ref: 5219d82fa11b750c446a1d00d2bc269cea245610
parent: dcb620344060d47d77e620d23c0e3e6aa3838f6b
author: giles <giles@ded80894-8fb9-0310-811b-c03f3676ab4d>
date: Mon Jun 17 17:06:38 EDT 2002
Further segment code rearrangement. Add some comments and promote some bitwise types to unsigned. Also add some diagnostic messages on segment type. git-svn-id: http://svn.ghostscript.com/jbig2dec/trunk@69 ded80894-8fb9-0310-811b-c03f3676ab4d
--- a/jbig2.c
+++ b/jbig2.c
@@ -8,7 +8,7 @@
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
- $Id: jbig2.c,v 1.6 2002/06/15 14:12:50 giles Exp $
+ $Id: jbig2.c,v 1.7 2002/06/17 21:06:38 giles Exp $
*/
#include <stdint.h>
@@ -133,83 +133,18 @@
return (buf[0] << 8) | buf[1];
}
-static Jbig2SegmentHeader *
-jbig2_parse_segment_header (Jbig2Ctx *ctx, uint8_t *buf, size_t buf_size,
- size_t *p_header_size)
-{- Jbig2SegmentHeader *result;
- byte rtscarf;
- int32_t rtscarf_long;
- 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 = (Jbig2SegmentHeader *)jbig2_alloc(ctx->allocator,
- sizeof(Jbig2SegmentHeader));
-
- /* 7.2.2 */
- result->segment_number = jbig2_get_int32 (buf);
-
- /* 7.2.3 */
- result->flags = buf[4];
-
- /* 7.2.4 */
- 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;
-
- /* 7.2.5 */
- /* todo: read referred to segment numbers */
- /* For now, we skip them. */
- referred_to_segment_size = result->segment_number <= 256 ? 1:
- result->segment_number <= 65536 ? 2:
- 4;
- offset += referred_to_segment_count * referred_to_segment_size;
-
- /* 7.2.6 */
- pa_size = result->flags & 0x40 ? 4 : 1;
-
- if (offset + pa_size + 4 > buf_size)
- {- jbig2_free (ctx->allocator, result);
- return NULL;
- }
-
- if (result->flags & 0x40) {- result->page_association = jbig2_get_int32(buf + offset);
- offset += 4;
- } else {- result->page_association = buf[offset++];
- }
-
- /* 7.2.7 */
- result->data_length = jbig2_get_int32 (buf + offset);
- *p_header_size = offset + 4;
-
- return result;
-}
-
-void
-jbig2_free_segment_header (Jbig2Ctx *ctx, Jbig2SegmentHeader *sh)
-{- jbig2_free (ctx->allocator, sh);
-}
-
+/**
+ * jbig2_write: submit data for decoding
+ * @ctx: The jbig2dec decoder context
+ * @data: a pointer to the data buffer
+ * @size: the size of the data buffer in bytes
+ *
+ * Copies the specified data into internal storage and attempts
+ * to (continue to) parse it as part of a jbig2 data stream.
+ *
+ * Return code: 0 on success
+ **/
int
jbig2_write (Jbig2Ctx *ctx, const unsigned char *data, size_t size)
{@@ -231,7 +166,7 @@
{if (ctx->buf_rd_ix <= (ctx->buf_size >> 1) &&
ctx->buf_wr_ix - ctx->buf_rd_ix + size <= ctx->buf_size)
- {+ {memcpy (ctx->buf, ctx->buf + ctx->buf_rd_ix,
ctx->buf_wr_ix - ctx->buf_rd_ix);
}
@@ -268,21 +203,26 @@
switch (ctx->state)
{case JBIG2_FILE_HEADER:
+ /* D.4.1 */
if (ctx->buf_wr_ix - ctx->buf_rd_ix < 9)
return 0;
if (memcmp(ctx->buf + ctx->buf_rd_ix, jbig2_id_string, 8))
return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, -1,
"Not a JBIG2 file header");
+ /* D.4.2 */
ctx->file_header_flags = ctx->buf[ctx->buf_rd_ix + 8];
+ /* D.4.3 */
if (!(ctx->file_header_flags & 2))
{if (ctx->buf_wr_ix - ctx->buf_rd_ix < 13)
return 0;
ctx->n_pages = jbig2_get_int32(ctx->buf + ctx->buf_rd_ix + 9);
+ jbig2_error(ctx, JBIG2_SEVERITY_INFO, -1, "file header indicates %d pages", ctx->n_pages);
ctx->buf_rd_ix += 13;
}
else
ctx->buf_rd_ix += 9;
+ /* determine the file organization based on the flags - D.4.2 again */
if (ctx->file_header_flags & 1)
{ctx->state = JBIG2_FILE_SEQUENTIAL_HEADER;
@@ -318,7 +258,7 @@
if ((sh->flags & 63) == 51) /* end of file */
ctx->state = JBIG2_FILE_RANDOM_BODIES;
}
- else
+ else /* JBIG2_FILE_SEQUENTIAL_HEADER */
ctx->state = JBIG2_FILE_SEQUENTIAL_BODY;
break;
case JBIG2_FILE_SEQUENTIAL_BODY:
@@ -336,7 +276,7 @@
if (ctx->sh_ix == ctx->n_sh)
ctx->state = JBIG2_FILE_EOF;
}
- else
+ else /* JBIG2_FILE_SEQUENCIAL_BODY */
{ctx->n_sh = 0;
ctx->state = JBIG2_FILE_SEQUENTIAL_HEADER;
@@ -357,14 +297,12 @@
return 0;
}
-/* get_bits */
-
void
jbig2_ctx_free (Jbig2Ctx *ctx)
{Jbig2Allocator *ca = ctx->allocator;
int i;
- int32_t seg_ix;
+ uint32_t seg_ix;
jbig2_free(ca, ctx->buf);
if (ctx->sh_list != NULL)
--- a/jbig2_segment.c
+++ b/jbig2_segment.c
@@ -8,7 +8,7 @@
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
- $Id: jbig2_segment.c,v 1.1 2002/06/15 16:16:20 giles Exp $
+ $Id: jbig2_segment.c,v 1.2 2002/06/17 21:06:38 giles Exp $
*/
#include <stdio.h>
@@ -19,6 +19,83 @@
#include "jbig2_priv.h"
#include "jbig2_symbol_dict.h"
+Jbig2SegmentHeader *
+jbig2_parse_segment_header (Jbig2Ctx *ctx, uint8_t *buf, size_t buf_size,
+ size_t *p_header_size)
+{+ Jbig2SegmentHeader *result;
+ uint8_t rtscarf;
+ uint32_t rtscarf_long;
+ 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 = (Jbig2SegmentHeader *)jbig2_alloc(ctx->allocator,
+ sizeof(Jbig2SegmentHeader));
+
+ /* 7.2.2 */
+ result->segment_number = jbig2_get_int32 (buf);
+
+ /* 7.2.3 */
+ result->flags = buf[4];
+
+ /* 7.2.4 */
+ 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;
+
+ /* 7.2.5 */
+ /* todo: read referred to segment numbers */
+ /* For now, we skip them. */
+ referred_to_segment_size = result->segment_number <= 256 ? 1:
+ result->segment_number <= 65536 ? 2:
+ 4;
+ offset += referred_to_segment_count * referred_to_segment_size;
+
+ /* 7.2.6 */
+ pa_size = result->flags & 0x40 ? 4 : 1;
+
+ if (offset + pa_size + 4 > buf_size)
+ {+ jbig2_free (ctx->allocator, result);
+ return NULL;
+ }
+
+ if (result->flags & 0x40) {+ result->page_association = jbig2_get_int32(buf + offset);
+ offset += 4;
+ } else {+ result->page_association = buf[offset++];
+ }
+
+ /* 7.2.7 */
+ result->data_length = jbig2_get_int32 (buf + offset);
+ *p_header_size = offset + 4;
+
+ return result;
+}
+
+void
+jbig2_free_segment_header (Jbig2Ctx *ctx, Jbig2SegmentHeader *sh)
+{+ jbig2_free (ctx->allocator, sh);
+}
+
int jbig2_write_segment (Jbig2Ctx *ctx, Jbig2SegmentHeader *sh,
const uint8_t *segment_data)
{@@ -32,6 +109,37 @@
return jbig2_symbol_dictionary(ctx, sh, segment_data);
case 38:
return jbig2_immediate_generic_region(ctx, sh, segment_data);
+ case 48:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unhandled segment type 'page info'");
+ break;
+ case 49:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unhandled segment type 'end of page'");
+ break;
+ case 50:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unhandled segment type 'end of stripe'");
+ break;
+ case 51:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unhandled segment type 'end of file'");
+ break;
+ case 52:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unhandled segment type 'profile'");
+ break;
+ case 53:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unhandled table segment");
+ break;
+ case 62:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unhandled extension segment");
+ break;
+ default:
+ jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+ "unknown segment type %d", sh->flags & 63);
}
return 0;
}