swscale: fix failing fate tests.

isGray() is left as a FIXME for later.

libavutil/pixdesc.c

@@ -219,7 +219,6 @@ const AVPixFmtDescriptor av_pix_fmt_descriptors[PIX_FMT_NB] = {
         .comp = {
             {0,0,1,0,7},        /* Y */
         },
-        .flags = PIX_FMT_PAL,
     },
     [PIX_FMT_MONOWHITE] = {
         .name = "monow",
@@ -567,7 +566,7 @@ const AVPixFmtDescriptor av_pix_fmt_descriptors[PIX_FMT_NB] = {
             {0,5,3,0,15},       /* G */
             {0,5,5,0,15},       /* B */
         },
-        .flags = PIX_FMT_BE,
+        .flags = PIX_FMT_RGB | PIX_FMT_BE,
     },
     [PIX_FMT_RGB48LE] = {
         .name = "rgb48le",

libswscale/swscale_internal.h

@@ -552,9 +552,18 @@ const char *sws_format_name(enum PixelFormat format);
 #define isRGB(x) \
     (av_pix_fmt_descriptors[x].flags & PIX_FMT_RGB)
 
+#if 0 // FIXME
 #define isGray(x) \
     (!(av_pix_fmt_descriptors[x].flags & PIX_FMT_PAL) && \
      av_pix_fmt_descriptors[x].nb_components <= 2)
+#else
+#define isGray(x)       (           \
+           (x)==PIX_FMT_GRAY8       \
+        || (x)==PIX_FMT_Y400A      \
+        || (x)==PIX_FMT_GRAY16BE    \
+        || (x)==PIX_FMT_GRAY16LE    \
+    )
+#endif
 
 #define isRGBinInt(x)   (           \
            (x)==PIX_FMT_RGB48BE     \