[FFmpeg-devel] [PATCH v2] examples/decode_video: flush parser to fix missing frame

[mypopy at gmail.com]

On Thu, Sep 24, 2020 at 2:01 AM Zhao Zhili <quinkblack at foxmail.com> wrote:
>
> To reproduce, run decode_video with a single frame sample. No frame
> was decoded before the patch.
> ---
>  doc/examples/decode_video.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/doc/examples/decode_video.c b/doc/examples/decode_video.c
> index 18ee90a6c0..9ce3531d63 100644
> --- a/doc/examples/decode_video.c
> +++ b/doc/examples/decode_video.c
> @@ -92,6 +92,7 @@ int main(int argc, char **argv)
>      uint8_t *data;
>      size_t   data_size;
>      int ret;
> +    int eof;
>      AVPacket *pkt;
>
>      if (argc <= 2) {
> @@ -150,15 +151,14 @@ int main(int argc, char **argv)
>          exit(1);
>      }
>
> -    while (!feof(f)) {
> +    do {
>          /* read raw data from the input file */
>          data_size = fread(inbuf, 1, INBUF_SIZE, f);
> -        if (!data_size)
> -            break;
> +        eof = !data_size;
>
>          /* use the parser to split the data into frames */
>          data = inbuf;
> -        while (data_size > 0) {
> +        while (data_size > 0 || eof) {
>              ret = av_parser_parse2(parser, c, &pkt->data, &pkt->size,
>                                     data, data_size, AV_NOPTS_VALUE, AV_NOPTS_VALUE, 0);
If fread get a reading error occurred (not end-of-file), I don't think
we need to run this part.
>              if (ret < 0) {
> @@ -170,8 +170,10 @@ int main(int argc, char **argv)
>
>              if (pkt->size)
>                  decode(c, frame, pkt, outfilename);
> +            else if (eof)
> +                break;
>          }
> -    }
> +    } while (!eof);
>
>      /* flush the decoder */
>      decode(c, frame, NULL, outfilename);
> --