obscure ahh formats

shorter devlog for now. i finally fixed the 4 formats that were not working from the previous devlog: .amv, .mpeg, .mpg, and .vob.

.mpeg, .mpg, and .vob were very easy and simply needed me to ensure that the audio bitrate was always to the power of 2 (e.g. 128kbps, 256kbps, etc).

.amv however.. was a bit more interesting. audio bitrate had to be 32kbps, sample rate 22050Hz, and extra arguments were needed. i needed to add the -block_size argument and then calculate the right size by dividing the sample rate (22050) with the FPS. this should be easy - audio to video conversions (using the album art / solid colour as the bg) always use 1 FPS to convert as quick as possible, but I actually had to force 3 FPS because AMV block sizes can only be between 32 and 8192. as such, the lowest FPS I could go was 3 since 22050 / 3 = 7350.