jpeg_init_read_tile_scanline(j_decompress_ptr cinfo, huffman_index *index,
int *start_x, int *start_y, int *width, int *height)
{
int lines_per_iMCU_row = cinfo->max_v_samp_factor * DCTSIZE;
int lines_per_iMCU_col = cinfo->max_h_samp_factor * DCTSIZE;
int row_offset = *start_y / lines_per_iMCU_row;
int col_left_boundary = ((*start_x / lines_per_iMCU_col)
/ index->MCU_sample_size) * index->MCU_sample_size;
int col_right_boundary =
jdiv_round_up(*start_x + *width, lines_per_iMCU_col);
cinfo->coef->MCU_columns_to_skip =
*start_x / lines_per_iMCU_col - col_left_boundary;
*height = (*start_y - row_offset * lines_per_iMCU_row) + *height;
*start_x = col_left_boundary * lines_per_iMCU_col;
*start_y = row_offset * lines_per_iMCU_row;
cinfo->image_width = jmin(cinfo->original_image_width,
col_right_boundary * lines_per_iMCU_col) -
col_left_boundary * lines_per_iMCU_col;
cinfo->input_iMCU_row = row_offset;
cinfo->output_iMCU_row = row_offset;
jinit_color_deconverter(cinfo);
jpeg_calc_output_dimensions(cinfo);
jinit_upsampler(cinfo);
(*cinfo->master->prepare_for_output_pass) (cinfo);
if (cinfo->progressive_mode)
(*cinfo->entropy->start_pass) (cinfo);
else
jpeg_decompress_per_scan_setup(cinfo);
int sample_size = DCTSIZE / cinfo->min_DCT_scaled_size;
*height = jdiv_round_up(*height, sample_size);
*width = cinfo->output_width;
cinfo->output_scanline = lines_per_iMCU_row * row_offset / sample_size;
cinfo->inputctl->consume_input = cinfo->coef->consume_data;
cinfo->inputctl->consume_input_build_huffman_index =
cinfo->coef->consume_data_build_huffman_index;
cinfo->entropy->index = index;
cinfo->input_iMCU_row = row_offset;
cinfo->output_iMCU_row = row_offset;
cinfo->coef->MCU_column_left_boundary = col_left_boundary;
cinfo->coef->MCU_column_right_boundary = col_right_boundary;
cinfo->coef->column_left_boundary =
col_left_boundary / index->MCU_sample_size;
cinfo->coef->column_right_boundary =
jdiv_round_up(col_right_boundary, index->MCU_sample_size);
}
consume_data_build_huffman_index_baseline(j_decompress_ptr cinfo,
huffman_index *index, int current_scan) {
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
JDIMENSION MCU_col_num; /* index of current MCU within row */
int ci, xindex, yindex, yoffset;
JDIMENSION start_col;
JBLOCKROW buffer_ptr;
huffman_scan_header *scan_header = index->scan + current_scan;
scan_header->MCU_rows_per_iMCU_row = coef->MCU_rows_per_iMCU_row;
size_t allocate_size = coef->MCU_rows_per_iMCU_row
* jdiv_round_up(cinfo->MCUs_per_row, index->MCU_sample_size)
* sizeof(huffman_offset_data);
scan_header->offset[cinfo->input_iMCU_row] =
(huffman_offset_data *) malloc(allocate_size);
index->mem_used += allocate_size;
huffman_offset_data *offset_data = scan_header->offset[cinfo->input_iMCU_row];
/* 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++) {
// Record huffman bit offset
if (MCU_col_num % index->MCU_sample_size == 0) {
(*cinfo->entropy->get_huffman_decoder_configuration)
(cinfo, offset_data);
++offset_data;
}
/* Try to fetch the MCU. */
if (!(*cinfo->entropy->decode_mcu_discard_coef)(cinfo)) {
/* Suspension forced; update state counters and exit */
coef->MCU_vert_offset = yoffset;
coef->MCU_ctr = MCU_col_num;
return JPEG_SUSPENDED;
}
}
/* Completed an MCU row, but perhaps not an iMCU row */
coef->MCU_ctr = 0;
}
/* Completed the iMCU row, advance counters for next one */
if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) {
start_iMCU_row(cinfo);
return JPEG_ROW_COMPLETED;
}
/* Completed the scan */
(*cinfo->inputctl->finish_input_pass)(cinfo);
return JPEG_SCAN_COMPLETED;
}
initial_setup (j_compress_ptr cinfo, boolean transcode_only)
/* Do computations that are needed before master selection phase */
{
int ci;
jpeg_component_info *compptr;
long samplesperrow;
JDIMENSION jd_samplesperrow;
#if JPEG_LIB_VERSION >= 70
#if JPEG_LIB_VERSION >= 80
if (!transcode_only)
#endif
jpeg_calc_jpeg_dimensions(cinfo);
#endif
/* Sanity check on image dimensions */
if (cinfo->_jpeg_height <= 0 || cinfo->_jpeg_width <= 0
|| cinfo->num_components <= 0 || cinfo->input_components <= 0)
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
/* Make sure image isn't bigger than I can handle */
if ((long) cinfo->_jpeg_height > (long) JPEG_MAX_DIMENSION ||
(long) cinfo->_jpeg_width > (long) JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
/* Width of an input scanline must be representable as JDIMENSION. */
samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
jd_samplesperrow = (JDIMENSION) samplesperrow;
if ((long) jd_samplesperrow != samplesperrow)
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
/* For now, precision must match compiled-in value... */
if (cinfo->data_precision != BITS_IN_JSAMPLE)
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
/* Check that number of components won't exceed internal array sizes */
if (cinfo->num_components > MAX_COMPONENTS)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPONENTS);
/* Compute maximum sampling factors; check factor validity */
cinfo->max_h_samp_factor = 1;
cinfo->max_v_samp_factor = 1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
ERREXIT(cinfo, JERR_BAD_SAMPLING);
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
compptr->h_samp_factor);
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
compptr->v_samp_factor);
}
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Fill in the correct component_index value; don't rely on application */
compptr->component_index = ci;
/* For compression, we never do DCT scaling. */
#if JPEG_LIB_VERSION >= 70
compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size = DCTSIZE;
#else
compptr->DCT_scaled_size = DCTSIZE;
#endif
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->_jpeg_width * (long) compptr->h_samp_factor,
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->height_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->_jpeg_height * (long) compptr->v_samp_factor,
(long) (cinfo->max_v_samp_factor * DCTSIZE));
/* Size in samples */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->_jpeg_width * (long) compptr->h_samp_factor,
(long) cinfo->max_h_samp_factor);
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->_jpeg_height * (long) compptr->v_samp_factor,
(long) cinfo->max_v_samp_factor);
/* Mark component needed (this flag isn't actually used for compression) */
compptr->component_needed = TRUE;
}
/* Compute number of fully interleaved MCU rows (number of times that
* main controller will call coefficient controller).
*/
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long) cinfo->_jpeg_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
}
per_scan_setup (j_compress_ptr cinfo)
/* Do computations that are needed before processing a JPEG scan */
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
{
int ci, mcublks, tmp;
jpeg_component_info *compptr;
if (cinfo->comps_in_scan == 1) {
/* Noninterleaved (single-component) scan */
compptr = cinfo->cur_comp_info[0];
/* Overall image size in MCUs */
cinfo->MCUs_per_row = compptr->width_in_blocks;
cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
/* For noninterleaved scan, always one block per MCU */
compptr->MCU_width = 1;
compptr->MCU_height = 1;
compptr->MCU_blocks = 1;
compptr->MCU_sample_width = DCTSIZE;
compptr->last_col_width = 1;
/* For noninterleaved scans, it is convenient to define last_row_height
* as the number of block rows present in the last iMCU row.
*/
tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
if (tmp == 0) tmp = compptr->v_samp_factor;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
cinfo->blocks_in_MCU = 1;
cinfo->MCU_membership[0] = 0;
} else {
/* Interleaved (multi-component) scan */
if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
MAX_COMPS_IN_SCAN);
/* Overall image size in MCUs */
cinfo->MCUs_per_row = (JDIMENSION)
jdiv_round_up((long) cinfo->_jpeg_width,
(long) (cinfo->max_h_samp_factor*DCTSIZE));
cinfo->MCU_rows_in_scan = (JDIMENSION)
jdiv_round_up((long) cinfo->_jpeg_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
cinfo->blocks_in_MCU = 0;
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Sampling factors give # of blocks of component in each MCU */
compptr->MCU_width = compptr->h_samp_factor;
compptr->MCU_height = compptr->v_samp_factor;
compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
compptr->MCU_sample_width = compptr->MCU_width * DCTSIZE;
/* Figure number of non-dummy blocks in last MCU column & row */
tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
if (tmp == 0) tmp = compptr->MCU_width;
compptr->last_col_width = tmp;
tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
if (tmp == 0) tmp = compptr->MCU_height;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
mcublks = compptr->MCU_blocks;
if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
while (mcublks-- > 0) {
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
}
}
}
/* Convert restart specified in rows to actual MCU count. */
/* Note that count must fit in 16 bits, so we provide limiting. */
if (cinfo->restart_in_rows > 0) {
long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
}
}
initial_setup (j_decompress_ptr cinfo)
/* Called once, when first SOS marker is reached */
{
int ci;
jpeg_component_info *compptr;
if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||
(long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
/* For now, precision must match compiled-in value... */
if (cinfo->data_precision != BITS_IN_JSAMPLE)
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
/* Check that number of components won't exceed internal array sizes */
if (cinfo->num_components > MAX_COMPONENTS)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPONENTS);
/* Compute maximum sampling factors; check factor validity */
cinfo->max_h_samp_factor = 1;
cinfo->max_v_samp_factor = 1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
ERREXIT(cinfo, JERR_BAD_SAMPLING);
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
compptr->h_samp_factor);
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
compptr->v_samp_factor);
}
/* We initialize DCT_scaled_size and min_DCT_scaled_size to DCTSIZE.
* In the full decompressor, this will be overridden by jdmaster.c;
* but in the transcoder, jdmaster.c is not used, so we must do it here.
*/
cinfo->min_DCT_scaled_size = DCTSIZE;
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_scaled_size = DCTSIZE;
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->height_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) (cinfo->max_v_samp_factor * DCTSIZE));
/* downsampled_width and downsampled_height will also be overridden by
* jdmaster.c if we are doing full decompression. The transcoder library
* doesn't use these values, but the calling application might.
*/
/* Size in samples */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) cinfo->max_h_samp_factor);
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) cinfo->max_v_samp_factor);
/* Mark component needed, until color conversion says otherwise */
compptr->component_needed = TRUE;
/* Mark no quantization table yet saved for component */
compptr->quant_table = NULL;
}
/* Compute number of fully interleaved MCU rows. */
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
/* Decide whether file contains multiple scans */
if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode)
cinfo->inputctl->has_multiple_scans = TRUE;
else
cinfo->inputctl->has_multiple_scans = FALSE;
}
per_scan_setup (j_decompress_ptr cinfo)
/* Do computations that are needed before processing a JPEG scan */
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */
{
int ci, mcublks, tmp;
jpeg_component_info *compptr;
if (cinfo->comps_in_scan == 1) {
/* Noninterleaved (single-component) scan */
compptr = cinfo->cur_comp_info[0];
/* Overall image size in MCUs */
cinfo->MCUs_per_row = compptr->width_in_blocks;
cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
/* For noninterleaved scan, always one block per MCU */
compptr->MCU_width = 1;
compptr->MCU_height = 1;
compptr->MCU_blocks = 1;
compptr->MCU_sample_width = compptr->DCT_scaled_size;
compptr->last_col_width = 1;
/* For noninterleaved scans, it is convenient to define last_row_height
* as the number of block rows present in the last iMCU row.
*/
tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
if (tmp == 0) tmp = compptr->v_samp_factor;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
cinfo->blocks_in_MCU = 1;
cinfo->MCU_membership[0] = 0;
} else {
/* Interleaved (multi-component) scan */
if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
MAX_COMPS_IN_SCAN);
/* Overall image size in MCUs */
cinfo->MCUs_per_row = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width,
(long) (cinfo->max_h_samp_factor*DCTSIZE));
cinfo->MCU_rows_in_scan = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
cinfo->blocks_in_MCU = 0;
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Sampling factors give # of blocks of component in each MCU */
compptr->MCU_width = compptr->h_samp_factor;
compptr->MCU_height = compptr->v_samp_factor;
compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_scaled_size;
/* Figure number of non-dummy blocks in last MCU column & row */
tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
if (tmp == 0) tmp = compptr->MCU_width;
compptr->last_col_width = tmp;
tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
if (tmp == 0) tmp = compptr->MCU_height;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
mcublks = compptr->MCU_blocks;
if (cinfo->blocks_in_MCU + mcublks > D_MAX_BLOCKS_IN_MCU)
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
while (mcublks-- > 0) {
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
}
}
}
}
GLOBAL void
jpeg_calc_output_dimensions (j_decompress_ptr cinfo)
/* Do computations that are needed before master selection phase */
{
#if 0 // JDC: commented out to remove warning
int ci;
jpeg_component_info *compptr;
#endif
/* Prevent application from calling me at wrong times */
if (cinfo->global_state != DSTATE_READY)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
#ifdef IDCT_SCALING_SUPPORTED
/* Compute actual output image dimensions and DCT scaling choices. */
if (cinfo->scale_num * 8 <= cinfo->scale_denom) {
/* Provide 1/8 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 8L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 8L);
cinfo->min_DCT_scaled_size = 1;
} else if (cinfo->scale_num * 4 <= cinfo->scale_denom) {
/* Provide 1/4 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 4L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 4L);
cinfo->min_DCT_scaled_size = 2;
} else if (cinfo->scale_num * 2 <= cinfo->scale_denom) {
/* Provide 1/2 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 2L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 2L);
cinfo->min_DCT_scaled_size = 4;
} else {
/* Provide 1/1 scaling */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
cinfo->min_DCT_scaled_size = DCTSIZE;
}
/* In selecting the actual DCT scaling for each component, we try to
* scale up the chroma components via IDCT scaling rather than upsampling.
* This saves time if the upsampler gets to use 1:1 scaling.
* Note this code assumes that the supported DCT scalings are powers of 2.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
int ssize = cinfo->min_DCT_scaled_size;
while (ssize < DCTSIZE &&
(compptr->h_samp_factor * ssize * 2 <=
cinfo->max_h_samp_factor * cinfo->min_DCT_scaled_size) &&
(compptr->v_samp_factor * ssize * 2 <=
cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size)) {
ssize = ssize * 2;
}
compptr->DCT_scaled_size = ssize;
}
/* Recompute downsampled dimensions of components;
* application needs to know these if using raw downsampled data.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Size in samples, after IDCT scaling */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width *
(long) (compptr->h_samp_factor * compptr->DCT_scaled_size),
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height *
(long) (compptr->v_samp_factor * compptr->DCT_scaled_size),
(long) (cinfo->max_v_samp_factor * DCTSIZE));
}
#else /* !IDCT_SCALING_SUPPORTED */
/* Hardwire it to "no scaling" */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
/* jdinput.c has already initialized DCT_scaled_size to DCTSIZE,
* and has computed unscaled downsampled_width and downsampled_height.
*/
#endif /* IDCT_SCALING_SUPPORTED */
/* Report number of components in selected colorspace. */
/* Probably this should be in the color conversion module... */
switch (cinfo->out_color_space) {
case JCS_GRAYSCALE:
cinfo->out_color_components = 1;
break;
case JCS_RGB:
#if RGB_PIXELSIZE != 3
cinfo->out_color_components = RGB_PIXELSIZE;
break;
#endif /* else share code with YCbCr */
case JCS_YCbCr:
cinfo->out_color_components = 3;
break;
case JCS_CMYK:
case JCS_YCCK:
cinfo->out_color_components = 4;
break;
default: /* else must be same colorspace as in file */
cinfo->out_color_components = cinfo->num_components;
break;
}
cinfo->output_components = (cinfo->quantize_colors ? 1 :
cinfo->out_color_components);
/* See if upsampler will want to emit more than one row at a time */
if (use_merged_upsample(cinfo))
cinfo->rec_outbuf_height = cinfo->max_v_samp_factor;
else
cinfo->rec_outbuf_height = 1;
}
jpeg_core_output_dimensions (j_decompress_ptr cinfo)
/* Do computations that are needed before master selection phase.
* This function is used for transcoding and full decompression.
*/
{
#ifdef IDCT_SCALING_SUPPORTED
int ci;
jpeg_component_info *compptr;
/* Compute actual output image dimensions and DCT scaling choices. */
if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom) {
/* Provide 1/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 1;
cinfo->min_DCT_v_scaled_size = 1;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 2) {
/* Provide 2/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 2L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 2L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 2;
cinfo->min_DCT_v_scaled_size = 2;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 3) {
/* Provide 3/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 3L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 3L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 3;
cinfo->min_DCT_v_scaled_size = 3;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 4) {
/* Provide 4/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 4L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 4L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 4;
cinfo->min_DCT_v_scaled_size = 4;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 5) {
/* Provide 5/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 5L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 5L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 5;
cinfo->min_DCT_v_scaled_size = 5;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 6) {
/* Provide 6/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 6L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 6L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 6;
cinfo->min_DCT_v_scaled_size = 6;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 7) {
/* Provide 7/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 7L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 7L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 7;
cinfo->min_DCT_v_scaled_size = 7;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 8) {
/* Provide 8/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 8L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 8L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 8;
cinfo->min_DCT_v_scaled_size = 8;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 9) {
/* Provide 9/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 9L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 9L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 9;
cinfo->min_DCT_v_scaled_size = 9;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 10) {
/* Provide 10/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 10L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 10L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 10;
cinfo->min_DCT_v_scaled_size = 10;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 11) {
/* Provide 11/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 11L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 11L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 11;
cinfo->min_DCT_v_scaled_size = 11;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 12) {
/* Provide 12/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 12L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 12L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 12;
cinfo->min_DCT_v_scaled_size = 12;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 13) {
/* Provide 13/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 13L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 13L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 13;
cinfo->min_DCT_v_scaled_size = 13;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 14) {
/* Provide 14/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 14L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 14L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 14;
cinfo->min_DCT_v_scaled_size = 14;
} else if (cinfo->scale_num * cinfo->block_size <= cinfo->scale_denom * 15) {
/* Provide 15/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 15L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 15L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 15;
cinfo->min_DCT_v_scaled_size = 15;
} else {
/* Provide 16/block_size scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 16L, (long) cinfo->block_size);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 16L, (long) cinfo->block_size);
cinfo->min_DCT_h_scaled_size = 16;
cinfo->min_DCT_v_scaled_size = 16;
}
/* Recompute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size;
compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size;
}
#else /* !IDCT_SCALING_SUPPORTED */
/* Hardwire it to "no scaling" */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
/* jdinput.c has already initialized DCT_scaled_size,
* and has computed unscaled downsampled_width and downsampled_height.
*/
#endif /* IDCT_SCALING_SUPPORTED */
}
initial_setup (j_decompress_ptr cinfo)
/* Called once, when first SOS marker is reached */
{
int ci;
jpeg_component_info *compptr;
/* Make sure image isn't bigger than I can handle */
if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||
(long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
/* For now, precision must match compiled-in value... */
if (cinfo->data_precision != BITS_IN_JSAMPLE)
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
/* Check that number of components won't exceed internal array sizes */
if (cinfo->num_components > MAX_COMPONENTS)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPONENTS);
/* Compute maximum sampling factors; check factor validity */
cinfo->max_h_samp_factor = 1;
cinfo->max_v_samp_factor = 1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
ERREXIT(cinfo, JERR_BAD_SAMPLING);
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
compptr->h_samp_factor);
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
compptr->v_samp_factor);
}
/* Derive block_size, natural_order, and lim_Se */
if (cinfo->is_baseline || (cinfo->progressive_mode &&
cinfo->comps_in_scan)) { /* no pseudo SOS marker */
cinfo->block_size = DCTSIZE;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
} else
switch (cinfo->Se) {
case (1*1-1):
cinfo->block_size = 1;
cinfo->natural_order = jpeg_natural_order; /* not needed */
cinfo->lim_Se = cinfo->Se;
break;
case (2*2-1):
cinfo->block_size = 2;
cinfo->natural_order = jpeg_natural_order2;
cinfo->lim_Se = cinfo->Se;
break;
case (3*3-1):
cinfo->block_size = 3;
cinfo->natural_order = jpeg_natural_order3;
cinfo->lim_Se = cinfo->Se;
break;
case (4*4-1):
cinfo->block_size = 4;
cinfo->natural_order = jpeg_natural_order4;
cinfo->lim_Se = cinfo->Se;
break;
case (5*5-1):
cinfo->block_size = 5;
cinfo->natural_order = jpeg_natural_order5;
cinfo->lim_Se = cinfo->Se;
break;
case (6*6-1):
cinfo->block_size = 6;
cinfo->natural_order = jpeg_natural_order6;
cinfo->lim_Se = cinfo->Se;
break;
case (7*7-1):
cinfo->block_size = 7;
cinfo->natural_order = jpeg_natural_order7;
cinfo->lim_Se = cinfo->Se;
break;
case (8*8-1):
cinfo->block_size = 8;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (9*9-1):
cinfo->block_size = 9;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (10*10-1):
cinfo->block_size = 10;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (11*11-1):
cinfo->block_size = 11;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (12*12-1):
cinfo->block_size = 12;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (13*13-1):
cinfo->block_size = 13;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (14*14-1):
cinfo->block_size = 14;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (15*15-1):
cinfo->block_size = 15;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
case (16*16-1):
cinfo->block_size = 16;
cinfo->natural_order = jpeg_natural_order;
cinfo->lim_Se = DCTSIZE2-1;
break;
default:
ERREXIT4(cinfo, JERR_BAD_PROGRESSION,
cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);
break;
}
/* We initialize DCT_scaled_size and min_DCT_scaled_size to block_size.
* In the full decompressor,
* this will be overridden by jpeg_calc_output_dimensions in jdmaster.c;
* but in the transcoder,
* jpeg_calc_output_dimensions is not used, so we must do it here.
*/
cinfo->min_DCT_h_scaled_size = cinfo->block_size;
cinfo->min_DCT_v_scaled_size = cinfo->block_size;
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_h_scaled_size = cinfo->block_size;
compptr->DCT_v_scaled_size = cinfo->block_size;
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
compptr->height_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
/* downsampled_width and downsampled_height will also be overridden by
* jdmaster.c if we are doing full decompression. The transcoder library
* doesn't use these values, but the calling application might.
*/
/* Size in samples */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) cinfo->max_h_samp_factor);
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) cinfo->max_v_samp_factor);
/* Mark component needed, until color conversion says otherwise */
compptr->component_needed = TRUE;
/* Mark no quantization table yet saved for component */
compptr->quant_table = NULL;
}
/* Compute number of fully interleaved MCU rows. */
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
/* Decide whether file contains multiple scans */
if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode)
cinfo->inputctl->has_multiple_scans = TRUE;
else
cinfo->inputctl->has_multiple_scans = FALSE;
}
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;
}
}
consume_data_build_huffman_index_progressive(j_decompress_ptr cinfo,
huffman_index *index, int current_scan) {
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;
int factor = 4; // maximum factor is 4.
for (ci = 0; ci < cinfo->comps_in_scan; ci++)
factor = jmin(factor, cinfo->cur_comp_info[ci]->h_samp_factor);
int sample_size = index->MCU_sample_size * factor;
huffman_scan_header *scan_header = index->scan + current_scan;
scan_header->MCU_rows_per_iMCU_row = coef->MCU_rows_per_iMCU_row;
scan_header->MCUs_per_row = jdiv_round_up(cinfo->MCUs_per_row, sample_size);
scan_header->comps_in_scan = cinfo->comps_in_scan;
size_t allocate_size = coef->MCU_rows_per_iMCU_row
* scan_header->MCUs_per_row * sizeof(huffman_offset_data);
scan_header->offset[cinfo->input_iMCU_row] =
(huffman_offset_data *) malloc(allocate_size);
index->mem_used += allocate_size;
huffman_offset_data *offset_data = scan_header->offset[cinfo->input_iMCU_row];
/* 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],
0, // Only need one row buffer
(JDIMENSION) compptr->v_samp_factor, TRUE);
}
/* 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++) {
/* For each MCU, we loop through different color components.
* Then, for each color component we will get a list of pointers to DCT
* blocks in the virtual buffer.
*/
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;
/* Get the list of pointers to DCT blocks in
* the virtual buffer in a color component of the MCU.
*/
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++;
if (cinfo->input_scan_number == 0) {
// need to do pre-zero by ourself.
jzero_far((void FAR *) coef->MCU_buffer[blkn - 1],
(size_t)(SIZEOF(JBLOCK)));
}
}
}
}
// Record huffman bit offset
if (MCU_col_num % sample_size == 0) {
(*cinfo->entropy->get_huffman_decoder_configuration)
(cinfo, offset_data);
++offset_data;
}
/* Try to fetch the MCU. */
if (!(*cinfo->entropy->decode_mcu)(cinfo, coef->MCU_buffer)) {
/* Suspension forced; update state counters and exit */
coef->MCU_vert_offset = yoffset;
coef->MCU_ctr = MCU_col_num;
return JPEG_SUSPENDED;
}
}
/* Completed an MCU row, but perhaps not an iMCU row */
coef->MCU_ctr = 0;
}
(*cinfo->entropy->get_huffman_decoder_configuration)
(cinfo, &scan_header->prev_MCU_offset);
/* Completed the iMCU row, advance counters for next one */
if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) {
start_iMCU_row(cinfo);
return JPEG_ROW_COMPLETED;
}
/* Completed the scan */
(*cinfo->inputctl->finish_input_pass)(cinfo);
return JPEG_SCAN_COMPLETED;
}
jpeg_calc_output_dimensions (j_decompress_ptr cinfo)
/* Do computations that are needed before master selection phase */
{
#ifdef IDCT_SCALING_SUPPORTED
int ci;
jpeg_component_info *compptr;
#endif
/* Prevent application from calling me at wrong times */
if (cinfo->global_state != DSTATE_READY)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Compute core output image dimensions and DCT scaling choices. */
jpeg_core_output_dimensions(cinfo);
#ifdef IDCT_SCALING_SUPPORTED
/* In selecting the actual DCT scaling for each component, we try to
* scale up the chroma components via IDCT scaling rather than upsampling.
* This saves time if the upsampler gets to use 1:1 scaling.
* Note this code adapts subsampling ratios which are powers of 2.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
int ssize = cinfo->_min_DCT_scaled_size;
while (ssize < DCTSIZE &&
((cinfo->max_h_samp_factor * cinfo->_min_DCT_scaled_size) %
(compptr->h_samp_factor * ssize * 2) == 0) &&
((cinfo->max_v_samp_factor * cinfo->_min_DCT_scaled_size) %
(compptr->v_samp_factor * ssize * 2) == 0)) {
ssize = ssize * 2;
}
#if JPEG_LIB_VERSION >= 70
compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size = ssize;
#else
compptr->DCT_scaled_size = ssize;
#endif
}
/* Recompute downsampled dimensions of components;
* application needs to know these if using raw downsampled data.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Size in samples, after IDCT scaling */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width *
(long) (compptr->h_samp_factor * compptr->_DCT_scaled_size),
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height *
(long) (compptr->v_samp_factor * compptr->_DCT_scaled_size),
(long) (cinfo->max_v_samp_factor * DCTSIZE));
}
#else /* !IDCT_SCALING_SUPPORTED */
/* Hardwire it to "no scaling" */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
/* jdinput.c has already initialized DCT_scaled_size to DCTSIZE,
* and has computed unscaled downsampled_width and downsampled_height.
*/
#endif /* IDCT_SCALING_SUPPORTED */
/* Report number of components in selected colorspace. */
/* Probably this should be in the color conversion module... */
switch (cinfo->out_color_space) {
case JCS_GRAYSCALE:
cinfo->out_color_components = 1;
break;
case JCS_RGB:
case JCS_EXT_RGB:
case JCS_EXT_RGBX:
case JCS_EXT_BGR:
case JCS_EXT_BGRX:
case JCS_EXT_XBGR:
case JCS_EXT_XRGB:
case JCS_EXT_RGBA:
case JCS_EXT_BGRA:
case JCS_EXT_ABGR:
case JCS_EXT_ARGB:
cinfo->out_color_components = rgb_pixelsize[cinfo->out_color_space];
break;
case JCS_YCbCr:
case JCS_RGB565:
cinfo->out_color_components = 3;
break;
case JCS_CMYK:
case JCS_YCCK:
cinfo->out_color_components = 4;
break;
default: /* else must be same colorspace as in file */
cinfo->out_color_components = cinfo->num_components;
break;
}
cinfo->output_components = (cinfo->quantize_colors ? 1 :
cinfo->out_color_components);
/* See if upsampler will want to emit more than one row at a time */
if (use_merged_upsample(cinfo))
cinfo->rec_outbuf_height = cinfo->max_v_samp_factor;
else
cinfo->rec_outbuf_height = 1;
}
jpeg_calc_jpeg_dimensions (j_compress_ptr cinfo)
/* Do computations that are needed before master selection phase */
{
#ifdef DCT_SCALING_SUPPORTED
/* Compute actual JPEG image dimensions and DCT scaling choices. */
if (cinfo->scale_num >= cinfo->scale_denom * 8) {
/* Provide 8/1 scaling */
cinfo->jpeg_width = cinfo->image_width << 3;
cinfo->jpeg_height = cinfo->image_height << 3;
cinfo->min_DCT_h_scaled_size = 1;
cinfo->min_DCT_v_scaled_size = 1;
} else if (cinfo->scale_num >= cinfo->scale_denom * 4) {
/* Provide 4/1 scaling */
cinfo->jpeg_width = cinfo->image_width << 2;
cinfo->jpeg_height = cinfo->image_height << 2;
cinfo->min_DCT_h_scaled_size = 2;
cinfo->min_DCT_v_scaled_size = 2;
} else if (cinfo->scale_num * 3 >= cinfo->scale_denom * 8) {
/* Provide 8/3 scaling */
cinfo->jpeg_width = (cinfo->image_width << 1) + (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 2, 3L);
cinfo->jpeg_height = (cinfo->image_height << 1) + (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 2, 3L);
cinfo->min_DCT_h_scaled_size = 3;
cinfo->min_DCT_v_scaled_size = 3;
} else if (cinfo->scale_num >= cinfo->scale_denom * 2) {
/* Provide 2/1 scaling */
cinfo->jpeg_width = cinfo->image_width << 1;
cinfo->jpeg_height = cinfo->image_height << 1;
cinfo->min_DCT_h_scaled_size = 4;
cinfo->min_DCT_v_scaled_size = 4;
} else if (cinfo->scale_num * 5 >= cinfo->scale_denom * 8) {
/* Provide 8/5 scaling */
cinfo->jpeg_width = cinfo->image_width + (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 3, 5L);
cinfo->jpeg_height = cinfo->image_height + (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 3, 5L);
cinfo->min_DCT_h_scaled_size = 5;
cinfo->min_DCT_v_scaled_size = 5;
} else if (cinfo->scale_num * 3 >= cinfo->scale_denom * 4) {
/* Provide 4/3 scaling */
cinfo->jpeg_width = cinfo->image_width + (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 3L);
cinfo->jpeg_height = cinfo->image_height + (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 3L);
cinfo->min_DCT_h_scaled_size = 6;
cinfo->min_DCT_v_scaled_size = 6;
} else if (cinfo->scale_num * 7 >= cinfo->scale_denom * 8) {
/* Provide 8/7 scaling */
cinfo->jpeg_width = cinfo->image_width + (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 7L);
cinfo->jpeg_height = cinfo->image_height + (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 7L);
cinfo->min_DCT_h_scaled_size = 7;
cinfo->min_DCT_v_scaled_size = 7;
} else if (cinfo->scale_num >= cinfo->scale_denom) {
/* Provide 1/1 scaling */
cinfo->jpeg_width = cinfo->image_width;
cinfo->jpeg_height = cinfo->image_height;
cinfo->min_DCT_h_scaled_size = 8;
cinfo->min_DCT_v_scaled_size = 8;
} else if (cinfo->scale_num * 9 >= cinfo->scale_denom * 8) {
/* Provide 8/9 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 8, 9L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 8, 9L);
cinfo->min_DCT_h_scaled_size = 9;
cinfo->min_DCT_v_scaled_size = 9;
} else if (cinfo->scale_num * 5 >= cinfo->scale_denom * 4) {
/* Provide 4/5 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 4, 5L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 4, 5L);
cinfo->min_DCT_h_scaled_size = 10;
cinfo->min_DCT_v_scaled_size = 10;
} else if (cinfo->scale_num * 11 >= cinfo->scale_denom * 8) {
/* Provide 8/11 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 8, 11L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 8, 11L);
cinfo->min_DCT_h_scaled_size = 11;
cinfo->min_DCT_v_scaled_size = 11;
} else if (cinfo->scale_num * 3 >= cinfo->scale_denom * 2) {
/* Provide 2/3 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 2, 3L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 2, 3L);
cinfo->min_DCT_h_scaled_size = 12;
cinfo->min_DCT_v_scaled_size = 12;
} else if (cinfo->scale_num * 13 >= cinfo->scale_denom * 8) {
/* Provide 8/13 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 8, 13L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 8, 13L);
cinfo->min_DCT_h_scaled_size = 13;
cinfo->min_DCT_v_scaled_size = 13;
} else if (cinfo->scale_num * 7 >= cinfo->scale_denom * 4) {
/* Provide 4/7 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 4, 7L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 4, 7L);
cinfo->min_DCT_h_scaled_size = 14;
cinfo->min_DCT_v_scaled_size = 14;
} else if (cinfo->scale_num * 15 >= cinfo->scale_denom * 8) {
/* Provide 8/15 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * 8, 15L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * 8, 15L);
cinfo->min_DCT_h_scaled_size = 15;
cinfo->min_DCT_v_scaled_size = 15;
} else {
/* Provide 1/2 scaling */
cinfo->jpeg_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 2L);
cinfo->jpeg_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 2L);
cinfo->min_DCT_h_scaled_size = 16;
cinfo->min_DCT_v_scaled_size = 16;
}
#else /* !DCT_SCALING_SUPPORTED */
/* Hardwire it to "no scaling" */
cinfo->jpeg_width = cinfo->image_width;
cinfo->jpeg_height = cinfo->image_height;
cinfo->min_DCT_h_scaled_size = DCTSIZE;
cinfo->min_DCT_v_scaled_size = DCTSIZE;
#endif /* DCT_SCALING_SUPPORTED */
}
initial_setup (j_compress_ptr cinfo, boolean transcode_only)
/* Do computations that are needed before master selection phase */
{
int ci, ssize;
jpeg_component_info *compptr;
long samplesperrow;
JDIMENSION jd_samplesperrow;
if (transcode_only)
jpeg_calc_trans_dimensions(cinfo);
else
jpeg_calc_jpeg_dimensions(cinfo);
/* Sanity check on image dimensions */
if (cinfo->jpeg_height <= 0 || cinfo->jpeg_width <= 0 ||
cinfo->num_components <= 0 || cinfo->input_components <= 0)
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
/* Make sure image isn't bigger than I can handle */
if ((long) cinfo->jpeg_height > (long) JPEG_MAX_DIMENSION ||
(long) cinfo->jpeg_width > (long) JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
/* Width of an input scanline must be representable as JDIMENSION. */
samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
jd_samplesperrow = (JDIMENSION) samplesperrow;
if ((long) jd_samplesperrow != samplesperrow)
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
/* For now, precision must match compiled-in value... */
if (cinfo->data_precision != BITS_IN_JSAMPLE)
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
/* Check that number of components won't exceed internal array sizes */
if (cinfo->num_components > MAX_COMPONENTS)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPONENTS);
/* Compute maximum sampling factors; check factor validity */
cinfo->max_h_samp_factor = 1;
cinfo->max_v_samp_factor = 1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
ERREXIT(cinfo, JERR_BAD_SAMPLING);
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
compptr->h_samp_factor);
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
compptr->v_samp_factor);
}
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Fill in the correct component_index value; don't rely on application */
compptr->component_index = ci;
/* In selecting the actual DCT scaling for each component, we try to
* scale down the chroma components via DCT scaling rather than downsampling.
* This saves time if the downsampler gets to use 1:1 scaling.
* Note this code adapts subsampling ratios which are powers of 2.
*/
ssize = 1;
#ifdef DCT_SCALING_SUPPORTED
while (cinfo->min_DCT_h_scaled_size * ssize <=
(cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
(cinfo->max_h_samp_factor % (compptr->h_samp_factor * ssize * 2)) == 0) {
ssize = ssize * 2;
}
#endif
compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size * ssize;
ssize = 1;
#ifdef DCT_SCALING_SUPPORTED
while (cinfo->min_DCT_v_scaled_size * ssize <=
(cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
(cinfo->max_v_samp_factor % (compptr->v_samp_factor * ssize * 2)) == 0) {
ssize = ssize * 2;
}
#endif
compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size * ssize;
/* We don't support DCT ratios larger than 2. */
if (compptr->DCT_h_scaled_size > compptr->DCT_v_scaled_size * 2)
compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size * 2;
else if (compptr->DCT_v_scaled_size > compptr->DCT_h_scaled_size * 2)
compptr->DCT_v_scaled_size = compptr->DCT_h_scaled_size * 2;
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->jpeg_width * (long) compptr->h_samp_factor,
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
compptr->height_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->jpeg_height * (long) compptr->v_samp_factor,
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
/* Size in samples */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->jpeg_width *
(long) (compptr->h_samp_factor * compptr->DCT_h_scaled_size),
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->jpeg_height *
(long) (compptr->v_samp_factor * compptr->DCT_v_scaled_size),
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
/* Mark component needed (this flag isn't actually used for compression) */
compptr->component_needed = TRUE;
}
/* Compute number of fully interleaved MCU rows (number of times that
* main controller will call coefficient controller).
*/
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long) cinfo->jpeg_height,
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
}
calc_output_dimensions (j_decompress_ptr cinfo)
{
#ifdef IDCT_SCALING_SUPPORTED
int ci;
jpeg_component_info *compptr;
/* Compute actual output image dimensions and DCT scaling choices. */
if (cinfo->scale_num * 8 <= cinfo->scale_denom) {
/* Provide 1/8 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 8L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 8L);
cinfo->min_codec_data_unit = 1;
} else if (cinfo->scale_num * 4 <= cinfo->scale_denom) {
/* Provide 1/4 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 4L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 4L);
cinfo->min_codec_data_unit = 2;
} else if (cinfo->scale_num * 2 <= cinfo->scale_denom) {
/* Provide 1/2 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 2L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 2L);
cinfo->min_codec_data_unit = 4;
} else {
/* Provide 1/1 scaling */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
cinfo->min_codec_data_unit = DCTSIZE;
}
/* In selecting the actual DCT scaling for each component, we try to
* scale up the chroma components via IDCT scaling rather than upsampling.
* This saves time if the upsampler gets to use 1:1 scaling.
* Note this code assumes that the supported DCT scalings are powers of 2.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
int ssize = cinfo->min_codec_data_unit;
while (ssize < DCTSIZE &&
(compptr->h_samp_factor * ssize * 2 <=
cinfo->max_h_samp_factor * cinfo->min_codec_data_unit) &&
(compptr->v_samp_factor * ssize * 2 <=
cinfo->max_v_samp_factor * cinfo->min_codec_data_unit)) {
ssize = ssize * 2;
}
compptr->codec_data_unit = ssize;
}
/* Recompute downsampled dimensions of components;
* application needs to know these if using raw downsampled data.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Size in samples, after IDCT scaling */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width *
(long) (compptr->h_samp_factor * compptr->codec_data_unit),
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height *
(long) (compptr->v_samp_factor * compptr->codec_data_unit),
(long) (cinfo->max_v_samp_factor * DCTSIZE));
}
#else /* !IDCT_SCALING_SUPPORTED */
/* Hardwire it to "no scaling" */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
/* jdinput.c has already initialized codec_data_unit to DCTSIZE,
* and has computed unscaled downsampled_width and downsampled_height.
*/
#endif /* IDCT_SCALING_SUPPORTED */
}
jpeg_calc_output_dimensions (j_decompress_ptr cinfo)
/* Do computations that are needed before master selection phase.
* This function is used for full decompression.
*/
{
#ifdef IDCT_SCALING_SUPPORTED
int ci;
jpeg_component_info *compptr;
#endif
/* Prevent application from calling me at wrong times */
if (cinfo->global_state != DSTATE_READY)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Compute core output image dimensions and DCT scaling choices. */
jpeg_core_output_dimensions(cinfo);
#ifdef IDCT_SCALING_SUPPORTED
/* In selecting the actual DCT scaling for each component, we try to
* scale up the chroma components via IDCT scaling rather than upsampling.
* This saves time if the upsampler gets to use 1:1 scaling.
* Note this code adapts subsampling ratios which are powers of 2.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
int ssize = 1;
while (cinfo->min_DCT_h_scaled_size * ssize <=
(cinfo->do_fancy_upsampling ? DCTSIZE : DCTSIZE / 2) &&
(cinfo->max_h_samp_factor % (compptr->h_samp_factor * ssize * 2)) == 0) {
ssize = ssize * 2;
}
compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size * ssize;
ssize = 1;
while (cinfo->min_DCT_v_scaled_size * ssize <=
(cinfo->do_fancy_upsampling ? DCTSIZE : DCTSIZE / 2) &&
(cinfo->max_v_samp_factor % (compptr->v_samp_factor * ssize * 2)) == 0) {
ssize = ssize * 2;
}
compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size * ssize;
/* We don't support IDCT ratios larger than 2. */
if (compptr->DCT_h_scaled_size > compptr->DCT_v_scaled_size * 2)
compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size * 2;
else if (compptr->DCT_v_scaled_size > compptr->DCT_h_scaled_size * 2)
compptr->DCT_v_scaled_size = compptr->DCT_h_scaled_size * 2;
}
/* Recompute downsampled dimensions of components;
* application needs to know these if using raw downsampled data.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Size in samples, after IDCT scaling */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width *
(long) (compptr->h_samp_factor * compptr->DCT_h_scaled_size),
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height *
(long) (compptr->v_samp_factor * compptr->DCT_v_scaled_size),
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
}
#endif /* IDCT_SCALING_SUPPORTED */
/* Report number of components in selected colorspace. */
/* Probably this should be in the color conversion module... */
switch (cinfo->out_color_space) {
case JCS_GRAYSCALE:
cinfo->out_color_components = 1;
break;
case JCS_RGB:
cinfo->out_color_components = RGB_PIXELSIZE;
break;
case JCS_YCbCr:
cinfo->out_color_components = 3;
break;
case JCS_CMYK:
case JCS_YCCK:
cinfo->out_color_components = 4;
break;
default: /* else must be same colorspace as in file */
cinfo->out_color_components = cinfo->num_components;
break;
}
cinfo->output_components = (cinfo->quantize_colors ? 1 :
cinfo->out_color_components);
/* See if upsampler will want to emit more than one row at a time */
if (use_merged_upsample(cinfo))
cinfo->rec_outbuf_height = cinfo->max_v_samp_factor;
else
cinfo->rec_outbuf_height = 1;
}
