shithub: jbig2

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Work around missing end-of-page segment in CVision's PDF-embedded jbig2 streams.
jbig2_complete_page() becomes a public function marking the current page finished
so the client can call it at end-of-data, since data-shovel interface has no way
of passing that out-of-band. The segment dispatch calls a new jbig2_parse_end_of_page()
which does error checking and then calls jbig2_complete_page().


git-svn-id: http://svn.ghostscript.com/jbig2dec/trunk@126 ded80894-8fb9-0310-811b-c03f3676ab4d

--- a/jbig2.h

+++ b/jbig2.h

@@ -8,7 +8,7 @@

     the Free Software Foundation; either version 2 of the License, or

     (at your option) any later version.

-    $Id: jbig2.h,v 1.13 2002/07/08 14:26:02 giles Exp $

+    $Id: jbig2.h,v 1.14 2002/07/09 09:45:32 giles Exp $

 */

 #ifdef __cplusplus

@@ -85,6 +85,9 @@

 Jbig2Image *jbig2_page_out (Jbig2Ctx *ctx);

 /* mark a returned page image as read */

 int jbig2_release_page (Jbig2Ctx *ctx, Jbig2Image *image);

+/* mark the current page as complete, regardless of decoder state (for broken streams) */

+int jbig2_complete_page (Jbig2Ctx *ctx);

+

 /* segment header routines */

--- a/jbig2_page.c

+++ b/jbig2_page.c

@@ -8,7 +8,7 @@

     the Free Software Foundation; either version 2 of the License, or

     (at your option) any later version.

-    $Id: jbig2_page.c,v 1.11 2002/07/08 14:54:01 giles Exp $

+    $Id: jbig2_page.c,v 1.12 2002/07/09 09:45:32 giles Exp $

 */

 #ifdef HAVE_CONFIG_H

@@ -167,10 +167,23 @@

  * of the page image will also happen from here (NYI)

  **/

 int

-jbig2_complete_page (Jbig2Ctx *ctx, Jbig2Segment *segment, const byte *segment_data)

+jbig2_complete_page (Jbig2Ctx *ctx)

 {

     uint32_t page_number = ctx->pages[ctx->current_page].number;

-    

+        

+    ctx->pages[ctx->current_page].state = JBIG2_PAGE_COMPLETE;

+

+    return 0;

+}

+

+/**

+ * jbig2_parse_end_of_page: parse an end of page segment

+ **/

+int

+jbig2_parse_end_of_page(Jbig2Ctx *ctx, Jbig2Segment *segment, const byte *segment_data)

+{

+    uint32_t page_number = ctx->pages[ctx->current_page].number;

+

     if (segment->page_association != page_number) {

         jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,

             "end of page marker for page %d doesn't match current page number %d",

@@ -177,10 +190,11 @@

             segment->page_association, page_number);

     }

-    ctx->pages[ctx->current_page].state = JBIG2_PAGE_COMPLETE;

     jbig2_error(ctx, JBIG2_SEVERITY_INFO, segment->number,

         "end of page %d", page_number);

+    jbig2_complete_page(ctx);

+    

 #ifdef OUTPUT_PBM

     jbig2_image_write_pbm(ctx->pages[ctx->current_page].image, stdout);

 #endif

@@ -228,6 +242,7 @@

     /* find the matching page struct and mark it released */

     for (index = 0; index < ctx->max_page_index; index++) {

         if (ctx->pages[index].image == image) {

+            /* todo: free associated image */

             ctx->pages[index].state = JBIG2_PAGE_RELEASED;

             jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, -1,

                 "page %d released by the client", ctx->pages[index].number);

--- a/jbig2_priv.h

+++ b/jbig2_priv.h

@@ -8,7 +8,7 @@

     the Free Software Foundation; either version 2 of the License, or

     (at your option) any later version.

-    $Id: jbig2_priv.h,v 1.13 2002/07/08 19:23:11 giles Exp $

+    $Id: jbig2_priv.h,v 1.14 2002/07/09 09:45:32 giles Exp $

     shared library internals

 */

@@ -111,7 +111,7 @@

 };

 int jbig2_parse_page_info (Jbig2Ctx *ctx, Jbig2Segment *segment, const byte *segment_data);

-int jbig2_complete_page (Jbig2Ctx *ctx, Jbig2Segment *segment, const byte *segment_data);

+int jbig2_parse_end_of_page(Jbig2Ctx *ctx, Jbig2Segment *segment, const byte *segment_data);

 typedef enum {

     JBIG2_COMPOSE_OR = 0,

--- 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 1.16 2002/07/08 19:23:11 giles Exp $

+    $Id: jbig2_segment.c,v 1.17 2002/07/09 09:45:32 giles Exp $

 */

 #ifdef HAVE_CONFIG_H

@@ -84,7 +84,8 @@

             jbig2_get_int32(buf + offset);

         offset += referred_to_segment_size;

         jbig2_error(ctx, JBIG2_SEVERITY_DEBUG, result->number,

-            "refers to segment %d", referred_to_segments[i]);

+            "segment %d refers to segment %d",

+            result->number, ctx->segments[referred_to_segments[i]]->number);

       }

       result->referred_to_segments = referred_to_segments;

     }

@@ -185,7 +186,7 @@

     case 48:

       return jbig2_parse_page_info(ctx, segment, segment_data);

     case 49:

-      return jbig2_complete_page(ctx, segment, segment_data);

+      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'");

--- a/jbig2dec.c

+++ b/jbig2dec.c

@@ -8,7 +8,7 @@

     the Free Software Foundation; either version 2 of the License, or

     (at your option) any later version.

-    $Id: jbig2dec.c,v 1.28 2002/07/08 14:54:02 giles Exp $

+    $Id: jbig2dec.c,v 1.29 2002/07/09 09:45:32 giles Exp $

 */

 #ifdef HAVE_CONFIG_H

@@ -259,6 +259,11 @@

   {

     Jbig2Image *image;

+    /* work around broken CVision embedded streams */

+    if (f_page != NULL)

+      jbig2_complete_page(ctx);

+    

+    /* retrieve and write out all the completed pages */

     while ((image = jbig2_page_out(ctx)) != NULL) {

       write_page_image(&params, image);

       jbig2_release_page(ctx, image);