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 = &coef->pub;
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;
}
}
GLOBAL void
jzero_far (void FAR * target, size_t bytestozero)
/* Zero out a chunk of FAR memory. */
/* This might be sample-array data, block-array data, or alloc_large data. */
{
#ifdef FMEMZERO
FMEMZERO(target, bytestozero);
#else
register char FAR * ptr = (char FAR *) target;
register size_t count;
for (count = bytestozero; count > 0; count--) {
*ptr++ = 0;
}
#endif
}
start_pass_1_quant( j_decompress_ptr cinfo, boolean is_pre_scan ) {
my_cquantize_ptr cquantize = ( my_cquantize_ptr ) cinfo->cquantize;
size_t arraysize;
int i;
/* Install my colormap. */
cinfo->colormap = cquantize->sv_colormap;
cinfo->actual_number_of_colors = cquantize->sv_actual;
/* Initialize for desired dithering mode. */
switch( cinfo->dither_mode ) {
case JDITHER_NONE:
if( cinfo->out_color_components == 3 ) {
cquantize->pub.color_quantize = color_quantize3;
} else {
cquantize->pub.color_quantize = color_quantize;
}
break;
case JDITHER_ORDERED:
if( cinfo->out_color_components == 3 ) {
cquantize->pub.color_quantize = quantize3_ord_dither;
} else {
cquantize->pub.color_quantize = quantize_ord_dither;
}
cquantize->row_index = 0; /* initialize state for ordered dither */
/* If user changed to ordered dither from another mode,
* we must recreate the color index table with padding.
* This will cost extra space, but probably isn't very likely.
*/
if( ! cquantize->is_padded ) {
create_colorindex( cinfo );
}
/* Create ordered-dither tables if we didn't already. */
if( cquantize->odither[0] == NULL ) {
create_odither_tables( cinfo );
}
break;
case JDITHER_FS:
cquantize->pub.color_quantize = quantize_fs_dither;
cquantize->on_odd_row = FALSE; /* initialize state for F-S dither */
/* Allocate Floyd-Steinberg workspace if didn't already. */
if( cquantize->fserrors[0] == NULL ) {
alloc_fs_workspace( cinfo );
}
/* Initialize the propagated errors to zero. */
arraysize = ( size_t )( ( cinfo->output_width + 2 ) * SIZEOF( FSERROR ) );
for( i = 0; i < cinfo->out_color_components; i++ ) {
FMEMZERO( ( void FAR * ) cquantize->fserrors[i], arraysize );
}
break;
default:
ERREXIT( cinfo, JERR_NOT_COMPILED );
break;
}
}
quantize_ord_dither(j_decompress_ptr cinfo, JSAMPARRAY input_buf,
JSAMPARRAY output_buf, int num_rows)
/* General case, with ordered dithering */
{
my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
register JSAMPROW input_ptr;
register JSAMPROW output_ptr;
JSAMPROW colorindex_ci;
int* dither; /* points to active row of dither matrix */
int row_index, col_index; /* current indexes into dither matrix */
int nc = cinfo->out_color_components;
int ci;
int row;
JDIMENSION col;
JDIMENSION width = cinfo->output_width;
for (row = 0; row < num_rows; row++)
{
/* Initialize output values to 0 so can process components separately */
FMEMZERO((void FAR*) output_buf[row],
(size_t)(width * SIZEOF(JSAMPLE)));
row_index = cquantize->row_index;
for (ci = 0; ci < nc; ci++)
{
input_ptr = input_buf[row] + ci;
output_ptr = output_buf[row];
colorindex_ci = cquantize->colorindex[ci];
dither = cquantize->odither[ci][row_index];
col_index = 0;
for (col = width; col > 0; col--)
{
/* Form pixel value + dither, range-limit to 0..MAXJSAMPLE,
* select output value, accumulate into output code for this pixel.
* Range-limiting need not be done explicitly, as we have extended
* the colorindex table to produce the right answers for out-of-range
* inputs. The maximum dither is +- MAXJSAMPLE; this sets the
* required amount of padding.
*/
*output_ptr += colorindex_ci[GETJSAMPLE(*input_ptr) + dither[col_index]];
input_ptr += nc;
output_ptr++;
col_index = (col_index + 1) & ODITHER_MASK;
}
}
/* Advance row index for next row */
row_index = (row_index + 1) & ODITHER_MASK;
cquantize->row_index = row_index;
}
}
quantize_fs_dither( j_decompress_ptr cinfo, JSAMPARRAY input_buf,
JSAMPARRAY output_buf, int num_rows )
/* General case, with Floyd-Steinberg dithering */
{
my_cquantize_ptr cquantize = ( my_cquantize_ptr ) cinfo->cquantize;
register LOCFSERROR cur; /* current error or pixel value */
LOCFSERROR belowerr; /* error for pixel below cur */
LOCFSERROR bpreverr; /* error for below/prev col */
LOCFSERROR bnexterr; /* error for below/next col */
LOCFSERROR delta;
register FSERRPTR errorptr; /* => fserrors[] at column before current */
register JSAMPROW input_ptr;
register JSAMPROW output_ptr;
JSAMPROW colorindex_ci;
JSAMPROW colormap_ci;
int pixcode;
int nc = cinfo->out_color_components;
int dir; /* 1 for left-to-right, -1 for right-to-left */
int dirnc; /* dir * nc */
int ci;
int row;
JDIMENSION col;
JDIMENSION width = cinfo->output_width;
JSAMPLE *range_limit = cinfo->sample_range_limit;
SHIFT_TEMPS
for( row = 0; row < num_rows; row++ ) {
/* Initialize output values to 0 so can process components separately */
FMEMZERO( ( void FAR * ) output_buf[row],
( size_t )( width * SIZEOF( JSAMPLE ) ) );
for( ci = 0; ci < nc; ci++ ) {
input_ptr = input_buf[row] + ci;
output_ptr = output_buf[row];
if( cquantize->on_odd_row ) {
/* work right to left in this row */
input_ptr += ( width - 1 ) * nc; /* so point to rightmost pixel */
output_ptr += width - 1;
dir = -1;
dirnc = -nc;
errorptr = cquantize->fserrors[ci] + ( width + 1 ); /* => entry after last column */
} else {
/* work left to right in this row */
dir = 1;
dirnc = nc;
errorptr = cquantize->fserrors[ci]; /* => entry before first column */
}
colorindex_ci = cquantize->colorindex[ci];
colormap_ci = cquantize->sv_colormap[ci];
/* Preset error values: no error propagated to first pixel from left */
cur = 0;
/* and no error propagated to row below yet */
belowerr = bpreverr = 0;
for( col = width; col > 0; col-- ) {
/* cur holds the error propagated from the previous pixel on the
* current line. Add the error propagated from the previous line
* to form the complete error correction term for this pixel, and
* round the error term (which is expressed * 16) to an integer.
* RIGHT_SHIFT rounds towards minus infinity, so adding 8 is correct
* for either sign of the error value.
* Note: errorptr points to *previous* column's array entry.
*/
cur = RIGHT_SHIFT( cur + errorptr[dir] + 8, 4 );
/* Form pixel value + error, and range-limit to 0..MAXJSAMPLE.
* The maximum error is +- MAXJSAMPLE; this sets the required size
* of the range_limit array.
*/
cur += GETJSAMPLE( *input_ptr );
cur = GETJSAMPLE( range_limit[cur] );
/* Select output value, accumulate into output code for this pixel */
pixcode = GETJSAMPLE( colorindex_ci[cur] );
*output_ptr += ( JSAMPLE ) pixcode;
/* Compute actual representation error at this pixel */
/* Note: we can do this even though we don't have the final */
/* pixel code, because the colormap is orthogonal. */
cur -= GETJSAMPLE( colormap_ci[pixcode] );
/* Compute error fractions to be propagated to adjacent pixels.
* Add these into the running sums, and simultaneously shift the
* next-line error sums left by 1 column.
*/
bnexterr = cur;
delta = cur * 2;
cur += delta; /* form error * 3 */
errorptr[0] = ( FSERROR )( bpreverr + cur );
cur += delta; /* form error * 5 */
bpreverr = belowerr + cur;
belowerr = bnexterr;
cur += delta; /* form error * 7 */
/* At this point cur contains the 7/16 error value to be propagated
* to the next pixel on the current line, and all the errors for the
* next line have been shifted over. We are therefore ready to move on.
*/
input_ptr += dirnc; /* advance input ptr to next column */
output_ptr += dir; /* advance output ptr to next column */
errorptr += dir; /* advance errorptr to current column */
}
/* Post-loop cleanup: we must unload the final error value into the
* final fserrors[] entry. Note we need not unload belowerr because
* it is for the dummy column before or after the actual array.
*/
errorptr[0] = ( FSERROR ) bpreverr; /* unload prev err into array */
}
cquantize->on_odd_row = ( cquantize->on_odd_row ? FALSE : TRUE );
}
}
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);
}
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;
}
jinit_d_coef_controller(j_decompress_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_d_coef_controller*) coef;
coef->pub.start_input_pass = start_input_pass;
coef->pub.start_output_pass = start_output_pass;
#ifdef BLOCK_SMOOTHING_SUPPORTED
coef->coef_bits_latch = NULL;
#endif
/* Create the coefficient buffer. */
if (need_full_buffer)
{
#ifdef D_MULTISCAN_FILES_SUPPORTED
/* Allocate a full-image virtual array for each component, */
/* padded to a multiple of samp_factor DCT blocks in each direction. */
/* Note we ask for a pre-zeroed array. */
int ci, access_rows;
jpeg_component_info* compptr;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++)
{
access_rows = compptr->v_samp_factor;
#ifdef BLOCK_SMOOTHING_SUPPORTED
/* If block smoothing could be used, need a bigger window */
if (cinfo->progressive_mode)
{
access_rows *= 3;
}
#endif
coef->whole_image[ci] = (*cinfo->mem->request_virt_barray)
((j_common_ptr) cinfo, JPOOL_IMAGE, TRUE,
(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) access_rows);
}
coef->pub.consume_data = consume_data;
coef->pub.decompress_data = decompress_data;
coef->pub.coef_arrays = coef->whole_image; /* link to virtual arrays */
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#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,
D_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
for (i = 0; i < D_MAX_BLOCKS_IN_MCU; i++)
{
coef->MCU_buffer[i] = buffer + i;
}
if (cinfo->lim_Se == 0) /* DC only case: want to bypass later */
FMEMZERO((void FAR*) buffer,
(size_t)(D_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK)));
coef->pub.consume_data = dummy_consume_data;
coef->pub.decompress_data = decompress_onepass;
coef->pub.coef_arrays = NULL; /* flag for no virtual arrays */
}
}
