Tweak png outputting functions.

Allow us to get an image as a png in a buffer.

3 files changed, 97 insertions, 61 deletions

diff --git a/fitz/fitz.h b/fitz/fitz.h
index 6e9d3515..2cea5424 100644
--- a/fitz/fitz.h
+++ b/fitz/fitz.h
@@ -1786,6 +1786,64 @@ fz_bitmap *fz_halftone_pixmap(fz_context *ctx, fz_pixmap *pix, fz_halftone *ht);
 typedef struct fz_font_s fz_font;
 
 /*
+	Generic output streams - generalise between outputting to a file,
+	a buffer, etc.
+*/
+typedef struct fz_output_s fz_output;
+
+struct fz_output_s
+{
+	fz_context *ctx;
+	void *opaque;
+	int (*printf)(fz_output *, const char *, va_list ap);
+	int (*write)(fz_output *, const void *, int n);
+	void (*close)(fz_output *);
+};
+
+/*
+	fz_new_output_with_file: Open an output stream onto a FILE *.
+
+	The stream does NOT take ownership of the FILE *.
+*/
+fz_output *fz_new_output_with_file(fz_context *, FILE *);
+
+/*
+	fz_new_output_with_buffer: Open an output stream onto a buffer.
+
+	The stream does NOT take ownership of the buffer.
+*/
+fz_output *fz_new_output_with_buffer(fz_context *, fz_buffer *);
+
+/*
+	fz_printf: fprintf equivalent for output streams.
+*/
+int fz_printf(fz_output *, const char *, ...);
+
+/*
+	fz_write: fwrite equivalent for output streams.
+*/
+int fz_write(fz_output *out, const void *data, int len);
+
+/*
+	Output a pixmap to an output stream as a png.
+*/
+void fz_output_png(fz_context *ctx, const fz_pixmap *pixmap, fz_output *out, int savealpha);
+
+/*
+	Get an image as a png in a buffer.
+*/
+fz_buffer *fz_image_as_png(fz_context *ctx, fz_image *image, int w, int h);
+
+/*
+	fz_close_output: Close a previously opened fz_output stream.
+
+	Note: whether or not this closes the underlying output method is
+	method dependent. FILE * streams created by fz_new_output_with_file
+	are NOT closed.
+*/
+void fz_close_output(fz_output *);
+
+/*
 	The different format handlers (pdf, xps etc) interpret pages to a
 	device. These devices can then process the stream of calls they
 	recieve in various ways:
@@ -2100,59 +2158,6 @@ void fz_free_text_page(fz_context *ctx, fz_text_page *page);
 void fz_analyze_text(fz_context *ctx, fz_text_sheet *sheet, fz_text_page *page);
 
 /*
-	Generic output streams - generalise between outputting to a file,
-	a buffer, etc.
-*/
-typedef struct fz_output_s fz_output;
-
-struct fz_output_s
-{
-	fz_context *ctx;
-	void *opaque;
-	int (*printf)(fz_output *, const char *, va_list ap);
-	int (*write)(fz_output *, const void *, int n);
-	void (*close)(fz_output *);
-};
-
-/*
-	fz_new_output_with_file: Open an output stream onto a FILE *.
-
-	The stream does NOT take ownership of the FILE *.
-*/
-fz_output *fz_new_output_with_file(fz_context *, FILE *);
-
-/*
-	fz_new_output_with_buffer: Open an output stream onto a buffer.
-
-	The stream doesn NOT take ownership of the buffer.
-*/
-fz_output *fz_new_output_with_buffer(fz_context *, fz_buffer *);
-
-/*
-	fz_printf: fprintf equivalent for output streams.
-*/
-int fz_printf(fz_output *, const char *, ...);
-
-/*
-	fz_write: fwrite equivalent for output streams.
-*/
-int fz_write(fz_output *out, const void *data, int len);
-
-/*
-	Output a pixmap to an output stream as a png.
-*/
-void fz_output_pixmap_to_png(fz_context *ctx, fz_pixmap *pixmap, fz_output *out, int savealpha);
-
-/*
-	fz_close_output: Close a previously opened fz_output stream.
-
-	Note: whether or not this closes the underlying output method is
-	method dependent. FILE * streams created by fz_new_output_with_file
-	are NOT closed.
-*/
-void fz_close_output(fz_output *);
-
-/*
 	fz_print_text_sheet: Output a text sheet to a file as CSS.
 */
 void fz_print_text_sheet(fz_context *ctx, fz_output *out, fz_text_sheet *sheet);
diff --git a/fitz/res_pixmap.c b/fitz/res_pixmap.c
index 12d5956e..5c12f19b 100644
--- a/fitz/res_pixmap.c
+++ b/fitz/res_pixmap.c
@@ -574,7 +574,7 @@ fz_write_png(fz_context *ctx, fz_pixmap *pixmap, char *filename, int savealpha)
 
 	fz_try(ctx)
 	{
-		fz_output_pixmap_to_png(ctx, pixmap, fz_new_output_with_file(ctx, fp), savealpha);
+		fz_output_png(ctx, pixmap, fz_new_output_with_file(ctx, fp), savealpha);
 	}
 	fz_always(ctx)
 	{
@@ -587,7 +587,7 @@ fz_write_png(fz_context *ctx, fz_pixmap *pixmap, char *filename, int savealpha)
 }
 
 void
-fz_output_pixmap_to_png(fz_context *ctx, fz_pixmap *pixmap, fz_output *out, int savealpha)
+fz_output_png(fz_context *ctx, const fz_pixmap *pixmap, fz_output *out, int savealpha)
 {
 	static const unsigned char pngsig[8] = { 137, 80, 78, 71, 13, 10, 26, 10 };
 	unsigned char head[13];
@@ -676,6 +676,42 @@ fz_output_pixmap_to_png(fz_context *ctx, fz_pixmap *pixmap, fz_output *out, int
 	fz_free(ctx, cdata);
 }
 
+fz_buffer *
+fz_image_as_png(fz_context *ctx, fz_image *image, int w, int h)
+{
+	fz_pixmap *pix = fz_image_get_pixmap(ctx, image, image->w, image->h);
+	fz_buffer *buf = NULL;
+	fz_output *out;
+
+	fz_var(buf);
+	fz_var(out);
+
+	fz_try(ctx)
+	{
+		if (pix->colorspace != fz_device_gray || pix->colorspace != fz_device_rgb)
+		{
+			fz_pixmap *pix2 = fz_new_pixmap(ctx, fz_device_rgb, pix->w, pix->h);
+			fz_convert_pixmap(ctx, pix2, pix);
+			fz_drop_pixmap(ctx, pix);
+			pix = pix2;
+		}
+		buf = fz_new_buffer(ctx, 1024);
+		out = fz_new_output_with_buffer(ctx, buf);
+		fz_output_png(ctx, pix, out, 0);
+	}
+	fz_always(ctx)
+	{
+		fz_close_output(out);
+		fz_drop_pixmap(ctx, pix);
+	}
+	fz_catch(ctx)
+	{
+		fz_drop_buffer(ctx, buf);
+		fz_rethrow(ctx);
+	}
+	return buf;
+}
+
 unsigned int
 fz_pixmap_size(fz_context *ctx, fz_pixmap * pix)
 {
diff --git a/fitz/text_output.c b/fitz/text_output.c
index 7aceddef..6942eb67 100644
--- a/fitz/text_output.c
+++ b/fitz/text_output.c
@@ -258,15 +258,10 @@ fz_print_text_page_html(fz_context *ctx, fz_output *out, fz_text_page *page)
 				break;
 			default:
 				{
-					fz_pixmap *pix = fz_image_get_pixmap(ctx, image->image, image->image->w, image->image->h);
-					fz_buffer *buf = fz_new_buffer(ctx, 1024);
-					fz_output *out2 = fz_new_output_with_buffer(ctx, buf);
-					fz_output_pixmap_to_png(ctx, pix, out2, 0);
-					fz_close_output(out2);
+					fz_buffer *buf = fz_image_as_png(ctx, image->image, image->image->w, image->image->h);
 					fz_printf(out, "image/png;base64,");
 					send_data_base64(out, buf);
 					fz_drop_buffer(ctx, buf);
-					fz_drop_pixmap(ctx, pix);
 					break;
 				}
 			}