hwaccel: mpeg2: decode first field, if requested.
authorGwenole Beauchesne <gb.devel@gmail.com>
Sun, 18 Mar 2012 08:46:58 +0000 (09:46 +0100)
committerMartin Storsjö <martin@martin.st>
Sun, 8 Apr 2012 10:08:52 +0000 (13:08 +0300)
If user opted to present fields as they come, then the first field
picture needs to be submitted to the HW for decoding. In particular,
this fixes MPEG-2 decoding of interlaced streams.

Tested on Intel Cedar Trail, Sandy Bridge and Ivy Bridge platforms.
Someone reported on the ffmpeg-devel@ list this also works on DXVA
(Windows) and other Linux platforms (NVIDIA, through the VA wrapper).

This also means a similar patch to non-hwaccel VDPAU may be necessary.

Note: I believe the SLICE_FLAG_ALLOW_FIELD is useless since the first
field shall always be submitted to the HW anyway. Nobody uses HW accels
(dxva, vaapi, vdpau, etc.) without that flag though.

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
libavcodec/mpeg12.c

index 27765b3..8cdc704 100644 (file)
@@ -1590,6 +1590,12 @@ static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
             return -1;
         }
 
+        if (s->avctx->hwaccel &&
+            (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
+            if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
+                av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode first field\n");
+        }
+
         for (i = 0; i < 4; i++) {
             s->current_picture.f.data[i] = s->current_picture_ptr->f.data[i];
             if (s->picture_structure == PICT_BOTTOM_FIELD) {