HDV source to SD and WMV-HD with Vegas 6

tharris wrote on 5/23/2005, 6:19 AM

According to the Vegas 6 documentation, you capture HDV which results in an MPEG-2 transport stream and when you want to edit, you create an intermediate .AVI file.

I have a client that wants a DVD in SD format but also wants to play a real HD file on their computer and for that, it looks like WMV-HD would work.

The question I have is what would be the format of the intermediate .AVI file? The help file says to use the Sony NTSC DV Widescreen (NTSC DV Windescreen 24p 2-3-3-2 pulldown .avi template) if the destination is 24p DVD (is this the same as a regular SD DVD?). If the destination is WMV-HD, use one of the HDV 720 or 1080 intermediate templates.

So, do you have to create 2 different types of intermediate .avi files depending on what the destination is going to be or can you create one type of intermediate .avi file, edit it, then replace the intermediate file with the HDV source after editing? If you can get by with one type of .avi file, which one is the "best" for this kind of output?

Any insight would be appreciate for a good workflow....

Thanks

Comments

bruceo wrote on 5/23/2005, 6:57 AM

Just one. This is the exact workflow that I use. I create DV wide proxies and then output to DVD with these and then when I need WMVHD output I replace the proxy source with the m2t source by changing the folder name that the proxy files are in and then when vegas comes up I replace the proxy file with the corresponding m2t.

The only irritation I have is occasionally, usually about 1 in every 5 proxy renders, the proxy will not be frame and/or audio synch accurate. I haven't figured out why this happens, but is usually remedied by rerendering that particular proxy.

The only downfall to this workflow is that it takes a freakin eternity. To do a 4 tape 4 hour job easily takes 10-14 hours on a P4 3.2 to get to the point that you can start editing

tharris wrote on 5/23/2005, 7:09 AM

Thanks bruceo - one question - can you explain the proxies that you are using; I am not clear on that (how to create and use). I didn't see anything in the Vegas documentation about proxy files.

Thanks

Wolfgang S. wrote on 5/23/2005, 10:23 AM

A better way is to use the tool Gearshift. It allows you to generate different proxys - can be CineForm intermediates, can be DV-avi widescreen, but can also be mjpeg-avi proxys (the mjpeg-avi proxys are still my favorites, since here you avoid any pixel ratio driven issues).

Coursedesign wrote on 5/23/2005, 10:48 AM

Yes, and by avoiding an intermediate DV codec you don't go from 4:2:0 to 4:1:1 to 4:2:0 color sampling (in NTSC land), and you avoid additional DV25 artifacts.

Spot|DSE wrote on 5/23/2005, 10:53 AM

Actually, if you're using GearShift, it doesn't matter what the intermediary is, because the intermediary is never used for the final render. It's just a proxy file used in the editing stages, and then replaced with the YUV or Cineform, or m2t files for final render.

mark-woollard wrote on 5/23/2005, 11:03 AM

Roughly how much faster would the final render be coming from a CineForm Intermediate versus m2t?

Thanks

tharris wrote on 5/23/2005, 12:31 PM

Thanks for the great tip. I took a look at Gearshift and it looks like this would be a good tool.

What proxy file type would work the best if you want to create both an SD type DVD video and an HD WMV file from the same edited source?

How long does it typically take for Gearshift to create the proxy file if the HD source is 1 hour long?

Wolfgang S. wrote on 5/24/2005, 12:44 AM

Typically, people tend to use DV-avi widescreen as proxy. This has the advantage, that you work with proxys with great realtime-features - since it is DV material. The disadvantage with this proxys is, that the material must be resized a little bit - since 1080i and 16:9 widescreen cannot matched exactly. Means, that things like PiP or pan/crop are not adusted with 100% precision - and should be checked after switching back to m2t material.

Another possiblity would be, to use the Cineform code, or the Sony YUV codec. I am not so convinced to use the Sony YUV codec, since files become huge. Also, the Cineform codec generates huge files, that are not played back with full 25 fps (PAL). For the Cineform codec, a switch back is not foreseen - but you can do it with a trick: you generate your own template, with "HD " in the template name - and then you can gear out the material. See an example for the template here:
http://videotreffpunkt.com/tutorials/HD%20Gearshift/HD%20Gear-34.gif

File size: if the m2t material are 100%, according to my measurement DV.proxys are something about 116%, Cineform proxys are something about 400%.

That is the reason why I tend to use other proxys - mjpeg-avi material, that you can use if you have an mjpeg-avi codec in your system. For example, Pegasus (PIC) or Morgan delivers such codecs. The advantages of such codecs are:
- you can size them exactly as you want - for example, I work with proxys of 960x540.
- the file size is small - something about 40% of the m2t material, even if that depend on the settings you use
- color seems to be fine, since the PIC works in 4:2:2
- render time is relativ quick - a little bit more of the runtime of the video, if you render to "draft" for the proxy (what is still good enough for a proxy) - found on a 3.2 Ghz P4.

A tutorial for that has been developed here:
http://videotreffpunkt.com/thread.php?threadid=1141&boardid=36&styleid=6

Unfortunately, it is in German - but the pictures should deliver at least some additional support.

Kr
Wolfgang