Being a GoPro Studio user myself for editing videos I know that GoPro takes only mp4 videos as input (Step 1) or avi videos as input at Step 2 of the conversion process. While GoPro records perfect uncompressed videos for editing in the Studio, not all video recorder are the same.
I realized this when I actually created some screen recordings of a tutorial in avi format using a third tool. Since I had put lot of efforts in recording the video I knew re-recording was not possible. Hence I had to convert the avi video into GoPro compatible Cineform mp4 or avi formats.
If you are also looking for the same, then I have explained the entire solution in the video below (step by step) if you prefer to see and skip reading.
1. Download this free utility called as MPEG Streamclip (no installation is required).
2. Open the video that you want to convert, File -> Open Files
3. Now again go to File and select your output format, File -> Export to AVI (or MPEG-4)
4. Ensure below settings for lossless and uncompressed conversion into GoPro compatible videos.
Compression as GoPro-Cine Form HD/4K/3D
Quality as 100%
Frame Size as Unscaled
Sound as Uncompressed at 48KHz.
5. Now select the “Make AVI” button at the bottom. That’s all, now you can open your converted video in GoPro Studio.
6. If the video exported is MP4 then it can be opened at Step1 and if the video is AVI then it can be opened at Step2.
Note: You can use this tool for Batch conversion too, List -> Batch List -> Add Files -> Go.