[FFmpeg-devel] [PATCH] avcodec/wma: handle run_level_decode error

[Olivier Crête]

Hi Andreas,

> Generally, one should forward error codes and not make up some on the
> fly; in this case, the callee does not return proper error codes, so
> this should be fixed, too (but not in the same commit and not
> necessarily by you). Even more importantly, the callee emits an error
> message, stating that an error will be ignored, which will no longer
> true with this patch.

If I understand correctly, the "ignoring" refers to the block being
ignored because of errors, not to the error being ignored.

Is there any chance to get this into 4.4.1 ?

Olivier

On Wed, 2021-08-11 at 16:54 +0200, Stéphane Cerveau wrote:
> Consider data as invalid if ff_wma_run_level_decode
> gets out with an error.
> 
> It avoids an unpleasant sound distorsion.
> 
> See http://trac.ffmpeg.org/ticket/9358
> ---
>  libavcodec/wmadec.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/libavcodec/wmadec.c b/libavcodec/wmadec.c
> index d627bbe50e..74ea8cea77 100644
> --- a/libavcodec/wmadec.c
> +++ b/libavcodec/wmadec.c
> @@ -606,10 +606,11 @@ static int wma_decode_block(WMACodecContext *s)
>               * there is potentially less energy there */
>              tindex = (ch == 1 && s->ms_stereo);
>              memset(ptr, 0, s->block_len * sizeof(WMACoef));
> -            ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex],
> +            if (ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex],
>                                      s->level_table[tindex], s->run_table[tindex],
>                                      0, ptr, 0, nb_coefs[ch],
> -                                    s->block_len, s->frame_len_bits, coef_nb_bits);
> +                                    s->block_len, s->frame_len_bits, coef_nb_bits))
> +              return AVERROR_INVALIDDATA;
>          }
>          if (s->version == 1 && s->avctx->channels >= 2)
>              align_get_bits(&s->gb);

-- 
Olivier Crête
olivier.crete at collabora.com