Add support for webp image format

diff --git a/clients/cairo-util.c b/clients/cairo-util.c
index 2f780a7..df2fb1b 100644 (file)
--- a/clients/cairo-util.c
+++ b/clients/cairo-util.c
@@ -21,6 +21,8 @@
  * OF THIS SOFTWARE.
  */
 
+#include "../config.h"
+
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
@@ -32,6 +34,10 @@
 #include <jpeglib.h>
 #include <png.h>
 
+#ifdef HAVE_WEBP
+#include <webp/decode.h>
+#endif
+
 #define ARRAY_LENGTH(a) (sizeof (a) / sizeof (a)[0])
 
 void
@@ -514,14 +520,98 @@ load_png(FILE *fp)
                                                    width, height, stride);
 }
 
+#ifdef HAVE_WEBP
+
+static cairo_surface_t *
+load_webp(FILE *fp)
+{
+       WebPDecoderConfig config;
+       uint8_t buffer[16 * 1024];
+       int len;
+       VP8StatusCode status;
+       WebPIDecoder *idec;
+
+       if (!WebPInitDecoderConfig(&config)) {
+               fprintf(stderr, "Library version mismatch!\n");
+               return NULL;
+       }
+
+       /* webp decoding api doesn't seem to specify a min size that's
+          usable for GetFeatures, but 256 works... */
+       len = fread(buffer, 1, 256, fp);
+       status = WebPGetFeatures(buffer, len, &config.input);
+       if (status != VP8_STATUS_OK) {
+               fprintf(stderr, "failed to parse webp header\n");
+               WebPFreeDecBuffer(&config.output);
+               return NULL;
+       }
+
+       config.output.colorspace = MODE_BGRA;
+       config.output.u.RGBA.stride =
+               cairo_format_stride_for_width(CAIRO_FORMAT_RGB24,
+                                             config.input.width);
+       config.output.u.RGBA.size =
+               config.output.u.RGBA.stride * config.input.height;
+       config.output.u.RGBA.rgba =
+               malloc(config.output.u.RGBA.stride * config.input.height);
+       config.output.is_external_memory = 1;
+       if (!config.output.u.RGBA.rgba) {
+               WebPFreeDecBuffer(&config.output);
+               return NULL;
+       }
+
+       rewind(fp);
+       idec = WebPINewDecoder(&config.output);
+       if (!idec) {
+               WebPFreeDecBuffer(&config.output);
+               return NULL;
+       }
+
+       while (!feof(fp)) {
+               len = fread(buffer, 1, sizeof buffer, fp);
+               status = WebPIAppend(idec, buffer, len);
+               if (status != VP8_STATUS_OK) {
+                       fprintf(stderr, "webp decode status %d\n", status);
+                       WebPIDelete(idec);
+                       WebPFreeDecBuffer(&config.output);
+                       return NULL;
+               }
+       }
+
+       WebPIDelete(idec);
+       WebPFreeDecBuffer(&config.output);
+
+       return cairo_image_surface_create_for_data (config.output.u.RGBA.rgba,
+                                                   CAIRO_FORMAT_RGB24,
+                                                   config.input.width,
+                                                   config.input.height,
+                                                   config.output.u.RGBA.stride);
+}
+
+#endif
+
+
+struct image_loader {
+       char header[4];
+       int header_size;
+       cairo_surface_t *(*load)(FILE *fp);
+};
+
+static const struct image_loader loaders[] = {
+       { { 0x89, 'P', 'N', 'G' }, 4, load_png },
+       { { 0xff, 0xd8 }, 2, load_jpeg },
+#ifdef HAVE_WEBP
+       { { 'R', 'I', 'F', 'F' }, 4, load_webp }
+#endif
+};
+
 cairo_surface_t *
 load_image(const char *filename)
 {
        cairo_surface_t *surface;
-       static const unsigned char png_header[] = { 0x89, 'P', 'N', 'G' };
-       static const unsigned char jpeg_header[] = { 0xff, 0xd8 };
        unsigned char header[4];
        FILE *fp;
+       int i;
 
        fp = fopen(filename, "rb");
        if (fp == NULL)
@@ -529,18 +619,22 @@ load_image(const char *filename)
 
        fread(header, sizeof header, 1, fp);
        rewind(fp);
-       if (memcmp(header, png_header, sizeof png_header) == 0)
-               surface = load_png(fp);
-       else if (memcmp(header, jpeg_header, sizeof jpeg_header) == 0)
-               surface = load_jpeg(fp);
-       else {
+       for (i = 0; i < ARRAY_LENGTH(loaders); i++) {
+               if (memcmp(header, loaders[i].header,
+                          loaders[i].header_size) == 0) {
+                       surface = loaders[i].load(fp);
+                       break;
+               }
+       }
+
+       fclose(fp);
+
+       if (i == ARRAY_LENGTH(loaders)) {
                fprintf(stderr, "unrecognized file header for %s: "
                        "0x%02x 0x%02x 0x%02x 0x%02x\n",
                        filename, header[0], header[1], header[2], header[3]);
                surface = NULL;
        }
 
-       fclose(fp);
-
        return surface;
 }

diff --git a/configure.ac b/configure.ac
index a2bb537..02f4040 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -123,11 +123,16 @@ if test x$enable_clients == xyes; then
                             [have_poppler=yes], [have_poppler=no])
   PKG_CHECK_MODULES(CAIRO_EGL, [cairo-egl >= 1.11.3 $cairo_modules],
                    [have_cairo_egl=yes], [have_cairo_egl=no])
-
   AS_IF([test "x$have_cairo_egl" = "xyes"],
         [AC_DEFINE([HAVE_CAIRO_EGL], [1], [Have cairo-egl])],
         [AC_MSG_WARN([Cairo-EGL not found - clients will use cairo image])])
 
+  PKG_CHECK_MODULES(WEBP, [libwebp], [have_webp=yes], [have_webp=no])
+  AS_IF([test "x$have_webp" = "xyes"],
+        [AC_DEFINE([HAVE_WEBP], [1], [Have webp])])
+  CLIENT_LIBS="$CLIENT_LIBS $WEBP_LIBS"
+  CLIENT_CFLAGS="$CLIENT_CFLAGS $WEBP_CFLAGS"
+
   AC_CHECK_LIB([jpeg], [jpeg_CreateDecompress], have_jpeglib=yes)
   if test x$have_jpeglib == xyes; then
     CLIENT_LIBS="$CLIENT_LIBS -ljpeg"