MJPGSize function to query size.

BUG=none
TEST=none
Review URL: https://webrtc-codereview.appspot.com/898004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@425 16f28f9a-4ce2-e073-06de-1de4eb20be90

README.chromium

 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 424
+Version: 425
 License: BSD
 License File: LICENSE
 

include/libyuv/convert.h

@@ -205,6 +205,11 @@ int MJPGToI420(const uint8* sample, size_t sample_size,
                uint8* dst_v, int dst_stride_v,
                int src_width, int src_height,
                int dst_width, int dst_height);
+
+// Query size of MJPG in pixels.
+LIBYUV_API
+int MJPGSize(const uint8* sample, size_t sample_size,
+             int* width, int* height);
 #endif
 
 // Note Bayer formats (BGGR) To I420 are in format_conversion.h

include/libyuv/version.h

@@ -11,6 +11,6 @@
 #ifndef INCLUDE_LIBYUV_VERSION_H_  // NOLINT
 #define INCLUDE_LIBYUV_VERSION_H_
 
-#define LIBYUV_VERSION 424
+#define LIBYUV_VERSION 425
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_  NOLINT

source/convert.cc

@@ -1567,6 +1567,21 @@ static void JpegI400ToI420(void* opaque,
   dest->h -= rows;
 }
 
+// Query size of MJPG in pixels.
+LIBYUV_API
+int MJPGSize(const uint8* sample, size_t sample_size,
+             int* width, int* height) {
+  // TODO(fbarchard): Port to C
+  MJpegDecoder mjpeg_decoder;
+  bool ret = mjpeg_decoder.LoadFrame(sample, sample_size);
+  if (ret) {
+    *width = mjpeg_decoder.GetWidth();
+    *height = mjpeg_decoder.GetHeight();
+  }
+  mjpeg_decoder.UnloadFrame();
+  return ret ? 0 : -1;  // -1 for runtime failure.
+}
+
 // MJPG (Motion JPeg) to I420
 // TODO(fbarchard): review w and h requirement. dw and dh may be enough.
 LIBYUV_API