[FFmpeg-devel] [PATCH] Don't adjust start time for MP3 files; packets are not adjusted.

[Dale Curtis]

Bump again for this one too. Thanks. The Arch Linux distro is awaiting
resolution of this issue.

- dale

On Mon, May 4, 2020 at 11:10 AM Dale Curtis <dalecurtis at chromium.org> wrote:

> Any comments on this? Thanks.
>
> - dale
>
> On Thu, Apr 30, 2020 at 12:42 PM Dale Curtis <dalecurtis at chromium.org>
> wrote:
>
>> Ping for this patch. Thanks
>>
>> - dale
>>
>> On Thu, Apr 23, 2020 at 4:33 PM Dale Curtis <dalecurtis at chromium.org>
>> wrote:
>>
>>> This is a patch Chromium has carried for a while, we forgot to send it
>>> upstream. 7546ac2fee4 made it so that the start_time for mp3 files is
>>> adjusted for skip_samples. However, this appears incorrect because
>>> subsequent packet timestamps are not adjusted and skip_samples are
>>> applied by deleting data from a packet without changing the timestamp.
>>>
>>> E.g., we are told the start_time is ~25ms and we get a packet with a
>>> timestamp of 0 that has had the skip_samples discarded from it. As such
>>> rendering engines may incorrectly discard everything prior to the
>>> 25ms thinking that is where playback should officially start. Since the
>>> samples were deleted without adjusting timestamps though, the true
>>> start_time is still 0.
>>>
>>> Other formats like MP4 with edit lists will adjust both the start
>>> time and the timestamps of subsequent packets to avoid this issue.
>>>
>>> Signed-off-by: Dale Curtis <dalecurtis at chromium.org>
>>>
>>