[Ffmpeg-devel] low_delay and has_b_frames

[Baptiste Coudurier]

Hi

I noticed that even when using -intra, encoder avctx has has_b_frames
set to 1.

I checked mpegvideo.c and indeed:

@@ -1169,12 +1169,12 @@
     switch(avctx->codec->id) {
     case CODEC_ID_MPEG1VIDEO:
         s->out_format = FMT_MPEG1;
-        s->low_delay= 0; //s->max_b_frames ? 0 : 1;
+        s->low_delay= s->max_b_frames ? 0 : 1;
         avctx->delay= s->low_delay ? 0 : (s->max_b_frames + 1);
         break;
     case CODEC_ID_MPEG2VIDEO:
         s->out_format = FMT_MPEG1;
-        s->low_delay= 0; //s->max_b_frames ? 0 : 1;
+        s->low_delay= s->max_b_frames ? 0 : 1;
         avctx->delay= s->low_delay ? 0 : (s->max_b_frames + 1);
         s->rtp_mode= 1;
         break;

later:
    avctx->has_b_frames= !s->low_delay;

What is the reason behind not using max_b_frames ?
Should I modify has_b_frames set by taking max_b_frames into account ?

-- 
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