.dav video files | play | convert to .mp4 | concatenate .mp4 files

1. How to play .dav video files?

Wondershare UniConverter

2. How to convert .dav files into .mp4 files?

>ffmpeg -y -i input-file.dav -c:v libx264 -crf 24 output-file.mp4

3. How to concatenate .mp4 files?

For Linux:

$ cat mylist.txt
file '/path/to/file1'
file '/path/to/file2'
file '/path/to/file3'
    
$ ffmpeg -f concat -safe 0 -i mylist.txt -c copy output.mp4

For Windows:

(echo file 'first file.mp4' & echo file 'second file.mp4' )>list.txt
ffmpeg -safe 0 -f concat -i list.txt -c copy output.mp4