[FFmpeg-devel] [PATCH 1/4] avcodec/mediacodecdec: clarify delay_flush specific code

[Matthieu Bouron]

On Tue, Apr 24, 2018 at 01:59:23PM -0700, Aman Gupta wrote:
> From: Aman Gupta <aman at tmm1.net>
> 
> ---
>  libavcodec/mediacodecdec.c        | 24 +++---------------------
>  libavcodec/mediacodecdec_common.c | 12 ++++++++++++
>  2 files changed, 15 insertions(+), 21 deletions(-)
> 
> diff --git a/libavcodec/mediacodecdec.c b/libavcodec/mediacodecdec.c
> index 0d4a853f07..e5d3e6a0af 100644
> --- a/libavcodec/mediacodecdec.c
> +++ b/libavcodec/mediacodecdec.c
> @@ -419,27 +419,9 @@ static int mediacodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
>      MediaCodecH264DecContext *s = avctx->priv_data;
>      int ret;
>  
> -    /*
> -     * MediaCodec.flush() discards both input and output buffers, thus we
> -     * need to delay the call to this function until the user has released or
> -     * renderered the frames he retains.
> -     *
> -     * After we have buffered an input packet, check if the codec is in the
> -     * flushing state. If it is, we need to call ff_mediacodec_dec_flush.
> -     *
> -     * ff_mediacodec_dec_flush returns 0 if the flush cannot be performed on
> -     * the codec (because the user retains frames). The codec stays in the
> -     * flushing state.
> -     *
> -     * ff_mediacodec_dec_flush returns 1 if the flush can actually be
> -     * performed on the codec. The codec leaves the flushing state and can
> -     * process again packets.
> -     *
> -     * ff_mediacodec_dec_flush returns a negative value if an error has
> -     * occurred.
> -     *
> -     */
> -    if (ff_mediacodec_dec_is_flushing(avctx, s->ctx)) {
> +    /* in delay_flush mode, wait until the user has released or rendered

NIT: In delay_flush mode, [...]

> +       all retained frames. */
> +    if (s->delay_flush && ff_mediacodec_dec_is_flushing(avctx, s->ctx)) {
>          if (!ff_mediacodec_dec_flush(avctx, s->ctx)) {
>              return AVERROR(EAGAIN);
>          }
> diff --git a/libavcodec/mediacodecdec_common.c b/libavcodec/mediacodecdec_common.c
> index e59cf19aad..0c27624dea 100644
> --- a/libavcodec/mediacodecdec_common.c
> +++ b/libavcodec/mediacodecdec_common.c
> @@ -764,6 +764,18 @@ int ff_mediacodec_dec_receive(AVCodecContext *avctx, MediaCodecDecContext *s,
>      return AVERROR(EAGAIN);
>  }
>  
> +/*
> +* ff_mediacodec_dec_flush returns 0 if the flush cannot be performed on
> +* the codec (because the user retains frames). The codec stays in the
> +* flushing state.
> +*
> +* ff_mediacodec_dec_flush returns 1 if the flush can actually be
> +* performed on the codec. The codec leaves the flushing state and can
> +* process again packets.
> +*
> +* ff_mediacodec_dec_flush returns a negative value if an error has
> +* occurred.
> +*/
>  int ff_mediacodec_dec_flush(AVCodecContext *avctx, MediaCodecDecContext *s)
>  {
>      if (!s->surface || atomic_load(&s->refcount) == 1) {
> -- 
> 2.14.2
> 

LGTM.

-- 
Matthieu B.