Keep JBIG2 image data compressed in fz_compressed_buffer.

5 files changed, 43 insertions, 15 deletions

diff --git a/include/mupdf/fitz/compressed-buffer.h b/include/mupdf/fitz/compressed-buffer.h
index 995f5606..0078e955 100644
--- a/include/mupdf/fitz/compressed-buffer.h
+++ b/include/mupdf/fitz/compressed-buffer.h
@@ -5,6 +5,7 @@
 #include "mupdf/fitz/context.h"
 #include "mupdf/fitz/buffer.h"
 #include "mupdf/fitz/stream.h"
+#include "mupdf/fitz/filter.h"
 
 typedef struct fz_compression_params_s fz_compression_params;
 
@@ -33,6 +34,7 @@ enum
 	/* Full image formats */
 	FZ_IMAGE_BMP,
 	FZ_IMAGE_GIF,
+	FZ_IMAGE_JBIG2,
 	FZ_IMAGE_JPEG,
 	FZ_IMAGE_JPX,
 	FZ_IMAGE_JXR,
@@ -52,6 +54,9 @@ struct fz_compression_params_s
 			int smask_in_data;
 		} jpx;
 		struct {
+			fz_jbig2_globals *globals;
+		} jbig2;
+		struct {
 			int columns;
 			int rows;
 			int k;
diff --git a/include/mupdf/fitz/filter.h b/include/mupdf/fitz/filter.h
index 495b960e..a570dd71 100644
--- a/include/mupdf/fitz/filter.h
+++ b/include/mupdf/fitz/filter.h
@@ -34,6 +34,8 @@ fz_stream *fz_open_predict(fz_context *ctx, fz_stream *chain, int predictor, int
 fz_stream *fz_open_jbig2d(fz_context *ctx, fz_stream *chain, fz_jbig2_globals *globals);
 
 fz_jbig2_globals *fz_load_jbig2_globals(fz_context *ctx, fz_buffer *buf);
+fz_jbig2_globals *fz_keep_jbig2_globals(fz_context *ctx, fz_jbig2_globals *globals);
+void fz_drop_jbig2_globals(fz_context *ctx, fz_jbig2_globals *globals);
 void fz_drop_jbig2_globals_imp(fz_context *ctx, fz_storable *globals);
 
 /* Extra filters for tiff */
diff --git a/source/fitz/compressed-buffer.c b/source/fitz/compressed-buffer.c
index e8ea08e0..35b0868b 100644
--- a/source/fitz/compressed-buffer.c
+++ b/source/fitz/compressed-buffer.c
@@ -8,6 +8,8 @@ fz_drop_compressed_buffer(fz_context *ctx, fz_compressed_buffer *buf)
 {
 	if (buf)
 	{
+		if (buf->params.type == FZ_IMAGE_JBIG2)
+			fz_drop_jbig2_globals(ctx, buf->params.u.jbig2.globals);
 		fz_drop_buffer(ctx, buf->buffer);
 		fz_free(ctx, buf);
 	}
@@ -66,6 +68,10 @@ fz_open_image_decomp_stream(fz_context *ctx, fz_stream *tail, fz_compression_par
 			head = fz_open_dctd(ctx, tail, params->u.jpeg.color_transform, our_l2factor, NULL);
 			break;
 
+		case FZ_IMAGE_JBIG2:
+			head = fz_open_jbig2d(ctx, tail, fz_keep_jbig2_globals(ctx, params->u.jbig2.globals));
+			break;
+
 		case FZ_IMAGE_RLD:
 			head = fz_open_rld(ctx, tail);
 			break;
diff --git a/source/fitz/filter-jbig2.c b/source/fitz/filter-jbig2.c
index 0d581b95..599f94c0 100644
--- a/source/fitz/filter-jbig2.c
+++ b/source/fitz/filter-jbig2.c
@@ -28,7 +28,13 @@ struct fz_jbig2d_s
 	int idx;
 };
 
-static void
+fz_jbig2_globals *
+fz_keep_jbig2_globals(fz_context *ctx, fz_jbig2_globals *globals)
+{
+	return fz_keep_storable(ctx, &globals->storable);
+}
+
+void
 fz_drop_jbig2_globals(fz_context *ctx, fz_jbig2_globals *globals)
 {
 	fz_drop_storable(ctx, &globals->storable);
@@ -268,7 +274,13 @@ struct fz_jbig2d_s
 	unsigned char buffer[4096];
 };
 
-static void
+fz_jbig2_globals *
+fz_keep_jbig2_globals(fz_context *ctx, fz_jbig2_globals *globals)
+{
+	return fz_keep_storable(ctx, &globals->storable);
+}
+
+void
 fz_drop_jbig2_globals(fz_context *ctx, fz_jbig2_globals *globals)
 {
 	fz_drop_storable(ctx, &globals->storable);
diff --git a/source/pdf/pdf-stream.c b/source/pdf/pdf-stream.c
index 839f9b5e..04f1ed46 100644
--- a/source/pdf/pdf-stream.c
+++ b/source/pdf/pdf-stream.c
@@ -58,7 +58,7 @@ pdf_stream_has_crypt(fz_context *ctx, pdf_obj *stm)
 }
 
 static fz_jbig2_globals *
-pdf_load_jbig2_globals(fz_context *ctx, pdf_document *doc, pdf_obj *dict)
+pdf_load_jbig2_globals(fz_context *ctx, pdf_obj *dict)
 {
 	fz_jbig2_globals *globals;
 	fz_buffer *buf = NULL;
@@ -149,6 +149,20 @@ build_compression_params(fz_context *ctx, pdf_obj *f, pdf_obj *p, fz_compression
 		params->u.lzw.bpc = bpc;
 		params->u.lzw.early_change = (ec ? pdf_to_int(ctx, ec) : 1);
 	}
+	else if (pdf_name_eq(ctx, f, PDF_NAME(JBIG2Decode)))
+	{
+		pdf_obj *g = pdf_dict_get(ctx, p, PDF_NAME(JBIG2Globals));
+
+		params->type = FZ_IMAGE_JBIG2;
+		params->u.jbig2.globals = NULL;
+		if (g)
+		{
+			if (!pdf_is_stream(ctx, g))
+				fz_warn(ctx, "jbig2 globals is not a stream, skipping globals");
+			else
+				params->u.jbig2.globals = pdf_load_jbig2_globals(ctx, g);
+		}
+	}
 }
 
 /*
@@ -180,18 +194,7 @@ build_filter(fz_context *ctx, fz_stream *chain, pdf_document *doc, pdf_obj *f, p
 		return fz_open_a85d(ctx, chain);
 
 	else if (pdf_name_eq(ctx, f, PDF_NAME(JBIG2Decode)))
-	{
-		fz_jbig2_globals *globals = NULL;
-		pdf_obj *obj = pdf_dict_get(ctx, p, PDF_NAME(JBIG2Globals));
-		if (obj)
-		{
-			if (!pdf_is_stream(ctx, obj))
-				fz_warn(ctx, "jbig2 globals is not a stream, skipping globals");
-			else
-				globals = pdf_load_jbig2_globals(ctx, doc, obj);
-		}
-		return fz_open_jbig2d(ctx, chain, globals); /* takes ownership of jbig2_globals */
-	}
+		return fz_open_jbig2d(ctx, chain, params->u.jbig2.globals); /* takes ownership of jbig2_globals */
 
 	else if (pdf_name_eq(ctx, f, PDF_NAME(JPXDecode)))
 		return fz_keep_stream(ctx, chain); /* JPX decoding is special cased in the image loading code */