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View Full Version : Lossy vs Lossless video sourcing on DVD


flipsaari
2007-05-31, 11:14 PM
Ok so Im making this DVD of a show and I have multiple angles of video sources.

As I was reading the rules on TTD of encoding video files to author on DVD i was freaked out when I saw that video from "VCD/DIVX/MOV/ASF/ etc werent allowed.

So I started asking some folks who know more than I do, and one person told me that a digital videos are lossy by nature but if I have the raw files then thats as close as I can get. And this is true in my scenario all my files are straight from the folks' cameras, so in that case I am allowed to use the avis, .movs and motionjpegs (mpg but thats what its classified as in Gspot)??.

Heres a link of the sources that im 'unsure' about: http://img252.imageshack.us/my.php?image=videospecsnp3.jpg

Another thing is that im editing all of the footage in Adobe Premier Pro 2. So my final lineage would go: raw footage (for each one) > TMPEG ENC > DV AVI > Adobe Premier > Out to the DVD format (I beleive MPEG-2/VOB) and authored finally.

But is that too many conversions? Is that a no no? I really hope not because Im almost done my work in Adobe (and I may even consider taking to to DVD lab bro to add interactive angle selection capabilities, so that would add another point in the lineage)

Phew! Ok so thats my project and hte bottom line I guess im wondering here is, how do I know what I can use with respect to raw footage formats and specifications, encoding and authoring.

saltman
2007-06-02, 03:53 PM
I'll look into this when I have a little more time. I am about to go to a wedding. Two on right are out. They are mpeg1 and can't be shared. one on bottom left is out. One on top left has a strange formatting size.

Why not capture the DVs with premiere? It doesn't look like you are rendering twice in the path you stated but I didn't look too close.

You should only be using raw DV avi. anything else would be cascade rendering which will introduce artifacts and degrade the quality.

Silver Stallion DVDs
2007-06-02, 04:21 PM
You should only be using raw DV avi. anything else would be cascade rendering which will introduce artifacts and degrade the quality.
I've dropped mpeg4 clips into Vegas projects that covered spots where no DV avi footage existed and you'd be hardpressed to tell that the footage was sourced from a lossy format. I don't recommend using sources like this if a DV avi source exists, but a lossy source (if it's the only one available) is better than nothing.

Whenever I included this footage, I used a special rendering process. I learned it from watching the Vegas Video series of DVDs made by Edward Spotted Eagle. I can't remember what it's called at the moment, but basically, it goes over the clip several times in the rendering process and the output is much better than what you would get with a standard VBR encoding. I don't have time to dig for the effect to which I'm referring, but I'll look into more later.

Randy

saltman
2007-06-02, 10:27 PM
It is acceptable for small portions of video to be filled in with lossy material (if it's the only source) as a general rule. I think you will be unhappy if you mix an entire multi-angle show with lossless and lossy media. I know I have tried in the past and it was incredibly obvious to me. And the lossy source came from pro cameras to begin with.

I can see a big difference in mepg4 that has been re-rendered to mpeg2. The livephish series for instance is put out in mpeg4 and many people have put it onto dvd. It is very blocky and sub standard. even before being rendered back to mpeg2. I have also made DVDs from my buds early HDD cam that recorded to mpeg4 and it looks crappy IMO.

I would appreciate you digging up what you could about the rendering technique you describe.

flipsaari
2007-06-03, 03:42 AM
Two on right are out. They are mpeg1 and can't be shared. one on bottom left is out. One on top left has a strange formatting size.

:wtf: The one on the bottom right is my main source, it runs nearly the entie concert, so are you sure that must be omitted? Because theres that main source and two others that I use as primarys (Im certain those two are usable as they have been sourced for DVDs in the past) but what I posted were 4 ones that I was unsure about, excepet I didnt expect the bottom right one to be omitted. And the one above it has great quality. Although the two on the LEFT are ones that are motion jpeg and they are more grainy (though it gives you a cool visual effect) their usefulness is minimal compared to the others.

Silver Stallion DVDs
2007-06-03, 10:42 PM
I would appreciate you digging up what you could about the rendering technique you describe.
It's called supersampling. Rather than try to explain what it is, just do a google and read about it.

How to use it: basically, the very bottom track in the timeline (that you probably never use or even pay attention to unless you're using supersampling) is the Master Video Bus Track.

Just as if you were going to insert a volume envelope (right click on the volume track, and click "insert/remove envelope" > "volume"), you do the same thing on the Master Video Bus Track. Except you follow this sequence: "insert/remove envelope > video supersampling."

You raise the envelope at increments of 1 up to the highest which is 8. However, the higher you set it, the longer it takes to render (and it can really increase render times). Whenever you are using the inferior video, you raise the slider, and for any segments of straight DV, you just lower it to zero.

I used it in the 2005 U2 Minneapolis 2-DVD set that I authored (and it was recently torrented), and I was very pleased with the results. There were segments of video missing, and the only thing I had to plug them with was mpeg4 shot with a micro-cam. I also used some mpeg4 segments as overlay video when creating a composite.

Also, if you use it as picture-in-picture footage, it's much smaller and not likely to cause any problems - so that's another possibility if you have some decent mpeg4 clips.

Randy

saltman
2007-06-04, 05:47 PM
:wtf: The one on the bottom right is my main source, it runs nearly the entie concert, so are you sure that must be omitted? Because theres that main source and two others that I use as primarys (Im certain those two are usable as they have been sourced for DVDs in the past) but what I posted were 4 ones that I was unsure about, excepet I didnt expect the bottom right one to be omitted. And the one above it has great quality. Although the two on the LEFT are ones that are motion jpeg and they are more grainy (though it gives you a cool visual effect) their usefulness is minimal compared to the others.looked a little closer today.

all four are outside of our acceptable material. if it's something you're into. please go for it. we just can't allow it to be shared here or we would be opening the doors to VCD to DVD, etc.



Randy - thanks for the info. re: supersampling. learn something new everyday.

flipsaari
2007-06-04, 11:46 PM
OK thanks.