For some time I have been having a problem with getting a single frame that pixelates in the middle of a dissolve, when the project is burned to DVD. It also happens sometimes when I set a chapter point, as the disc plays past the chapter point, the same pixelating effect can be seen.

It only seems to happen when the project I am putting on the DVD is a long one and the bit rate is low. Typically about 2 hours on one disc. I have tried fusing the sequence over the dissolve, but it still does it. The project plays perfectly from the timeline, it is only when it is burned to DVD that the pixelating occurs.

Any ideas please?

Stephen,

Your profile indicates that you are currently on AL 7.1 SP1, is this correct?  I would suggest updating to the 7.2 release to see if this addresses your issues.

Finally, what bit rate are you using for your DVD?

Dave

Liquid uses a 1-pass VBR encoder, and you're seeing the limitations. The only way to fix it is to increase the bitrate or move to a different encoder and authoring software.

I use CCE Basic from CinemaCraft for multi-pass MPEG-2 encoding and DVDLab pro from MediaChance for DVD Authoring. There's been enough stuff published about these (and other similar products) on the Avid forums that you can do a search there for as much gory detail as you could want.

I regularly am required to put more than 2 hrs on a disc and do not have issues. I have gone up to 2 hrs and 40min with great looking results. I think there must be something else. Are you using Liquid to output to DVD or just to make your MPEG files. Are you using Dolby? I am on 7.2 so aybe updating will help........Try it you'll like it..........Edd

I would agree. I have made some really long DVD's and they look excellent right out of Liquid.

smithe1:

I regularly am required to put more than 2 hrs on a disc and do not have issues.

It all depends on the material. Fast high-contrast movement does not encode well at low bitrates. A 1-pass encoder has to make a guess as to where bits should be allocated, and if it gets it wrong then you have pixelation. 

Since there are render engine differences, going to 7.2 is a good idea. While there's no guarantee that it will fix this particular issue, it won't hurt and it may help. At worst you get a generally better render engine and a bunch of bug fixes. 

Good points Dave. Lets ask this then, what are you outputting ie what type of project wedding, dancing, soccer, racing maybe having more details will point us in the right direction. I just did a 2 hr 35min dance recital with 2 cameras and major color correction and it looks beautiful. So how long is it actually?......Edd

It's a good question. I can tell you that in trying to transfer the original Star Wars trilogy from laserdisc to DVD, that even at the highest average and max, bitrates I could use, the lightsaber duels (and in particular the battle on Hoth) were all really pixelated (note: this was tried on Liquid 6.1). However, other reasonable fast moving objects weren't pixelated. I understand the technical details of why (I'm reasonably conversant with the algorithms involved with MPEG-2 encoding), and things like a lightsaber are probably the worst-case examples.

From what the original posting said, it's only 1 section that's giving him problems.