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diff --git a/jpg/jctrans.c b/jpg/jctrans.c
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+/*
+ * jctrans.c
+ *
+ * Copyright (C) 1995-1998, Thomas G. Lane.
+ * Modified 2000-2011 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 library routines for transcoding compression,
+ * that is, writing raw DCT coefficient arrays to an output JPEG file.
+ * The routines in jcapimin.c will also be needed by a transcoder.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+
+
+/* Forward declarations */
+LOCAL(void) transencode_master_selection
+ JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));
+LOCAL(void) transencode_coef_controller
+ JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));
+
+
+/*
+ * Compression initialization for writing raw-coefficient data.
+ * Before calling this, all parameters and a data destination must be set up.
+ * Call jpeg_finish_compress() to actually write the data.
+ *
+ * The number of passed virtual arrays must match cinfo->num_components.
+ * Note that the virtual arrays need not be filled or even realized at
+ * the time write_coefficients is called; indeed, if the virtual arrays
+ * were requested from this compression object's memory manager, they
+ * typically will be realized during this routine and filled afterwards.
+ */
+
+GLOBAL(void)
+jpeg_write_coefficients (j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)
+{
+ if (cinfo->global_state != CSTATE_START)
+ ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
+ /* Mark all tables to be written */
+ jpeg_suppress_tables(cinfo, FALSE);
+ /* (Re)initialize error mgr and destination modules */
+ (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
+ (*cinfo->dest->init_destination) (cinfo);
+ /* Perform master selection of active modules */
+ transencode_master_selection(cinfo, coef_arrays);
+ /* Wait for jpeg_finish_compress() call */
+ cinfo->next_scanline = 0; /* so jpeg_write_marker works */
+ cinfo->global_state = CSTATE_WRCOEFS;
+}
+
+
+/*
+ * Initialize the compression object with default parameters,
+ * then copy from the source object all parameters needed for lossless
+ * transcoding. Parameters that can be varied without loss (such as
+ * scan script and Huffman optimization) are left in their default states.
+ */
+
+GLOBAL(void)
+jpeg_copy_critical_parameters (j_decompress_ptr srcinfo,
+ j_compress_ptr dstinfo)
+{
+ JQUANT_TBL ** qtblptr;
+ jpeg_component_info *incomp, *outcomp;
+ JQUANT_TBL *c_quant, *slot_quant;
+ int tblno, ci, coefi;
+
+ /* Safety check to ensure start_compress not called yet. */
+ if (dstinfo->global_state != CSTATE_START)
+ ERREXIT1(dstinfo, JERR_BAD_STATE, dstinfo->global_state);
+ /* Copy fundamental image dimensions */
+ dstinfo->image_width = srcinfo->image_width;
+ dstinfo->image_height = srcinfo->image_height;
+ dstinfo->input_components = srcinfo->num_components;
+ dstinfo->in_color_space = srcinfo->jpeg_color_space;
+ dstinfo->jpeg_width = srcinfo->output_width;
+ dstinfo->jpeg_height = srcinfo->output_height;
+ dstinfo->min_DCT_h_scaled_size = srcinfo->min_DCT_h_scaled_size;
+ dstinfo->min_DCT_v_scaled_size = srcinfo->min_DCT_v_scaled_size;
+ /* Initialize all parameters to default values */
+ jpeg_set_defaults(dstinfo);
+ /* jpeg_set_defaults may choose wrong colorspace, eg YCbCr if input is RGB.
+ * Fix it to get the right header markers for the image colorspace.
+ */
+ jpeg_set_colorspace(dstinfo, srcinfo->jpeg_color_space);
+ dstinfo->data_precision = srcinfo->data_precision;
+ dstinfo->CCIR601_sampling = srcinfo->CCIR601_sampling;
+ /* Copy the source's quantization tables. */
+ for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
+ if (srcinfo->quant_tbl_ptrs[tblno] != NULL) {
+ qtblptr = & dstinfo->quant_tbl_ptrs[tblno];
+ if (*qtblptr == NULL)
+ *qtblptr = jpeg_alloc_quant_table((j_common_ptr) dstinfo);
+ MEMCOPY((*qtblptr)->quantval,
+ srcinfo->quant_tbl_ptrs[tblno]->quantval,
+ SIZEOF((*qtblptr)->quantval));
+ (*qtblptr)->sent_table = FALSE;
+ }
+ }
+ /* Copy the source's per-component info.
+ * Note we assume jpeg_set_defaults has allocated the dest comp_info array.
+ */
+ dstinfo->num_components = srcinfo->num_components;
+ if (dstinfo->num_components < 1 || dstinfo->num_components > MAX_COMPONENTS)
+ ERREXIT2(dstinfo, JERR_COMPONENT_COUNT, dstinfo->num_components,
+ MAX_COMPONENTS);
+ for (ci = 0, incomp = srcinfo->comp_info, outcomp = dstinfo->comp_info;
+ ci < dstinfo->num_components; ci++, incomp++, outcomp++) {
+ outcomp->component_id = incomp->component_id;
+ outcomp->h_samp_factor = incomp->h_samp_factor;
+ outcomp->v_samp_factor = incomp->v_samp_factor;
+ outcomp->quant_tbl_no = incomp->quant_tbl_no;
+ /* Make sure saved quantization table for component matches the qtable
+ * slot. If not, the input file re-used this qtable slot.
+ * IJG encoder currently cannot duplicate this.
+ */
+ tblno = outcomp->quant_tbl_no;
+ if (tblno < 0 || tblno >= NUM_QUANT_TBLS ||
+ srcinfo->quant_tbl_ptrs[tblno] == NULL)
+ ERREXIT1(dstinfo, JERR_NO_QUANT_TABLE, tblno);
+ slot_quant = srcinfo->quant_tbl_ptrs[tblno];
+ c_quant = incomp->quant_table;
+ if (c_quant != NULL) {
+ for (coefi = 0; coefi < DCTSIZE2; coefi++) {
+ if (c_quant->quantval[coefi] != slot_quant->quantval[coefi])
+ ERREXIT1(dstinfo, JERR_MISMATCHED_QUANT_TABLE, tblno);
+ }
+ }
+ /* Note: we do not copy the source's Huffman table assignments;
+ * instead we rely on jpeg_set_colorspace to have made a suitable choice.
+ */
+ }
+ /* Also copy JFIF version and resolution information, if available.
+ * Strictly speaking this isn't "critical" info, but it's nearly
+ * always appropriate to copy it if available. In particular,
+ * if the application chooses to copy JFIF 1.02 extension markers from
+ * the source file, we need to copy the version to make sure we don't
+ * emit a file that has 1.02 extensions but a claimed version of 1.01.
+ * We will *not*, however, copy version info from mislabeled "2.01" files.
+ */
+ if (srcinfo->saw_JFIF_marker) {
+ if (srcinfo->JFIF_major_version == 1) {
+ dstinfo->JFIF_major_version = srcinfo->JFIF_major_version;
+ dstinfo->JFIF_minor_version = srcinfo->JFIF_minor_version;
+ }
+ dstinfo->density_unit = srcinfo->density_unit;
+ dstinfo->X_density = srcinfo->X_density;
+ dstinfo->Y_density = srcinfo->Y_density;
+ }
+}
+
+
+/*
+ * Master selection of compression modules for transcoding.
+ * This substitutes for jcinit.c's initialization of the full compressor.
+ */
+
+LOCAL(void)
+transencode_master_selection (j_compress_ptr cinfo,
+ jvirt_barray_ptr * coef_arrays)
+{
+ /* Initialize master control (includes parameter checking/processing) */
+ jinit_c_master_control(cinfo, TRUE /* transcode only */);
+
+ /* Entropy encoding: either Huffman or arithmetic coding. */
+ if (cinfo->arith_code)
+ jinit_arith_encoder(cinfo);
+ else {
+ jinit_huff_encoder(cinfo);
+ }
+
+ /* We need a special coefficient buffer controller. */
+ transencode_coef_controller(cinfo, coef_arrays);
+
+ jinit_marker_writer(cinfo);
+
+ /* We can now tell the memory manager to allocate virtual arrays. */
+ (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
+
+ /* Write the datastream header (SOI, JFIF) immediately.
+ * Frame and scan headers are postponed till later.
+ * This lets application insert special markers after the SOI.
+ */
+ (*cinfo->marker->write_file_header) (cinfo);
+}
+
+
+/*
+ * The rest of this file is a special implementation of the coefficient
+ * buffer controller. This is similar to jccoefct.c, but it handles only
+ * output from presupplied virtual arrays. Furthermore, we generate any
+ * dummy padding blocks on-the-fly rather than expecting them to be present
+ * in the arrays.
+ */
+
+/* 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 */
+
+ /* Virtual block array for each component. */
+ jvirt_barray_ptr * whole_image;
+
+ /* Workspace for constructing dummy blocks at right/bottom edges. */
+ JBLOCKROW dummy_buffer[C_MAX_BLOCKS_IN_MCU];
+} my_coef_controller;
+
+typedef my_coef_controller * my_coef_ptr;
+
+
+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;
+
+ if (pass_mode != JBUF_CRANK_DEST)
+ ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
+
+ coef->iMCU_row_num = 0;
+ start_iMCU_row(cinfo);
+}
+
+
+/*
+ * Process some data.
+ * 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 */
+ JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;
+ JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
+ int blkn, ci, xindex, yindex, yoffset, blockcnt;
+ JDIMENSION start_col;
+ JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN];
+ JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU];
+ JBLOCKROW buffer_ptr;
+ jpeg_component_info *compptr;
+
+ /* Align the virtual buffers for the components used in this scan. */
+ 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;
+ blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width
+ : compptr->last_col_width;
+ for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
+ if (coef->iMCU_row_num < last_iMCU_row ||
+ yindex+yoffset < compptr->last_row_height) {
+ /* Fill in pointers to real blocks in this row */
+ buffer_ptr = buffer[ci][yindex+yoffset] + start_col;
+ for (xindex = 0; xindex < blockcnt; xindex++)
+ MCU_buffer[blkn++] = buffer_ptr++;
+ } else {
+ /* At bottom of image, need a whole row of dummy blocks */
+ xindex = 0;
+ }
+ /* Fill in any dummy blocks needed in this row.
+ * Dummy blocks are filled in the same way as in jccoefct.c:
+ * all zeroes in the AC entries, DC entries equal to previous
+ * block's DC value. The init routine has already zeroed the
+ * AC entries, so we need only set the DC entries correctly.
+ */
+ for (; xindex < compptr->MCU_width; xindex++) {
+ MCU_buffer[blkn] = coef->dummy_buffer[blkn];
+ MCU_buffer[blkn][0][0] = MCU_buffer[blkn-1][0][0];
+ blkn++;
+ }
+ }
+ }
+ /* Try to write the MCU. */
+ if (! (*cinfo->entropy->encode_mcu) (cinfo, 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;
+}
+
+
+/*
+ * Initialize coefficient buffer controller.
+ *
+ * Each passed coefficient array must be the right size for that
+ * coefficient: width_in_blocks wide and height_in_blocks high,
+ * with unitheight at least v_samp_factor.
+ */
+
+LOCAL(void)
+transencode_coef_controller (j_compress_ptr cinfo,
+ jvirt_barray_ptr * coef_arrays)
+{
+ my_coef_ptr coef;
+ JBLOCKROW buffer;
+ int i;
+
+ 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;
+ coef->pub.compress_data = compress_output;
+
+ /* Save pointer to virtual arrays */
+ coef->whole_image = coef_arrays;
+
+ /* Allocate and pre-zero space for dummy DCT blocks. */
+ buffer = (JBLOCKROW)
+ (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+ C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
+ FMEMZERO((void FAR *) buffer, C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
+ for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) {
+ coef->dummy_buffer[i] = buffer + i;
+ }
+}