ref: bfea189549eccb3a6f1a81bbd1bbb092ab789b35
dir: /jbig2_segment.c/
/*
jbig2dec
Copyright (c) 2002-2003 artofcode LLC.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
$Id: jbig2_segment.c,v 1.23 2003/03/10 14:44:01 giles Exp $
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "os_types.h"
#include <stddef.h> /* size_t */
#include "jbig2.h"
#include "jbig2_priv.h"
#include "jbig2_symbol_dict.h"
Jbig2Segment *
jbig2_parse_segment_header (Jbig2Ctx *ctx, uint8_t *buf, size_t buf_size,
size_t *p_header_size)
{
Jbig2Segment *result;
uint8_t rtscarf;
uint32_t rtscarf_long;
uint32_t *referred_to_segments;
int referred_to_segment_count;
int referred_to_segment_size;
int pa_size;
int offset;
/* minimum possible size of a jbig2 segment header */
if (buf_size < 11)
return NULL;
result = (Jbig2Segment *)jbig2_alloc(ctx->allocator,
sizeof(Jbig2Segment));
/* 7.2.2 */
result->number = jbig2_get_int32(buf);
/* 7.2.3 */
result->flags = buf[4];
/* 7.2.4 referred-to segments */
rtscarf = buf[5];
if ((rtscarf & 0xe0) == 0xe0)
{
rtscarf_long = jbig2_get_int32(buf + 5);
referred_to_segment_count = rtscarf_long & 0x1fffffff;
offset = 5 + 4 + (referred_to_segment_count + 1) / 8;
}
else
{
referred_to_segment_count = (rtscarf >> 5);
offset = 5 + 1;
}
result->referred_to_segment_count = referred_to_segment_count;
/* we now have enough information to compute the full header length */
referred_to_segment_size = result->number <= 256 ? 1:
result->number <= 65536 ? 2 : 4; /* 7.2.5 */
pa_size = result->flags & 0x40 ? 4 : 1; /* 7.2.6 */
if (offset + referred_to_segment_count*referred_to_segment_size + pa_size + 4 > buf_size)
{
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, result->number,
"jbig2_parse_segment_header() called with insufficient data", -1);
jbig2_free (ctx->allocator, result);
return NULL;
}
/* 7.2.5 */
if (referred_to_segment_count)
{
int i;
referred_to_segments = jbig2_alloc(ctx->allocator, referred_to_segment_count * referred_to_segment_size * sizeof(uint32_t));
for (i = 0; i < referred_to_segment_count; i++) {
referred_to_segments[i] =
(referred_to_segment_size == 1) ? buf[offset] :
(referred_to_segment_size == 2) ? jbig2_get_int16(buf+offset) :
jbig2_get_int32(buf + offset);
offset += referred_to_segment_size;
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, result->number,
"segment %d refers to segment %d",
result->number, referred_to_segments[i]);
}
result->referred_to_segments = referred_to_segments;
}
else /* no referred-to segments */
{
result->referred_to_segments = NULL;
}
/* 7.2.6 */
if (result->flags & 0x40) {
result->page_association = jbig2_get_int32(buf + offset);
offset += 4;
} else {
result->page_association = buf[offset++];
}
jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, result->number,
"segment %d is associated with page %d",
result->number, result->page_association);
/* 7.2.7 */
result->data_length = jbig2_get_int32(buf + offset);
*p_header_size = offset + 4;
return result;
}
void
jbig2_free_segment (Jbig2Ctx *ctx, Jbig2Segment *segment)
{
if (segment->referred_to_segments != NULL) {
jbig2_free(ctx->allocator, segment->referred_to_segments);
}
/* todo: free result */
jbig2_free (ctx->allocator, segment);
}
/* find a segment by number */
Jbig2Segment *
jbig2_find_segment(Jbig2Ctx *ctx, uint32_t number)
{
int index, index_max = ctx->segment_index - 1;
const Jbig2Ctx *global_ctx = ctx->global_ctx;
/* FIXME: binary search would be better */
for (index = index_max; index >= 0; index--)
if (ctx->segments[index]->number == number)
return (ctx->segments[index]);
if (global_ctx)
for (index = global_ctx->segment_index - 1; index >= 0; index--)
if (global_ctx->segments[index]->number == number)
return (global_ctx->segments[index]);
/* didn't find a match */
return NULL;
}
/* parse the generic portion of a region segment data header */
void
jbig2_get_region_segment_info(Jbig2RegionSegmentInfo *info,
const byte *segment_data)
{
/* 7.4.1 */
info->width = jbig2_get_int32(segment_data);
info->height = jbig2_get_int32(segment_data + 4);
info->x = jbig2_get_int32(segment_data + 8);
info->y = jbig2_get_int32(segment_data + 12);
info->flags = segment_data[16];
}
/* dispatch code for extension segment parsing */
int jbig2_parse_extension_segment(Jbig2Ctx *ctx, Jbig2Segment *segment,
const uint8_t *segment_data)
{
uint32_t type;
bool reserved, dependent, necessary;
type = jbig2_get_int32(segment_data);
reserved = type & 0x20000000;
dependent = type & 0x40000000;
necessary = type & 0x80000000;
if (necessary && !reserved) {
jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"extension segment is marked 'necessary' but not 'reservered' contrary to spec");
}
switch (type) {
case 0x20000000: return jbig2_parse_comment_ascii(ctx, segment, segment_data);
case 0x20000002: return jbig2_parse_comment_unicode(ctx, segment, segment_data);
default:
if (necessary) {
return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number,
"unhandled necessary extension segment type 0x%08x", type);
} else {
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled extension segment");
}
}
return 0;
}
/* general segment parsing dispatch */
int jbig2_parse_segment (Jbig2Ctx *ctx, Jbig2Segment *segment,
const uint8_t *segment_data)
{
jbig2_error(ctx, JBIG2_SEVERITY_INFO, segment->number,
"Segment %d, flags=%x, type=%d, data_length=%d",
segment->number, segment->flags, segment->flags & 63,
segment->data_length);
switch (segment->flags & 63)
{
case 0:
return jbig2_symbol_dictionary(ctx, segment, segment_data);
case 4: /* intermediate text region */
case 6: /* immediate text region */
case 7: /* immediate lossless text region */
return jbig2_parse_text_region(ctx, segment, segment_data);
case 16:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'pattern dictionary'");
case 20:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'intermediate halftone region'");
case 22:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'immediate halftone region'");
case 23:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'immediate lossless halftone region'");
case 36:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'intermediate generic region'");
case 38:
return jbig2_immediate_generic_region(ctx, segment, segment_data);
case 39:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'immediate lossless generic region'");
case 40:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'intermediate generic refinement region'");
case 42:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'immediate generic refinement region'");
case 43:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'immediate lossless generic refinement region'");
case 48:
return jbig2_parse_page_info(ctx, segment, segment_data);
case 49:
return jbig2_parse_end_of_page(ctx, segment, segment_data);
case 50:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'end of stripe'");
case 51:
ctx->state = JBIG2_FILE_EOF;
return jbig2_error(ctx, JBIG2_SEVERITY_INFO, segment->number,
"end of file");
case 52:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled segment type 'profile'");
case 53:
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unhandled table segment");
case 62:
return jbig2_parse_extension_segment(ctx, segment, segment_data);
default:
jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"unknown segment type %d", segment->flags & 63);
}
return 0;
}