jpeg_simple_progression (j_compress_ptr cinfo)
{
int ncomps = cinfo->num_components;
int nscans;
jpeg_scan_info * scanptr;
/* Safety check to ensure start_compress not called yet. */
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Figure space needed for script. Calculation must match code below! */
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
/* Custom script for YCbCr color images. */
nscans = 10;
} else {
/* All-purpose script for other color spaces. */
if (ncomps > MAX_COMPS_IN_SCAN)
nscans = 6 * ncomps; /* 2 DC + 4 AC scans per component */
else
nscans = 2 + 4 * ncomps; /* 2 DC scans; 4 AC scans per component */
}
/* Allocate space for script.
* We need to put it in the permanent pool in case the application performs
* multiple compressions without changing the settings. To avoid a memory
* leak if jpeg_simple_progression is called repeatedly for the same JPEG
* object, we try to re-use previously allocated space, and we allocate
* enough space to handle YCbCr even if initially asked for grayscale.
*/
if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) {
cinfo->script_space_size = MAX(nscans, 10);
cinfo->script_space = (jpeg_scan_info *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
cinfo->script_space_size * SIZEOF(jpeg_scan_info));
}
scanptr = cinfo->script_space;
cinfo->scan_info = scanptr;
cinfo->num_scans = nscans;
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
/* Custom script for YCbCr color images. */
/* Initial DC scan */
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
/* Initial AC scan: get some luma data out in a hurry */
scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2);
/* Chroma data is too small to be worth expending many scans on */
scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1);
/* Complete spectral selection for luma AC */
scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2);
/* Refine next bit of luma AC */
scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1);
/* Finish DC successive approximation */
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
/* Finish AC successive approximation */
scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0);
/* Luma bottom bit comes last since it's usually largest scan */
scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0);
} else {
/* All-purpose script for other color spaces. */
/* Successive approximation first pass */
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2);
scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2);
/* Successive approximation second pass */
scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1);
/* Successive approximation final pass */
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0);
}
}
jpeg_search_progression (j_compress_ptr cinfo)
{
int ncomps = cinfo->num_components;
int nscans;
jpeg_scan_info * scanptr;
int Al;
int frequency_split[] = { 2, 8, 5, 12, 18 };
int i;
/* Safety check to ensure start_compress not called yet. */
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Figure space needed for script. Calculation must match code below! */
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
/* Custom script for YCbCr color images. */
nscans = 64;
} else if (ncomps == 1) {
nscans = 23;
} else {
cinfo->num_scans_luma = 0;
return FALSE;
}
/* Allocate space for script.
* We need to put it in the permanent pool in case the application performs
* multiple compressions without changing the settings. To avoid a memory
* leak if jpeg_simple_progression is called repeatedly for the same JPEG
* object, we try to re-use previously allocated space, and we allocate
* enough space to handle YCbCr even if initially asked for grayscale.
*/
if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) {
cinfo->script_space_size = MAX(nscans, 64);
cinfo->script_space = (jpeg_scan_info *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
cinfo->script_space_size * SIZEOF(jpeg_scan_info));
}
scanptr = cinfo->script_space;
cinfo->scan_info = scanptr;
cinfo->num_scans = nscans;
cinfo->Al_max_luma = 3;
cinfo->num_scans_luma_dc = 1;
cinfo->num_frequency_splits = 5;
cinfo->num_scans_luma = cinfo->num_scans_luma_dc + (3 * cinfo->Al_max_luma + 2) + (2 * cinfo->num_frequency_splits + 1);
/* 23 scans for luma */
/* 1 scan for DC */
/* 11 scans to determine successive approximation */
/* 11 scans to determine frequency approximation */
/* after 12 scans need to update following 11 */
/* after 23 scans need to determine which to keep */
/* last 4 done conditionally */
/* luma DC by itself */
if (cinfo->one_dc_scan)
scanptr = fill_dc_scans(scanptr, ncomps, 0, 0);
else
scanptr = fill_dc_scans(scanptr, 1, 0, 0);
scanptr = fill_a_scan(scanptr, 0, 1, 8, 0, 0);
scanptr = fill_a_scan(scanptr, 0, 9, 63, 0, 0);
for (Al = 0; Al < cinfo->Al_max_luma; Al++) {
scanptr = fill_a_scan(scanptr, 0, 1, 63, Al+1, Al);
scanptr = fill_a_scan(scanptr, 0, 1, 8, 0, Al+1);
scanptr = fill_a_scan(scanptr, 0, 9, 63, 0, Al+1);
}
scanptr = fill_a_scan(scanptr, 0, 1, 63, 0, 0);
for (i = 0; i < cinfo->num_frequency_splits; i++) {
scanptr = fill_a_scan(scanptr, 0, 1, frequency_split[i], 0, 0);
scanptr = fill_a_scan(scanptr, 0, frequency_split[i]+1, 63, 0, 0);
}
if (ncomps == 1) {
cinfo->Al_max_chroma = 0;
cinfo->num_scans_chroma_dc = 0;
} else {
cinfo->Al_max_chroma = 2;
cinfo->num_scans_chroma_dc = 3;
/* 41 scans for chroma */
/* chroma DC combined */
scanptr = fill_a_scan_pair(scanptr, 1, 0, 0, 0, 0);
/* chroma DC separate */
scanptr = fill_a_scan(scanptr, 1, 0, 0, 0, 0);
scanptr = fill_a_scan(scanptr, 2, 0, 0, 0, 0);
scanptr = fill_a_scan(scanptr, 1, 1, 8, 0, 0);
scanptr = fill_a_scan(scanptr, 1, 9, 63, 0, 0);
scanptr = fill_a_scan(scanptr, 2, 1, 8, 0, 0);
scanptr = fill_a_scan(scanptr, 2, 9, 63, 0, 0);
for (Al = 0; Al < cinfo->Al_max_chroma; Al++) {
scanptr = fill_a_scan(scanptr, 1, 1, 63, Al+1, Al);
scanptr = fill_a_scan(scanptr, 2, 1, 63, Al+1, Al);
scanptr = fill_a_scan(scanptr, 1, 1, 8, 0, Al+1);
scanptr = fill_a_scan(scanptr, 1, 9, 63, 0, Al+1);
scanptr = fill_a_scan(scanptr, 2, 1, 8, 0, Al+1);
scanptr = fill_a_scan(scanptr, 2, 9, 63, 0, Al+1);
}
scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 0);
scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 0);
for (i = 0; i < cinfo->num_frequency_splits; i++) {
scanptr = fill_a_scan(scanptr, 1, 1, frequency_split[i], 0, 0);
scanptr = fill_a_scan(scanptr, 1, frequency_split[i]+1, 63, 0, 0);
scanptr = fill_a_scan(scanptr, 2, 1, frequency_split[i], 0, 0);
scanptr = fill_a_scan(scanptr, 2, frequency_split[i]+1, 63, 0, 0);
}
}
return TRUE;
}
jpeg_simple_progression (j_compress_ptr cinfo)
{
int ncomps = cinfo->num_components;
int nscans;
jpeg_scan_info * scanptr;
/* Safety check to ensure start_compress not called yet. */
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Figure space needed for script. Calculation must match code below! */
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
/* Custom script for YCbCr color images. */
nscans = 10;
} else {
/* All-purpose script for other color spaces. */
if (ncomps > MAX_COMPS_IN_SCAN)
nscans = 6 * ncomps; /* 2 DC + 4 AC scans per component */
else
nscans = 2 + 4 * ncomps; /* 2 DC scans; 4 AC scans per component */
}
/* Allocate space for script. */
/* We use permanent pool just in case application re-uses script. */
scanptr = (jpeg_scan_info *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
nscans * SIZEOF(jpeg_scan_info));
cinfo->scan_info = scanptr;
cinfo->num_scans = nscans;
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
/* Custom script for YCbCr color images. */
/* Initial DC scan */
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
/* Initial AC scan: get some luma data out in a hurry */
scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2);
/* Chroma data is too small to be worth expending many scans on */
scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1);
/* Complete spectral selection for luma AC */
scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2);
/* Refine next bit of luma AC */
scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1);
/* Finish DC successive approximation */
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
/* Finish AC successive approximation */
scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0);
/* Luma bottom bit comes last since it's usually largest scan */
scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0);
} else {
/* All-purpose script for other color spaces. */
/* Successive approximation first pass */
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2);
scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2);
/* Successive approximation second pass */
scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1);
/* Successive approximation final pass */
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0);
}
}
jpeg_simple_progression (j_compress_ptr cinfo)
{
int ncomps = cinfo->num_components;
int nscans;
jpeg_scan_info * scanptr;
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
nscans = 10;
} else {
if (ncomps > MAX_COMPS_IN_SCAN)
nscans = 6 * ncomps;
else
nscans = 2 + 4 * ncomps;
}
if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) {
cinfo->script_space_size = MAX(nscans, 10);
cinfo->script_space = (jpeg_scan_info *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
cinfo->script_space_size * SIZEOF(jpeg_scan_info));
}
scanptr = cinfo->script_space;
cinfo->scan_info = scanptr;
cinfo->num_scans = nscans;
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2);
scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1);
scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2);
scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1);
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0);
scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0);
} else {
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2);
scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2);
scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1);
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0);
}
}
