Monday, June 28, 2004

Video Compression

I'm in the process of changing my video capture setup. While attempting to clean up some old Anime tapes that I had captured off of the TV, I'm having trouble with mosquito noise (or at least, what I think is termed mosquito noise) around the pen/pencil lines (e.g. the outline of a figure). I think it might be from using PicVideo's MJPEG codec, as it sort of looks like something that JPEG images do.

So I've downloaded the HuffYUV codec, which is a lossless codec, figuring that I could put up with the additional storage space required as compared to the MJPEG codec. Hah! For this particular tape (a noisy VHS source), HuffYUV actually compresses better, without any loss, then MJPEG at Q20. Whether or not it works that well on regular TV, I haven't tested that yet.

For a 704x480 NTSC feed, the data rate was only around 8MB/s for HuffYUV using YUY2 (4.85GB for 10 minutes), while MJPEG Q20 YUY2 is around 9MB/s (5.36GB for 10 minutes). That's 29GB/hr for HuffYUV and 32GB/hr for MJPEG Q20. Uncompressed 704x480 NTSC 48kHz 16bit stereo is around 67GB/hr.

However, I'm giving up on 704x480 and switching back to 720x480 for all of my footage. The additional space savings of Huffyuv means that it'll end up taking the same amount of working space as 704x480 using MJPEG. Plus, using 720x480 for everything means that I can combine clips easier into a single chapter (even if I start using DV instead of analog).

posted by Wuphon's at 3:01 PM