add(docs) video conversion guide

[chrisgervang]

Putting an early version of this guide up for visibility. The image sequence sections need some more explanation about the cropping and trimming they demonstrate.

[coveralls]

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💛 - Coveralls

[chrisgervang]

Yeah, I want to keep it brief to help someone what they need quickly, but I think there's room for a bit more dissection of each new flag. Maybe a couple more "learn more" links to helpful docs if they're tricky to find.

[akre54]

Potentially of interest: https://ffmpegwasm.netlify.app/

[akre54]

This looks great! I wonder if we can shore up the intended audience a bit for these - I think someone learning about video codecs and ffmpeg for the first time shouldn’t need to learn the intricacies of the arguments passed to ffmpeg, or what the wasm port does. I wonder if this should be two separate docs; one for basics of transcoding (using Handbrake) and one for a more advanced “recipes” of common Hubble invocations and what they mean.

[chrisgervang]

Yeah, this could a bit daunting if they're not trying to grok codecs or get too deep.

For the basic handbrake use case, what about making it something everyone will see by putting it in the "introduction" article, which can also link to a these advance recipes?

[chrisgervang]

I'm going to ship this and can iterate on audience and content organization overtime.