As streaming video has become the new standard for video distribution, we’ve been hearing a lot of complaints about interlacing from our clients. Historically, interlacing had its place, but it’s pretty distracting on today’s modern progressive 4K and HDTVs, computer monitors and mobile devices.
The big streaming providers—Netflix, Amazon, and iTunes—are all known for rejecting footage where interlacing is present or at least making you work to account for it. This is most common on documentaries where archival interlaced footage is placed repeatedly on a progressive track in between progressive HD interviews.
It’s also common on sports-related work where broadcast game footage is mingled with interviews that are progressive and usually of a different frame rate.
So what do you do about this?
If you’re an editor, it’s always best to get it right the first time. Deal with the differences in footage externally from the editing program and deinterlace the footage first. If a frame rate conversion is also necessary to match the specs of your editing track, do that at the same time using either a hardware converter or a good software-based technique.
Then edit away and most of the problems will be solved.
If you’re in the “Post-Post Production World” like we are, then you’re dealing with interlacing after-the-fact and still getting clients complaining about it (and possibly not realizing that you didn’t cause the problem). Fortunately there are still ways to correct this.
Go Back to the Source
First of all, even if it was deinterlaced in the editing process, it’s quite possible that the filter used did a poor job and pixelation or scaled up interlacing are still present. In some of these cases the interlaced footage might have started off life as progressive (24p video) or even film, which by its very nature is progressive. In many of these cases, you can go back to your source, inverse telecine the footage and bring it into your editing timeline.
Do it by Hand!
If it’s just a hot mess with interlacing in and out of the documentary, parts looking good, parts looking bad, interlacing present in certain scenes, frame blending obvious to anyone without broken glasses, then you’ve got a bigger problem on your hands. The only way to fix this type of footage is to dig in on a scene-by-scene or even a frame-by-fame bases to conform each scene. Further problems include cross dissolves over two different scenes of different formats or progressive elements and/or text that was put over the interlaced footage in the editing process. In cases like these you sometimes need to go as far as to manually hand adjust parts of a frame with different techniques to achieve the smoothest, least pixelated frame.
You do not have to settle for interlacing in your film or QC houses rejecting your movie. With the right techniques, we can all move into the progressive world!