Let’s see if EDL and MLT have the same definition of in and out to account for the extra frames…
Let’s say we’re looking at a video with ten frames. Shotcut will number them 0 through 9.
If an edit says In=3 and Out=7, then it means the eighth frame (zero-based index 7) will be the last frame shown on screen, and the cut clip with have a total of 5 frames (counting 3 to 7 inclusive).
Is this the same understanding of In and Out that the EDL file and the EDL-to-MLT translator have?
And yes, I see your point about 30 fps NDF timing with DF notation. Shotcut tries to be frame rate agnostic by translating many things into milliseconds where possible. This allows clips with differing frame rates to be mixed on the same timeline without preprocessing. So it wouldn’t surprise me if what we’re seeing isn’t formal timecode, but rather an elapsed time reference with the resolution of the defined Video Mode. If that ends up being true, then unfortunately, it won’t be intuitive to translate the “timecode” seen in the playlist to exact frames in the source for confirmation.