Manual selecting h264 Demuxer does not set h264 Demuxer correctly
Windows 10.0.18362
Bug has been tested and reproduced per VLC version after reset all VLC preferences and cache from start menu and inside VLC preference window.
VLC 2.2.8 is last known working
VLC 3.0.0 and above all do not correctly select h264 demuxer. Broken UI behaviour appears to vary slightly between VLC versions.
I have oddball h264 files obtained from a Swann/Reolink CCTV NVR. In VLC 2.2.8 and below the video portion of these files can be viewed (at an incorrect playback rate) if in VLC you do: Tools -> Preferences -> Show All Settings -> Input/Codecs -> Demuxer Change from Automatic to h264 video demuxer.
Starting in 3.0.0 VLC can not correctly set this preference. If you set the Demuxer to h264 video demuxer, VLC 3.0.0-3.0.7 on re-entering the Preference window will show HEVC/H.265 video demuxer selected. 3.0.8 does appear to show h264 selected but it does not function correctly.
If the setting is set by 2.2.8 and then VLC 3+(including 3.0.8) is opened and preferences are not changed the h264 video demuxer is correctly applied for the newer VLC. As soon as VLC 3.0.8 alters the preference it will again be in a broken state where the player can not correctly use this preference.
Activity
Just to be clear my bug report is not about the incorrect playback speed or any another playback problem, it is the failure to be able to manually set the h264 demuxer at all regardless of the file.
While I would love for vlc, ffmpeg and/or lav filters to correctly playback the files I somewhat consider that a pipe dream. The internet has been littered for years with people that want these files to play correct in VLC and/or directshow based players. The files appear to lack a standard container to help players know what they are attempting to play.
The NVR CPU is a very common hisilicon hi3535 and I believe these videos are "standard" for a hisilicon hi3535 and similar chips. The h264 video should also be interleaved with g711 alaw or mulaw audio that is never noticed by VLC or LAV Filters. A newer different version of these cameras has the audio in aac and again it is not detected by common players.
The official player based on the hi3535 SDK for these files can play the files at the correct playback speed with audio.
How do you set a manual FPS in VLC for 264 decoder? I can tell it to play slower/faster but I dont see a way to say "play @ 25fps"
added Component::Demuxers label
marked this issue as related to #22531
