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;
}
start_pass_phuff_decoder (j_decompress_ptr cinfo)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
boolean is_DC_band, bad;
int ci, coefi, tbl;
int *coef_bit_ptr;
jpeg_component_info * compptr;
is_DC_band = (cinfo->Ss == 0);
/* Validate scan parameters */
bad = FALSE;
if (is_DC_band) {
if (cinfo->Se != 0)
bad = TRUE;
} else {
/* need not check Ss/Se < 0 since they came from unsigned bytes */
if (cinfo->Ss > cinfo->Se || cinfo->Se >= DCTSIZE2)
bad = TRUE;
/* AC scans may have only one component */
if (cinfo->comps_in_scan != 1)
bad = TRUE;
}
if (cinfo->Ah != 0) {
/* Successive approximation refinement scan: must have Al = Ah-1. */
if (cinfo->Al != cinfo->Ah-1)
bad = TRUE;
}
if (cinfo->Al > 13) /* need not check for < 0 */
bad = TRUE;
/* Arguably the maximum Al value should be less than 13 for 8-bit precision,
* but the spec doesn't say so, and we try to be liberal about what we
* accept. Note: large Al values could result in out-of-range DC
* coefficients during early scans, leading to bizarre displays due to
* overflows in the IDCT math. But we won't crash.
*/
if (bad)
ERREXIT4(cinfo, JERR_BAD_PROGRESSION,
cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);
/* Update progression status, and verify that scan order is legal.
* Note that inter-scan inconsistencies are treated as warnings
* not fatal errors ... not clear if this is right way to behave.
*/
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
int cindex = cinfo->cur_comp_info[ci]->component_index;
coef_bit_ptr = & cinfo->coef_bits[cindex][0];
if (!is_DC_band && coef_bit_ptr[0] < 0) /* AC without prior DC scan */
WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, 0);
for (coefi = cinfo->Ss; coefi <= cinfo->Se; coefi++) {
int expected = (coef_bit_ptr[coefi] < 0) ? 0 : coef_bit_ptr[coefi];
if (cinfo->Ah != expected)
WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi);
coef_bit_ptr[coefi] = cinfo->Al;
}
}
/* Select MCU decoding routine */
if (cinfo->Ah == 0) {
if (is_DC_band)
entropy->pub.decode_mcu = decode_mcu_DC_first;
else
entropy->pub.decode_mcu = decode_mcu_AC_first;
} else {
if (is_DC_band)
entropy->pub.decode_mcu = decode_mcu_DC_refine;
else
entropy->pub.decode_mcu = decode_mcu_AC_refine;
}
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Make sure requested tables are present, and compute derived tables.
* We may build same derived table more than once, but it's not expensive.
*/
if (is_DC_band) {
if (cinfo->Ah == 0) { /* DC refinement needs no table */
tbl = compptr->dc_tbl_no;
jpeg_make_d_derived_tbl(cinfo, TRUE, tbl,
& entropy->derived_tbls[tbl]);
}
} else {
tbl = compptr->ac_tbl_no;
jpeg_make_d_derived_tbl(cinfo, FALSE, tbl,
& entropy->derived_tbls[tbl]);
/* remember the single active table */
entropy->ac_derived_tbl = entropy->derived_tbls[tbl];
}
/* Initialize DC predictions to 0 */
entropy->saved.last_dc_val[ci] = 0;
}
/* Initialize bitread state variables */
entropy->bitstate.bits_left = 0;
entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */
entropy->pub.insufficient_data = FALSE;
/* Initialize private state variables */
entropy->saved.EOBRUN = 0;
/* Initialize restart counter */
entropy->restarts_to_go = cinfo->restart_interval;
}
METHODDEF void
start_pass_phuff_decoder (j_decompress_ptr cinfo)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
boolean is_DC_band, bad;
int ci, coefi, tbl;
int *coef_bit_ptr;
jpeg_component_info * compptr;
is_DC_band = (cinfo->Ss == 0);
/* Validate scan parameters */
bad = FALSE;
if (is_DC_band) {
if (cinfo->Se != 0)
bad = TRUE;
} else {
/* need not check Ss/Se < 0 since they came from unsigned bytes */
if (cinfo->Ss > cinfo->Se || cinfo->Se >= DCTSIZE2)
bad = TRUE;
/* AC scans may have only one component */
if (cinfo->comps_in_scan != 1)
bad = TRUE;
}
if (cinfo->Ah != 0) {
/* Successive approximation refinement scan: must have Al = Ah-1. */
if (cinfo->Al != cinfo->Ah-1)
bad = TRUE;
}
if (cinfo->Al > 13) /* need not check for < 0 */
bad = TRUE;
if (bad)
ERREXIT4(cinfo, JERR_BAD_PROGRESSION,
cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);
/* Update progression status, and verify that scan order is legal.
* Note that inter-scan inconsistencies are treated as warnings
* not fatal errors ... not clear if this is right way to behave.
*/
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
int cindex = cinfo->cur_comp_info[ci]->component_index;
coef_bit_ptr = & cinfo->coef_bits[cindex][0];
if (!is_DC_band && coef_bit_ptr[0] < 0) /* AC without prior DC scan */
WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, 0);
for (coefi = cinfo->Ss; coefi <= cinfo->Se; coefi++) {
int expected = (coef_bit_ptr[coefi] < 0) ? 0 : coef_bit_ptr[coefi];
if (cinfo->Ah != expected)
WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi);
coef_bit_ptr[coefi] = cinfo->Al;
}
}
/* Select MCU decoding routine */
if (cinfo->Ah == 0) {
if (is_DC_band)
entropy->pub.decode_mcu = decode_mcu_DC_first;
else
entropy->pub.decode_mcu = decode_mcu_AC_first;
} else {
if (is_DC_band)
entropy->pub.decode_mcu = decode_mcu_DC_refine;
else
entropy->pub.decode_mcu = decode_mcu_AC_refine;
}
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Make sure requested tables are present, and compute derived tables.
* We may build same derived table more than once, but it's not expensive.
*/
if (is_DC_band) {
if (cinfo->Ah == 0) { /* DC refinement needs no table */
tbl = compptr->dc_tbl_no;
if (tbl < 0 || tbl >= NUM_HUFF_TBLS ||
cinfo->dc_huff_tbl_ptrs[tbl] == NULL)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tbl);
jpeg_make_d_derived_tbl(cinfo, cinfo->dc_huff_tbl_ptrs[tbl],
& entropy->derived_tbls[tbl]);
}
} else {
tbl = compptr->ac_tbl_no;
if (tbl < 0 || tbl >= NUM_HUFF_TBLS ||
cinfo->ac_huff_tbl_ptrs[tbl] == NULL)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tbl);
jpeg_make_d_derived_tbl(cinfo, cinfo->ac_huff_tbl_ptrs[tbl],
& entropy->derived_tbls[tbl]);
/* remember the single active table */
entropy->ac_derived_tbl = entropy->derived_tbls[tbl];
}
/* Initialize DC predictions to 0 */
entropy->saved.last_dc_val[ci] = 0;
}
/* Initialize bitread state variables */
entropy->bitstate.bits_left = 0;
entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */
entropy->bitstate.printed_eod = FALSE;
/* Initialize private state variables */
entropy->saved.EOBRUN = 0;
/* Initialize restart counter */
entropy->restarts_to_go = cinfo->restart_interval;
}
