Render 1080/60p video to DVD?

[Dave Haynie]

A little perspective here: 1080/60p video contains about 12 times as much information as anything that’ll fit on DVD. You have 1920×1080 at 60 frames per second. An NTSC DVD can have a maximum resolution of 720×480 at 60fps interlaced, or 24fps progressive. That’s your choice… DVDs are standard definition. DVD-class standard definition is going to look very, very soft compared to the better-than-Blu-ray quality video you get from 1080/60p.

-Dave

[John Rofrano]

[Casey Menninger] “1. How exactly does one set the Project Settings? To match the source footage? If yes, I do not see a setting in the drop down menu that matches 1080/60p. What should I choose? “

The easiest way is to use the Match Media Settings button:

[Casey Menninger] “2. If I pick “MainConcept MPEG2” as my “type” of file, which template do I choose, DVD Architect Widescreen?”

Yes, and since you want to render progressive, you want the DVD Architect 24p NTSC Widescreen video stream template for your video and then render your audio separately as Dolby Digital AC3 Pro.

[Casey Menninger] “3. I would be correct to assume that rendering my final product as progressive scan is desirable?”

Yes, but the only progressive frame rate that is supported by DVD is 24p.

[Casey Menninger] “4. I did a test render using the above and my best guesses, and the very sharp original footage was rendered a tad soft? Is that normal for going from 1080/60p to NTSC DVD(mpeg)? If not, what kind of suggestions do folks have? Unsharp Mask?”

What you are probably seeing is frame blending as Vegas merges your 60fps into 29.97fps. What you should try is right-clicking each event and select Disable resample. This will tell Vegas to drop frames instead of blending them. It will simply throw away every other frame to bring your 60fps down to 30fps.

[Casey Menninger] “5. Finally, there may be some additional footage down-the-line that I might acquire. If I save the original video footage as DV “Video for Windows (AVI)” and THEN choose to subsequently render it to MPEG for the DVD, will I have degraded the original’s quality any more than a straight MPEG conversion from the source?”

Yes. Any render to/from a lossy format will degrade quality some. In addition, you will be tossing away a lot of color information because AVCHD is 4:2:0 and DV is 4:1:1 so your resulting video will be 4:1:0!!! I would not render to DV if you want the best quality. Go straight from your AVCHD source to your final MPEG2 which is also 4:2:0.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Casey Menninger]

Hi Guys,

Thanks for the help and tips!

John, I already tried your advice (disable resample) and I saw a notable increase in clarity in the final MPEG — thanks!

Under File, and Properties, I was able to successfully “match” the video properties of the original file. I did not know about that feature…

I applied the source properties to my project as noted above, and chose best for full-res rendering quality. What do I do under Project, under the custom settings of the rendering window? Usually, I check “Best” quality, but because of the aforementioned match, should I leave it at “use project settings”?

Somehow, I did not know you could make a 24 frame NTSC DVD. I thought that was the frame rate for PAL. Assuming the source is progressive, it is indeed better to render as 24p as opposed to 60i (using the top parameters that Dave mentioned in his post)? I always have flickering issues with interlaced footage. 24p will play alright on NTSC DVD players?

Finally, if I use AC3 audio, how far up can I pump the max and average bit rate in VBR for MPEG rendering?

Thanks again guys for your expertise…!!!

[John Rofrano]

[Casey Menninger] “What do I do under Project, under the custom settings of the rendering window? Usually, I check “Best” quality, but because of the aforementioned match, should I leave it at “use project settings”?”

I usually leave it at project so that it can be controlled at the project level. Some projects you’ll only need to use the Good setting while others you may want Best. This avoids having to edit the template each time.

[Casey Menninger] “Somehow, I did not know you could make a 24 frame NTSC DVD. I thought that was the frame rate for PAL. “

No, the frame rate for PAL is 25fps. Since each frame is two interlaced fields it is sometimes expressed as 50i.

[Casey Menninger] “Assuming the source is progressive, it is indeed better to render as 24p as opposed to 60i (using the top parameters that Dave mentioned in his post)? I always have flickering issues with interlaced footage. 24p will play alright on NTSC DVD players? “

What actually happens during rendering of 24p, is extra frames are added (called “pulldown”) to bring it up to the 29.97fps NTSC standard. But it’s still progressive which is what you want.

[Casey Menninger] “Finally, if I use AC3 audio, how far up can I pump the max and average bit rate in VBR for MPEG rendering? “

The max VBR doesn’t change. DVD’s top out at about 9Mbps. Anything higher and you risk the disc not playing.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Stephen Mann]

“…even though I knew the final product would be put on a NTSC DVD, I opted for the higher quality setting…”

This is the correct workflow. Shoot and edit in the highest quality possible and only downconvert at the last possible moment. In this case when you encode (“Render As”) the MPEG2 file for the DVD.

At a later date, all you need to do to make a Blu-Ray disc is to re-encode the project for Blu-Ray.

Steve Mann
MannMade Digital Video
http://www.mmdv.com

[Dave Haynie]

[Casey Menninger] “Somehow, I did not know you could make a 24 frame NTSC DVD. I thought that was the frame rate for PAL.

[video_geek_mode]
Nope. PAL does fields at 50Hz, frames at 25Hz. This goes back to the dawn of AC Power… in the USA, AC power was first pushed by Nikola Tesla, as the best means of power distribution. The key was that by using alternating current, Tesla (backed by Westinghouse in the USA, several other companies in Europe, versus Thomas Edison who backed DC power) could use his newly developed transformer, to send power long distances at very, very high voltages (power loss over wires is proportional to current, not voltage… a transformer can trade off high voltage/low current for low voltage/high current).

So power at the wall changes direction at some rate… alternating current. In the USA, it was done at 60Hz… Tesla came up with the 60Hz and three-phase 220V power (split to most outlets to 60Hz 110V single phase) we still use today… he determined 60Hz transmissions would be more efficient. In Europe, German firm AEG became a near monopoly in power generation, and set their cycle to 50Hz, claiming it better fit metric standards (one of the few instances of stupidity around the generally superior metric system). They were originally 110V, but given that 50Hz is about 20% less efficient to generate and 10% lossier in transmissions, they boosted the power to 220V single phase/440V dual phase.

So enter TV. The television inventors, here and in Europe, recognized that electric lights actually do flicker, though too fast for your eye to usually see. However, this flicker would create a visible beat frequency against any video display of a different (and particularly, lower) frame rate… particularly given the way CRTs worked, counting on the persistance of phosphors. So the USA set their field rate to 60fps, their frame rate to 30fps (interlacing was needed to keep the signal relatively small), Europe to 50fps fields and 25fps frames.

With the advent of color TV, NTSC was tweaked to a 29.97fps frame rate. This kept the added color signal out of phase with the audio signal. The NTSC color signal actually gets very close to the space reserved for the audio signal, as well as mucking around with the luma signal, so, particularly in the days before multi-line motion adaptive comb filters, they put in a couple of magic tricks like this to make it easier to break the signal apart in the TV. But anyone who remebers the good old days of analog TV will recall how easily a slightly mistuned channel put video noise into the audio.
[/video_geek_mode]

[Casey Menninger]
Assuming the source is progressive, it is indeed better to render as 24p as opposed to 60i (using the top parameters that Dave mentioned in his post)? I always have flickering issues with interlaced footage. 24p will play alright on NTSC DVD players? “

I think some of the other guys covered this pretty well, but basically, it’s your choice. NTSC DVDs support 480/60i or 480/24p only. From your 1080/60p video, you can encode to 480/24p, but there’s going to be some frame blending or uneven frame dropping to deliver the proper 24p cadence. You can also render directly to 480/60i, which if done correctly will map 60p fields to 60i frames with no interpolation. Or you can drop every other 60p frame, and essentially create a 30p result packaged as 60i. This will play as 60i on any old TV, but a modern television nearly always does full field to frame conversion (if for not other reason than most modern displays, like LCD and DLP, cannot actually do interlacing), so this may look like real 30p playback on most displays (this is more commonly used for 1080/30p video put on Blu-ray, but it’s the same “trick”).

Which is correct? Depends on the material.

The 24p encoding for DVD is also called NTSCfilm… it’s really 23.976 fps, or something like that. The goal was to enable the best possible movie film encoding, based on the 24fps standard used for film.

This is very similar to the “24p in a 60i wrapper” some HD camcorders use for their 24p mode. What actually goes on disc is the 24fps run through a very specific cadence of 3:2 pulldown. For smart devices that can do something cool with 24p, the player knows which fields to toss out to reconstruct a proper 24p. For players less skilled in the art of playback, the video can be played at plain old 60i, and it looks line any other film telecined for TV use. This is and has always been part of the DVD spec.

To produce DVD compliant 24p, use the “DVD Architect 24p” or “DVD Architect 24p Widescreen” presets in Vegas.

[Casey Menninger]
Finally, if I use AC3 audio, how far up can I pump the max and average bit rate in VBR for MPEG rendering?

The total raw bitrate for DVD is 11.08Mb/s. There’s about 1Mb/s of encoding overhead in this, leaving 10.08Mb/s to work with. Of that, some is reserved for subtitles, leaving a maximum rate of 9.80Mb/s for the combined audio and video track. If you’re encoding multiple angle video, the maxium bitrate becomes 8.0Mb/s per angle. Typical audio in AC-3 is 192kb/s for stereo, 448kb/s for 5.1 surround, leaving 9.32Mb/s for video without having to worry about your audio track.

Of course, at this rate, you’re going to fit just over an hour’s worth of video on a DVD5, or two hours on a DVD9… in practice, less if you have other things on the disc (menus, etc). Plus, it’s rarely necessary to encode at full possible speed to get the best out of your video. I recommend a variable bitrate, but that’s also often necessary just to fit your project in the space available on disc.

It’s less of an issue today, but realize that some older players may not really support full speed video, at least on DVD-R. No real excuses, just lazy engineering far as I can tell. But another argument to back off a bit. There may also be a few players out there (PCs, PS3s, BD players) that would handle a slight higher rate just fine, if your software permitted it. But that would fail outright on most dedicated players.

-Dave