Bug 409269

Summary:	nvenc
Product:	[Applications] kdenlive	Reporter:	NVDA-Dev <louise9841>
Component:	Rendering & Export	Assignee:	Jean-Baptiste Mardelle <jb>
Status:	RESOLVED WORKSFORME
Severity:	crash	CC:	fritzibaby
Priority:	NOR	Flags:	fritzibaby: timeline_corruption+
Version First Reported In:	19.04.2
Target Milestone:	---
Platform:	Mint (Ubuntu based)
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description NVDA-Dev 2019-06-28 04:34:25 UTC

SUMMARY
Video Renders but only produces sound/audio when using ANY nvenc or cuda codecs. FFmpeg is compiled with cuda, nvenc, etc support. I play in ANY player and it will only play the sound of the video with a black screen(instead of video) and a black thumbnail when video is closed. When I immediately go to render the video after saving, a prompt(about my custom render profile for mp4) comes up in my render profile saying "Unsupported video codec: h264_nvenc" with an error sign right next to my profile. After deleting and recreating the same render profile, the prompt goes away and I can happily render but video engine utilization is 0 percent while gpu is up and down in the 20 percent range.As said earlier, the output of the render results in a black screen with playing audio no matter what player used. This does NOT happen on kdenlive 17.xx.xx when install from official software repositories for Ubuntu 18.04/Mint 19.1. Video is rendered perfectly with sound and video and video engine utilization is around 14-20 percent. To be 100 percent sure its not my ffmpeg compile being crap(or maybe it is I just dont know 100 percent yet) I installed shotcut as a test(just because) and it renders with nvenc, cuda just fine. The second problem i am having(this feature isnt available in 17.xx.xxx so only reserved for 19.xxx.xxx) is using nvenc on the timeline preview, proxies and preview render. Using nvenc on proxies, timeline, preview render result in a failure prompt that reads "Unknown decoder 'h264_cuvid'". When using regular x264 in place of nvenc in the above mentioned ways it works 100 percent normally. This is repeatable in the snap & flatpak versions. In the Appimage I dont even have the option to enable gpu movit libary even when changing the env variables to my own compiled libaries. This is on nvidia 430.26 driver as well as cuda 10.1 update 1. And the OS is Linux Mint 19.1.

STEPS TO REPRODUCE
1.
2.
3.

OBSERVED RESULT

EXPECTED RESULT

SOFTWARE/OS VERSIONS
Windows:
macOS:
Linux/KDE Plasma:
(available in About System)
KDE Plasma Version:
KDE Frameworks Version:
Qt Version:

ADDITIONAL INFORMATION

Comment 1 NVDA-Dev 2019-06-28 04:55:20 UTC

STEPS TO REPRODUCE
1. Open a video in kdenlive, place it in timeline, go to render video, add a profile based on mp4, change libx264 to h264_nvenc. name it nvenc, click ok to add a new profile, then select it as render profile for video, click render, after render play video youll get no sound. Restart kdenlive go to render and skip adding a profile, click on nvenc profile again, you will get unsupported codec: h264_nvenc, delete old profile do same steps above click render and will still get black video with sound. And video engine utilization 0 percent.
2. For proxies go into project settings select x264_nvenc(in my install at least you will see and error sign next to it) select it for timeline preview then go to proxies enable them and images as well, select x264_nvenc as proxies encoder. Drag video into timeline. Right click video in source window select proxy clip and you will see "Unknown decoder 'h264_cuvid'" in the problem log. 

OBSERVED RESULT


EXPECTED RESULT

1. Black screen when playing rendered video with no video and no thumbnail(black thumbnail) when using nvenc encoder but audio is clearly working. Video engine utilization 0 percent while rendering. gpu utilzation 20+ percent while rendering.



2. Proxies failure when using cuda/cuvid/nvenc as decoder. You will get "Unknown decoder 'h264_cuvid'" in problem log. 

3. Install version 17.xxx.xxx from ubuntu/mint repos and with properly configured ffmpeg you wil get no problems with gpu acceleration.

Comment 2 emohr 2019-08-04 12:53:23 UTC

Unfortunately GPU acceleration is switched of in 19.04 due to many bugs. Dev team is working on it to re-integrate GPU acceleration.

BTW: Do you are a developer? If yes the team is looking for help integrating GPU acceleration.

Comment 3 Bug Janitor Service 2019-08-19 04:33:09 UTC

Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!

Comment 4 Bug Janitor Service 2019-09-03 04:33:11 UTC

This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!