HD to SD Downconversion

[Dominik Seibold]

Originally Posted by Peter Kraft

Dominik, would you say that MpegStreamClip also does a good downscaling HD > SD? Do you know which algorithm is applied (the famous Lanczos)?

I am asking coz I intend the use Cinema Craft encoder right after New Year, they offer a Compressor plug in now.

I don't know the exact method, but it produces a bit aliasing. In my opinion Compressors rescaling is better. Here's an example, which I previously posted in this forum. Upper one is streamclip, lower one is compressor. The black bars are produced by streamclip because of a reason I don't know.

[Peter Kraft]

Danke sehr!

[Erik Phairas]

I couldn't stand it I had to post...LOL I know nothing about this but this is what I did.

I did a MXF full res 1980x1080 edit, rendered as full res MXF.

Reset project to NTSC DV widescreen 720x480, EX detail off and on, rendered as a DVD architect 720x480 widescreen mpg.

Pulled the mpg back into the timeline and snapped these.

[Vincent Oliver]

Thank you Eric, for posting the two sample pictures.

After much experimentation and trying out most, if not all, of the suggestions made by contributors to this thread, I have found the best solution for producing DVDs.

From the Sony Clipbrowser 2.01 select a clip and Export it as a MXF for NLE and drop the resulting MXF file directly into your NLE applications timeline. With your editing completed send the file out to your DVD authoring application, result = superb detailed SD DVD production.

Over the last four days I have created about 25 test DVDs using a combination of suggested workflows and my own. The Export as AVI DV from clipbrowser 2.01 produced a soft mushy picture. The downconvert to SD from the EX3 produced a similar result, although slightly better than the AVI DV, but still didn’t do justice to the EX3.

It strikes me as odd that many people are adopting a complicated, or time consuming work around, when this camera offers a fast time saving workflow, i.e. direct recording to memory card. The MXF to NLE adds an extra step, but the end result is superb.

I have had the camera for four days now and despite my initial disappointment , it is now producing the result I was hoping for. I still have a few other problems to sort out, i.e. blurry panning, but this could be down to me and my panning speed etc. I will start a new thread on this subject.

Thank you all for taking the time to offer your advice and suggestions, it is much appreciated.

Seasonal best wishes to you all.

[John Peterson]

Originally Posted by Vincent Oliver

Thank you Eric, for posting the two sample pictures.
From the Sony Clipbrowser 2.01 select a clip and Export it as a MXF for NLE and drop the resulting MXF file directly into your NLE applications timeline. With your editing completed send the file out to your DVD authoring application, result = superb detailed SD DVD production.

You aren't sending MXF to the authoring application so what are your project settings and render settings?

John

[Vincent Oliver]

No, I just select export to MXF NLE and save the file to a new folder, in Premierre I start a new EXCAM EX project and import the MXF file. I export the finished project file using the Adobe Media Encoder. Open up Encore and import the file - simple as that. The quality is stunning, I have produced many DVDs in the past using stadard DV tapes etc. I am comparing the quality next to these. I still think there is room for some improvement, especially with the panning shots, but I think this is another issue.

[Paul Kellett]

Vincent, are you using premier pro cs3 or cs4 ?
If so then you don't even need to rewrap the files to mxf, just copy them to your pc.
Use clip browser to copy, drag and drop from the top explorer widow to the bottom window/destination folder.

But apart from that you're doing the same as me, i use vegas and dvd architect, nice and simple, good results.
I also cannot understand why people are going through multiple programs to get good dvd's.

Paul.

[Vincent Oliver]

Paul,

Yes, I know that you can just drop the files directly into Premierre (I am using CS3), but |I was having problems with my Matrox RT X2 card and MPEG files, I was getting a strange frame every now then have a look here.

http://www.dvinfo.net/conf/attend-wo...s-problem.html


This is why I decided to use the EXCAM EX project rather than the Matrox HD project. Having said that the fault still occurs in Matrox HD but not in EXCAM EX projects. I am trying to find a sollution to this through the Matrox help line, but in past experience I will be waiting for a long time for a reply.

I agree with you that there seems to be so many unecesary work arounds about, when it should be an easy process.

Thanks for your reply

[Bill Ravens]

I agree with Vincent, with a caveat. Softness has never, ever been a problem for me. Downconverts with a quality downconverter yields results considerably better than native DV source files. However, I experience line twitter/jitter....that flashing that happens when horizontal lines in the image move vertically inside the frame. This is a vexing problem. I just don't understand what the big bruhaha is over softness since I don't see it. I always work with Cineform intermediates, so, perhaps this softness issue is related to Long Form GOP, donno, doncare.

Does anyone else experience line twitter? Speak up or forever hold your flicker.

[Perrone Ford]

Originally Posted by Bill Ravens

Does anyone else experience line twitter? Speak up or forever hold your flicker.

The only time I've ever seen it was working on someone from this site's problematic footage. But it was interlaced and clearly sharpened in-cam.

[Perrone Ford]

Originally Posted by Vincent Oliver

It strikes me as odd that many people are adopting a complicated, or time consuming work around, when this camera offers a fast time saving workflow, i.e. direct recording to memory card. The MXF to NLE adds an extra step, but the end result is superb.

Not everyone uses the software you do, and others who have used this workflow have had poor results. Hence this thread. I am pleased you have a simple workflow that works for you now.

[Bill Ravens]

interesting...thanx Perrone.

[Erik Phairas]

Originally Posted by Bill Ravens

Does anyone else experience line twitter? Speak up or forever hold your flicker.

That sample I posted, if you watch the actual video (I didn't upload the video) I shot that scene because of the bright background and all the fine detail. I was trying to reproduce the twitter. You could see it in some of the diagonal leaves and stems but it was worse with detail on.

Honeslty detail on did make the whole video appear more 3d, but it had more twitter so I guess it depends on what you want.

[Perrone Ford]

Bill, my suspicions are that we have a few things going on.

1. People are sharpening in camera which is certainly going to add twitter.

2. The re-scalers in some of these NLEs and Authoring programs are not using the best methods to resize images and thus things are going soft.

The idea of the workflow I outlined is to perform each step discreetly so the source of the issue could be determined. For those that can get end-to-end with no problems, this is not helpful. But for those who are getting soft images or twitter, and don't know where or why, the workflow can show at which step the problem is occuring.

[Dominik Seibold]

Originally Posted by Perrone Ford

The re-scalers in some of these NLEs and Authoring programs are not using the best methods to resize images and thus things are going soft.

the main-problem with bad rescalers isn't softness, but aliasing. It looks like sharpness but actually it is information-loss.