Reducing loss of video quality

Terry McGregor · June 21st, 2007, 08:23 PM

When converting files from .m2t to .avi (Cineform), is it better to use HDLink (v3.02) convert or Sony Vegas (v7.0e) render? I don't care about the time taken, I just want to minimise the 1st generation loss of video quality.

On a similar note, can I use a Cineform tool to reduce my 2nd generation loss of video quality, or is Sony Vegas render my only option?

Here's what I'm doing
1. HDVSplit to importing my .m2t files
2. NEO HDV HDLink to convert .m2t to .avi (1st generation loss)
3. Sony Vegas to edit .avi files
4. Sony Vegas to render a big edited .avi file for archive (2nd generation loss)

Salah Baker · June 21st, 2007, 08:36 PM

why not use the HDlink to convert to Cineform from the start?

Terry McGregor · June 21st, 2007, 09:29 PM

I found the answer to my first question ... to minimise the 1st generation loss, I should use HDLink convert (with Quality = High or Film Scan) not Sony Vegas render. This is because Sony Vegas 7 only has access to Cineforms "Medium" quality setting, due to Sony's restricted license.

Can anyone tell me if I can reduce my 2nd generation loss of video quality? Or am I stuck with Sony Vegas render, which only has access to Cineforms "Medium" quality setting?

David Newman · June 21st, 2007, 09:48 PM

If you purchase NEO the Sony license is upgraded to support all the quality levels. Also if you use the Samrt rendering option in HDLink, unchanged segments will be completely lossless in Vegas.

Terry McGregor · June 22nd, 2007, 01:02 AM

Smart rendering sounds good. But what's a segment?

David Newman · June 22nd, 2007, 08:35 AM

A segment is a range of frames between edit events. Cut points mark segment boundaries, so transition etc.

Terry McGregor · June 27th, 2007, 12:22 AM

Can someone please confirm if the below solution is a better option for me. 1. HDVSplit to importing my .m2t files (one file per segment)
2. Sony Vegas and Vasst GearShift on the .mt2 files to create DV (or Cineform) proxies
3. Sony Vegas to edit the DV proxies
4. When ready to render, Vasst GearShift to exchange the DV proxies for the .m2t files
5. Sony Vegas to render project as MPEG-2 for Blu Ray (1st generation loss)
6. Sony Vegas to render project as a big edited Cineform .avi file for archive (1st generation loss)

This solution appears to allow me to get my edited HDV footage into Blu Ray, with just 1 generation of loss. Am I missing something?

It appears my original solution would only be better if:
- I was doing multiple (eg 10) generations of editing, as Cineform editing is near lossless, but .m2t editing isn't
- I was editing only a few (not all) segments, as Cineform Smart Rendering does not re-render the unedited segments, whereas native .m2t editing would.

Bill Ravens · June 27th, 2007, 06:22 AM

even if you use cineform, if you perform any edits(cuts, transitions, special FX, color adjustments, etc) within Vegas, the entire segment will be re-rendered, causing a generational loss. I do all my cuts within womble's smart renderere, then back into vegas.

Laurence Kingston · July 1st, 2007, 07:44 PM

Quote:

Originally Posted by Bill Ravens

even if you use cineform, if you perform any edits(cuts, transitions, special FX, color adjustments, etc) within Vegas, the entire segment will be re-rendered, causing a generational loss. I do all my cuts within womble's smart renderere, then back into vegas.

That doesn't quite make sense. Anything that is going to make Vegas rerender Cineform (transitions, color adjustment, etc.) is going to make Womble rerender the mpeg as well. On top of that, I'd take the tenth generation of Cineform over the second generation of mpeg (after a non-smartrender that is).

June 21st, 2007, 08:23 PM	#1
Terry McGregor New Boot Join Date: Jun 2007 Location: Sydney Australia Posts: 10	Reducing loss of video quality - 1st and 2nd generation When converting files from .m2t to .avi (Cineform), is it better to use HDLink (v3.02) convert or Sony Vegas (v7.0e) render? I don't care about the time taken, I just want to minimise the 1st generation loss of video quality. On a similar note, can I use a Cineform tool to reduce my 2nd generation loss of video quality, or is Sony Vegas render my only option? Here's what I'm doing 1. HDVSplit to importing my .m2t files 2. NEO HDV HDLink to convert .m2t to .avi (1st generation loss) 3. Sony Vegas to edit .avi files 4. Sony Vegas to render a big edited .avi file for archive (2nd generation loss)

June 21st, 2007, 09:48 PM	#4
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	If you purchase NEO the Sony license is upgraded to support all the quality levels. Also if you use the Samrt rendering option in HDLink, unchanged segments will be completely lossless in Vegas. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

June 22nd, 2007, 08:35 AM	#6
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	A segment is a range of frames between edit events. Cut points mark segment boundaries, so transition etc. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

June 21st, 2007, 08:36 PM	#2
Salah Baker Major Player Join Date: Jan 2007 Location: Patterson La. Posts: 207	why not use the HDlink to convert to Cineform from the start?

June 21st, 2007, 09:29 PM	#3
Terry McGregor New Boot Join Date: Jun 2007 Location: Sydney Australia Posts: 10	I found the answer to my first question ... to minimise the 1st generation loss, I should use HDLink convert (with Quality = High or Film Scan) not Sony Vegas render. This is because Sony Vegas 7 only has access to Cineforms "Medium" quality setting, due to Sony's restricted license. Can anyone tell me if I can reduce my 2nd generation loss of video quality? Or am I stuck with Sony Vegas render, which only has access to Cineforms "Medium" quality setting?

June 22nd, 2007, 01:02 AM	#5
Terry McGregor New Boot Join Date: Jun 2007 Location: Sydney Australia Posts: 10	Smart rendering sounds good. But what's a segment?

June 27th, 2007, 12:22 AM	#7
Terry McGregor New Boot Join Date: Jun 2007 Location: Sydney Australia Posts: 10	Can someone please confirm if the below solution is a better option for me. 1. HDVSplit to importing my .m2t files (one file per segment) 2. Sony Vegas and Vasst GearShift on the .mt2 files to create DV (or Cineform) proxies 3. Sony Vegas to edit the DV proxies 4. When ready to render, Vasst GearShift to exchange the DV proxies for the .m2t files 5. Sony Vegas to render project as MPEG-2 for Blu Ray (1st generation loss) 6. Sony Vegas to render project as a big edited Cineform .avi file for archive (1st generation loss) This solution appears to allow me to get my edited HDV footage into Blu Ray, with just 1 generation of loss. Am I missing something? It appears my original solution would only be better if: - I was doing multiple (eg 10) generations of editing, as Cineform editing is near lossless, but .m2t editing isn't - I was editing only a few (not all) segments, as Cineform Smart Rendering does not re-render the unedited segments, whereas native .m2t editing would.

June 27th, 2007, 06:22 AM	#8
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	even if you use cineform, if you perform any edits(cuts, transitions, special FX, color adjustments, etc) within Vegas, the entire segment will be re-rendered, causing a generational loss. I do all my cuts within womble's smart renderere, then back into vegas.