ffv1: Store a flag in the global header that indicates if all frames are keyframes

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/ffv1.h

@@ -106,6 +106,7 @@ typedef struct FFV1Context {
     int16_t *sample_buffer;
 
     int ec;
+    int intra;
     int slice_damaged;
     int key_frame_ok;
 

libavcodec/ffv1dec.c

@@ -498,6 +498,8 @@ static int read_extra_header(FFV1Context *f)
 
     if (f->version > 2) {
         f->ec = get_symbol(c, state, 0);
+        if (f->minor_version > 2)
+            f->intra = get_symbol(c, state, 0);
     }
 
     if (f->version > 2) {

libavcodec/ffv1enc.c

@@ -534,7 +534,7 @@ static int write_extradata(FFV1Context *f)
     put_symbol(c, state, f->version, 0);
     if (f->version > 2) {
         if (f->version == 3)
-            f->minor_version = 2;
+            f->minor_version = 3;
         put_symbol(c, state, f->minor_version, 0);
     }
 
@@ -575,6 +575,7 @@ static int write_extradata(FFV1Context *f)
 
     if (f->version > 2) {
         put_symbol(c, state, f->ec, 0);
+        put_symbol(c, state, f->intra = (f->avctx->gop_size < 2), 0);
     }
 
     f->avctx->extradata_size = ff_rac_terminate(c);