thanks for the info. i did not say there are two streams. i said there are two levels of transcoding - normalizing the ingress into some standard codec and container and second one is the lower bitrate variant - that does not mean just one but as you said - it is/can be 240p, 360p, 480p, 720p, 1080p(source) and so on. in other words the encoding takes place at least two times.

> FFmpeg (x264) is plenty "fast enough" when tuned on commodity X86 hardware, when you have things like AVX extensions. Generally transcoding a 4-6 second segment of video should only be taking a couple of hundred milliseconds at a maximum

can you elaborate on this? i find that hard to believe from what i have seen and from the ton of "ffmpeg is slow" google search results. if that is truly the case, there might be light at the end of the tunnel. annecdotally, today i encoded 2sec h264 mp4 into av1 and it took only 2-3 minutes... vp9 took 8 seconds(still 4x). sure, that was not on a server but still, it's not like i am computing PI on the background.