VEGAS Pro 15 has a new decoder, so4compoundplug.dll that handles AVC files in builds 177 & 216. I think the intention is that it will also handle m2ts and perhaps other formats in the future.
The benefits of this new decoder include:
- Decodes Panasonic GH5 10-bit 422 footage
- Decodes JVC YUV 4:2:2 footage
- Decodes iPhone/iPad footage (without requiring Quicktime)
- (I guess) Scope for improved GPU acceleration
However some issues are attributed to this new decoder:
- Much lower fps playback of some AVC files including some GoPro, DJI & Xiaomi Yi files
- Slow rendering of video event thumbnails for those files
- Garbled audio decoding (also here)
- Stereo audio decodes as dual mono
- Slower opening of large projects containing many AVC files (Edit: Largely fixed in VP15 build 216)
If you have any such issues, or any other issues with AVC behavior in VP15 that you did not experience in VP14 then first check which decoder plugin is by looking at the "Plug-In" section at the bottom of the VEGAS file Properties window (accessed by right-clicking on a file in the VEGAS Explorer window then choosing "Properties", or right-clicking on a video stream on the VEGAS timeline then choosing "Properties" then "General" tab):
If the troublesome files are getting decoded by so4compoundplug.dll then you can try disabling it as follows:
- Hold down the SHIFT key while opening Options > Preferences
- Click the Internal tab
- In the field "Show only pref containing:" file type "So4" without the quotes
- Set "Enable So4 Compound Reader for AVC/M2TS" to FALSE.
- OK > Restart
Bear in mind:
- This may break some of the new support such as iPhone and 10-bit 422 GH5 files, and that the bugs with so4compoundplug.dll will probably be fixed in future updates, so don't forget that you've set this because you'll probably want to un-set it in the future!
- Your audio waveform previews (stored in .sfk files) will be rebuilt when the codec is disabled or re-enabled, which may make it appear that your projects are opening more slowly. But once the waveforms are re-built, projects will open more quickly.