I-Frame pulsing in HCenc

[um3k]

I'm trying to encode a video for DVD in HCenc, but I keep having problems with I-frame pulsing. I've tried several different matrices with little or no improvement, so I think the problem must lie with one of my other settings. The source is uncompressed, downscaled from edited HDV. It is fairly noisy in some parts, which makes the pulsing more noticeable, but it can be seen on clean frames, as well.

If someone can suggest a way to improve my encode, I would be very grateful. I want this film to be as high quality as I can get it.

Here is my HC.ini:

*BITRATE 7950
*MAXBITRATE 9000
*FRAMES 0 105168
*PROFILE best
*GOP 12 0
*PROGRESSIVE
*AVSMEMORY 128
*PULLDOWN
*INTRAVLC 2
*MATRIX mpeg
*LUMGAIN 3

[Mug Funky]

*GOP 12 0

that 0 means no b-frames. you should probably make that a 2.

it could well be that the p-frames are having to take one for the team because of a lack of (more efficient) b-frames. the i-frames in this case would provide noticeable quality jolts.

[um3k]

I have a feeling you nailed it. Gonna try a test encode right now. Now I wonder, how the heck did I mess that one up? I must've been experimenting or something and forgot to set it back. Thanks, I'll let you know how it turns out!

EDIT: Thank you! The problem was exactly as you suggested, setting B-frames made a huge improvement. I probably would've figured it out eventually, but who knows how long it would've been before I looked at the B-frame settings!