[FFmpeg-devel] [PATCH]lavc/amrwbdec: Do not ignore NO_DATA frames

[James Almer]

On 1/30/2019 10:47 AM, Carl Eugen Hoyos wrote:
> 2019-01-29 22:47 GMT+01:00, Carl Eugen Hoyos <ceffmpeg at gmail.com>:
>> Hi!
>>
>> Attached patch fixes decoding NO_DATA amr-wb frames.
> 
> Now with patch.
> 
> Carl Eugen

> From 0a8c318c49ec358ad646ed601588154cf7d7da37 Mon Sep 17 00:00:00 2001
> From: Carl Eugen Hoyos <ceffmpeg at gmail.com>
> Date: Tue, 29 Jan 2019 22:46:37 +0100
> Subject: [PATCH] lavc/amrwbdec: Do not ignore NO_DATA frames.
> 
> Fixes the actual output duration of the sample in ticket #7113.
> ---
>  libavcodec/amrwbdata.h |    2 +-
>  libavcodec/amrwbdec.c  |    9 ++++++++-
>  2 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/libavcodec/amrwbdata.h b/libavcodec/amrwbdata.h
> index 8a8cbfd..95c0aaa 100644
> --- a/libavcodec/amrwbdata.h
> +++ b/libavcodec/amrwbdata.h
> @@ -1884,7 +1884,7 @@ static const float lpf_7_coef[31] = { // low pass, 7kHz cutoff
>  /** Core frame sizes in each mode */
>  static const uint16_t cf_sizes_wb[] = {
>      132, 177, 253, 285, 317, 365, 397, 461, 477,
> -    40 /// SID/comfort noise frame
> +    40, 0, 0, 0, 0, 0, 0
>  };
>  
>  #endif /* AVCODEC_AMRWBDATA_H */
> diff --git a/libavcodec/amrwbdec.c b/libavcodec/amrwbdec.c
> index 47fe7eb..b488a5d 100644
> --- a/libavcodec/amrwbdec.c
> +++ b/libavcodec/amrwbdec.c
> @@ -1119,12 +1119,19 @@ static int amrwb_decode_frame(AVCodecContext *avctx, void *data,
>      buf_out = (float *)frame->data[0];
>  
>      header_size      = decode_mime_header(ctx, buf);
> +    expected_fr_size = ((cf_sizes_wb[ctx->fr_cur_mode] + 7) >> 3) + 1;
> +
> +    if (ctx->fr_cur_mode == NO_DATA) {
> +        for (i = 0; i < frame->nb_samples; i++)
> +            buf_out[i] = 0.f;

You can use av_samples_set_silence() for this.

> +        *got_frame_ptr = 1;
> +        return expected_fr_size;
> +    }
>      if (ctx->fr_cur_mode > MODE_SID) {
>          av_log(avctx, AV_LOG_ERROR,
>                 "Invalid mode %d\n", ctx->fr_cur_mode);
>          return AVERROR_INVALIDDATA;
>      }
> -    expected_fr_size = ((cf_sizes_wb[ctx->fr_cur_mode] + 7) >> 3) + 1;
>  
>      if (buf_size < expected_fr_size) {
>          av_log(avctx, AV_LOG_ERROR,
> -- 
> 1.7.10.4
>