#58 Random stops of encoding

[Peter]

Hey, I am doing mainly h264 -> h265, but also h265 -> h265 have problems. Using nvenc.
Encoding randomly just stops after few % of progress. In task manager, FFmpeg process just drops to 0% of CPU usage, using about few hundreds MB of RAM. Progressbar and numbers in FFmpeg Batch stops and nothing happens until I manually cancel encoding.
There is nothing in log, just regular lines about encoding bitrate, speed, etc. If I check "make more verbose log" it will not start to encode at all. Numbers and progressbar are not changing.

Tried multiple various video files, encountered this problem in all of them.

Hardware:
Ryzen 7 3700x
16GB DDR4
GTX1060 6GB
Win11 x64 with latest updates

What I tried or observed:
1. this problem is in every version newer than 2.5.4. Versions 2.6.x were probably never released, as I cant find any. Tried every version from 2.7.0 to 2.7.6. Portable version have this problem too.

1. updated GPU drivers. no help.

2. tried older versions of ffmpeg.exe on 2.7.x, even ffpmeg.exe v4.4 from working FFmpeg Batch v2.5.4. No help. I think that problem is probably in FFmpeg Batch encoder itself and not in ffmpeg.exe. On the contrary, FFmpeg Batch v2.5.4 with latest ffmpeg.exe v5.0.1 works OK.

3. tried changing GPU decode from "none" to "cuda", "dxva" "d3d11va". No help.

4. if I click "try it on console", it works OK, which is weird. Maybe some problem with GUI itself?

[Abel]

Are you using multi-file encoding? How many threads?

[Peter]

no muti file, just sequential encoding. one by one.

[Abel]

I'm afraid I can't reproduce the issue, no issues with one nvidia and one amd video cards.
Which parameters are you using?

[Peter]

For ex., parameters for encoding h265 to smaller size is:
-map 0 -c copy -c:v hevc_nvenc -profile:v 0 -preset slow -rc constqp -qp 29 -rc-lookahead 48 -g 250

[Abel]

Hi, those parameters are contradictory (-c copy and -c:v hevc_nvenc).
I don't own a compatible hevc_nvenc card, only hs64_nvenc.
I've tried with your parameters during a 1 hour session and found no issues.

I'm afraid I can't reproduce the issue. I would need a video card like yours, or you would need to set up the application development environment to try and debug it yourself.

Anyway I hope that with earlier versions you can still fulfill for your encoding purposes.

[Peter]

[Peter]

[Peter]

//UPDATE. I tried to encode h265 file and I removed "-c copy", so preset is:
-map 0 -c:v hevc_nvenc -profile:v 0 -preset slow -rc constqp -qp 31 -rc-lookahead 48 -g 250 and its working on 2.5.4

[Peter]

...but its not work in 2.7.6

[Abel]

I understand, '-c copy' is required to stream copy all the non-video streams.
I see you are encoding from a network location. That could be a source for issues.
Are you caching files before encoding?

[Peter]

It stops even when I encode from local SSD in PC. What making me confused is, that if I encode it in console by clicking "try it on console" button, it works everytime even in v2.7.x versions. I dont know about other code changes in 2.7.x versions, but I can see a new insight like window in right up corner of FFmpeg Batch. This was added in 2.7.0, which is next version after 2.5.4 and which might cause trouble. But i dont know, just guessing, because nothing newer that 2.5.4 not works here.

[Abel]

It is very dificult to diagnose random errors that display no specific error.
I can't provide individual support for and issue that no one else has reported, I have limited resources.

If you can create a screencast with all the steps that lead you to the problem, it may be of help. I have no way of diagnosing your hardware environment.

[Peter]

Hey, recently, I discovered something new regarding this problem. Tested on portable versions 2.7.7 and 2.8.0.
When I leave setting about location of encoded file to default (.\FFBatch), encoding will run properly until end, with no problem. I have multiple drives in computer, and always had set it to E:\, because I am used to it. I have tested to set it to another drive (D:) and problem also happened. But after I set it to its default (.\FFBatch), encoding will always run properly until the end. Maybe this may help you to locate possible problem.

I made some small file for testing this. If problem appear, it always stops around 18.8%. Like there was some certain timer, or program check for something. When problem occurs, all counters will stop and only "time elapsed" one is still counts time.

I uploaded my test file for you to test:
https://drive.google.com/file/d/1K6E0JK3Y1fa_J-0xmWRC6SCYPYRdRyzq/view?usp=sharing

The preset I use is still the same one:
-map 0 -c copy -c:v hevc_nvenc -profile:v 0 -preset slow -rc constqp -qp 29 -rc-lookahead 48 -g 250

I also tried one of default presets, which came with FFBatch:
-map 0 -c:v libx264 -crf 23 -preset ultrafast -c:a copy
...and when I changed its output directory, it stopped at 33.8%

With older version 2.5.4, there is no problem at all.
I am encoding from local SSD storage, not over LAN.

[Abel]

Hi, have you tried using the new setting in v2.8.0 "Quick queue file adding".
Just for testing purposes.

[Peter]

Tried it just nov on v2.8.0. When I click "sequential encoding" as I do always, it shows small window with "trying selected preset" and the indicator goes round and round and nothing happens. When I click "Abort", it changes to "aborting", but also nothing happens. I need to kill the app.

[Abel]

You can check "Do not try preset", it is not 100% reliable depending of source file or parameters.

[Peter]

Tried that, and now the big progressbar at bottom dies not move at all, only the small one in the video list on right side. But it still ends at 19% and stop moving. Only think that moves is "time elapsed" counter

[Abel]

Also, for testing purposes, could you try encoding using right-click menu - Encode.

[Peter]

I dont have any "encode" in right click menu, when I right-click on video file. Only one options regarding FFMPEG there is Send to -> FFMPEG. However, even if I try this, problem still remains.

[Abel]

I've done a slight change in a new feature since 2.7.x versions, you could try replacing your current .exe. Patched 2.8.0

[Peter]

It seems that you did it :-) Everything working fine with patched exe. Tried to convert multiple various files (VP9 to h265, divx to h265, h265 to h265) and everything worked correctly.

Tried also with enabled "quick queue file adding" and "do not try preset" and it works. But bottom progressbar does not move, and there are no info around it like bitrate, etc. However, when encoding ends, progressbar will show instantly 100% and missing data will show around it too.

When fiddling with "quick queue file adding", I discovered one glitch: When I add file to list with "quick queue file adding" enabled, then disable "quick queue file adding" and try to encode, it shows Unhandled exception (String was not recognized as a valid TimeSpan) error. I think its because with "quick queue file adding" enabled, it does not show stats of video added in the list.

I was doing some programming in the past too. Im curious and can you pls tell me what was causing this weird problem?

[Abel]

It seems that a periodic check on destination drive in order to warn user if drive was running out of space, it was failing somehow. I've reprogrammed it to ignore exceptions.

[Peter]

Thanks :-)