[ This article was first published in the November, 2009, issue of
Larry’s Final Cut Pro Newsletter. Click here to subscribe. ]
Seigo Saito, from Japan, writes:
I am exporting a ProRes 1920×1080 60i clip as a self contained movie. I then selected the 120 min. best quality preset in compressor to make my MPEG-2 and AC3 file for SD DVD. The quality is pretty bad. I get jagged edges and horizontal lines in the MPEG-2 file and all text is of poor quality.
Larry replies: Thanks for writing!
Try doing this compression in two steps, because the quality of the 120 minute setting is somewhat low. Compressionists call this “Pre-Compression,” which means to prep the file into its final format before compressing it. When you need to create multiple compressed versions of the same file, pre-processing can save a lot of time.
1. Resize your HD movie to SD using Compressor but don’t compress it.
* Encode it to ProRes HQ
* In the Frame Controls tab, turn Frame Controls On, set Output Fields to Progressive, Deinterlacing to Better, and turn Adaptive Details Off.
* In the Geometry tab set image size to 853 x 480 using a custom 16:9 aspect ratio
2. See how your movie looks. It WON’T look as good as HD, as the image resolution is seven times smaller. But it should look OK. The best approach is to work with only a short – say 20 second section – to save time until you get the settings you want.
3. Then, compress the resized image to MPEG using the DVD Best Quality 120 minutes setting.
This two-step process takes a bit longer, but should provide a lot higher quality.
4 Responses to Solving Video Compression Problems When Down-Sizing HD to SD
This explanation is great!
I searched over the web for a descent solution to this problem. All the professionals proposed things everybody would have been able to suggest and once the conclusion was that a DVD always looked bad on an HD screen. So problem Solved, they commented.
No no no! THIS here is a solution for the problem. Of course SD isn’t HD, but a DVD should be rendered to the maximum possible quality.
Thanks a lot for explaining this workflow!
I don’t quite understand how to do this. I have a ProRes file that I want to convert to SD for DVD. I’m having one problem in Compressor (using the version that came with FCP 6) – the Mpeg2 file has lines on the bottom (these lines look like they come from the top of the image). So, would this pre-compression help me or not? and do you have any thoughts about how to fix my problem? The lines do not show up in the ProRes file, only after I compress to Mpeg2.
Thanks,
best, Ellen
I tried the above, but in the Geometry tab portion (Dimensions settings), was unable to change the Frame Size (options were grayed out, and nothing would make them changeable).
My source file is ProRes 422 HQ, and I was able to change all the other settings. Thanks.
I tried this exactly and I kept getting error messages when importing the M2V asset made by Compressor into DVD Studio Pro that said “incompatible format.” Any ideas what I am doing wrong?