Add interrupt callback with default timeout of 30s.

[peters]

In order to speed up the review process I've set up a x64 debug/release project over at https://github.com/peters/opencv.ffmpeg with the latest official ffmpeg 2.8.5 binaries included.

Fixes #5730.

/cc @alalek @vpisarev

[alalek]

Thanks! Look good to me.
Interrupt callback has been added since: "2011-11-13 - lavf 53.21.0 / 53.15.0" , so conditional compilation may required for some legacy versions of ffmpeg.
I checked Ubuntu 12.04 LTS, there is ffmpeg format 53.21.1, so it is fine. I hope ROS builds will pass also.

Could you please squash commits into one (git rebase -i HEAD~4)

[peters]

Thanks! Look good to me.

Awesome 👍

Could you please squash commits into one (git rebase -i HEAD~4)

Done

I hope ROS builds will pass also

Is those builds internal because I can't find them in the waterfall overview.

[peters]

What is the reason hardware accelleration is disabled for the windows build? There is some documentation over at https://trac.ffmpeg.org/wiki/HWAccelIntro. But I don't want to spend more time on this if there is nothing to gain from it :)

[alalek]

👍

[alalek]

What is the reason hardware accelleration is disabled for the windows build?

I believe to reduce size of binaries and additional dependencies for mingw builds

[peters]

Aha, then I have much to gain from pursuing this further. I'll do some research and possibly create a repository on github allowing hardware accelleration on Windows for those who need it :)

[peters]

The build is failing, but it appears unrelated to my changes.

[peters]

@alalek Thanks for reviewing this so fast. I'm going to donate the 500$ bounty to opencv foundation just for that 👍 🏆

[sturkmen72]

what should i do to take effect of this fix. i recompiled the library but nothing has changed. should i download opencv_ffmpeg.dll ? or i missed something when rebuild the library.

[alalek]

OpenCV build for Windows uses prebuilt binaries with ffmpeg wrapper. And they are not updated and not integrated into OpenCV yet.

I prepared the latest version of ffmpeg wrapper binaries, but they are not tested (also ffmpeg release is not updated). They are build via this script (Linux with Docker is required)

Also you can use this OpenCV patch, which automatically downloads ffmpeg binaries.

Or you can try to replace ffmpeg.dll's from there, but this may require to disable CMake downloader

[sturkmen72]

@alalek thank you so much

[BitLoose]

@alalek I'm using VS2015 on Windows, would like to modify and compile the functions such as icvSetCaptureProperty_FFMPEG_p etc., but can't find the source code. Is it available?

[alalek]

It is just an imported symbols from ffmpeg windows wrapper.
Implementation is here, but it is not easy to build ffmpeg wrapper (refer to https://github.com/Itseez/opencv_3rdparty/tree/ffmpeg/master/ffmpeg). Also you may try to use approach from this PR description.

[BitLoose]

That's a shame, if it was more accesible people would be more able to add to the code.
What's the best way in your opinion to add the audio stream playback?

[peters]

@BitLoose It's actually really easy to make changes to the wrapper on Windows. Just grab my project over at https://github.com/peters/opencv.ffmpeg and hit F5.

[PatriciaReyes]

@alalek how can I update opencv_ffmpeg.dll for linux?

[alalek]

@PatriciaReyes There is no separate opencv_ffmpeg.dll on Linux. To enable ffmpeg support in OpenCV you need to install ffmpeg development packages (-dev/-devel, depends on Linux distribution) and rerun OpenCV CMake

[PatriciaReyes]

@alalek Thanks, i'm going to check that to make sure i'm doing it fine... I have this big issue, do you think you could help me with it? [http://stackoverflow.com/questions/36750685/c-suddenly-blocks-on-reading-a-frame-from-ip-camera-using-videocapture/36756653?noredirect=1#comment61124042_36756653]

[marcassin22]

@peters I've managed to make your project work but I can't find how to use it with my other projects. Should I just copy the dll's or I need to recompile OpenCV with them?

[michaildrozdov]

@peters Even after all these years it saved my day.:)

[cbasavaraj]

Hi, does the solution here work even for capturing gstreamer pipelines? For example,
cv2.VideoCapture("fake ! gstreamer ! pipeline", cv2.CAP_GSTEAMER)
Thanks

[lidorshimoni]

Hi, does the solution here work even for capturing gstreamer pipelines? For example,
cv2.VideoCapture("fake ! gstreamer ! pipeline", cv2.CAP_GSTEAMER)
Thanks

did you manage to implement the timeout with gstreamer pipeline?

[cbasavaraj]

Hi @lidorshimoni, I found this workaround, and adapted it for my purpose. Happy holidays!