I had some footage given to me by a client to use in an edit and it appeared to be interlaced (i.e. I could see those awful horizontal lines whenever there was movement). The files were .mp4 so I used mpeg streamclip to transcode them to Apple Pro Res 422 for editing in FCP 7 and checked the 'deinterlace' box to hopefully solve the problem.
It didn't solve the problem, the lines were still there on the 422 render.
I've tried using the FCP 'de-interlace' effect on the clips - still no good, lines still there on final render.
I have taken the original .mp4 into FCP and looked at the properties and under 'Field Dominance' it says 'none'. I assume that the clips didn't come out of the camera as .mp4 so does this mean that the clips I've been given have been compressed to progressive mp4 without being de-interlaced and the lines are therefore embedded on a progressive video?
Am I missing something else or do I need to try to get the original camera rushes to solve the problem?
It sounds to me as if the issue may be that the clip is being misinterpreted as progressive, so the answer is not to deinterlace, but rather to put the clip on a new timeline with the proper field order (upper/lower) set in Sequence Settings before adding the clip to the timeline, as you cannot change the seq settings once there are clips on the timeline.
If the above does display the clip correctly, then export the clip as a self contained QT, and it should have the proper field order.
David Roth Weiss
David Weiss Productions
David is a Creative COW contributing editor and a forum host of the Apple Final Cut Pro forum.