CINELERRA-GG supports the simultaneous presence in the Timeline of sources with different frame sizes and frame rates. However, audio/video synchronization problems may occur due to their different timing.1Plugins that rely on the timing of each frame, for example Motion and Interpolate plugins, may have problems when used at the same time with engines which increase frame rate. Frame rate per definition cannot be increased without either duplicating some frames or generating them in some intelligent way. But to work reliably, the Motion plugin requires access to all actual frames. These kinds of plugins (and also the rare cases of audio/video desync) explicitly require the Play every frame option.
There is no problem as long as the source fps, project fps, and destination fps are identical. In most cases, high frame rates such as 120 or 144 or any fps, will be just fine for Motion provided that source footage all has the same frame rate.
But when project and source frame rates are different (or project and rendered fps), then the CINELERRA-GG engine has to either duplicate (interpolate) some frames or throw some away. Because of this, the audio tracks and the timeline get out of sync with such accelerated (or slowed down) video. And to make Motion plugins reliably calculate interframe changes, you have to ensure the consistent frame numbers and frame properties.
Generally, best practice is to perform the following sequence of preparations for video editing.
CINELERRA-GG does not have color management , but we can still give some general advice on how to set color spaces:
→ monitor: rec709 (we get a correct color reproduction)
source: rec709 → monitor: sRGB (we get slightly faded colors)
source: rec709 → monitor: DCI-P3 (we get over-saturated colors)
These are only metadata that do not affect rendering but when the file is read by a player later they are used to reproduce the colors without errors.
For more tips on how CINELERRA-GG processes colors on the timeline see Color Space and Color Range Affecting Playback and Automatic "Best Model" Media Load.