HDTV MPEG > DVD: does bitrate matter?

[humphrey]

Hi:

I have a few questions on burning an HDTV MPEG to DVD. FYI I searched previous posts for a while but came up with nothing relevant!

I have an HDTV MPEG with the following specs: 1280x720, 60 frames persecond, 16.8 Mbps. Using Nero Vision Express to burn to DVD.

FYI the DVD burns fine!!! HOWEVER, I do have a few questions:

1. at "high quality", Nero Vision Express burns to DVD at 9,716 Mbps. Question: is there ANY "real" benefit to burning at "high quality", given the specs of the MPEG being burned? OR ... will I get decent results burning at a lower bps rate?

2. Given the 60 FPS of the original MPEG, SHOULD I set Nero at "Progressive"?

Again, the MPEG burns to DVD just fine. I guess what I'm really asking for are any "tips" to improve the video quality (if at all possible).

Thanks!

[mikiem]

TO start with, the quality of your original is based on it's size -- it simply has an awful lot more pixels. On the downside, it also has an awful lot of pixels.

Going to DVD, you're tossing most of them [pixels] out, so it just becomes a high quality DVD source file, to be treated as any other DVD really. Think you might find something like V/Dub may do the resize better, and there's definitely better compressors -- sure you'll recieve a lot of tips on that end of things. (FWIW I like Mainconcept).

RE: Bitrate, the idea is use the least compression possible that will produce a file small enough to burn. The higher the bitrate, the less the compression. Compressing a video tosses out data, the more compression you use, the less data you wind up with. The less data you have, the worse the picture looks.

RE: fps etc... If you've got 60 fps progressive, it's probably already been downsampled to 29.976 by Nero (there are several utilities to verify). At any rate, depending on the source of your source, probably want to encode to mpg2 as progressive, though might not notice a huge difference.

[kschang]

If you want HD, you should have converted to H.264/AVC1 codec. Those are the acknowledged "HD" formats. DVD is just 720x480 (NTSC spec).

[guns1inger]

If you want to keep the best quality you can while still going to the DVD format, don't use Nero, use a good quality mpeg-2 encoder. Tmpgenc (HQ/slow/$), CCE (HQ/fast/$$), ProCoder(HQ/not quite as fast as CCE/$$), HCEnc (HQ/slower than ProCoder/free) are all much better than nero vision, and give you a great deal of control over passes, bitrate etc. Use avisynth to filter (resize etc) before passing through to the encoder for maximum quality.

If you aren't prepared to go to this length (which isn't much once you have done it a couple of times) then quality isn't the main aim.

[whitejremiah]

yea, nero really has gotta stop throwing all sorts of other junk into their cd burning programs.....i dunno about anyone else, but i use nero to burn discs..thats it. i dont need any of this very much mangled audio encoding (which is no good, btw) video encoding (x.264 is a better codec than that nero codec, and it's free) mpeg 2 encoding....well that was just discussed...keep it simple, burn a disc, thats all it was made for, and thats all it SHOULD do...i know some people are gonna argue me on it, too.....but honestly, even throw say windows xp out there.....there's better file compressors out there (7-zip anyone) better media players out there (zoom player, BS player, MPC, VLC, ect...) none of that crap was honestly needed to be included, i think software companies should start offering a few more options during the install....

[manono]

Tips?

As mentioned, don't use Nero to encode.
As implied by mikiem, find out the original framerate. If every other frame is a dupe, then it's really 29.97fps. If 3 out of every 5 frames are dupes, then it's 23.976fps. Use AviSynth for frameserving and remove those duplicate frames using Decomb's Decimate (Decimate(2).Decimate(5) if 23.976fps). Your bitrate efficiency will skyrocket after removing the dupes.
As mentioned, use AviSynth to resize.
Use AviSynth to do any colorspace conversions necessary.