[HELP] What are the prerequisites for Level 4.2?

[chris]

I agree that 1080p@50fps is fine for H.264 High@4.2.
An Hybrid does not complain here when I use it.
According to the command line a fps of 100 is used,...
I think that was a bug in an older version of Hybrid.
-> I'll send you a link to my current dev version.

Cu Selur

Hi Selur, greets!

I'm using Hybrid 2021.04.06.1. 

I think this may be due to a quirk of the MKV container of the source, its frame rate is defined as 50/VFR fps, although the elementary stream reports 25 fps (correct, it's interlaced). I noted Hybrid said it was preferring the container frame rate,

Analyzing video streams...
  Analyzing video stream (0).
=> Detected stretch factor for track 0 is 2/1.
Prefering container (50) over stream frame rate (25)
Notice: Video stream raw and container lenght differ, other streched streams might exist.

MediaInfo:

Frame rate mode                          : Variable
Frame rate                               : 50.000 FPS
Original frame rate                      : 25.000 FPS

The source is a 1080i50 TFF.

I just aborted my current encode to check frame rate, and Hybrid appears to have encoded as a 100 fps H.264 stream, as I thought it might.

Stream #0:0: Video: h264 (High), yuv420p(tv, bt709/unknown/unknown, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 100 fps, 100 tbr, 1200k tbn, 200 tbc

I remuxed with ffmpeg and had to -fflags +genpts for the incomplete .h264 stream; this played back at 100 fps though it had actually been improperly interpreted as 50 fps and not correctly deinterlaced. 4x slowing down the playback rate resulted in a 25 fps video with burned in interlacing. 

Some twiddling may be required to get Hybrid to interpret these files properly :-)