[BUG] Conversion from fragmented to normal mp4 failed

[manuelcjx]

Bug Report

Description

Video conversion to normal mp4 is failing a lot of time. leaving just the fragmented mp4 without the conversion.

Steps to Reproduce

Record, shut down the screen, wait 10-20 minutes, stop recording and see the file not converted.

Environment

Poco M6 4G HyperOS 3.0 Android 16

Priority

• [ X ] High

Debug Files:

FadCam_Debug.html

[anonfaded]

I'll check this today

[manuelcjx]

It doesnt happen always, around 50% of videos are correctly converted and 50% not converted, specially with longer videos. I think this is the exact moment where hybrid mp4 fails the conversion:

2026-08-12 18:19:45 WARN [FragmentedMp4MuxerWrap] Hybrid finalization failed — fMP4 left intact\njava.io.IOException: No such file or directory at sun.nio.ch.FileDispatcherImpl.size0(Native Method) at sun.nio.ch.FileDispatcherImpl.size(FileDispatcherImpl.java:103) at sun.nio.ch.FileChannelImpl.size(FileChannelImpl.java:365) at com.fadcam.media.FragmentedMp4MuxerWrapper.performHybridFinalization(FragmentedMp4MuxerWrapper.java:769) at com.fadcam.media.FragmentedMp4MuxerWrapper.stop(FragmentedMp4MuxerWrapper.java:363) at com.fadcam.opengl.GLRecordingPipeline.emergencyFinalizeMuxer(GLRecordingPipeline.java:1115) at com.fadcam.opengl.GLRecordingPipeline.stopRecording(GLRecordingPipeline.java:2266) at com.fadcam.services.RecordingService.lambda$stopRecording$16(RecordingService.java:1965) at com.fadcam.services.RecordingService.$r8$lambda$kpJnGDUmuPVR0HYslomf6BvLWrI(RecordingService.java:0) at com.fadcam.services.RecordingService$$ExternalSyntheticLambda3.run(D8$$SyntheticClass:0) at java.lang.Thread.run(Thread.java:1572)

[anonfaded]

I haven't been able to reproduce this on my side. It looks like the recording file is being lost during finalization, which can happen with aggressive background app management on some OEMs (e.g. HyperOS) during long screen-off recordings.

I've added lightweight logging to check whether the file still exists and can be recovered when this happens. Please update to the latest beta and send me the log ASAP if the issue occurs again:

https://github.com/anonfaded/FadCam/releases/tag/v4.0.0-beta10.4

Download FadCam_fmp4Fix.apk.

Also, please test with Internal Storage selected in FadCam Settings and let me know whether the issue still occurs there.

[manuelcjx]

Tried the new apk and still doesnt work. Also using Internal Storage doest make a change, it still fails on the final conversion from fragmented mp4 to normal mp4. All the battery optimizations is also off. Heres the new log files:

FadCam_Debug.html

[anonfaded]

Tried the new apk and still doesnt work. Also using Internal Storage doest make a change, it still fails on the final conversion from fragmented mp4 to normal mp4. All the battery optimizations is also off. Heres the new log files:

FadCam_Debug.html

The log file you attached is incomplete, it has no logs of video recording. Also see if your phone has some auto cleanup or something which kills the apps in background?
And if you have a PC, we can get the exact logs by the android system of what is killing the process. You can use our adb wrapper tool: https://github.com/anonfaded/FadCat

[manuelcjx]

Those are log files after a saved recording, this time using internal storage. I doesnt show any error this time but when I move the file to gallery using the app, the file is still a fragmeted mp4 and not a normal one.

FADCAM_debug.html

[anonfaded]

Was the previous version of beta working fine for you? before we implemented the hybridmp4? If yes please tell me the app version that worked fine.
And i just replaced the apk, once again download the FadCam_fmp4Fix.apk and test.
Remember to first turn on the Debug toggle in fadcam settings, then try reproducing the issue and in the end share the log file.

[manuelcjx]

Both previous version of beta before hybridmp4 and the new ones works fine, the difference is that previous to hybridmp4 I have to manually convert videos to mp4 using faditor automations or InShot App, and now some of the videos are correctly converted to normal mp4 and some of them not. I have tried this last apk you just uploaded and recorded multiple videos using both internal and custom folder, some of them are successful converted when finished and some of them not, so you can see if there are differences on the log files. Heres the new log files:

FADCAM_debug.html

[anonfaded]

I have patched the core to self-heal the stale fmp4 files. When you open the app, it detects the files and auto converts to standard mp4.
Please once again download the updated FadCam_fmp4Fix.apk apk and test:
https://github.com/anonfaded/FadCam/releases/tag/v4.0.0-beta10.4

[manuelcjx]

Tried the updated apk with 3 recordings, those are the results:

Recording 1 using widgets to start and stop the recording and a custom folder so the files appear directly on gallery: the conversion failed, even when trying to open the app still not converted.

Recording 2 using widgets to start and stop the recording and using internal storage: the conversion failed, even when opening the app and use the option to export to gallery.

Recording 3 using the button inside the app to start and stop the recording and using internal storage: the conversion is successful, I use the option to export to gallery and the file is a normal mp4.

Log file:

FADCAM_debug.html

[anonfaded]

I did some changed. Please once again download the updated FadCam_fmp4Fix.apk apk and test:
https://github.com/anonfaded/FadCam/releases/tag/v4.0.0-beta10.4

[manuelcjx]

Tested multiple recordings and now the feature when I opening the app it is working! Some of the videos are not correctly coverted but when I open the app they all appear on my gallery correctly converted, thanks! I also recived this message when opening the app:

Log files:

FADCAM_debug.html