Saturday 15 February 2014

The Best 720p Lossless Codec

I've done lots of investigating into 1080p60 but I've never thoroughly looked into 720p. This article will be focused on capturing Lossless 720p from the PS3/360 as this is currently what most people will be doing.

Since a majority of the games on these systems are just 720p30 padded into 720p60, I'll limit the frame rate to 30 fps in AmaRecTV. This alone drastically cuts down on the peak bit rate by as much as 48%. I tested the three most popular codecs: x264vfw, Lagarith and UT Video. Every codec will be configured for YUY2 sampling. To keep it fair, I am also going to configure x264vfw with --keyint 1 so that editing and frame seeking are never a problem.

The Left Behind content for The Last of Us came out yesterday so I decided to use that as my source material while I played. It's the usual run around an area and record the peak bit rate and maximum CPU load. Below are my results:

720p lossless capture x264vfw lagarith ut video
Click to enlarge
If you read my 1080p60 articles, you know how much of a shock that is. Both UT Video and Lagarith trump x264vfw. Requiring that precise editing compatibility for x264vfw really hurts. Even if you completely disable --keyint and rely on P frames, the peak bit rate was still 171 Mb/s. However, we are not talking about a massive difference between any of the codecs (every single one will easily write to a USB 2 hard drive) so it's not an issue.

The CPU load of Lagarith is quite a concern. When I tested 720p60 with the same material, the CPU load went up to 43% while x264vfw went to 7% and UT Video went to 15%. If you have a really weak CPU you might want to stick to those two codecs.

Although x264vfw might not compress the best at these resolutions, the sheer configuration you can do is astounding. You can shave so much bit rate by just using a ridiculously low CRF value and you will never be able to tell the difference. For example, I set the CRF to 16 and my peak bit rate never went over 50 Mb/s. That's like a 75% bit rate reduction for virtually no visible quality loss.

So what is the best 720p lossless codec? It's not as clear cut as 1080p60 was. x264vfw is simply amazing but be warned that some editing programs (Premiere Pro in particular) won't play H264 video in an AVI container. You might want to take the CPU load hit and go for Lagarith or UT Video if you use such programs.

No comments:

Post a Comment