This week has been focused on the quality of the DVD transfer. Until last night, all of my test DVDs had disappointing quality when it came to fades and credits. There were always noticable digital artifacts on the TV that I couldn't really see while editing on the computer.

At first I thought they were a result of the MPEG conversion, which is lossy. People are familiar with this from MP3 audio files - well the "MP" stands for MPEG, they are similar standards.

But after a lot of digging around and experimenting, I found out that the quality degradation came from the way I organized my projects. Instead of editing the entire movie with one gigantic timeline, I broke each day into its own separate project. Then, I render all the clips for a given day into an intermediate AVI file, and combine all eight chapters into one timeline at the end. Then I export that to DVD.

It turns out that when I rendered the individual days, it was faster and most efficient to use the DV standard used by my MiniDV camera. That way, most of the clips didn't need to be processed much and I didn't lose any quality. However, DV is also a lossy standard, and it turns out to be pretty damn crappy for things like smooth fades and text.

For an analogy in the audio world, this is like taking pristine digital audio and then rendering it as an MP3 file, and then making a CD out of the MP3s. Basically it lowered the quality in the middle of the process.

So eventually I figured out that I need to render the individual chapters as uncompressed AVI files. The sucky thing about this is that it takes about 10 times as much disk space, and also about 20 times longer to render. Fortunately I just bought an external 160GB hard drive for rendering, and suprisingly, it's already about 90% full just from these temporary files. Unbelievable. And slow.

But it looks as good as I can possibly get. Fades are now completely smooth, and there are no weird digital artifacts flying around in the background of black credits and titles.

Fortunately I'm entirely done with editing now, so today's MPEG conversion will be the last one, unless I need to make some change that I am not aware of right now.

Hopefully the subtitles will be done in about a week, and then I can send off the DVD for replication!

Good news on the 30 frames-per-second (fps) vs. 60 fps front. I accidentally shot the first two days of footage using 60 interlaced frames per second, and the rest of the movie at 30 fps non-interlaced. The result was that the first two days looked more like home video, and the rest of the movie looked more film-like.

I have been worried about this but knew that it didn't make sense to tackle it before getting all the editing done.

Yesterday I made draft DVD #4 of the movie, and experimented with a setting that to make the 60 fps look more like the 30 fps footage. As it turns out, it worked fantastically well, so now the entire movie has a consistent look (with regard to motion anyway).

Now the big challenge is to find a bitrate setting for the MPEG video on the DVD. Previous DVD drafts used a "variable bit rate" where the compression dynamically adjusts to the scene, overall averaging around 7 megabits per second. That worked fine for most cases, but fade-ins and fade-outs looked a little chunky.

So yesterday I tried a "constant bit rate" of 7 megabits per second. This made the fade-ins look a little less grid-like but made some diagonal lines more stair-stepped and pixelated. The one big advantage of this is that it only takes half the time to make the resulting MPEG video because CBR only requires one pass, while VBR takes two passes. That cuts the rendering time from 3 hours down to 1.5.

But I think I'm going to have to go back to VBR, only this time trying higher than 7. That's the suckiest problem with working at this stage, because the files are huge and most of my time is spent waiting hours for things to render.