[FFmpeg-devel] [PATCH] lavc/mediacodecdec: switch to the new generic filtering mechanism

Matthieu Bouron matthieu.bouron at gmail.com
Sat Jun 10 02:38:20 EEST 2017


On Fri, Jun 09, 2017 at 08:18:25PM -0300, James Almer wrote:
> On 6/9/2017 7:53 PM, Matthieu Bouron wrote:
> > ---
> >  libavcodec/mediacodecdec.c | 70 ++++++++--------------------------------------
> >  1 file changed, 12 insertions(+), 58 deletions(-)
> > 
> > diff --git a/libavcodec/mediacodecdec.c b/libavcodec/mediacodecdec.c
> > index 5bdeb6c1d7..0c77a78aa9 100644
> > --- a/libavcodec/mediacodecdec.c
> > +++ b/libavcodec/mediacodecdec.c
> > @@ -41,11 +41,9 @@ typedef struct MediaCodecH264DecContext {
> >  
> >      MediaCodecDecContext *ctx;
> >  
> > -    AVBSFContext *bsf;
> > -
> >      AVFifoBuffer *fifo;
> >  
> > -    AVPacket filtered_pkt;
> > +    AVPacket buffered_pkt;
> >  
> >  } MediaCodecH264DecContext;
> >  
> > @@ -58,8 +56,7 @@ static av_cold int mediacodec_decode_close(AVCodecContext *avctx)
> >  
> >      av_fifo_free(s->fifo);
> >  
> > -    av_bsf_free(&s->bsf);
> > -    av_packet_unref(&s->filtered_pkt);
> > +    av_packet_unref(&s->buffered_pkt);
> >  
> >      return 0;
> >  }
> > @@ -312,9 +309,6 @@ static av_cold int mediacodec_decode_init(AVCodecContext *avctx)
> >  
> >      const char *codec_mime = NULL;
> >  
> > -    const char *bsf_name = NULL;
> > -    const AVBitStreamFilter *bsf = NULL;
> > -
> >      FFAMediaFormat *format = NULL;
> >      MediaCodecH264DecContext *s = avctx->priv_data;
> >  
> > @@ -329,7 +323,6 @@ static av_cold int mediacodec_decode_init(AVCodecContext *avctx)
> >  #if CONFIG_H264_MEDIACODEC_DECODER
> >      case AV_CODEC_ID_H264:
> >          codec_mime = "video/avc";
> > -        bsf_name = "h264_mp4toannexb";
> >  
> >          ret = h264_set_extradata(avctx, format);
> >          if (ret < 0)
> > @@ -339,7 +332,6 @@ static av_cold int mediacodec_decode_init(AVCodecContext *avctx)
> >  #if CONFIG_HEVC_MEDIACODEC_DECODER
> >      case AV_CODEC_ID_HEVC:
> >          codec_mime = "video/hevc";
> > -        bsf_name = "hevc_mp4toannexb";
> >  
> >          ret = hevc_set_extradata(avctx, format);
> >          if (ret < 0)
> > @@ -410,25 +402,6 @@ static av_cold int mediacodec_decode_init(AVCodecContext *avctx)
> >          goto done;
> >      }
> >  
> > -    if (bsf_name) {
> > -    bsf = av_bsf_get_by_name(bsf_name);
> > -    if(!bsf) {
> > -        ret = AVERROR_BSF_NOT_FOUND;
> > -        goto done;
> > -    }
> > -
> > -    if ((ret = av_bsf_alloc(bsf, &s->bsf))) {
> > -        goto done;
> > -    }
> > -
> > -    if (((ret = avcodec_parameters_from_context(s->bsf->par_in, avctx)) < 0) ||
> > -        ((ret = av_bsf_init(s->bsf)) < 0)) {
> > -          goto done;
> > -    }
> > -    }
> > -
> > -    av_init_packet(&s->filtered_pkt);
> > -
> >  done:
> >      if (format) {
> >          ff_AMediaFormat_delete(format);
> > @@ -503,10 +476,10 @@ static int mediacodec_decode_frame(AVCodecContext *avctx, void *data,
> >      /* process buffered data */
> >      while (!*got_frame) {
> >          /* prepare the input data -- convert to Annex B if needed */
> 
> The second part of this comment can be removed.

Fixed.

> 
> > -        if (s->filtered_pkt.size <= 0) {
> > -            AVPacket input_pkt = { 0 };
> > +        if (s->buffered_pkt.size <= 0) {
> > +            AVPacket input_pkt;
> >  
> > -            av_packet_unref(&s->filtered_pkt);
> > +            av_packet_unref(&s->buffered_pkt);
> >  
> >              /* no more data */
> >              if (av_fifo_size(s->fifo) < sizeof(AVPacket)) {
> > @@ -514,36 +487,15 @@ static int mediacodec_decode_frame(AVCodecContext *avctx, void *data,
> >                      ff_mediacodec_dec_decode(avctx, s->ctx, frame, got_frame, avpkt);
> >              }
> >  
> > -            av_fifo_generic_read(s->fifo, &input_pkt, sizeof(input_pkt), NULL);
> > -
> > -            if (s->bsf) {
> > -            ret = av_bsf_send_packet(s->bsf, &input_pkt);
> > -            if (ret < 0) {
> > -                return ret;
> > -            }
> > -
> > -            ret = av_bsf_receive_packet(s->bsf, &s->filtered_pkt);
> > -            if (ret == AVERROR(EAGAIN)) {
> > -                goto done;
> > -            }
> > -            } else {
> > -                av_packet_move_ref(&s->filtered_pkt, &input_pkt);
> > -            }
> > -
> > -            /* {h264,hevc}_mp4toannexb are used here and do not require flushing */
> > -            av_assert0(ret != AVERROR_EOF);
> > -
> > -            if (ret < 0) {
> > -                return ret;
> > -            }
> > +            av_fifo_generic_read(s->fifo, &s->buffered_pkt, sizeof(input_pkt), NULL);
> 
> input_pkt is unused aside from this, so why not just do
> sizeof(s->buffered_pkt) instead and remove input_pkt altogether?

Fixed. I removed input_pkt as it was a left-over of the previous code.

> 
> >          }
> >  
> > -        ret = mediacodec_process_data(avctx, frame, got_frame, &s->filtered_pkt);
> > +        ret = mediacodec_process_data(avctx, frame, got_frame, &s->buffered_pkt);
> >          if (ret < 0)
> >              return ret;
> >  
> > -        s->filtered_pkt.size -= ret;
> > -        s->filtered_pkt.data += ret;
> > +        s->buffered_pkt.size -= ret;
> > +        s->buffered_pkt.data += ret;
> >      }
> >  done:

I also removed the above done label, which is now unused.

> >      return avpkt->size;
> > @@ -560,7 +512,7 @@ static void mediacodec_decode_flush(AVCodecContext *avctx)
> >      }
> >      av_fifo_reset(s->fifo);
> >  
> > -    av_packet_unref(&s->filtered_pkt);
> > +    av_packet_unref(&s->buffered_pkt);
> >  
> >      ff_mediacodec_dec_flush(avctx, s->ctx);
> >  }
> > @@ -578,6 +530,7 @@ AVCodec ff_h264_mediacodec_decoder = {
> >      .close          = mediacodec_decode_close,
> >      .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AVOID_PROBING,
> >      .caps_internal  = FF_CODEC_CAP_SETS_PKT_DTS,
> > +    .bsfs           = "h264_mp4toannexb",
> >  };
> >  #endif
> >  
> > @@ -594,6 +547,7 @@ AVCodec ff_hevc_mediacodec_decoder = {
> >      .close          = mediacodec_decode_close,
> >      .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AVOID_PROBING,
> >      .caps_internal  = FF_CODEC_CAP_SETS_PKT_DTS,
> > +    .bsfs           = "hevc_mp4toannexb",
> >  };
> >  #endif
> 
> LGTM otherwise if it works (Can't test).

Thanks for the review.

I've done some basic testing and it works but I'll wait a day or two
before pushing it. The updated patch is attached.

[...]

-- 
Matthieu B.
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