/**
* jbig2_add_page_result: composite a decoding result onto a page
*
* this is called to add the results of segment decode (when it
* is an image) to a page image buffer
**/
int
jbig2_page_add_result(Jbig2Ctx *ctx, Jbig2Page *page, Jbig2Image *image,
int x, int y, Jbig2ComposeOp op)
{
/* ensure image exists first */
if (page->image == NULL)
{
jbig2_error(ctx, JBIG2_SEVERITY_WARNING, -1,
"page info possibly missing, no image defined");
return 0;
}
/* grow the page to accomodate a new stripe if necessary */
if (page->striped) {
int new_height = y + image->height + page->end_row;
if (page->image->height < new_height) {
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, -1,
"growing page buffer to %d rows "
"to accomodate new stripe", new_height);
jbig2_image_resize(ctx, page->image,
page->image->width, new_height);
}
}
jbig2_image_compose(ctx, page->image, image,
x, y + page->end_row, op);
return 0;
}
/**
* jbig2_add_page_result: composite a decoding result onto a page
*
* this is called to add the results of segment decode (when it
* is an image) to a page image buffer
**/
int
jbig2_page_add_result(Jbig2Ctx *ctx, Jbig2Page *page, Jbig2Image *image,
int x, int y, Jbig2ComposeOp op)
{
/* grow the page to accomodate a new stripe if necessary */
if (page->striped) {
int new_height = y + image->height + page->end_row;
if (page->image->height < new_height) {
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, -1,
"growing page buffer to %d rows "
"to accomodate new stripe", new_height);
jbig2_image_resize(ctx, page->image,
page->image->width, new_height);
}
}
jbig2_image_compose(ctx, page->image, image,
x, y + page->end_row, JBIG2_COMPOSE_OR);
return 0;
}
/**
* jbig2_decode_text_region: decode a text region segment
*
* @ctx: jbig2 decoder context
* @segment: jbig2 segment (header) structure
* @params: parameters from the text region header
* @dicts: an array of referenced symbol dictionaries
* @n_dicts: the number of referenced symbol dictionaries
* @image: image structure in which to store the decoded region bitmap
* @data: pointer to text region data to be decoded
* @size: length of text region data
*
* Implements the text region decoding procedure
* described in section 6.4 of the JBIG2 spec.
*
* returns: 0 on success
**/
int
jbig2_decode_text_region(Jbig2Ctx *ctx, Jbig2Segment *segment,
const Jbig2TextRegionParams *params,
const Jbig2SymbolDict * const *dicts, const int n_dicts,
Jbig2Image *image,
const byte *data, const size_t size,
Jbig2ArithCx *GR_stats, Jbig2ArithState *as, Jbig2WordStream *ws)
{
/* relevent bits of 6.4.4 */
uint32_t NINSTANCES;
uint32_t ID;
int32_t STRIPT;
int32_t FIRSTS;
int32_t DT;
int32_t DFS;
int32_t IDS;
int32_t CURS;
int32_t CURT;
int S,T;
int x,y;
bool first_symbol;
uint32_t index, SBNUMSYMS;
Jbig2Image *IB = NULL;
Jbig2HuffmanState *hs = NULL;
Jbig2HuffmanTable *SBSYMCODES = NULL;
int code = 0;
int RI;
SBNUMSYMS = 0;
for (index = 0; index < n_dicts; index++) {
SBNUMSYMS += dicts[index]->n_symbols;
}
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number,
"symbol list contains %d glyphs in %d dictionaries", SBNUMSYMS, n_dicts);
if (params->SBHUFF) {
Jbig2HuffmanTable *runcodes = NULL;
Jbig2HuffmanParams runcodeparams;
Jbig2HuffmanLine runcodelengths[35];
Jbig2HuffmanLine *symcodelengths = NULL;
Jbig2HuffmanParams symcodeparams;
int err, len, range, r;
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number,
"huffman coded text region");
hs = jbig2_huffman_new(ctx, ws);
if (hs == NULL)
{
jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"failed to allocate storage for text region");
return -1;
}
/* 7.4.3.1.7 - decode symbol ID Huffman table */
/* this is actually part of the segment header, but it is more
convenient to handle it here */
/* parse and build the runlength code huffman table */
for (index = 0; index < 35; index++) {
runcodelengths[index].PREFLEN = jbig2_huffman_get_bits(hs, 4);
runcodelengths[index].RANGELEN = 0;
runcodelengths[index].RANGELOW = index;
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number,
" read runcode%d length %d", index, runcodelengths[index].PREFLEN);
}
runcodeparams.HTOOB = 0;
runcodeparams.lines = runcodelengths;
runcodeparams.n_lines = 35;
runcodes = jbig2_build_huffman_table(ctx, &runcodeparams);
if (runcodes == NULL) {
jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"error constructing symbol id runcode table!");
code = -1;
goto cleanup1;
}
/* decode the symbol id codelengths using the runlength table */
symcodelengths = jbig2_new(ctx, Jbig2HuffmanLine, SBNUMSYMS);
if (symcodelengths == NULL) {
jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"memory allocation failure reading symbol ID huffman table!");
code = -1;
goto cleanup1;
}
index = 0;
while (index < SBNUMSYMS) {
code = jbig2_huffman_get(hs, runcodes, &err);
if (err != 0 || code < 0 || code >= 35) {
jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"error reading symbol ID huffman table!");
code = err ? err : -1;
goto cleanup1;
}
if (code < 32) {
len = code;
range = 1;
} else {
if (code == 32) {
len = symcodelengths[index-1].PREFLEN;
if (index < 1) {
jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"error decoding symbol id table: run length with no antecedent!");
code = -1;
goto cleanup1;
}
} else {
len = 0; /* code == 33 or 34 */
}
if (code == 32) range = jbig2_huffman_get_bits(hs, 2) + 3;
else if (code == 33) range = jbig2_huffman_get_bits(hs, 3) + 3;
else if (code == 34) range = jbig2_huffman_get_bits(hs, 7) + 11;
}
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number,
" read runcode%d at index %d (length %d range %d)", code, index, len, range);
if (index+range > SBNUMSYMS) {
jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"runlength extends %d entries beyond the end of symbol id table!",
index+range - SBNUMSYMS);
range = SBNUMSYMS - index;
}
for (r = 0; r < range; r++) {
symcodelengths[index+r].PREFLEN = len;
symcodelengths[index+r].RANGELEN = 0;
symcodelengths[index+r].RANGELOW = index + r;
}
index += r;
}
if (index < SBNUMSYMS) {
jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"runlength codes do not cover the available symbol set");
}
symcodeparams.HTOOB = 0;
symcodeparams.lines = symcodelengths;
symcodeparams.n_lines = SBNUMSYMS;
/* skip to byte boundary */
jbig2_huffman_skip(hs);
/* finally, construct the symbol id huffman table itself */
SBSYMCODES = jbig2_build_huffman_table(ctx, &symcodeparams);
cleanup1:
jbig2_free(ctx->allocator, symcodelengths);
jbig2_release_huffman_table(ctx, runcodes);
if (SBSYMCODES == NULL) {
jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"could not construct Symbol ID huffman table!");
jbig2_huffman_free(ctx, hs);
return ((code != 0) ? code : -1);
}
}
/* 6.4.5 (1) */
jbig2_image_clear(ctx, image, params->SBDEFPIXEL);
/* 6.4.6 */
if (params->SBHUFF) {
STRIPT = jbig2_huffman_get(hs, params->SBHUFFDT, &code);
} else {
code = jbig2_arith_int_decode(params->IADT, as, &STRIPT);
if (code < 0) goto cleanup2;
}
/* 6.4.5 (2) */
STRIPT *= -(params->SBSTRIPS);
FIRSTS = 0;
NINSTANCES = 0;
/* 6.4.5 (3) */
while (NINSTANCES < params->SBNUMINSTANCES) {
/* (3b) */
if (params->SBHUFF) {
DT = jbig2_huffman_get(hs, params->SBHUFFDT, &code);
} else {
code = jbig2_arith_int_decode(params->IADT, as, &DT);
if (code < 0) goto cleanup2;
}
DT *= params->SBSTRIPS;
STRIPT += DT;
first_symbol = TRUE;
/* 6.4.5 (3c) - decode symbols in strip */
for (;;) {
/* (3c.i) */
if (first_symbol) {
/* 6.4.7 */
if (params->SBHUFF) {
DFS = jbig2_huffman_get(hs, params->SBHUFFFS, &code);
} else {
code = jbig2_arith_int_decode(params->IAFS, as, &DFS);
if (code < 0) goto cleanup2;
}
FIRSTS += DFS;
CURS = FIRSTS;
first_symbol = FALSE;
} else {
/* (3c.ii) / 6.4.8 */
if (params->SBHUFF) {
IDS = jbig2_huffman_get(hs, params->SBHUFFDS, &code);
} else {
code = jbig2_arith_int_decode(params->IADS, as, &IDS);
}
if (code) {
break;
}
CURS += IDS + params->SBDSOFFSET;
}
/* (3c.iii) / 6.4.9 */
if (params->SBSTRIPS == 1) {
CURT = 0;
} else if (params->SBHUFF) {
CURT = jbig2_huffman_get_bits(hs, params->LOGSBSTRIPS);
} else {
code = jbig2_arith_int_decode(params->IAIT, as, &CURT);
if (code < 0) goto cleanup2;
}
T = STRIPT + CURT;
/* (3b.iv) / 6.4.10 - decode the symbol id */
if (params->SBHUFF) {
ID = jbig2_huffman_get(hs, SBSYMCODES, &code);
} else {
code = jbig2_arith_iaid_decode(params->IAID, as, (int *)&ID);
if (code < 0) goto cleanup2;
}
if (ID >= SBNUMSYMS) {
return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"symbol id out of range! (%d/%d)", ID, SBNUMSYMS);
}
/* (3c.v) / 6.4.11 - look up the symbol bitmap IB */
{
uint32_t id = ID;
index = 0;
while (id >= dicts[index]->n_symbols)
id -= dicts[index++]->n_symbols;
IB = jbig2_image_clone(ctx, dicts[index]->glyphs[id]);
}
if (params->SBREFINE) {
if (params->SBHUFF) {
RI = jbig2_huffman_get_bits(hs, 1);
} else {
code = jbig2_arith_int_decode(params->IARI, as, &RI);
if (code < 0) goto cleanup2;
}
} else {
RI = 0;
}
if (RI) {
Jbig2RefinementRegionParams rparams;
Jbig2Image *IBO;
int32_t RDW, RDH, RDX, RDY;
Jbig2Image *refimage;
int BMSIZE = 0;
int code1 = 0;
int code2 = 0;
int code3 = 0;
int code4 = 0;
int code5 = 0;
/* 6.4.11 (1, 2, 3, 4) */
if (!params->SBHUFF) {
code1 = jbig2_arith_int_decode(params->IARDW, as, &RDW);
code2 = jbig2_arith_int_decode(params->IARDH, as, &RDH);
code3 = jbig2_arith_int_decode(params->IARDX, as, &RDX);
code4 = jbig2_arith_int_decode(params->IARDY, as, &RDY);
} else {
RDW = jbig2_huffman_get(hs, params->SBHUFFRDW, &code1);
RDH = jbig2_huffman_get(hs, params->SBHUFFRDH, &code2);
RDX = jbig2_huffman_get(hs, params->SBHUFFRDX, &code3);
RDY = jbig2_huffman_get(hs, params->SBHUFFRDY, &code4);
BMSIZE = jbig2_huffman_get(hs, params->SBHUFFRSIZE, &code5);
jbig2_huffman_skip(hs);
}
if ((code1 < 0) || (code2 < 0) || (code3 < 0) || (code4 < 0) || (code5 < 0))
{
code = jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"failed to decode data");
goto cleanup2;
}
/* 6.4.11 (6) */
IBO = IB;
refimage = jbig2_image_new(ctx, IBO->width + RDW,
IBO->height + RDH);
if (refimage == NULL) {
jbig2_image_release(ctx, IBO);
if (params->SBHUFF) {
jbig2_release_huffman_table(ctx, SBSYMCODES);
}
return jbig2_error(ctx, JBIG2_SEVERITY_FATAL,
segment->number,
"couldn't allocate reference image");
}
/* Table 12 */
rparams.GRTEMPLATE = params->SBRTEMPLATE;
rparams.reference = IBO;
rparams.DX = (RDW >> 1) + RDX;
rparams.DY = (RDH >> 1) + RDY;
rparams.TPGRON = 0;
memcpy(rparams.grat, params->sbrat, 4);
jbig2_decode_refinement_region(ctx, segment,
&rparams, as, refimage, GR_stats);
IB = refimage;
jbig2_image_release(ctx, IBO);
/* 6.4.11 (7) */
if (params->SBHUFF) {
jbig2_huffman_advance(hs, BMSIZE);
}
}
/* (3c.vi) */
if ((!params->TRANSPOSED) && (params->REFCORNER > 1)) {
CURS += IB->width - 1;
} else if ((params->TRANSPOSED) && !(params->REFCORNER & 1)) {
CURS += IB->height - 1;
}
/* (3c.vii) */
S = CURS;
/* (3c.viii) */
if (!params->TRANSPOSED) {
switch (params->REFCORNER) {
case JBIG2_CORNER_TOPLEFT: x = S; y = T; break;
case JBIG2_CORNER_TOPRIGHT: x = S - IB->width + 1; y = T; break;
case JBIG2_CORNER_BOTTOMLEFT: x = S; y = T - IB->height + 1; break;
case JBIG2_CORNER_BOTTOMRIGHT: x = S - IB->width + 1; y = T - IB->height + 1; break;
}
} else { /* TRANSPOSED */
switch (params->REFCORNER) {
case JBIG2_CORNER_TOPLEFT: x = T; y = S; break;
case JBIG2_CORNER_TOPRIGHT: x = T - IB->width + 1; y = S; break;
case JBIG2_CORNER_BOTTOMLEFT: x = T; y = S - IB->height + 1; break;
case JBIG2_CORNER_BOTTOMRIGHT: x = T - IB->width + 1; y = S - IB->height + 1; break;
}
}
/* (3c.ix) */
#ifdef JBIG2_DEBUG
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number,
"composing glyph id %d: %dx%d @ (%d,%d) symbol %d/%d",
ID, IB->width, IB->height, x, y, NINSTANCES + 1,
params->SBNUMINSTANCES);
#endif
jbig2_image_compose(ctx, image, IB, x, y, params->SBCOMBOP);
/* (3c.x) */
if ((!params->TRANSPOSED) && (params->REFCORNER < 2)) {
CURS += IB->width -1 ;
} else if ((params->TRANSPOSED) && (params->REFCORNER & 1)) {
CURS += IB->height - 1;
}
/* (3c.xi) */
NINSTANCES++;
jbig2_image_release(ctx, IB);
}
/* end strip */
}
/* 6.4.5 (4) */
cleanup2:
if (params->SBHUFF) {
jbig2_release_huffman_table(ctx, SBSYMCODES);
}
jbig2_huffman_free(ctx, hs);
return code;
}
