Preparing Assets - DVD From Scratch

[FreQi]

For a couple years now, I have been capturing/encoding tv shows to DivX/XviD, and recently I've started encoding HDTV sources as well. I've come to a point where I am interested in encoding the material to go straight to DVD-Video rather than mpeg4, so I began investigating what is involved. Below is a list of what I believe to be true about preparing assets for creating an NTSC DVD-Video Disc that will contain multiple episodes of television shows.

Please note that I have not successfully completed making a disc at this point and I post this only to confirm my assumptions so that I may be sure I am moving along in the right path.

Software

This is a list of all the software I am using or have tried along the way, so when I mention it below, you'll know what exactly I used.

VirtualDubMod_1_4_13_2v2
DVD2AVI 1.83 (trbarry's special hdtv build)
AVISynth 2.51 (Decomb.dll, BT709ToBT601.dll, MPEG2DEC3.dll)
BeSplit v0.82
BeSweet v1.4 (with azid.dll v1.8)
CCE SP v2.66
pulldown.exe v0.99d
Scenarist v2.7.0.0241
Sonic Foundry Soft Encode - Dolby Digital 5.1 -- v1.0 build 19


Video

I prepared my video assets like I have been setting up any other video encode using VirtualDubMod, AVISynth, etc. The only change was the target resolution. According to digvid.info (http://www.digvid.info/media/dvd.php), there are 4 potential resolutions for NTSC DVD videos.

(1a) 720x480
(1b) 704x480
(2a) 352x480
(2b) 352x240

Since my sources are HDTV, I decided to use the largest possible resolution (1a). Since everything else was essentially treated like I would have done for an XviD, the videos are IVTC'd, yielding a frame rate of 23.976, and each frame becomes progressive scan.

I used the Doom9 CCE (http://www.doom9.org/mpg/cce-advanced.htm) guide for encoding the video with an average bitrate of 2,000k. Because the guide shows screen shots of an older version of CCE, I was king of groping around for the correct settings. Here are screen shots of what I used under settings (http://freqi.net/forums/CCE_1_settings.jpg), video (http://freqi.net/forums/CCE_2_video.jpg) and quality (http://freqi.net/forums/CCE_3_quality.jpg). This made a 22min episode approximately 300megs (without audio). I then used pulldown.exe to effect a 2:3 pulldown on the video (make the 23.976fps video fake like it's 29.97fps).

Because this is just a test run, I am not sure what file size I will be actually trying for yet, as I haven't quite figured out the next step...

Audio

Preparing Audio assets is what I am currently a bit confused on. I wanted to downsample the 3_2ch 384Kbps AC3 to a 3_0ch 256Kbps, or 2_0ch 256K, but I have been unable to bring these AC3 files into Scenarist. I get an error message saying the file is not a supported file format (the same problem dweebster had back in March (http://forum.doom9.org/showthread.php?s=&threadid=50018)). That doesn't make sense to me since AC3 is the required format... It's probably me just not understanding Scenarist.

I thought there might be a problem with the files AC3Machine was producing (as addresses in this thread (http://forum.doom9.org/showthread.php?s=&threadid=43466)), so I tried using Sonic Foundry's Soft Encode, to no avail. I also tried to simply import the full 384k AC3 file that was demuxed from the hdtv transport stream and fixed with BeSplit, but it still calls it an unsupported format.

Any suggestions on how to go about muxing my .mpv and .ac3 ?

[auenf]

Originally posted by FreQi
Audio

Preparing Audio assets is what I am currently a bit confused on. I wanted to downsample the 3_2ch 384Kbps AC3 to a 3_0ch 256Kbps, or 2_0ch 256K, but I have been unable to bring these AC3 files into Scenarist. I get an error message saying the file is not a supported file format (the same problem dweebster had back in March (http://forum.doom9.org/showthread.php?s=&threadid=50018)). That doesn't make sense to me since AC3 is the required format... It's probably me just not understanding Scenarist.

I thought there might be a problem with the files AC3Machine was producing (as addresses in this thread (http://forum.doom9.org/showthread.php?s=&threadid=43466)), so I tried using Sonic Foundry's Soft Encode, to no avail. I also tried to simply import the full 384k AC3 file that was demuxed from the hdtv transport stream and fixed with BeSplit, but it still calls it an unsupported format.

Any suggestions on how to go about muxing my .mpv and .ac3 ?

what you could do instead is decode the .ac3 to 6 mono waves and use the scenarist ac3 encode instead, which should make a compliant ac3 file.

Enf...

[FreQi]

Thanks auenf. I might end up trying that anyway since there are portions of the audio track that I would like to manipulate anyway, and I haven't found anything that will let me edit AC3 files. There's a few places that I want to mute or replace with different audio (like the end credits of a show). I thought Sonic Foundry SoftEncode would let me do that, but it seems it'll only let you change the dB and encode it to a different kind of AC3. Not a very robust application really.

I did however find that IfoEdit (v0.95) will mux m2v's and ac3's under it's DVD Author menu. So I was able to put all the files it created into a VIDEO_TS directory and drag that into PowerDVD and watch my encode. Everything looked good and sounded good, but the video plays too fast. It's a 23.976fps progressive scan video that I used Pulldown.exe to telecine it to 29.97fps interlaced. IfoEdit sees it as a 30fps video, which I'm guessing is just 29.97 rounded up for the display. After remembering that I checked the "Progressive frame" box in CCE, I decided to try muxing the pre-pulldown m2v with the same AC3, and it plays just fine. IfoEdit also sees this as a 30fps video. Tonight I am going to try re-encoding the episode without using the "Progressive frame flag" checkbox, then apply pulldown.exe to see what happens with sync. Any suggestions/opinions on pulldown.exe vs the Progressive frame flag?

[oddyseus]

Vitec Mpeg2Pro is a suite that has an app that lets u cut and join ac3 streams without renconding.