[FFmpeg-devel] [PATCH] avfilter/af_loudnorm: correctly initialize PTS

[Muhammad Faiz]

On Sun, Feb 4, 2018 at 3:32 PM, Paul B Mahol <onemda at gmail.com> wrote:
> On 2/4/18, Muhammad Faiz <mfcc64 at gmail.com> wrote:
>> On Sat, Feb 3, 2018 at 9:22 PM, Niklas Haas <ffmpeg at haasn.xyz> wrote:
>>> From: Niklas Haas <git at haasn.xyz>
>>>
>>> Right now, the PTS always starts out as 0, which causes problems on a
>>> seek or when inserting this filter mid-stream.
>>>
>>> Initialize it instead to AV_NOPTS_VALUE and copy the PTS from the first
>>> frame instead if this is the case.
>>> ---
>>>  libavfilter/af_loudnorm.c | 5 ++++-
>>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/libavfilter/af_loudnorm.c b/libavfilter/af_loudnorm.c
>>> index a7f11cbe6e..314b25fa39 100644
>>> --- a/libavfilter/af_loudnorm.c
>>> +++ b/libavfilter/af_loudnorm.c
>>> @@ -431,6 +431,9 @@ static int filter_frame(AVFilterLink *inlink, AVFrame
>>> *in)
>>>          av_frame_copy_props(out, in);
>>>      }
>>>
>>> +    if (s->pts == AV_NOPTS_VALUE)
>>> +        s->pts = in->pts;
>>> +
>>>      out->pts = s->pts;
>>>      src = (const double *)in->data[0];
>>>      dst = (double *)out->data[0];
>>> @@ -763,7 +766,7 @@ static int config_input(AVFilterLink *inlink)
>>>          inlink->partial_buf_size = frame_size(inlink->sample_rate, 3000);
>>>      }
>>>
>>> -    s->pts =
>>> +    s->pts = AV_NOPTS_VALUE;
>>>      s->buf_index =
>>>      s->prev_buf_index =
>>>      s->limiter_buf_index = 0;
>>> --
>>> 2.16.1
>>
>> Output pts ideally should be based on input pts in all cases
>> (not only in the first pts case), because input pts may be non-monotonic.
>
> That have nothing to do with this patch.

Of course, if ideal fix isn't trivial, this fix is enough.