Quality loss after rotating video at DVinfo.net

Go Back   DV Info Net > Windows / PC Post Production Solutions > What Happens in Vegas...

What Happens in Vegas...
...stays in Vegas! This PC-based editing app is a safe bet with these tips.


Reply
 
Thread Tools Search this Thread
Old June 28th, 2010, 12:20 PM   #1
Major Player
 
Join Date: May 2004
Location: hungary
Posts: 462
Quality loss after rotating video

Hello!

I need to rotate very small my HDV video, about 1 degree. I do this with video event pan/crop.
The source video look sharp.
After rotated and rendered to HDV template (best quality video setting), the sharpness, details
disappear. It has a soft look. I thinked it is because in digital world, it has to be some degrading, nothing is for free. But then i test to render to uncompressed avi and that rotated avi look as sharp as the source.
What can i do? Why is this behavior?
Unfortunately I need the video in HDV format. It is just because the mpeg recompress?
When i change the opacity to 99%, and render it without rotating, there is also recompress but the sharpness remain good!

thx!
Marton
__________________
Relaxing clips with waterfalls and music, 3D photos, 3D videos:
www.3d-video.hu
Prech Marton is offline   Reply With Quote
Old July 7th, 2010, 11:17 AM   #2
Regular Crew
 
Join Date: Feb 2007
Location: Bothell, Washington
Posts: 195
this is a good question. anyone else have comments? i have some shot video of se alaska mountains and shoreline that is slight off, and needs to be rotated serveral degrees...process? quality loss if any with cineform int. codec?
William Boehm is offline   Reply With Quote
Old July 7th, 2010, 12:55 PM   #3
Trustee
 
Join Date: Dec 2002
Location: Gwaelod-y-garth, Cardiff, CYMRU/WALES
Posts: 1,215
Well, if you rotate an image, you're going to have to slightly enlarge it as well, to hide the black edges that you'll get, so there is bound to be a quality loss. It's the same as if you use a software image stabilizer...
Plus the fact that mpeg doesn't like a lot of tweaking in post. A transcode to something like Cineform might be the answer.
Robin Davies-Rollinson is offline   Reply With Quote
Old July 7th, 2010, 03:47 PM   #4
Regular Crew
 
Join Date: Jun 2006
Location: New Zealand
Posts: 63
Does switching on Reduce Interlace Flicker for the rotated clip make any difference?
Mark Sudfeldt is offline   Reply With Quote
Old July 7th, 2010, 04:14 PM   #5
Regular Crew
 
Join Date: Feb 2007
Location: Bothell, Washington
Posts: 195
i am using neoscene 5.04 intermediate codec, and wondering if i should rotate then in vegas 9 under pan, and save to what kind of file...i actually dont know if i can save to a cineform file codec still while in vegas using cineform files. .newbie..just started editing in the past month.
William Boehm is offline   Reply With Quote
Old July 7th, 2010, 05:34 PM   #6
Major Player
 
Join Date: Dec 2009
Location: Rochester,NY USA
Posts: 282
Cineform is also a lossless codec, you would want to save it to Cineform to retain your high quality video.
Bruce Phung is offline   Reply With Quote
Old July 8th, 2010, 10:06 AM   #7
Regular Crew
 
Join Date: Feb 2007
Location: Bothell, Washington
Posts: 195
i havent checked yet..meaning that vegas 9 will let me edit the cineform file, and save back to a cineform file after editing instead of a .veg file?
William Boehm is offline   Reply With Quote
Old July 8th, 2010, 11:31 AM   #8
Major Player
 
Join Date: Dec 2009
Location: Rochester,NY USA
Posts: 282
You got it all confused. The .veg file will always remain the same regardless of what codec is being used. The rendering and the codec that maintian the video is what you are after.
Bruce Phung is offline   Reply With Quote
Old July 8th, 2010, 02:32 PM   #9
Regular Crew
 
Join Date: Feb 2007
Location: Bothell, Washington
Posts: 195
bruce..please explain as i am pretty new at editing in vegas and cineform. my virutal dub download doesnt recognized veg files. so i probabl should deshake footage first, otherwise, edit in vegas, save the file in .veg, then render to a dvd hd in .veg? i need a little explanation if you have time. bill
William Boehm is offline   Reply With Quote
Old July 8th, 2010, 03:26 PM   #10
Major Player
 
Join Date: Dec 2009
Location: Rochester,NY USA
Posts: 282
.Veg file will open by Vegas only. You can not use any other program to open .veg file. .Veg file is the Vegas project name itself. 1) Edit your footage, do what ever you want done to your video 2) when you are finished your edit and happy with it and then render it to AVI. 3) Click on custom and select your codec, in your case you would want to select cineform and click ok. 4) finish your rendering. From there you would import your video into Virtual Dub and deshake it or what ever filter you want to use. When you are finish and you would to render or export to AVI again and select your Cineform codec again. This way your video will always be lossless regardless how many times you have been rendering your video. It like a master video file. If you want to output to Blu ray then output to BD. If you want to output to DVD, then select your DV tempate for DVD. You follow me now?.
For example if you render in Vegas to WMV HD or what ever format. Now you have a video file. And you import that WMV HD file into Vegas, make changes or what ever, and then you render your video again, that will cause your video quality loss after many generations. With a lossless codecs, no matter what you do, your video will always be high quality. Cineform is your choice here. Hope this explaination make sense to you. Good luck
Bruce Phung is offline   Reply With Quote
Old July 8th, 2010, 08:21 PM   #11
Regular Crew
 
Join Date: Feb 2007
Location: Bothell, Washington
Posts: 195
thanks bruce that explains it. you would put virtual dub deshaker at the end then after rotating if needed on some not horizontal images, color correction, brightness contrast, the deshake? i will try this approach. bill
William Boehm is offline   Reply With Quote
Old July 8th, 2010, 08:34 PM   #12
Major Player
 
Join Date: Dec 2009
Location: Rochester,NY USA
Posts: 282
I have spent more than 8 hrs playing with varies setting in deshaker and I never able to get good results. I have seen some impressive video that has been deshaked, but it ain't work for me. I use Virtual Dub mainly for HD to SD down conversion and the result is very impressive, very sharp pictures.
Bruce Phung is offline   Reply With Quote
Old July 9th, 2010, 01:26 PM   #13
Major Player
 
Join Date: May 2004
Location: hungary
Posts: 462
Robin, thanks for your post.
But my video was only rotated, but NOT upscaled!
I masked out the edges with black.
Now i try render to avi frameserver and encode to mpeg with different program.
__________________
Relaxing clips with waterfalls and music, 3D photos, 3D videos:
www.3d-video.hu
Prech Marton is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Windows / PC Post Production Solutions > What Happens in Vegas...

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 01:20 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network