[FFmpeg-user] Quality

[Ferdi Scholten]

I purchased a camera for the garden which has since been returned as the 
wifi was very flakey and has been replaced with a better trail camera.  
I took the videos off the sd card and there are one or two I want to keep.
>
> The camera created time based directories and put files of type .media 
> in the directories
>
> For example, in 2022/04/18/1650242594_0034 there are 4 files, 
> 0000.media, 0010.media, 0020.media, 0030.media.
>
> I have scripted a loop to to create .mp4 files, create a file list and 
> then concatenate them so I could view the videos.  Then, for this 
> example, as the camera was upside down, I've rotated the result.
>
> The ffmpeg commands I've used are:
>
> ffmpeg -i file.media file.mp4
> ffmpeg -f concat -safe 0 -i filelist.txt -c copy output.mp4
> ffmpeg -i output.mp4 -vf "transpose=2,transpose=2" output_r.mp4
>
> I am new to ffmpeg and would really like some help in preventing the 
> quality of the videos being degraded between the original .media files 
> and the final file.
>
>
> Alan
Do the transposing and transcoding in one run This prevents double 
encoding and thus loss of quality.

ffmpeg -i file.media -vf "transpose=2,transpose=2" file.mp4
ffmpeg -f concat -safe 0 -i filelist.txt -c copy output.mp4

Ferdi