[FFmpeg-devel] [PATCH] avformat/dump: Change precision of stream start offsets

[Marton Balint]

On Mon, 21 Apr 2025, softworkz . wrote:

>
>
>> -----Original Message-----
>> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of Gyan
>> Doshi
>> Sent: Montag, 21. April 2025 06:51
>> To: ffmpeg-devel at ffmpeg.org
>> Subject: Re: [FFmpeg-devel] [PATCH] avformat/dump: Change precision of
>> stream start offsets
>>
>>
>>
>> On 2025-04-21 01:41 am, softworkz wrote:
>>> From: softworkz <softworkz at hotmail.com>
>>>
>>> Changing this to 6 digits to align with other
>>> printed times
>>>
>>> Signed-off-by: softworkz <softworkz at hotmail.com>
>>> ---
>>>      avformat/dump: Change precision of stream start offsets
>>>
>>>      Changing this to 6 digits to align with other printed times
>>>
>>>      Signed-off-by: softworkz softworkz at hotmail.com
>>>
>>> Published-As: https://github.com/ffstaging/FFmpeg/releases/tag/pr-
>> ffstaging-72%2Fsoftworkz%2Fsubmit_start_offsets-v1
>>> Fetch-It-Via: git fetch https://github.com/ffstaging/FFmpeg pr-
>> ffstaging-72/softworkz/submit_start_offsets-v1
>>> Pull-Request: https://github.com/ffstaging/FFmpeg/pull/72
>>>
>>>   libavformat/dump.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/libavformat/dump.c b/libavformat/dump.c
>>> index 8c7db7b275..1bd0424f3d 100644
>>> --- a/libavformat/dump.c
>>> +++ b/libavformat/dump.c
>>> @@ -680,7 +680,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
>>>
>>>       if (st->start_time != AV_NOPTS_VALUE && st->start_time != 0 &&
>> st->time_base.den && st->time_base.num) {
>>>           const double stream_start = av_q2d(st->time_base) * st-
>>> start_time;
>>> -        av_log(NULL, AV_LOG_INFO, ", Start-Time %.3fs",
>> stream_start);
>>> +        av_log(NULL, AV_LOG_INFO, ", Start-Time %.6fs",
>> stream_start);
>>
>> The camel case is incongruous with the formatting of the text next To
>> It.
>
> Hi Gyan,
>
> as far as I'm seeing it, captions/labels are title case and values are
> lower case. I would consider "Start-Time" to be a caption/label. Let's
> look at an example:
>
>  Stream #0:0[0x8fd]: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], Level 40, 25 fps, 50 tbr, 90k tbn, Start-Time 32476.588s
>  Stream #0:1[0x907](dut): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 256 kb/s, Start-Time 32476.706s
>  Stream #0:2[0x908](dut): Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, 5.1(side), fltp, 448 kb/s, Start-Time 32476.643s
>  Stream #0:3[0x909](GOS): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 256 kb/s, Start-Time 32476.674s (visual impaired) (descriptions)
>  Stream #0:4[0x962](dut): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006), Start-Time 32476.588s
>  Stream #0:5[0x963](dut): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006), Start-Time 32476.719s (hearing impaired)

I think Gyan means fps, tbr or tbn. These are all lowercase and 
abbreviations. The one-line stream info should be as compact as possible. 
So we should make it shorter, and we should lose the "s" unit as 
well. Something like:

"in 1234.567"

IMHO that would fit better to the existing concept.

Regards,
Marton