We will not read these lines unless we
- * have to.
- */
- lines_to_read = lines_after_iMCU_row - lines_to_skip;
- /* For images requiring multiple scans (progressive, non-interleaved, etc.),
- * all of the entropy decoding occurs in jpeg_start_decompress(), assuming
- * that the input data source is non-suspending. This makes skipping easy.
- */
- if (cinfo->inputctl->has_multiple_scans) {
- if (cinfo->upsample->need_context_rows) {
- cinfo->output_scanline += lines_to_skip;
- cinfo->output_iMCU_row += lines_to_skip / lines_per_iMCU_row;
- main_ptr->iMCU_row_ctr += lines_after_iMCU_row / lines_per_iMCU_row;
- /* It is complex to properly move to the middle of a context block, so
- * read the remaining lines instead of skipping them.
- */
- read_and_discard_scanlines(cinfo, lines_to_read);
- } else {
- cinfo->output_scanline += lines_to_skip;
- cinfo->output_iMCU_row += lines_to_skip / lines_per_iMCU_row;
- increment_simple_rowgroup_ctr(cinfo, lines_to_read);
- }
- upsample->rows_to_go = cinfo->output_height - cinfo->output_scanline;
- return num_lines;
- }
- /* Skip the iMCU rows that we can safely skip. */
- for (i = 0; i < lines_to_skip; i += lines_per_iMCU_row) {
- for (y = 0; y < coef->MCU_rows_per_iMCU_row; y++) {
- for (x = 0; x < cinfo->MCUs_per_row; x++) {
- /* Calling decode_mcu() with a NULL pointer causes it to discard the
- * decoded coefficients. This is ~5% faster for large subsets, but
- * it's tough to tell a difference for smaller images.
- */
- (*cinfo->entropy->decode_mcu) (cinfo, NULL);
- }
- }
- cinfo->input_iMCU_row++;
- cinfo->output_iMCU_row++;
- if (cinfo->input_iMCU_row < cinfo->total_iMCU_rows)
- start_iMCU_row(cinfo);
- else
- (*cinfo->inputctl->finish_input_pass) (cinfo);
- }
- cinfo->output_scanline += lines_to_skip;
- if (cinfo->upsample->need_context_rows) {
- /* Context-based upsampling keeps track of iMCU rows. */
- main_ptr->iMCU_row_ctr += lines_to_skip / lines_per_iMCU_row;
- /* It is complex to properly move to the middle of a context block, so
- * read the remaining lines instead of skipping them.
- */
- read_and_discard_scanlines(cinfo, lines_to_read);
- } else {
- increment_simple_rowgroup_ctr(cinfo, lines_to_read);
- }
- /* Since skipping lines involves skipping the upsampling step, the value of
- * "rows_to_go" will become invalid unless we set it here. NOTE: This is a
- * bit odd, since "rows_to_go" seems to be redundantly keeping track of
- * output_scanline.
- */
- upsample->rows_to_go = cinfo->output_height - cinfo->output_scanline;
- /* Always skip the requested number of lines. */
- return num_lines;
- }
- /*
- * 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 */
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