.m2t format from SonyFX1000 back to .m2t losslessly? at DVinfo.net

Martin Bannet · January 28th, 2010, 08:11 PM

Hi there.

Enjoying my new camcorder when the weather and my health (which is never dependable) allows me to 'get out there' and shoot.

VEGAS pulls in the video from my Sony FX1000 as .m2t files. (Do I have a higher definition option by the way using Vegas re capturing footage from the camera?)

Now if I want to rerender some edited video losslessly down to a file I can further work with later, do I rerender back to .m2t format or something else?

What are the optimum project settings for lossless rendering in Vegas (using default .m2t files)? Anyone have a preset for me to use - maybe?

Hope I'm not asking too much. Just want to provide the best/cleanest video for viewing and editing (at a later time) possible....

Your suggestions are GREATLY welcome, as always!

Martin Bannet

Seth Bloombaum · January 29th, 2010, 11:47 AM

"Best" and "cleanest" are difficult terms to deal with. There are always "better" and "cleaner" approaches out there, usually, we're trying to determine "how good is good enough for (my project, client, standards, etc.)".

First, M2T is far from lossless. It's a very lossy codec. If I remember, about 22:1 compression over uncompressed. Don't let this depress you, though, it's a great shooting format that was created for very good reasons.

As (arguably) good it is as a shooting format, it's merely an OK editing format, because,
a) it needs to be uncompressed on the fly for editing, with a significant processor load, smart software helps!
b) its color resolution isn't that great, doesn't look that good if you do a few generations of rendering, due to the compression scheme.
c) its a GOP, or, group of pictures codec. Meaning (briefly) that if you have the cursor parked on a frame, that frame doesn't exist by itself, it's been created in reference to 15 frames.

The important part for you is that:
1) Original camera tapes are a good archive.
2) Your original captures on hard drive are a good archive.
3) Vegas Pro 8 and on can do a "smart render" of M2T, meaning that if the clip on the timeline is entirely unchanged, you can render a portion with no generation loss. In this, V just directly copies the portion of the original file you're interested in.
4) There are other codecs for use in various scenarios, such as Lagarith, Cineform, ProRes422, DNxHD - lots of references to these in this forum.

Lots of info here - is this starting to answer your question?

John Cline · January 29th, 2010, 11:13 PM

Vegas will losslessly "Smart-Render" .M2T files. If you do nothing more than edit your video using only cuts and save it as MPEG2 using the appropriate HDV template, then the resulting edited video will be identical in quality to the original footage.

Shawn Legg · January 29th, 2010, 11:31 PM

That is awesome to know, but what about dissolves or a light colour correction? Is there any way to render that withou losing anymore quality than the already 22:1 as stated above. I noticed when I took my file from vegas into after effects to colour correct, when I brought it back into vegas it looked a little weird

YouTube - MyBowlingVideo

I am not sure what to render an M2T file from after effects as. Currently as AVI, I don't think there was an M2T option.

It is on youtube so it is already losing a bit but compared to this one with no correction

YouTube - SONY HVR-HD1000U Camera Test

I can see a difference

both of these are my footage so I know the rendering was the same.

Sorry for the hijacking of the thread but I think this relates.

Prech Marton · January 30th, 2010, 04:29 AM

"First, M2T is far from lossless"

Did he say that?

John Cline · January 30th, 2010, 05:38 AM

There is a not insignificant amount of loss when the HDV camcorder compresses the video from the camera section into 25Mbps MPEG2 video and records it to HDV tape. There is no further loss when the video is captured from the camcorder via Firewire to your computer as it is just a bit-for-bit file copy between the tape and the hard drive. Like I said earlier, you can use Vegas to do a cuts-only edit and the "render" will be lossless, it is just another bit-for-bit file copy except you have cut out some parts.

Now, if you modify the video in any way by adding titles or color correcting or adding any other effect, then the video will need to be recompressed and this will NOT be lossless, although if you do it right, you will only have to recompress the video once. You can convert the M2T file into an intermediate AVI file using the Cineform, Lagarith, HuffYUV codecs or completely uncompressed. The filesize of these files will be considerably larger than the original M2T file, but you can freely move the file between programs and dmodify it in whatever way you want and then recompress it into your final destination format which might be MPEG2 or h.264/AVC or something else.

Martin Bannet · January 30th, 2010, 10:09 AM

Thank you so much everyone! Am .pdf'ing this whole thread and will experiment with everything suggested!

Very cool - all of you to respond!

God bless!

Martin Bannet

Brian Luce · January 30th, 2010, 08:06 PM

You should be able to render to m2t just fine. Look for "Main Concept MPEG 2".

Btw, Here are two screen grabs...
One is m2t with no fx -- clean, the other has some graphics, a keyed in bg and a chroma filter.

Steve Renouf · January 31st, 2010, 03:41 AM

Quote:

Originally Posted by Brian Luce

You should be able to render to m2t just fine. Look for "Main Concept MPEG 2".

Btw, Here are two screen grabs...
One is m2t with no fx -- clean, the other has some graphics, a keyed in bg and a chroma filter.

Yes, you can quite clearly see the re-compression artifacts.

January 28th, 2010, 08:11 PM	#1
Martin Bannet Regular Crew Join Date: Dec 2008 Location: Natchez, MS Posts: 26	.m2t format from SonyFX1000 back to .m2t losslessly? Hi there. Enjoying my new camcorder when the weather and my health (which is never dependable) allows me to 'get out there' and shoot. VEGAS pulls in the video from my Sony FX1000 as .m2t files. (Do I have a higher definition option by the way using Vegas re capturing footage from the camera?) Now if I want to rerender some edited video losslessly down to a file I can further work with later, do I rerender back to .m2t format or something else? What are the optimum project settings for lossless rendering in Vegas (using default .m2t files)? Anyone have a preset for me to use - maybe? Hope I'm not asking too much. Just want to provide the best/cleanest video for viewing and editing (at a later time) possible.... Your suggestions are GREATLY welcome, as always! Martin Bannet

January 29th, 2010, 11:47 AM	#2
Seth Bloombaum Inner Circle Join Date: Sep 2003 Location: Portland, Oregon Posts: 3,420	"Best" and "cleanest" are difficult terms to deal with. There are always "better" and "cleaner" approaches out there, usually, we're trying to determine "how good is good enough for (my project, client, standards, etc.)". First, M2T is far from lossless. It's a very lossy codec. If I remember, about 22:1 compression over uncompressed. Don't let this depress you, though, it's a great shooting format that was created for very good reasons. As (arguably) good it is as a shooting format, it's merely an OK editing format, because, a) it needs to be uncompressed on the fly for editing, with a significant processor load, smart software helps! b) its color resolution isn't that great, doesn't look that good if you do a few generations of rendering, due to the compression scheme. c) its a GOP, or, group of pictures codec. Meaning (briefly) that if you have the cursor parked on a frame, that frame doesn't exist by itself, it's been created in reference to 15 frames. The important part for you is that: 1) Original camera tapes are a good archive. 2) Your original captures on hard drive are a good archive. 3) Vegas Pro 8 and on can do a "smart render" of M2T, meaning that if the clip on the timeline is entirely unchanged, you can render a portion with no generation loss. In this, V just directly copies the portion of the original file you're interested in. 4) There are other codecs for use in various scenarios, such as Lagarith, Cineform, ProRes422, DNxHD - lots of references to these in this forum. Lots of info here - is this starting to answer your question? __________________ 30 years of pro media production. Vegas user since 1.0. Webcaster since 1997. Freelancer since 2000. College instructor since 2001.

January 30th, 2010, 04:29 AM	#5
Prech Marton Major Player Join Date: May 2004 Location: hungary Posts: 462	"First, M2T is far from lossless" Did he say that? __________________ Relaxing clips with waterfalls and music, 3D photos, 3D videos: www.3d-video.hu

January 30th, 2010, 10:09 AM	#7
Martin Bannet Regular Crew Join Date: Dec 2008 Location: Natchez, MS Posts: 26	You folks are awesome sources of information! Thank you so much everyone! Am .pdf'ing this whole thread and will experiment with everything suggested! Very cool - all of you to respond! God bless! Martin Bannet

January 30th, 2010, 08:06 PM	#8
Brian Luce Inner Circle Join Date: Jan 2006 Posts: 2,290	You should be able to render to m2t just fine. Look for "Main Concept MPEG 2". Btw, Here are two screen grabs... One is m2t with no fx -- clean, the other has some graphics, a keyed in bg and a chroma filter. Attached Thumbnails

January 29th, 2010, 11:13 PM	#3
John Cline Major Player Join Date: Oct 2002 Location: Albuquerque, New Mexico USA Posts: 333	Vegas will losslessly "Smart-Render" .M2T files. If you do nothing more than edit your video using only cuts and save it as MPEG2 using the appropriate HDV template, then the resulting edited video will be identical in quality to the original footage.

January 29th, 2010, 11:31 PM	#4
Shawn Legg Regular Crew Join Date: Sep 2009 Location: Hamilton, ONTARIO Posts: 29	That is awesome to know, but what about dissolves or a light colour correction? Is there any way to render that withou losing anymore quality than the already 22:1 as stated above. I noticed when I took my file from vegas into after effects to colour correct, when I brought it back into vegas it looked a little weird YouTube - MyBowlingVideo I am not sure what to render an M2T file from after effects as. Currently as AVI, I don't think there was an M2T option. It is on youtube so it is already losing a bit but compared to this one with no correction YouTube - SONY HVR-HD1000U Camera Test I can see a difference both of these are my footage so I know the rendering was the same. Sorry for the hijacking of the thread but I think this relates.

January 30th, 2010, 05:38 AM	#6
John Cline Major Player Join Date: Oct 2002 Location: Albuquerque, New Mexico USA Posts: 333	There is a not insignificant amount of loss when the HDV camcorder compresses the video from the camera section into 25Mbps MPEG2 video and records it to HDV tape. There is no further loss when the video is captured from the camcorder via Firewire to your computer as it is just a bit-for-bit file copy between the tape and the hard drive. Like I said earlier, you can use Vegas to do a cuts-only edit and the "render" will be lossless, it is just another bit-for-bit file copy except you have cut out some parts. Now, if you modify the video in any way by adding titles or color correcting or adding any other effect, then the video will need to be recompressed and this will NOT be lossless, although if you do it right, you will only have to recompress the video once. You can convert the M2T file into an intermediate AVI file using the Cineform, Lagarith, HuffYUV codecs or completely uncompressed. The filesize of these files will be considerably larger than the original M2T file, but you can freely move the file between programs and dmodify it in whatever way you want and then recompress it into your final destination format which might be MPEG2 or h.264/AVC or something else.