vaapidecode: do not discard video info props when the format changed.

gst_video_info_set_format() does not preserve video info properties. In
order to keep important information in the caps such as interlace mode,
framerate, pixel aspect ratio, ... we need to manually copy back those
properties after setting the new video format.

https://bugzilla.gnome.org/show_bug.cgi?id=722276

diff --git a/gst/vaapi/gstvaapidecode.c b/gst/vaapi/gstvaapidecode.c
index da422e2..8ccc169 100644 (file)
--- a/gst/vaapi/gstvaapidecode.c
+++ b/gst/vaapi/gstvaapidecode.c
@@ -129,6 +129,23 @@ gst_vaapidecode_update_sink_caps(GstVaapiDecode *decode, GstCaps *caps)
     return TRUE;
 }
 
+static void
+gst_vaapidecode_video_info_change_format(GstVideoInfo *info,
+    GstVideoFormat format, guint width, guint height)
+{
+    GstVideoInfo vi = *info;
+
+    gst_video_info_set_format (info, format, width, height);
+
+    info->interlace_mode = vi.interlace_mode;
+    info->flags = vi.flags;
+    info->views = vi.views;
+    info->par_n = vi.par_n;
+    info->par_d = vi.par_d;
+    info->fps_n = vi.fps_n;
+    info->fps_d = vi.fps_d;
+}
+
 static gboolean
 gst_vaapidecode_update_src_caps(GstVaapiDecode *decode,
     const GstVideoCodecState *ref_state)
@@ -165,7 +182,7 @@ gst_vaapidecode_update_src_caps(GstVaapiDecode *decode,
     vis = *vi;
     switch (feature) {
     case GST_VAAPI_CAPS_FEATURE_GL_TEXTURE_UPLOAD_META:
-        gst_video_info_set_format(&vis, GST_VIDEO_FORMAT_RGBA,
+        gst_vaapidecode_video_info_change_format(&vis, GST_VIDEO_FORMAT_RGBA,
             GST_VIDEO_INFO_WIDTH(vi), GST_VIDEO_INFO_HEIGHT(vi));
         features = gst_caps_features_new(
             GST_CAPS_FEATURE_META_GST_VIDEO_GL_TEXTURE_UPLOAD_META, NULL);
@@ -176,7 +193,7 @@ gst_vaapidecode_update_src_caps(GstVaapiDecode *decode,
             format=ENCODED + memory:VASurface caps feature are provided.
             Meanwhile, providing a random format here works but this is
             a terribly wrong thing per se. */
-            gst_video_info_set_format(&vis, GST_VIDEO_FORMAT_NV12,
+            gst_vaapidecode_video_info_change_format(&vis, GST_VIDEO_FORMAT_NV12,
                 GST_VIDEO_INFO_WIDTH(vi), GST_VIDEO_INFO_HEIGHT(vi));
 #if GST_CHECK_VERSION(1,3,0)
             if (feature == GST_VAAPI_CAPS_FEATURE_VAAPI_SURFACE)