I read that it is better to extract from vob H264 files within a .ts to have a lossless and more accurate sample, easy to cut, is that correct ?
I used these commands :
ffmpeg -i VTS_01_1.VOB -acodec libfaac -aq 100 -ac 2 -vol 2048 -vcodec libx264 -preset veryslow -crf 18 -threads 2 manu1.mp4 ffmpeg -i manu1.mp4 -c copy -bsf:v h264_mp4toannexb -f mpegts intermediate1.ts
I did extract two video samples from the intermediate .ts file with that kind of command :
ffmpeg -ss 43 -i intermediate1.ts -vcodec copy -vframes 1400 -acodec copy 1-manubus.ts
if I play separately this .ts files in vlc, they are both completely decoded, no frames are missing
ffmpeg -analyzeduration 200M -probesize 150M -i "concat:1-manubus.ts|2-manuchoisit.ts" -c:v libx264 -crf 18 -preset slow -bsf:a aac_adtstoasc -force_key_frames 0 1990-Manu_Redpants.mp4
But then, When I play the final file, the first 6 sec are a frozen frame and then comes the audio and video streams perfectly synchro until the end. If I play the first part 1-manubus.ts, the 6 first seconds exists and are not missing, what's happening ? Something related to first frame not being the I-frames ?