a possible bug in gstreamer?

[Mark Howell]

On 06/07/2017 11:25 AM, kendell clark wrote:
> hi all
>
> I'm a new user to this list, having just signed up about a month ago. 
> My name is Kendell clark, and I've been a gnu linux user since august 
> of 2011. I am visually impaired, and work with the vinux project, 
> which is an accessible linux distro for those who need assistive 
> technologies, such as the orca screen reader, on board on screen 
> keyboard, and magnification, as well as other programs. I am also not 
> a programmer, yet. However, I use linux every day and want to help 
> improve some of the best code I've ever had the pleasure of using, and 
> that is gstreamer. 

Kendell, welcome. I didn't want you to go unanswered so I'm offering 
some comments below that I hope will a) help you fix your problems and 
b) enable your increased participation and contribution here and in 
other open source projects with a bajillion moving parts and priorities.

> I'd like to report what I think might, maybe, be a bug or two in 
> gstreamer. First, in opening the matroska video file format (.mkv    
> ). In totem, which is actually called videos now, attempting to open a 
> mkv file results in the following error.
>
> "an error occurred internal data stream error."
>

[snipped some narrative about possible bugs]

It's entirely possible you have found one or more gstreamer bugs. This 
is the place where people who know how to work those bugs can be found. 
Those folks are busy adding features, curing ills, and moving the thing 
forward and have many people and issues competing for their attention. 
To maximize the likelihood of getting their attention, do whatever you 
can to put each issue on a silver platter. That means reduce how much 
work and research they have to do to reproduce the problem, and reduce 
the search space or variables for solving it. Some suggestions:

* First go see if your issue looks like another one already in bugzilla 
(https://gstreamer.freedesktop.org/bugs/). Try to avoid filing a 
duplicate... instead add useful comments or test cases to the existing 
bug. Often it's not obvious that a bug is a duplicate, and the 
responsible devs may figure it out and mark it as a duplicate as they go.

* Read other bugs for examples of what to report and how.

* If your issue is not a duplicate, file a bug, one for each issue, as 
well as you can separate them.

* In each bug report, include a test case that is as simple, direct, and 
self-contained as possible (like a gst-launch commandline and a link to 
a publicly available media file, or a gst-launch test case that can run 
entirely from test "equipment" inside the gstreamer borders like 
videotestsrc).

* Be real specific about versions (try gst-launch-1.0 --version, or if 
you are building from source... what tag or commit? did it come from 
your Linux distribution's repo?) Folks here will be more motivated to 
cure a bug on the current master or release branch than an older 
release. Also it may be worthwhile to know what kernel you are running 
(uname -a), what version(s) of other relevant libraries you are running. 
Architecture? ( x86_64, x86, etc)

* If you can, try it on another system or with a different version of 
gstreamer. Does it do the same on Windows, or a Mac, or on the release 
from the Ubuntu repo? Does 1.8.x work fine with your file but 1.12.x 
doesn't?

* After you file the bug, watch its activity and be ready to respond to 
requests for logs, test cases, library versions, 
try-this-instead-of-that, etc.

Cheers,

Mark.