From Avisynth wiki
Interleaved image format is a format for storing images where all color components needed to represent a pixel are placed at the same place in memory. This is in contrast with how planar images are stored in memory.
- Supported interleaved formats in AviSynth 2.5/2.6: RGB24, RGB32, YUY2
- Supported interleaved formats in AviSynth+: RGB24, RGB32, RGB48, RGB64, YUY2