[FFmpeg-user] I found the bugs

[Jim DeLaHunt]

On 2024-06-13 16:23, Mark Filipak wrote:

>> I don't see a clear statement of what you are trying to accomplish. I 
>> think it is: "I am trying to generate a video file which has correct 
>> PTS and DTS values and which plays correctly on MPV and FFplay, by 
>> splicing two video files together." But maybe it is: "I am trying to 
>> get FFmpeg's -vf showinfo filter and its -show_frames option to 
>> output consistent numbers."
>
> I have no control over what '-vf showinfo' & '-show_frames' report. 
> The issue is that they output different numbers and that the numbers 
> are different from reality.

Maybe your statement could be, "I have a 99-frame video and I want 
ffmpeg's -vf showinfo filter and its -show_frames option to output 
consistent numbers. The current output is inconsistent."

But ticket #11055 does seem to lack a clear statement of purpose, and it 
will be a better report when it has one.


>> You do supply the exact command lines you used. You also specified 
>> which version of FFmpeg you used. Good for you! But I don't see that 
>> you supplied "The full, uncut console output provided by ffmpeg -v 9 
>> -loglevel 99"….
>
> The console output for the 3 command lines is summarized in the table. 
> Their actual outputs are files.

Great! I suggest you attach them to the ticket.

In the ticket UI, under the heading "Attachments", there is a button, 
"Attach file". Try using that to attach the files containing the actual 
full, uncut console output.


>> I don't see where you supply the required input files to reproduce 
>> the 99-frame output video or the diagnostics you list.
>
> I uploaded the 4 second video twice and it was acknowledged. Isn't it 
> there? The ...whateveritis is so cryptic. It's made for programmers, 
> not human beings. 

The instructions at <https://ffmpeg.org/bugreports.html> say to "Email 
the ffmpeg mailing list and indicate the filename of the sample."  Have 
you done that?   Also, it might be helpful to state the filename of the 
sample as a sample in ticket #11055.

Also consider including the URL of a page listing those uploaded files, 
<https://streams.videolan.org/ffmpeg/incoming/11055/>. (IMHO this URL 
should be included in the instructions at bugreports.html, but that is a 
separate issue.)

On 2024-06-13 20:56, Mark Filipak wrote:
> At https://trac.ffmpeg.org/ticket/11055, there's someone with an alias 
> of "MasterQuestionable" who is harassing the heck out of me.

For what it's worth, I have read those comments and they don't strike me 
as "harassing".  I do actually see some progress in clarifying the 
information of the bug report.

A lot of the time I don't know what meaning "MasterQuestionable" is 
trying to communicate[1][2]. However sometimes I don't know what you are 
trying to communicate either.  Writing clearly about complicated data 
structures is hard, I guess.

Best regards,
     —Jim DeLaHunt

[1] "Technically DTS (Decoding Timestamps) shall be run-time decided. 
And shouldn't (also couldn't) be of concern before when." 
<https://trac.ffmpeg.org/ticket/11055#comment:15>
[2] "The ideal container format #3" 
<https://github.com/MasterInQuestion/talk/discussions/3#discussion-5219034> 
(I don't understand what this says about "DTS shall be run-time decided".