I use VEGAS Pro 16 (build 352) to edit videos from my iPhone. I have been using this FFmpeg technique to convert them from .mov files to .mp4 files.
I recently upgraded to an iPhone X and began filming in 4k instead of 1080p. However, the aforementioned technique doesn't seem to work with 4k videos.
For example, here is the media info of an iPhone 1080p video that I converted using FFmpeg.
Plug-In
Name: compoundplug.dll
Folder: C:\Program Files\VEGAS\VEGAS Pro 16.0\FileIO Plug-Ins\compoundplug
Format: AVC
Version: Version 16.0 (Build 352)
Company: MAGIX Computer Products Intl. Co.
In contrast, here is the media info of a 4k video from the same iPhone that I converted using FFmpeg.
Plug-In
Name: mxhevcplug.dll
Folder: C:\Program Files\VEGAS\VEGAS Pro 16.0\FileIO Plug-Ins\mxhevcplug
Format: Intel HEVC
Version: Version 1.0 (Build 8532)
Company: MAGIX Computer Products Intl. Co.
I used the same FFmpeg command for both conversions. Why is the plug-in different? VEGAS runs noticeably slower when I'm using the converted 4k videos.
For reference, here is the FFmpeg command that I used.
for %%a in ("*.mov") do ffmpeg -i "%%a" -vcodec copy -acodec copy "%%~na.mp4"