add a novideo content-type

[Nathan Hallquist]

Some of my users really dislike video frames in xterm. With this patch, users can (1) set a novideo content type and (2) set a guesser rule from an environment variable (from a systemd entry I have):

Environment=XPRA_CONTENT_TYPE_DEFS=class-instance:xterm=novideo

[Antoine Martin]

I like the idea.

We could just add a new flag like TEXT_NOVIDEO. This would apply to all applications that are meant to be text.

This does not use lossless:

            return nonvideo(info="lossless content-type")

It will use a non-video encoding, usually at a high quality setting, but not lossless unless you change the quality value with this call.
And if you do, then you might as well call the new content-type "lossless"?

[Nathan Hallquist]

I had originally gone with lossless and then changed my mind after trying nonvideo and finding myself happy with that. I forgot to change the text is all.

I am okay with either choice. I defer to you.

[Antoine Martin]

The part adding an env var for specifying content type definitions was merged in r21302 (see ticket:1950#comment:8).
r21303 disables video encoders for windows with the "text" content-type hint.

@nathan_lstc: does this work OK for you? if so, please close.

[Nathan Hallquist]

This is great! Thank you.