VEGAS Pro 15 has a new decoder, so4compoundplug.dll that reads AVC and XAVC-S files. 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 AVC footage
- Decodes JVC YUV 4:2:2 AVC footage
- Decodes iPhone/iPad AVC footage (without requiring Quicktime)
- (I guess) Scope for improved performance
However some negative issues are attributed to this new decoder. In particular:
- XAVC-S slow loading and high RAM usage
- Stereo audio decodes as dual mono (e.g. Nvidia ShadowPlay)
If you experience 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 being used 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
With luck, VEGAS will now instead attempt to use an alternative decoder such as compoundplug.dll to decode your files, which may solve the issue.
Bear in mind:
- This may break some of the new format support such as iPhone and 10-bit 422 GH5 files, and that the bugs with so4compoundplug 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.
Note that in VEGAS Pro 15 builds before 261, more formats were decoded by so4compoundplug, and this caused the following issues:
- 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)
- Slower opening of large projects containing many AVC files (Largely fixed in VP15 build 216)
Edit 1st December 2017: In VEGAS Pro 15 build 261, troublesome GoPro, DJI and Xiaomi Yi formats have been put on a new "blacklist" that makes them fall back by default to opening with the compoundplug decoder, which generally works very well with these formats. Read the thread for the full story...
Edit 6th June 2018: In VEGAS Pro 15 build 361, the blacklist was made into a separate, editable xml file. In this build the file needs to be moved in order for it to work. Other formats such as XAVC-S can also be added to the blacklist if necessary by editing the file (with great care). Full details in this post.
Edit 3rd September 2018: From VEGAS Pro 15 build 384, so4_blacklist_vp15.xml is placed by default in C:\Program Files\VEGAS\VEGAS Pro 1X.0\ where it can be read, so there is no longer any need to move it.