HLS encoding support

[Selur]

Looking at https://docs.peer5.com/guides/production-ready-hls-vod/ creating HLS compatible files doesn't seem complicated.
From what I gathered so far the HLS options are only required during muxing, so one could encode the mp4 source file with any encoder, as long as gop size is set to X seconds, automatically adding of GOPs on scence changes is disabled and the VBV values are set.
Those files could then be segmented using:

ffmpeg -i sourcefile -hls_time 4 -hls_playlist_type vod -hls_segment_filename "OUTPUT FOLDER/RESOLUTIO_%03d.ts" "OUTPUT FOLDER/RESOLUTIO.m3u8

so for a 480p source one would for example use:

ffmpeg -i "H:\Test.mp4" -hls_time 4 -hls_playlist_type vod -hls_segment_filename "h:\hlsTest\480p_%03d.ts" "h:\hlsTest\480p.m3u8

Note that hls_time can only be multiple of the gop size in seconds.

So the values a used would need to set are:
1. the gop size in seconds, the hls package size (needs to be a multiple of the gop size in seconds value)
2. The resolutions to target (width should be enough)
3. The VBV values.

After some thinking, about this I concluded, that I could add additional options to support creating a single file with segmented files and playlist, but adding an option which would tell Hybrid to create multiple resolution etc. in one go conflicts with too much of the inner workings of Hybrid.

Writing a small gui for the script from https://docs.peer5.com/guides/production-ready-hls-vod/ that works on Windows/Mac/Linux wouldn't be complicated either, but that would not be Hybrid but another tool.

Cu Selur