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jbig2dec: Check for T.88 amendments 2/3 bitstreams.

T.88 Amendment 2 adds up to 12 adaptive template pixels in generic regions.
T.88 Amendment 3 adds support for generic/text regions to encode colors.
Neither amendment is implemented and no sample files have been found.
Return fatal errors for such bitstreams/files for the time being.

--- a/jbig2.c

+++ b/jbig2.c

@@ -256,6 +256,12 @@

                 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];

+            /* Check for T.88 amendment 2 */

+            if (ctx->file_header_flags & 0x04)

+                return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, -1, "file header indicates use of 12 adaptive template pixels (NYI)");

+            /* Check for T.88 amendment 3 */

+            if (ctx->file_header_flags & 0x08)

+                return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, -1, "file header indicates use of colored region segments (NYI)");

             if (ctx->file_header_flags & 0xFC) {

                 jbig2_error(ctx, JBIG2_SEVERITY_WARNING, -1, "reserved bits (2-7) of file header flags are not zero (0x%02x)", ctx->file_header_flags);

             }

--- a/jbig2_generic.c

+++ b/jbig2_generic.c

@@ -806,6 +806,10 @@

     offset = 18 + gbat_bytes;

+    /* Check for T.88 amendment 2 */

+    if ((seg_flags >> 5) & 1)

+        return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number, "segment uses 12 adaptive template pixels (NYI)");

+

     /* Table 34 */

     params.MMR = seg_flags & 1;

     params.GBTEMPLATE = (seg_flags & 6) >> 1;

--- a/jbig2_page.c

+++ b/jbig2_page.c

@@ -109,6 +109,9 @@

     page->x_resolution = jbig2_get_uint32(segment_data + 8);

     page->y_resolution = jbig2_get_uint32(segment_data + 12);

     page->flags = segment_data[16];

+    /* Check for T.88 amendment 3 */

+    if (page->flags & 0x80)

+        return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number, "page segment indicates use of color segments (NYI)");

     /* 7.4.8.6 */

     {

--- a/jbig2_segment.c

+++ b/jbig2_segment.c

@@ -282,6 +282,8 @@

         return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number, "unhandled segment type 'profile'");

     case 53:                   /* user-supplied huffman table */

         return jbig2_table(ctx, segment, segment_data);

+    case 54:

+        return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number, "unhandled segment type 'color palette'");

     case 62:

         return jbig2_parse_extension_segment(ctx, segment, segment_data);

     default:

--- a/jbig2_text.c

+++ b/jbig2_text.c

@@ -579,6 +579,9 @@

         goto too_short;

     jbig2_get_region_segment_info(&region_info, segment_data);

     offset += 17;

+    /* Check for T.88 amendment 3 */

+    if (region_info.flags & 8)

+        return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number, "region segment flags indicate use of colored bitmap (NYI)");

     /* 7.4.3.1.1 */

     if (segment->data_length - offset < 2)