You have a mp4 video but you are loosing a lot of quality when posting it on youtube ?
I met this problems and it slowed me during 2 weeks.
Follow this :
1. record with obs or xplit find a tutorial on the net, set the parameters in 16:9 widescreen, 1920x1280
2. Output file : mp4
3. To edit it, use a software that allows mp4 files (movie maker coming from windows essentials or the online youtube video editor for instance). Do not convert it into an AVI file (lack of quality).
4. When your video is finished, follow this https://support.google.com/youtube/answer/1722171?hl=en-GB
5. If you have Mozilla firefox, you will probably have some issues --> take google chrome or enable MSE in Firefox : http://www.ghacks.net/2014/05/10/enable-media-source-extensions-firefox/
To enable MSE in Firefox, do the following:
Type about:config into the web browser's address bar and hit enter.
Confirm that you will be careful if a warning message is displayed.
Search for media.mediasource.enabled and double-click the name.
This sets the preference to true and enables Media Source Extensions in Firefox. YouTube will pick up on that automatically, as will other sites such as the HTML5 Test website.
6. Now you can upload it on youtube in 720p HD