Add GZipMiddleware to root demo instance

[dfaker]

Adding GZipMiddleware middleware for all requests over 1000 bytes represents a 23%+ saving in bytes transferred for large images with little speed change, tests with image response from 1 step at 1024x2048 purely for image size:

Gzip Off:

Bytes	Time
4.2 MB	14.75 s
4.2 MB	13.79 s
4.2 MB	14.12 s
4.2 MB	14.04 s
4.2 MB	14.07 s

Gzip On:

Bytes	Time
3.2 MB	14.36 s
3.2 MB	14.44 s
3.2 MB	14.26 s
3.2 MB	14.14 s
3.2 MB	14.53 s

[HookedBehemoth]

It might be worthwhile to use better lossless formats like webp, jpegxl or avif. Serving them compressed and offering an uncompressed download would also help drastically. In my testing, that reduced the size by factor 30.

[dfaker]

You mean generally, or with Gradio? It does look like a big improvement is in the works with gradio-app/gradio#2265 as @evanjs spotted, still slightly limited to the PIL supported formats for now though.

[HookedBehemoth]

Gradio. I plugged in pillow-avif-plugin for testing.