The recommended way to make DVD files is to encode the MPEG2 and AC3 files in Vegas. You adjust your bitrate to get the desired file size so that you don't exceed the DVD size.

It now says:

Estimated size: 4,387.3 MB {94.0 % of 4.700 GB media}

Default Video bitrate {MBps}: 5.596

Does this mean it wall all easily fit?

Well, since 94% is less than 100%, I'd say the answer is yes. ;)

A few things you need to understand:

1. DVDs don't care about "hours." They only care about bits (kilobits, megabits, and gigabits). A standard, single layer DVD holds 4.7 gigabits. How much "time" fits on a disc depends on two things: how much time is in that video and how many bits the encoder dedicates to each second in that video (this is called the bit rate). To put two hours of video on a DVD, it should be encoded at about an average of 4.5Mb/sec. To put an hour of video on a DVD, the bitrate could be bumped up to 9Mb/sec. (Theoretically, anyhow. Some players have issues playing burned DVDs encoded that high, but that's another topic altogether.)

2. As for AVI being "bigger than WMV," that depends on the bitrate. If I encode the same video as a 2Mb/sec AVI and a 3Mb/sec WMV, then no, the AVI will not be bigger. While there are formats and codecs that one will generally encode at a particular range of bitrates (people generally use low bitrates for Divx AVIs, high bitrates for MPG2s), they're not necessarily limited to them. In addition, there are several, if not dozens of different codecs that can be contained by an AVI, so even these standard bitrate ranges will vary depending on whether it's a Divx AVI, a DV AVI, or whatever.

3. Everything I said in #2 is moot when authoring DVDs since DVDs use MPEG2. Period. By the time your DVD is finished, your AVI and WMV files have been re-encoded as MPEG2 using either the default project bitrate (generally 8Mb/sec) or one you specify (for example, by using the Fit to Disc option).

4. Keep in mind that re-encoding a video that's already been through a decent amount of compression (those WMV files, for example) is going to result in a loss in quality. If you can, create or obtain those videos as DVD compliant MPEG2 files before you even open up DVD Architect. But I suspect that the original format of these files is not under your control...

Rob

PS: At 94%, I'd say it will probably fit. You have to give some leeway to allow for DVDA's estimate to be a little off (though it's usually pretty generous). Also, when errors on a DVD occur, they generally occur near the outer edge of the disc, so it might not be a bad idea to bump that bitrate down a bit so as to stay away from the edge. Test it out first on a DVD-RW if you've got one.

DVDA is notorious for over estimating the file size. Have you tried ignoring the 'too big' message and burning anyway?

How do I bump down the bit rate?

In Optimize DVD, you can either select Fit to Disk or you can manually reduce the bitrate/quality level.

I think there are several issues at play here. I am currently working on a set of 28 M2TS files rendered as 1920x1080 Blu-Ray output from Vegas. The total size of the files is 24.2GB.

I'm trying to used DVDAS5 to turn these into a single-layer Blu-Ray disk, but right now I can't because DVDAS says they won't fit onto a standard 25GB Blu-Ray disk.

Since 24.2 is less than 25 I am assuming that DVDAS is counting the space required for the menus I have created, the Blu-Ray file structure, and whatever other overhead is needed to make a complete Blu-Ray title.

A key issue here is the bitrate at which the input files are encoded on the disk. Since my input is 1920x1080 DVDAS defaults to no re-encoding. But this can be changed in Project Properties.

My project's default bitrate is 15MB/sec. By changing this to 11MB/sec and specifying that the 8 largest M2TS files be re-encoded at that rate I got the overall size of the entire project to be 23.2GB (according to DVDAS.) But when I started to build the ISO image DVDAS reported it would take 17 hours to render.

This is not reasonable (at least for me) so I have gone back to re-editing my input files and shortening them. I will do this until I get a set of input files (input to DVDAS, output from Vegas) that allows DVDAS to create the ISO file with no re-encodingat all and all bitrates at the default 15Mbps.

As has been stated elsewhere, there are only 2 parameters that count here: the total number of bits in the final video (ISO file) and the rate at which these bits are read (the bitrate.)

You can't put more bits on the disk than it will hold, so that limits the overall size of your video. If you have too many bits (too much video) you can reduce the number of bits on the disk by (1) eliminating some video or (2) lowering the resolution of the rendered image.

You can also reduce the number of bits by reducing the bitrate of any/all of the video clips. Doing this will decrease the resulting video quality, but the relationship between bitrate and quality is not clear to me. I've seen some statements that 1920x1080 needs to be at least 15Mbps. It would be nice if there was a utility program that would tell you the bitrate of a disk that was playing. I'd like to know the bitrate of commercial Blu-Ray and DVD disks.

I think there are several issues at play here. I am currently working on a set of 28 M2TS files rendered as 1920x1080 Blu-Ray output from Vegas. The total size of the files is 24.2GB. ... I'm trying to used DVDAS5 to turn these into a single-layer Blu-Ray disk, but right now I can't because DVDAS says they won't fit onto a standard 25GB Blu-Ray disk. ... I have gone back to re-editing my input files and shortening them.

If you get to the point where you'd have to edit out things that you really want to keep in, you should investigate DVD Shrink and similar products. At least with DVDs, that program would allow you to "squeeze" prepared files without having to re-encode them. I have no idea if DVD Shrink has kept up with the times and will do Blu-ray projects or not. If not, maybe there's something else out there that will do for Blu-ray what it did for DVDs.

Rob

I'm trying to used DVDAS5 to turn these into a single-layer Blu-Ray disk, but right now I can't because DVDAS says they won't fit onto a standard 25GB Blu-Ray disk.

Did you actually try building the ISO file? I ask only because, at least in the case of DVDs DVDA is notorious for over-estimating the space required.

As has been stated elsewhere, there are only 2 parameters that count here: the total number of bits in the final video (ISO file) and the rate at which these bits are read (the bitrate.)

I think this is not quite right. The two parameters are the time and the bitrate. These determine the number of bits that need to be fitted onto the disc.

If you have too many bits (too much video) you can reduce the number of bits on the disk by (1) eliminating some video or (2) lowering the resolution of the rendered image.

I think that should be (1) eliminating some video or (2) lowering the bitrate. Reducing resolution will reduce quality in a different way from just reducing the bitrate.

The "overestimate" problem usually manifests itself in the number in the lower right corner of the interface. It happens because DVDA is guessing how much the prepared files are going to be before it's actually prepared them.

Once DVDA starts saying "you don't have room on the disc for that," it's already done the prepare and is just comparing the size of the prepared files with the amount of space available on the media. As a result, this particular error message is generally accurate (unless the user just hasn't selected the proper media type).

Rob

Once DVDA starts saying "you don't have room on the disc for that," it's already done the prepare and is just comparing the size of the prepared files with the amount of space available on the media.

The message I was referring to reads; "The estimated size of the project is larger than the default space available on media." It appears on the second dialogue of the Prepare wizard, before preparation takes place. It doesn't always tell the truth.