Create a handy way to set a ffmpeg log handler.

[xd009642]

I'm working out this in my current project with the aim of using tracing but essentially this would let a use provide a lambda callback and handle getting it into av_log_set_callback. If I get it working in my project I'll aim to make something more generic and PR it if it could be useful for others

[jwiesler]

Hey, I forked the sys crate and the ffmpeg-next crate and merged most of the current merge requests of both crates. If you have no problem with using a non crates.io crate, you can use this one. I will keep merging pull requests because these repositories seem mostly abandonded.

I build something just like you and added basic log callback functions to my crate version. To do or use something dynamic in log callbacks you will have to use statics and probably synchronization which is way too specific for such a crate imo.

[zardini123]

I am interested in something like this as well. Current version of ffmpeg_next doesn't have this. @jwiesler has a PR for this in #91 but would have to be updated to merge into the current codebase.

[jwiesler]

The master branch of my fork of the repo is up to date with this one (I have a rebase bot set up). If you want you can either use that or update the MR to include the diff from my fork.

However, since noone ever even looked at my PR I'm not too keen of putting more work into it.