Cleanup and use the chroma of the region to test if it can be blended.

  p_spu->p_blend->fmt_in.video.i_chroma = p_region->fmt.i_chroma;

src/video_output/vout_subpictures.c

@@ -247,6 +247,7 @@ static void RegionPictureRelease( picture_t *p_pic )
 {
     if( p_pic->p_data_orig ) free( p_pic->p_data_orig );
 }
+
 subpicture_region_t *__spu_CreateRegion( vlc_object_t *p_this,
                                          video_format_t *p_fmt )
 {
@@ -498,7 +499,7 @@ void spu_RenderSubpictures( spu_t *p_spu, video_format_t *p_fmt,
                 p_spu->p_blend->fmt_out.video.i_y_offset = 0;
             p_spu->p_blend->fmt_out.video.i_aspect = p_fmt->i_aspect;
             p_spu->p_blend->fmt_out.video.i_chroma = p_fmt->i_chroma;
-            p_spu->p_blend->fmt_in.video.i_chroma = VLC_FOURCC('Y','U','V','P');
+            p_spu->p_blend->fmt_in.video.i_chroma = p_region->fmt.i_chroma;
 
             p_spu->p_blend->p_module =
                 module_Need( p_spu->p_blend, "video blending", 0, 0 );
@@ -535,6 +536,7 @@ void spu_RenderSubpictures( spu_t *p_spu, video_format_t *p_fmt,
             }
             if( psz_modulename ) free( psz_modulename );
         }
+
         if( p_spu->p_text )
         {
             if( p_subpic->i_original_picture_height > 0 &&