ref: d2d97abc0be98770dc506620f5f8921900e55e5e
parent: a0531af83d6d29abe2fccb488fa7b741d68cb3fd
author: giles <giles@ded80894-8fb9-0310-811b-c03f3676ab4d>
date: Tue Aug 23 02:09:55 EDT 2005
Work-in-progress commit of huffman text region support. Initial implemetation of symbol id huffman table decode. git-svn-id: http://svn.ghostscript.com/jbig2dec/trunk@431 ded80894-8fb9-0310-811b-c03f3676ab4d
--- a/jbig2_text.c
+++ b/jbig2_text.c
@@ -54,7 +54,7 @@
int LOGSBSTRIPS;
int SBSTRIPS;
/* SBNUMSYMS */
- Jbig2HuffmanTable *SBSYMCODES;
+ /* SBSYMCODES */
/* SBSYMCODELEN */
/* SBSYMS */
Jbig2HuffmanTable *SBHUFFFS;
@@ -108,10 +108,11 @@
int S,T;
int x,y;
bool first_symbol;
- uint32_t index, max_id;
+ uint32_t index, SBNUMSYMS;
Jbig2Image *IB;
Jbig2WordStream *ws = NULL;
Jbig2HuffmanState *hs = NULL;
+ Jbig2HuffmanTable *SBSYMCODES;
Jbig2ArithState *as = NULL;
Jbig2ArithIntCtx *IADT = NULL;
Jbig2ArithIntCtx *IAFS = NULL;
@@ -126,12 +127,12 @@
int code = 0;
int RI;
- max_id = 0;
+ SBNUMSYMS = 0;
for (index = 0; index < n_dicts; index++) {- max_id += dicts[index]->n_symbols;
+ SBNUMSYMS += dicts[index]->n_symbols;
}
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number,
- "symbol list contains %d glyphs in %d dictionaries", max_id, n_dicts);
+ "symbol list contains %d glyphs in %d dictionaries", SBNUMSYMS, n_dicts);
ws = jbig2_word_stream_buf_new(ctx, data, size);
if (!params->SBHUFF) {@@ -143,7 +144,7 @@
IADS = jbig2_arith_int_ctx_new(ctx);
IAIT = jbig2_arith_int_ctx_new(ctx);
/* Table 31 */
- for (SBSYMCODELEN = 0; (1 << SBSYMCODELEN) < max_id; SBSYMCODELEN++);
+ for (SBSYMCODELEN = 0; (1 << SBSYMCODELEN) < SBNUMSYMS; SBSYMCODELEN++);
IAID = jbig2_arith_iaid_ctx_new(ctx, SBSYMCODELEN);
IARI = jbig2_arith_int_ctx_new(ctx);
IARDW = jbig2_arith_int_ctx_new(ctx);
@@ -151,9 +152,82 @@
IARDX = jbig2_arith_int_ctx_new(ctx);
IARDY = jbig2_arith_int_ctx_new(ctx);
} else {+ Jbig2HuffmanTable *runcodes;
+ Jbig2HuffmanParams runcodeparams;
+ Jbig2HuffmanLine runcodelengths[35];
+ Jbig2HuffmanLine *symcodelengths;
+ Jbig2HuffmanParams symcodeparams;
+ int code, err, range, r;
+
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, segment->number,
"huffman coded text region");
hs = jbig2_huffman_new(ctx, ws);
+
+ /* 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]);
+ }
+ 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!");
+ return -1;
+ }
+
+ /* decode the symbol id codelengths using the runlength table */
+ symcodelengths = jbig2_alloc(ctx->allocator, SBNUMSYMS*sizeof(Jbig2HuffmanLine));
+ /* todo: could save considerable space by growing the lines array as needed */
+ if (symcodelengths == NULL) {+ jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
+ "memory allocation failure reading symbol ID huffman table!");
+ return -1;
+ }
+ for (index = 0; index < SBNUMSYMS; index++) {+ 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!");
+ return err;
+ }
+
+ if (code < 32) range = 0;
+ else if (code == 32) range = jbig2_huffman_get_bits(hs, 2);
+ else if (code == 34) range = jbig2_huffman_get_bits(hs, 3);
+ else if (code == 35) range = jbig2_huffman_get_bits(hs, 7);
+ for (r = 0; r < range + 1; r++) {+ symcodelengths[index+r].PREFLEN = code;
+ symcodelengths[index+r].RANGELEN = 0;
+ symcodelengths[index+r].RANGELOW = index;
+ }
+ index += r;
+ if (index > SBNUMSYMS) {+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
+ "runlength extends beyond the end of symbol id table");
+ }
+ }
+ 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);
+
+ jbig2_free(ctx->allocator, symcodelengths);
+ jbig2_release_huffman_table(ctx, runcodes);
}
/* 6.4.5 (1) */
@@ -222,13 +296,13 @@
/* (3b.iv) / 6.4.10 - decode the symbol id */
if (params->SBHUFF) {- ID = jbig2_huffman_get(hs, params->SBSYMCODES, &code);
+ ID = jbig2_huffman_get(hs, SBSYMCODES, &code);
} else {code = jbig2_arith_iaid_decode(IAID, as, (int *)&ID);
}
- if (ID >= max_id) {+ if (ID >= SBNUMSYMS) {return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
- "symbol id out of range! (%d/%d)", ID, max_id);
+ "symbol id out of range! (%d/%d)", ID, SBNUMSYMS);
}
/* (3c.v) / 6.4.11 - look up the symbol bitmap IB */
@@ -348,7 +422,9 @@
}
/* 6.4.5 (4) */
- if (!params->SBHUFF) {+ if (params->SBHUFF) {+ jbig2_release_huffman_table(ctx, SBSYMCODES);
+ } else {jbig2_arith_int_ctx_free(ctx, IADT);
jbig2_arith_int_ctx_free(ctx, IAFS);
jbig2_arith_int_ctx_free(ctx, IADS);
@@ -592,7 +668,7 @@
}
/* 7.4.3.1.7 */
- /* todo: symbol ID huffman table decoding */
+ /* For convenience this is done in the body decoder routine */
}
jbig2_error(ctx, JBIG2_SEVERITY_INFO, segment->number,