industry-level downscaling to SD - how do they do it?

[Perrone Ford]

Originally Posted by Tony Davies-Patrick

I don't think that economic recession is the main cause, but more to do with the massive rise in streaming videos via internet. There is no doubt in my mind that the future of TV and films is the World-Wide-Web.

I'll buy that, but we aren't there yet. The US has some of the best broadband connectivity in the world, and honestly, less than a third of our population can stream movies. It's going to take some time before the WWW replaces a set top box. Heck I *MAKE* movies and I still prefer BluRay and DVD. The quality from streaming is 3-4 Mbps at BEST. Youtube quality may look ok for some, but on a large display in the living room, I really want something better.

[Stelios Christofides]

Originally Posted by Tony Davies-Patrick

...Regarding producing actual DVDs, I never try to squeeze 2-hours of movie onto a DVD disc, and ALWAYS try to stick to the 1-hour max rule, because this allows you to include both sound and video at highest SD levels throughout the DVD. With 2-hour movies I always prefer to make them into 2-disc DVD sets with 1-hour on each disc. On the subject of bit rates, as mentioned, I normally compress at 9000-9,400 for a 60-minute SD movie (inclusive of authoring buttons & images) and not above that level...

Tony why don't you use a double layer DVD so you can have one copy for your customers? That's what I do and the quality is great, besides double layer DVDs are not that expensive.

Stelios

[Tony Davies-Patrick]

Stelios, the reason is marketing and sales. The cost of producing a double-layer with onbodies in DVD packs and seal-wrapped is similar to that package as a 2 disc DVD set. The advantage is that I can advertise the movie as a special 2-disc pack as opposed to a single disc, and this attracts higher sales.

[Jacques E. Bouchard]

Thanks to everyone for shedding light on this matter. Are there standalone MPEG-2 compressors that would let me do the second pass (H.264-MPEG-2) rather than open a new project in Vegas? Also, are there ways to tailor how certain scenes are rendered in Vegas or Premiere? Sometimes it's only a matter of a few seconds that get pixelated, and I'd like to target that area only.

J.

[Bruce Watson]

Originally Posted by Perrone Ford

...The US has some of the best broadband connectivity in the world, and honestly, less than a third of our population can stream movies...

Well, it sorta depends on how you define "best" I think. There are a number of organizations that track broadband implementation and usage around the world. The US ranking tends to average around 15-20, and is falling steadily. Here's a specific report to look at, see page 22. There are other reports, this is just the one that came to hand the quickest for me.

The problem isn't so much broadband penetration in the US, it's more about speed. The bit-rates just aren't there, even in the major cities, to support downloading full blu-ray (1080p24) quality video.

Without either competition in the last mile (to your house), or a government mandate, there's really no reason for the telecom / cable providers to improve the infrastructure. They know from experience that we'll continue to pay high rates for low grade service rather than give up the service all together. So what's their incentive to move from 1960s copper wire (which they already have installed) to fiber optics (which would be expensive and painful to install, and would generate hardly any additional revenue)?

Yet even with the problems of obsolete infrastructure in the US, Netflix downloads now account for 20% of peak 'net activity. Amazing -- people really prioritize convenience over quality.

Much as I would like to see it, I doubt I'll have fiber optics to my house in my lifetime. Thank goodness for Netflix, blu-ray, and roof-top antennas!

[Tony Davies-Patrick]

Originally Posted by Jacques E. Bouchard

...Sometimes it's only a matter of a few seconds that get pixelated, and I'd like to target that area only.

J.

Jacques, I find that sometimes, rather than converting directly from full 1080 to mpeg-2, I convert the problem file to a HDV 720P file prior to compressing back to mpeg-2 and this often prevents certain difficult clips from pixelating, especially if the problem area is large areas of black in the scene that need bringing back to solid black. If this doesn't work, then try lowering the Gamma levels on that particular clip during post editing. Sliding the Gamma level from zero to minus until you have pure clean blacks, also works very well in lowering noise levels in night footage.

[Jacques E. Bouchard]

Originally Posted by Bruce Watson

Yet even with the problems of obsolete infrastructure in the US, Netflix downloads now account for 20% of peak 'net activity. Amazing -- people really prioritize convenience over quality.

Who can forget "CD quality" 128-kbps mp3s? ;-)


J.

[Jacques E. Bouchard]

Originally Posted by Tony Davies-Patrick

Jacques, I find that sometimes, rather than converting directly from full 1080 to mpeg-2, I convert the problem file to a HDV 720P file prior to compressing back to mpeg-2 and this often prevents certain difficult clips from pixelating, especially if the problem area is large areas of black in the scene that need bringing back to solid black. If this doesn't work, then try lowering the Gamma levels on that particular clip during post editing. Sliding the Gamma level from zero to minus until you have pure clean blacks, also works very well in lowering noise levels in night footage.

Thanks Tony. I also see the problem during transitions between clips, not just with noisy blacks. I'll also try Robert's suggestion to render to H.264 first, then to MPEG-2.


J.

[Garrett Low]

Hi Jacques,

If you are trying to use Vegas to go one step from HD to an MPEG-2 for DVD you will never achieve the quality you're looking for. The problem lies in two areas, the fist is, much like FCP, Vegas does not scale video very well. As Perrone mentioned the best quality you'll get is taking the HD edit to a lossless HD file, then use an external program to scale it. VDub does a good job and is free.

The second is that the MPEG encoder in Vegas is decent but there are much better ones if you are willing to pay for them. One of the best encoders that won't cost you an arm and a leg is Cinema Craft Encoder SP3. It can do up to 8 passes so it will compress your video pretty much as far as it can go and produces noticeably better results than most other encoders small operations can afford. I has an adaptive quantization matrix or I believe you can adjust the quantization matrix based on segments of the movie so you can adjust it to yield the best quality for each given scene. But, it is $1000 for a program that basically just encodes DVD's. So if it can pay for itself it could be worth it but it is still expensive for most small companies.

I'm not sure about encoding first to H.264 then to MPEG. Remember that H.264 is a very compressed format already. I've tried this route and there is still noticeable recompression issues. It might be the encoders that come with Vegas but I did notice a loss in quality. H.264 was never meant to be an intermediate codec. I would use one of the other lossless intermediate codecs instead.

It does take longer to do the multi-step process of HD render, resize, render to mpeg but it does yield noticeably better results.

Just my experiences and take on things.

-Garrett

[Ali Jafri]

Wow, lots of resources and information in this thread!

Can anyone discuss the comparisons in quality and performance of video encoders like Adobe Media Encoder CS5 and ProCoder 3 etc, as compared to TMPGEnc for scaling HD down to SD for DVD.

Also, would the same HD to SD downconvert methods and techniques apply when converting HD source to DV PAL for broadcast?