[feature request] Optimize input encoding schemes (base64, etc.)

[buu700]

I'm not extremely familiar with the internals of Brotli or compression in general, so this may be a naive suggestion, but intuitively I think it aligns philosophically with Brotli's use of a built-in dictionary. Would it be practical for a future version of Brotli to detect strings of formats like base64 and hex and decode them to binary before compressing / re-encode them as part of the decompression process?

I noticed just now during a comparison between compressing a binary file and the equivalent base64 (emscripten-core/emscripten#5104 (comment)) that the base64 version ended up larger, which it occurs to me shouldn't need to be the case given that the two contain almost exactly the same information.

[eustas]

Thanks for the suggestion, but we tend to keep brotli compressor pure.
This is a feature for brotli framing format: #462.
Could you place your FR into framing format discussion, please.

[buu700]

Got it, thanks, I'll post it there.