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4K video is not moving on in playback


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I have a video file in 4K with a resolution of 3840 x 2160 in mp4 format. file size is about 1.3 GB of audio codec is the ACC and the H.264 video codec

When I play the movie in Watchout 6 choppy playback of the video file.
I have read in the forum that with the help of FFMpeg can encode iff file so that it flows properly during playback.
The only question is which value is appropriate to adjust, there are so many möjligher in FFMpeg so if anyone has tips on what I should try in the first place so I would be grateful.
If more information is needed to be able to answer my question so I can locate relevant information
/ Mathias
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Hi, most video editing tool and encoding tools seems to encode h.264 for web usage where smallest file size is desired. This results in more complex coding where more hardware resources are utilized. For WATCHOUT is doesn't really matter if the mp4 files will get slightly larger for the same quality but with lower complexity. If bi-directional frames are not used the CPU and memory usage is usually reduced by 50%. It's also possible to disable loop back filtering but that can introduce banding so the bit-rate needs to be increased. Also for faster seeking the intra frame interval (group of picture size) can be decreased from 300 to 30.


With ffmpeg you can try this:


ffmpeg.exe -i input -c:a copy -c:v libx264 -preset slow -profile:v main -g 30 -bf 0 -b:v 30M -y "output.mp4"


And for more optimizations:


ffmpeg.exe -i input -c:a copy -c:v libx264 -preset slow -tune fastdecode -profile:v baseline -g 30 -bf 0 -b:v 40M -y "output.mp4"


Where bf=number of b-frames, g=group of pictures (I-frame interval), b:v=bitrate for video- The fastdecode tune removes all loopback filters and should also set b-frames to 0. The -c:a simply copies the encoded audio input stream to the audio output stream. Hope this helps. You can adjust the bitrate settings to match your needs. 

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