rendering time

[Fred Foronda]

Originally Posted by John Rofrano

When I capture with Connect HD, I capture direct to a CineForm AVI and there isn’t even an m2t file on my hard drive. (no need for ‘em)

~jr

Does this applies to the supplied Cineform codec on vegas 6c. I am still debating weather or not to get the full blown Connect HD. Again thanks for everyone's contributions!!

[Fred Foronda]

Originally Posted by John Rofrano

No, there is no loss in quality if you are using the CineForm codec. The intermediary is not a proxy. It’s a high-quality render-ready copy of the original m2t file. You can read about the quality on CineForm’s web site here.



When I capture with Connect HD, I capture direct to a CineForm AVI and there isn’t even an m2t file on my hard drive. (no need for ‘em)

~jr

Does this also applies to the supplied cineform codec that comes with veags 6c? I am still debating if I still need the full blown Connect HD.

Thanks everyone!

[Jon Omiatek]

Originally Posted by John Rofrano

You might want to rethink your strategy and get the best hardware for the job. Today, that would be AMD X2.

~jr

After a bunch of research, you are correct the AMD X2 definately outpreforms intels p4 dual core 3.2ghz. I priced the motherboard and processor and it comes to about $800. I can use the rest from my other system, meaning graphics, hard drives ane memory. I might just do it :)
Thanks for the heads up!

[John Rofrano]

Originally Posted by Fred Foronda

Does this also applies to the supplied cineform codec that comes with veags 6c?

Yes, you can render your M2T using the CineForm codec in Vegas 6 and render right from that codec to your final format (i.e,. back to tape or to DVD). The whole idea behind GearShift is to take advantage of this fact and automate the process for you if you have a lot of M2T files to process.

~jr

[John Rofrano]

Originally Posted by Jon East

After a bunch of research, you are correct the AMD X2 definately outpreforms intels p4 dual core 3.2ghz. I priced the motherboard and processor and it comes to about $800.

Sad but true, I know. I have the specs for my system on the PC Equipment page of my web site. The ASUS A8N-SLI Premium ($167) and AMD X2 4600+ ($547) are $714 at newegg.com. They have been solid as a rock for me. If you got the top-of-the-line AMD X2 4800+ ($630) it would be $797. Something to consider.

~jr

[Yi Fong Yu]

and for those interested in building new amd dualcore systems, there are socket 939-based Opterons that can OC'd to kingdom come (4800+ levels) for a price closer to x2, 3800+. FYI.

re: amd. they were kicking ass waaay back in the late 90s when the 'k7' architecture came out and performed faster clock for clock besting equivalent p3's. k6 was horrible, but k7 was when amd became a serious contender/alternative to a lazy intel. ah those were the days =).

[David Newman]

Originally Posted by Fred Foronda

Does this also applies to the supplied cineform codec that comes with veags 6c? I am still debating if I still need the full blown Connect HD.

Thanks everyone!

Connect HD has it advantages, first is encoding performance. Connect HD will convert M2T to CFHD 3+ times faster than Vegas/Gearshift. Then there is the quality controls, and the huge range of capture features supported. All of this info is available from www.cineform.com. The free trial will help you decide.

[Robert M Wright]

From what's been said here, it sounds like CineForm's codec might possibly get confused for a lossless codec. It isn't.

As a practical matter, rendering final output, from a CineForm copy of the source M2T original, will work just fine for almost anything, but if you want the absolute best possible quality render, the original MT2 source is the only choice between the two (simply because it is the original, unaltered version). It is unlikely anyone will visually perceive a difference though.

I only mention this, because not making the seemingly subtle distinction, between absolute and practical, can potentially come back to haunt someday (so to speak). Most humans would not be able to tell the difference between a 320kbps MP3 audio encoding and it's source either, but I doubt anyone in the audio profession would want to confuse the MP3 copy for a "perfect" copy.

For editing purposes, CineForm's codec is, for HD, much like using a DV codec for SD, in that it has most of the advantages of working with uncompressed data, yet with much smaller file sizes, with only extremely minimal loss in quality.

[John Rofrano]

This is a good distinction to make. I don’t believe anyone said the CineForm codec was lossless and I would not want to mislead someone into thinking it was. What I was trying to point out was that it is less lossy than M2T. So I don’t agree with your MP3 analogy. If I read it correctly, you are comparing CineForm to a 320kbps MP3 and M2T to an original Uncompressed wave file. M2T is no where near a “perfect” uncompressed copy. It is highly compressed. More so than CineForm.

CineForm uses variable wavelet compression at a rate of 5:1 to 10:1. An MPEG2 Transport Stream (M2T) uses compression of about 20:1! When you convert an M2T stream to CineForm you are going from 20:1 compression to only 10:1 compression (or even as low as 5:1 compression in some cases). You are going from a lower quality codec to a higher quality codec.

To more accurately state your MP3 example I would say that M2T is a 128kbps MP3 and CineForm is a 320kbps MP3. What you are doing then, is recording the original at 128kbps MP3 and encoding it as 320kbps MP3 later to work on it. You are right, you will probably not perceive any loss in quality when rendering a 128kbps MP3 (M2T) to a 320kbps MP3 (CineForm)

I do agree with you that all encoding suffers some loss. So even going from the lower quality M2T to the higher quality CineForm may lose something in the translation. Like I said, I don’t even capture M2T files half the time. I capture straight to CineForm.

~jr

[Yi Fong Yu]

stepping back a bit. are we really going to be stuck with .m2t as "the" sole source codec for HD-based content we want to record? are there future codecs from other competing HD taped based transports that yield better/high quality results than .m2t's?

[John Rofrano]

Originally Posted by Yi Fong Yu

stepping back a bit. are we really going to be stuck with .m2t as "the" sole source codec for HD-based content we want to record? are there future codecs from other competing HD taped based transports that yield better/high quality results than .m2t's?

There already are but not from tape based transports. The Panasonic HVX200 does not use M2T (which means it doesn’t record HDV since M2T is the HDV standard). In fact, it doesn’t even record HD to tape. It only records it to P2 memory cards. They call their version DVCPRO-HD and it records with less compression but less compression means a higher data rate (up to 100Mbps), so it can only record to solid state memory cards or hard drives.

BTW, we are not “stuck”. HDV M2T is very high quality. The “quality” of my HDV footage far surpasses ANYTHING I’ve shot on SD. I apologize if this thread is giving you the impression that HDV M2T is low quality. It is not. It’s just that CineForm is higher which is why it is recommended that it is safe to convert to CineForm and render from there. You should not read anything else into it.

Perhaps my analogy of M2T equating to 128kbps MP3 is what gave you that impression. I picked that rate because that is said to be CD quality which most people feel is high quality. Perhaps it was a bad analogy.

~jr

[Fred Foronda]

Too much technical stuffs here. So heres what I did and would like to share. I did it as simple as can be. Downloaded the triall version of CF and did a 15 sec clip. Edit clip just by doing simple crossfade transitions. Then printed back to HDV tape. Not bad, I must say the quailty on my HD TV I can even tell, there was no difference from the original footage. But the ratio I got is another story 1:8 ratio when rendering. I need a faster computer!!! Atleast Cineform HD converted the m2t file on the fly and it has scene detection!!! I am definelty picking one up after the trial period is over.

[Fred Foronda]

Too much technical stuffs here. So heres what I did and would like to share. I did it as simple as can be. Downloaded the trail version of CF and did a 15 sec clip. Edit clip just by doing simple crossfade transitions. Then printed back to HDV tape. Not bad, I must say the quailty on my HD TV I can't even tell, there was no difference from the original footage. But the ratio I got is another story 1:8 ratio when rendering. I need a faster computer!!! Cineform HD converted the m2t file on the fly and it has scene detection!!! I am definelty picking one up after the trial period is over.

[Mark Bryant]

So in summary:

- re-encoding will always carry some loss, even if is to a less compressed format.
- But that in practical terms, one is unlikely to notice this loss when using Cineform as an intermediate render.

But what I’m still not sure about is… it’s not just re-encoding we are dealing with, it is also editing.

So, comparing the 2 end-to-end scenarios. And let’s assume the output format is m2t, printed back to tape:

1. Edit the M2t (either natively with fast PC, or using a proxy). Single render from m2t back out to new m2t.
2. m2t to Cineform (assume I do this in Vegas). Edit Cineform, render back to m2t for output to tape.

I’ve read that there are concerns with having Vegas edit m2t directly, specifically with color correction. So it is possible (or correct) that flow 2 could actually be better?


Mark

[Yi Fong Yu]

hi john,

i realize m2t's are nice. having just done a wedding shot on XL H1 =).

i just wanted to know if there are alternative tape transport-based codecs that make low-end machines easier, taht's all =).