I've got a serious video quality issue with the Cineform codec and Vegas that I hope there's a solution for. When I compare the M2T file directly to the Cineform file after conversion, side by side, the converted M2T file looks spoltchy, like the number of colors has been reduced. Especially prevalant on walls and solid colored backgrounds. Further, this is noticeable on export to any format, including MPEG-2, WM9, etc. Any way to fix this? Am I doing something wrong?

Yes I think you must be doing something wrong as no one has reported this before. Are you using Connect HD 1.9, if not please try that first (download the trial from www.cineform.com.) If you still see he problem contact tech support by filing a trouble ticket a www.cineform.com/support.

Here's an example of what I'm talking about

http://www.mooreusa.net/example2.jpg

Check out the splotches on the left wall. This does not appear in the M2T file. The M2T file has a nice clean looking wall.

Any ideas?

I suspect it has something to do with the YUV / RGB conversion but I thought this had been dealt with. I am also using the newest version of Connect HD.

I would like to see the M2T file (can you upload a few GOPs with this frame -- you can use any file split tool if the original is too large.) Also are you using HDLink to do the conversion? Vegas will add a YUV to RGB conversion that HDLink will not. As you are using 720p, make sure the compression is set to progressive (not interlaced) and you might as well be using high quality.

Ok I will do some work and get you those files. I appreciate the help.

I have been using Vegas for the conversion. Now, I can use HDlink for the conversion from M2T to CF AVI, but eventually I'm going to have to be using Vegas to pull out clips. I also recall, but can't confirm right now, that the results were still similar regardless of what I used to convert, but I will check.

Ok, David, you are right - the video is MUCH MUCH better when converted from M2T to AVI using the HDLink tool than when using Vegas.

But here's the problem. At some point I HAVE to use Vegas for the intermediate editing. And I'm going to have to do so using the Cineform codec. Is it just not possible to use Vegas to export cineform files of an acceptable quality level? Will Adobe Premier Pro 1.5 be any better? I have to do _something_.

Peter,

Once the data is in CineForm Intermediate you shouldn't have the problem, even when rendering back out. If there is an issue with exporting to CFHD from Vegas I will look into that. We use a different MPEG decoder within HDLink than Vegas, so maybe that was the difference. I would still like to see that M2T so I can be more detailed in my response.

Connect HD's HDlink is higher quality and significantly faster than Vegas alone, so I don't any good reason not to use it. Could you please explain the steps you are taking in your editing workflow?

Premiere Pro running Aspect HD does have the edge as CineForm developed far more of the components involved, and a lot more YUV processing. Quality is higher as the DirectShow encoder under Aspect HD has more options then the Video for Windows codec used by Vegas. Plus I'm active user of Premiere with Aspect HD, if that counts for anything.

Yeah, what I usually do is render clips of no more than 5-10 minutes, then export out, then in a final file put the clips back together to form a long feature. Basically each "act" of the movie is done as a separate project and then combined at the end. It works great in DV because DV doesn't recompress when just cutting. Of course CFHD does, but this shouldn't be too much of an issue.

The quality when exporting from Vegas as opposed to HDLink is indeed very poor IMO. Same thing if I use VirtualDub. I guess this is consistent with what you're saying - HDLink uses a much better process than the VFW codec. I would send you the original M2Ts but I'm afraid they're all rather huge. They just came straight from the tape. I import entire tapes to entire M2T files (I have a massive 1TB array so I don't care about file sizes). I could try Premier, but I don't really want to learn new software for this project. THe only other thing I could do is change my workflow. I think what I might wind up having to do is simply export each clip uncompressed.

The other thing I do, btw, is 60i->24p conversion using VirtualDub. Thus, even if I use HDLink to compress to CFHD, I still need to use VirtualDub to re-encode it. VirtualDub only supports VFW codecs as far as I know, so if the VFW CFHD codec is not as good as what HDLink uses, then I cannot use it.

Can't you make the VFW codec just as powerful as the one used in HDLink? I cannot even frameserve to HDLink because it only supports M2T files.

The VfW codec is not THAT much different, so I'm looking for examples that demonstrate a problem. The main difference in using VFW is RGB which doesn't quite have the dynamic range of YUV (particularly within VirtualDub which is cgRGB, unlike Vegas's studioRGB.) Yet if you happy with VirtualDub uncompressed output the CineForm output should match. The only other differences are the VFW codec assumes interlaced encoding for 1080i and progressive 720p (this can't be overridden) and the VFW codec is hard coded to medium quality (which hasn't caused any issue in the past.) I would like to confirm which you are seeing, for that I need your source data and the steps in your workflow (such as the 60i->24p within VirtualDub, and are you resizing also, and with what filter, etc?)

Well, we can not worry about all that other stuff. That other stuff is the reason I Need to use Vegas or some other program with VFW to re-compress the footage at some point, but it is not the source of the problem.

In its simplest form, the problem is that M2T data (1080i HDV) straight from the tape looks good when converted to Cineform using HDLink, and looks terrible when converted to Cineform with Vegas using the standard HDV-1080i template. The source material is just too big (multiple gigabytes) to get it to you. But you've seen screenshots. The only other thing that I Can tell you is that the footage is from a Sony Z1. I'm afraid I cannot even copy a tape for you, as I don't have the camera anymore.

I think, and this is just a guess, that Vegas is using a lower qualiy setting on the codec than HDLink. It sure looks that way. Esp. since there's no way to set the quality using the VFW codec (unlike when using HDLink).

You can cut out a piece of the original M2T without re-encoding and send that file to David. That is what he is asking for so he can recreate your problem. The clip doesn't have to be long, maybe 2-3sec tops.

How can I do it without re-encoding? Vegas can't do it.

Most hex editors can do it. Or a tool like http://www.sofotex.com/MiniSplit-download_L16577.html will happy chop up a larger file. Fortunately transport streams can be chopped randomly and the video/audio can still be extracted. I need a segment about 6MB (2Sec).

No kidding!? Ok, gimme 10 minutes and I'll get you your clips.

Ok here you go:

http://www.mooreusa.net/cfhd%2Dtests/

clip.m2t is a 6 MB splice. Now, Vegas cannot read it directly though HDLink can and with HDLink I created cineform-from-hdlink.avi which is very good.

I found the corresponding frames in the original M2T file and with Vegas made some comparisons. For instance I tried huff-yuv which produced pretty good results though the file is huge. I also tried Cineform directly from a Vegas render, and this is by far the worst of the bunch.

To see the worst of the problem, look to the left of center, near the bottom, at the wall. The noise there is excessive. Granted, it's in the original, but MUCH more subtle.

Hope this helps.

For some reason clip.m2t will not download -- everything else will. Could you check the filename.

Sorry, I don't know what that's about. I renamed it to .MPG and it works. Just name it back to M2T after downloading.

So, any ideas now that you've seen the footage?

Seems to only happen in Vegas with dark noisy source elements from the Vegas MPEG decoder -- which we don't recommend you use (as you have found, Connect HD using HDLink does a much better job.) It also doesn't occurs as much less in VirtualDub, or in subsequent CineForm renders out of Vegas, neither of which use the Vegas MPEG decoder. That rules out a DirectShow vs VFW issue -- it also rules out medium vs high quality encoding (as both modes produce excellent results outside of Vegas.) I think we are chasing ghosts here (the noisy MPEG variety.) The noisy 8-bit nature of the video is the primary problem. The region you are having issues with are very dark with Luma level ranging between 20 and 30, with about noise level between 1 and 3, so noise is a huge factor for these very dark regions. Enhancing the source shows clear MPEG macro blocking in the regions affected. The reason Vegas has a slightly harder time is its RGB nature (Aspect HD and Premiere export using YUV as much as possible), so the noise + the low signal + YUV to RGB conversions are most of what you see. Lossy compression is a factor, yet my testing (particularly which change the compression quality) shows that it isn't a significant element. Using uncompressed or HUFFYUV eliminates the color conversion for accurate noise reproduction, so you do have that option of your final masters.

Note: the preview window with Vegas shows the video at the wrong levels, broadcast black (IRE 7.5, Y 16, cgRGB 0,0,0) is displayed at RGB level 16,16,16. This is give you an artificial amplification of shadow noise, that will be far less visible on standard outputs.

I very much appreciate you taking the time to look at this.

So what you're saying is, Vegas' M2T decoder does the poor job? If I keep the source files as Cineform, and then subsequently re-render them using Vegas or other software, there won't be a problem? I'm gonna try that right now, and if so, you have solved my problem.

Yes that is basically it. The "splotchy" was mostly noisy reproduction of an MPEG artifact, yet this is greatly suppressed in HDLink to produce nice images. So if you don't go back to you MPEG source, and stick with CineForm Intermediate you will get better results.

Yeah I am definitely getting better results now, although the 2nd generation Cineform encoding from Vegas still has a noticeable difference from the 1st gen. Is it supposed to be re-encoding from Vegas even with no modifications? Just cuts?

Unfortunately not. Vegas doesn't support the 2 frame GOP structure of the CineForm Intermediate codec for direct copy, so it will re-render to a 1 frame GOP when you export. The third generation (if you were to do that) would be direct copy, as 1 frame GOP are support by Vegas. I think the idea for Vegas users might be an option to select a 1 frame GOP length within HDLink, that cuts only renders are lossless and fast, however this has the downside of creating bigger files and a little slower playback.

That would be nice.

I'm sorry but the pass out of Vegas is just still too splotchy. It's a shame, because the pass out of HDLink is excellent. After my 24p processing in VirtualDub, it's still excellent. But as soon as I output one more CFHD round through Vegas, the splotches are still very bad. Vegas just does not handle this codec correctly.

I tried to make subclips to avoid multiple generations, but Vegas won't even let you use subclips between projects. I guess the only option is to switch to Premier. Down the road, though - have to finish this project first with what I've got. Again, thanks for the help though.

All the urls point to a surprising blue page with a dart target board absolutely unrelated to MiniSplit.

Would any one either suggest a working link or post the file somewhere ?

Thanks

That is odd as the link still works for me. You could just google "MiniSplit" if you browser can't show the page I found.