diff options
author | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2015-11-06 07:14:47 +0100 |
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committer | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2015-11-06 07:14:47 +0100 |
commit | d479dd1aab1c1cb907932c6595b0ef33523fc797 (patch) | |
tree | ad7d454b9edaae3d8892d84cd8f8ef5c2697b79b /jpeg/jccoefct.c | |
parent | 9491825ddff7a294d1f49061bae7044e426aeb2e (diff) |
Imported Upstream version 1.8.3upstream/1.8.3
Diffstat (limited to 'jpeg/jccoefct.c')
-rwxr-xr-x | jpeg/jccoefct.c | 454 |
1 files changed, 0 insertions, 454 deletions
diff --git a/jpeg/jccoefct.c b/jpeg/jccoefct.c deleted file mode 100755 index 924a703..0000000 --- a/jpeg/jccoefct.c +++ /dev/null @@ -1,454 +0,0 @@ -/* - * jccoefct.c - * - * Copyright (C) 1994-1997, Thomas G. Lane. - * Modified 2003-2011 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 the coefficient buffer controller for compression. - * This controller is the top level of the JPEG compressor proper. - * The coefficient buffer lies between forward-DCT and entropy encoding steps. - */ - -#define JPEG_INTERNALS -#include "jinclude.h" -#include "jpeglib.h" - - -/* We use a full-image coefficient buffer when doing Huffman optimization, - * and also for writing multiple-scan JPEG files. In all cases, the DCT - * step is run during the first pass, and subsequent passes need only read - * the buffered coefficients. - */ -#ifdef ENTROPY_OPT_SUPPORTED -#define FULL_COEF_BUFFER_SUPPORTED -#else -#ifdef C_MULTISCAN_FILES_SUPPORTED -#define FULL_COEF_BUFFER_SUPPORTED -#endif -#endif - - -/* Private buffer controller object */ - -typedef struct { - struct jpeg_c_coef_controller pub; /* public fields */ - - JDIMENSION iMCU_row_num; /* iMCU row # within image */ - JDIMENSION mcu_ctr; /* counts MCUs processed in current row */ - int MCU_vert_offset; /* counts MCU rows within iMCU row */ - int MCU_rows_per_iMCU_row; /* number of such rows needed */ - - /* For single-pass compression, it's sufficient to buffer just one MCU - * (although this may prove a bit slow in practice). We allocate a - * workspace of C_MAX_BLOCKS_IN_MCU coefficient blocks, and reuse it for each - * MCU constructed and sent. (On 80x86, the workspace is FAR even though - * it's not really very big; this is to keep the module interfaces unchanged - * when a large coefficient buffer is necessary.) - * In multi-pass modes, this array points to the current MCU's blocks - * within the virtual arrays. - */ - JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU]; - - /* In multi-pass modes, we need a virtual block array for each component. */ - jvirt_barray_ptr whole_image[MAX_COMPONENTS]; -} my_coef_controller; - -typedef my_coef_controller * my_coef_ptr; - - -/* Forward declarations */ -METHODDEF(boolean) compress_data - JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); -#ifdef FULL_COEF_BUFFER_SUPPORTED -METHODDEF(boolean) compress_first_pass - JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); -METHODDEF(boolean) compress_output - JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); -#endif - - -LOCAL(void) -start_iMCU_row (j_compress_ptr cinfo) -/* Reset within-iMCU-row counters for a new row */ -{ - my_coef_ptr coef = (my_coef_ptr) cinfo->coef; - - /* In an interleaved scan, an MCU row is the same as an iMCU row. - * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows. - * But at the bottom of the image, process only what's left. - */ - if (cinfo->comps_in_scan > 1) { - coef->MCU_rows_per_iMCU_row = 1; - } else { - if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1)) - coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor; - else - coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height; - } - - coef->mcu_ctr = 0; - coef->MCU_vert_offset = 0; -} - - -/* - * Initialize for a processing pass. - */ - -METHODDEF(void) -start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode) -{ - my_coef_ptr coef = (my_coef_ptr) cinfo->coef; - - coef->iMCU_row_num = 0; - start_iMCU_row(cinfo); - - switch (pass_mode) { - case JBUF_PASS_THRU: - if (coef->whole_image[0] != NULL) - ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); - coef->pub.compress_data = compress_data; - break; -#ifdef FULL_COEF_BUFFER_SUPPORTED - case JBUF_SAVE_AND_PASS: - if (coef->whole_image[0] == NULL) - ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); - coef->pub.compress_data = compress_first_pass; - break; - case JBUF_CRANK_DEST: - if (coef->whole_image[0] == NULL) - ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); - coef->pub.compress_data = compress_output; - break; -#endif - default: - ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); - break; - } -} - - -/* - * Process some data in the single-pass case. - * We process the equivalent of one fully interleaved MCU row ("iMCU" row) - * per call, ie, v_samp_factor block rows for each component in the image. - * Returns TRUE if the iMCU row is completed, FALSE if suspended. - * - * NB: input_buf contains a plane for each component in image, - * which we index according to the component's SOF position. - */ - -METHODDEF(boolean) -compress_data (j_compress_ptr cinfo, JSAMPIMAGE input_buf) -{ - my_coef_ptr coef = (my_coef_ptr) cinfo->coef; - JDIMENSION MCU_col_num; /* index of current MCU within row */ - JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1; - JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; - int blkn, bi, ci, yindex, yoffset, blockcnt; - JDIMENSION ypos, xpos; - jpeg_component_info *compptr; - forward_DCT_ptr forward_DCT; - - /* Loop to write as much as one whole iMCU row */ - for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row; - yoffset++) { - for (MCU_col_num = coef->mcu_ctr; MCU_col_num <= last_MCU_col; - MCU_col_num++) { - /* Determine where data comes from in input_buf and do the DCT thing. - * Each call on forward_DCT processes a horizontal row of DCT blocks - * as wide as an MCU; we rely on having allocated the MCU_buffer[] blocks - * sequentially. Dummy blocks at the right or bottom edge are filled in - * specially. The data in them does not matter for image reconstruction, - * so we fill them with values that will encode to the smallest amount of - * data, viz: all zeroes in the AC entries, DC entries equal to previous - * block's DC value. (Thanks to Thomas Kinsman for this idea.) - */ - blkn = 0; - for (ci = 0; ci < cinfo->comps_in_scan; ci++) { - compptr = cinfo->cur_comp_info[ci]; - forward_DCT = cinfo->fdct->forward_DCT[compptr->component_index]; - blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width - : compptr->last_col_width; - xpos = MCU_col_num * compptr->MCU_sample_width; - ypos = yoffset * compptr->DCT_v_scaled_size; - /* ypos == (yoffset+yindex) * DCTSIZE */ - for (yindex = 0; yindex < compptr->MCU_height; yindex++) { - if (coef->iMCU_row_num < last_iMCU_row || - yoffset+yindex < compptr->last_row_height) { - (*forward_DCT) (cinfo, compptr, - input_buf[compptr->component_index], - coef->MCU_buffer[blkn], - ypos, xpos, (JDIMENSION) blockcnt); - if (blockcnt < compptr->MCU_width) { - /* Create some dummy blocks at the right edge of the image. */ - FMEMZERO((void FAR *) coef->MCU_buffer[blkn + blockcnt], - (compptr->MCU_width - blockcnt) * SIZEOF(JBLOCK)); - for (bi = blockcnt; bi < compptr->MCU_width; bi++) { - coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn+bi-1][0][0]; - } - } - } else { - /* Create a row of dummy blocks at the bottom of the image. */ - FMEMZERO((void FAR *) coef->MCU_buffer[blkn], - compptr->MCU_width * SIZEOF(JBLOCK)); - for (bi = 0; bi < compptr->MCU_width; bi++) { - coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn-1][0][0]; - } - } - blkn += compptr->MCU_width; - ypos += compptr->DCT_v_scaled_size; - } - } - /* Try to write the MCU. In event of a suspension failure, we will - * re-DCT the MCU on restart (a bit inefficient, could be fixed...) - */ - if (! (*cinfo->entropy->encode_mcu) (cinfo, coef->MCU_buffer)) { - /* Suspension forced; update state counters and exit */ - coef->MCU_vert_offset = yoffset; - coef->mcu_ctr = MCU_col_num; - return FALSE; - } - } - /* Completed an MCU row, but perhaps not an iMCU row */ - coef->mcu_ctr = 0; - } - /* Completed the iMCU row, advance counters for next one */ - coef->iMCU_row_num++; - start_iMCU_row(cinfo); - return TRUE; -} - - -#ifdef FULL_COEF_BUFFER_SUPPORTED - -/* - * Process some data in the first pass of a multi-pass case. - * We process the equivalent of one fully interleaved MCU row ("iMCU" row) - * per call, ie, v_samp_factor block rows for each component in the image. - * This amount of data is read from the source buffer, DCT'd and quantized, - * and saved into the virtual arrays. We also generate suitable dummy blocks - * as needed at the right and lower edges. (The dummy blocks are constructed - * in the virtual arrays, which have been padded appropriately.) This makes - * it possible for subsequent passes not to worry about real vs. dummy blocks. - * - * We must also emit the data to the entropy encoder. This is conveniently - * done by calling compress_output() after we've loaded the current strip - * of the virtual arrays. - * - * NB: input_buf contains a plane for each component in image. All - * components are DCT'd and loaded into the virtual arrays in this pass. - * However, it may be that only a subset of the components are emitted to - * the entropy encoder during this first pass; be careful about looking - * at the scan-dependent variables (MCU dimensions, etc). - */ - -METHODDEF(boolean) -compress_first_pass (j_compress_ptr cinfo, JSAMPIMAGE input_buf) -{ - my_coef_ptr coef = (my_coef_ptr) cinfo->coef; - JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; - JDIMENSION blocks_across, MCUs_across, MCUindex; - int bi, ci, h_samp_factor, block_row, block_rows, ndummy; - JCOEF lastDC; - jpeg_component_info *compptr; - JBLOCKARRAY buffer; - JBLOCKROW thisblockrow, lastblockrow; - forward_DCT_ptr forward_DCT; - - for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; - ci++, compptr++) { - /* Align the virtual buffer for this component. */ - buffer = (*cinfo->mem->access_virt_barray) - ((j_common_ptr) cinfo, coef->whole_image[ci], - coef->iMCU_row_num * compptr->v_samp_factor, - (JDIMENSION) compptr->v_samp_factor, TRUE); - /* Count non-dummy DCT block rows in this iMCU row. */ - if (coef->iMCU_row_num < last_iMCU_row) - block_rows = compptr->v_samp_factor; - else { - /* NB: can't use last_row_height here, since may not be set! */ - block_rows = (int) (compptr->height_in_blocks % compptr->v_samp_factor); - if (block_rows == 0) block_rows = compptr->v_samp_factor; - } - blocks_across = compptr->width_in_blocks; - h_samp_factor = compptr->h_samp_factor; - /* Count number of dummy blocks to be added at the right margin. */ - ndummy = (int) (blocks_across % h_samp_factor); - if (ndummy > 0) - ndummy = h_samp_factor - ndummy; - forward_DCT = cinfo->fdct->forward_DCT[ci]; - /* Perform DCT for all non-dummy blocks in this iMCU row. Each call - * on forward_DCT processes a complete horizontal row of DCT blocks. - */ - for (block_row = 0; block_row < block_rows; block_row++) { - thisblockrow = buffer[block_row]; - (*forward_DCT) (cinfo, compptr, input_buf[ci], thisblockrow, - (JDIMENSION) (block_row * compptr->DCT_v_scaled_size), - (JDIMENSION) 0, blocks_across); - if (ndummy > 0) { - /* Create dummy blocks at the right edge of the image. */ - thisblockrow += blocks_across; /* => first dummy block */ - FMEMZERO((void FAR *) thisblockrow, ndummy * SIZEOF(JBLOCK)); - lastDC = thisblockrow[-1][0]; - for (bi = 0; bi < ndummy; bi++) { - thisblockrow[bi][0] = lastDC; - } - } - } - /* If at end of image, create dummy block rows as needed. - * The tricky part here is that within each MCU, we want the DC values - * of the dummy blocks to match the last real block's DC value. - * This squeezes a few more bytes out of the resulting file... - */ - if (coef->iMCU_row_num == last_iMCU_row) { - blocks_across += ndummy; /* include lower right corner */ - MCUs_across = blocks_across / h_samp_factor; - for (block_row = block_rows; block_row < compptr->v_samp_factor; - block_row++) { - thisblockrow = buffer[block_row]; - lastblockrow = buffer[block_row-1]; - FMEMZERO((void FAR *) thisblockrow, - (size_t) (blocks_across * SIZEOF(JBLOCK))); - for (MCUindex = 0; MCUindex < MCUs_across; MCUindex++) { - lastDC = lastblockrow[h_samp_factor-1][0]; - for (bi = 0; bi < h_samp_factor; bi++) { - thisblockrow[bi][0] = lastDC; - } - thisblockrow += h_samp_factor; /* advance to next MCU in row */ - lastblockrow += h_samp_factor; - } - } - } - } - /* NB: compress_output will increment iMCU_row_num if successful. - * A suspension return will result in redoing all the work above next time. - */ - - /* Emit data to the entropy encoder, sharing code with subsequent passes */ - return compress_output(cinfo, input_buf); -} - - -/* - * Process some data in subsequent passes of a multi-pass case. - * We process the equivalent of one fully interleaved MCU row ("iMCU" row) - * per call, ie, v_samp_factor block rows for each component in the scan. - * The data is obtained from the virtual arrays and fed to the entropy coder. - * Returns TRUE if the iMCU row is completed, FALSE if suspended. - * - * NB: input_buf is ignored; it is likely to be a NULL pointer. - */ - -METHODDEF(boolean) -compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf) -{ - my_coef_ptr coef = (my_coef_ptr) cinfo->coef; - JDIMENSION MCU_col_num; /* index of current MCU within row */ - int blkn, ci, xindex, yindex, yoffset; - JDIMENSION start_col; - JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN]; - JBLOCKROW buffer_ptr; - jpeg_component_info *compptr; - - /* Align the virtual buffers for the components used in this scan. - * NB: during first pass, this is safe only because the buffers will - * already be aligned properly, so jmemmgr.c won't need to do any I/O. - */ - for (ci = 0; ci < cinfo->comps_in_scan; ci++) { - compptr = cinfo->cur_comp_info[ci]; - buffer[ci] = (*cinfo->mem->access_virt_barray) - ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index], - coef->iMCU_row_num * compptr->v_samp_factor, - (JDIMENSION) compptr->v_samp_factor, FALSE); - } - - /* Loop to process one whole iMCU row */ - for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row; - yoffset++) { - for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row; - MCU_col_num++) { - /* Construct list of pointers to DCT blocks belonging to this MCU */ - blkn = 0; /* index of current DCT block within MCU */ - for (ci = 0; ci < cinfo->comps_in_scan; ci++) { - compptr = cinfo->cur_comp_info[ci]; - start_col = MCU_col_num * compptr->MCU_width; - for (yindex = 0; yindex < compptr->MCU_height; yindex++) { - buffer_ptr = buffer[ci][yindex+yoffset] + start_col; - for (xindex = 0; xindex < compptr->MCU_width; xindex++) { - coef->MCU_buffer[blkn++] = buffer_ptr++; - } - } - } - /* Try to write the MCU. */ - if (! (*cinfo->entropy->encode_mcu) (cinfo, coef->MCU_buffer)) { - /* Suspension forced; update state counters and exit */ - coef->MCU_vert_offset = yoffset; - coef->mcu_ctr = MCU_col_num; - return FALSE; - } - } - /* Completed an MCU row, but perhaps not an iMCU row */ - coef->mcu_ctr = 0; - } - /* Completed the iMCU row, advance counters for next one */ - coef->iMCU_row_num++; - start_iMCU_row(cinfo); - return TRUE; -} - -#endif /* FULL_COEF_BUFFER_SUPPORTED */ - - -/* - * Initialize coefficient buffer controller. - */ - -GLOBAL(void) -jinit_c_coef_controller (j_compress_ptr cinfo, boolean need_full_buffer) -{ - my_coef_ptr coef; - - coef = (my_coef_ptr) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - SIZEOF(my_coef_controller)); - cinfo->coef = (struct jpeg_c_coef_controller *) coef; - coef->pub.start_pass = start_pass_coef; - - /* Create the coefficient buffer. */ - if (need_full_buffer) { -#ifdef FULL_COEF_BUFFER_SUPPORTED - /* Allocate a full-image virtual array for each component, */ - /* padded to a multiple of samp_factor DCT blocks in each direction. */ - int ci; - jpeg_component_info *compptr; - - for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; - ci++, compptr++) { - coef->whole_image[ci] = (*cinfo->mem->request_virt_barray) - ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, - (JDIMENSION) jround_up((long) compptr->width_in_blocks, - (long) compptr->h_samp_factor), - (JDIMENSION) jround_up((long) compptr->height_in_blocks, - (long) compptr->v_samp_factor), - (JDIMENSION) compptr->v_samp_factor); - } -#else - ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); -#endif - } else { - /* We only need a single-MCU buffer. */ - JBLOCKROW buffer; - int i; - - buffer = (JBLOCKROW) - (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, - C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK)); - for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) { - coef->MCU_buffer[i] = buffer + i; - } - coef->whole_image[0] = NULL; /* flag for no virtual arrays */ - } -} |