I edit a video such that it speeds up by 8x where the speaker is silent and by 2x when he is speaking. And to do that I use ffmpeg in such a manner:
ffmpeg -i C:\Users\TheD4\Desktop\uni1.mp4 -filter_complex "[0:v]trim=0:0.98,setpts=1*(PTS-
STARTPTS)[v0]; [0:a]atrim=0:0.98,asetpts=PTS-STARTPTS,atempo=1[a0]
[0:v]trim=0.98:1.598,setpts=0.5*(PTS-STARTPTS)[v1]; [0:a]atrim=0.98:1.598,asetpts=PTS- STARTPTS,atempo=2[a1]; [0:v]trim=1.598:1.946,setpts=1*(PTS-STARTPTS)[v2];
[0:a]atrim=1.598:1.946,asetpts=PTS-STARTPTS,atempo=1[a2]; [0:v]trim=1.946:1.975,setpts=0.5*(PTS-
STARTPTS)[v3]; [0:a]atrim=1.946:1.975,asetpts=PTS-STARTPTS,atempo=2[a3];............
[0:v]trim=1529.04:1537.34,setpts=1*(PTS-STARTPTS)[v1652]; [0:a]atrim=1529.04:1537.34,asetpts=PTS-
STARTPTS,atempo=1[a1652]; [0:v]trim=1537.34:1537.55,setpts=0.5*(PTS-STARTPTS)[v1653];
[0:a]atrim=1537.34:1537.55,asetpts=PTS-STARTPTS,atempo=2[a1653];
[0:v]trim=1537.55:1538.73,setpts=1*(PTS-STARTPTS)[v1654]; [0:a]atrim=1537.55:1538.73,asetpts=PTS-
STARTPTS,atempo=1[a1654]; [0:v]trim=1538.73:1539.15,setpts=0.5*(PTS-STARTPTS)[v1655];
[0:a]atrim=1538.73:1539.15,asetpts=PTS-STARTPTS,atempo=2[a1655]; [v0][a0][v1][a1][v2][a2][v3]
[a3]..........[v1652][a1652][v1653][a1653][v1654][a1654][v1655][a1655]concat=n=1656:v=1:a=1" -preset
superfast -profile:v baseline
But the thing is, as you might have noticed the filter goes into the thousands, and so the total number of caracters is high(in this example there are around 200000), but cmd(8000) or powershell(30000) have less than that. So to get around that limitation, I divided all of that into smaller parts, but here is where the problem starts, as I run more and more of the "parts code" and ffmpeg does work on later and later parts of the video, the process of making the video from those smaller parts becomes slower as well, even though the size of the video is the same. To see what is wrong, I ran the code from a couple of hundred seconds(so instead of starting from 0s it start from let's say 500s) and I noticed the same effect. So what I think happens is that ffmpeg goes through the entirety of the video until it reaches the specified start. So here is my question is there a way to tell ffmpeg to ignore the start of the video and to start immediately from where I need it to, maybe something like this:
ffmpeg -i C:\Users\TheD4\Desktop\uni1.mp4[500:] -filter_complex ........