Quantcast Capture Settings for ATI/AIW Card - digitalFAQ Forum
  #1  
12-07-2009, 09:53 AM
A1driller A1driller is offline
Free Member
 
Join Date: Dec 2009
Posts: 3
Thanked 0 Times in 0 Posts
I have an ATI-AIW card installed on my computer. TV input is satellite from DISH. I went thru the excellent tutorial for capturing MPEG-2 and set my ATI-MMC 9.03 recorder up using the MOVIES template. What I want to do is record football games and when using these setting, they do not seem to be as clear as I would like. Has anyone found better settings for capturing live football games?

Thanks for your help.
Reply With Quote
Someday, 12:01 PM
admin's Avatar
Ads / Sponsors
 
Join Date: ∞
Posts: 42
Thanks: ∞
Thanked 42 Times in 42 Posts
  #2  
12-07-2009, 11:04 AM
admin's Avatar
admin admin is offline
Site Staff | Web Development
 
Join Date: Jul 2003
Posts: 4,338
Thanked 616 Times in 448 Posts
As found on http://www.digitalfaq.com/guides/vid...e-ati-mpeg.htm, the MOVIES template is
  • VBR MPEG2
  • 352x480 @ 3.90Mbps bitrate, with max of 4.0Mbps bitrate
  • at motion setting of 99
  • 256k 48hz audio.
Football, like many other sports, are fast-action, so you'll always need a high bitrate for live MPEG encoding. (The alternative is to capture as AVI, then 2-pass encode to MPEG in a high quality professional MPEG encoder like MainConcept Reference.)

If you feel there is not enough clarity, then bump up to 720x480 @ 8.0Mbps bitrate. At this size, you'll get maybe 1 to 1.5 hours per DVD, however. Or you can maybe get 2.5 to 3 hours on a DVD+R DL, if you burn to dual-layer media.

Lowering audio to 192kbps or 224kbps won't really save any room, and would only lower audio fidelity.

Traditionally, DISH Network is using an approximate 480x480 resolution, which is more or less transparent to 352x480 when viewed. Your clarity issue may be the result of the MPEG compression scheme itself, which can often lead to loss of fine detail.

There is no way to avoid MPEG, if making DVDs. Alternatives to MPEG include AVI capture with post-processing and encode to H.264 or XVID, at higher resolutions and bitrates. But it won't be a DVD-Video compliant file any longer, just computer video files.

Hope that helps. Ask follow-ups if needed.

- Did this site help you? Then upgrade to Premium Member and show your support!
- Also: Like Us on Facebook for special DVD/Blu-ray news and deals!
Reply With Quote
  #3  
12-07-2009, 12:30 PM
A1driller A1driller is offline
Free Member
 
Join Date: Dec 2009
Posts: 3
Thanked 0 Times in 0 Posts
Thank you for reply. The settings you reference are the MOVIE template and I did try that. I believe I would like to have something a little clearer for a recorded football game DVD played on a 50" TV.

If I jump up my resolution to 720x480 @ 8.0 Mbps, should I change any settings on the frame sequence settings? This is one area that I can get confused very quickly. I am set up exactly as you showed in the tutorial.....

I BB P BB P BB I And I have checked the GOP setting.

Thanks again.
Reply With Quote
  #4  
12-07-2009, 10:35 PM
admin's Avatar
admin admin is offline
Site Staff | Web Development
 
Join Date: Jul 2003
Posts: 4,338
Thanked 616 Times in 448 Posts
In MPEG, compression occurs not just in the image, but between images. This in-between compression (known as temporal compression or inter-frame compression) is done with a group of pictures, or GOP.

The GOP compression settings help determine how well bitrate is distributed across the MPEG encode. The I frames holds all data, while the P and B frames only store bits and pieces of data that are different between the the I frames.

However, GOP length also affects the clarity, in regard to compression artifacts. While more P and B frames in a GOP will better distribute bitrate allocation for the I frames, the signal can degrade easier.

The settings suggested in the guide are considered optimal for the live MPEG capture done on this hardware. You're free to experiment with more or less P and B frames. In many cases, you won't see any real difference. In others, there will be a noticeable flux in the image, almost like a flicker, as the data degrades before finding another I frame.

This is a fairly complex portion of MPEG compression.

If you're really interested, the Final Cut Pro documentation has a good read available at the Apple docs site: http://documentation.apple.com/en/fi...ection_33.html

There was also a pretty good article over at Broadcast Engineering a few months ago, concerning long-GOP editing, with some basics and overview on the topic of GOP in general. I actually read it first in the print edition. Read page 1 at http://broadcastengineering.com/hdtv...-editing-0709/ and page 2 at http://broadcastengineering.com/hdtv...09/index1.html


In case links go 404...


Attached Files
File Type: pdf Apple-FCP-GOP-Doc.pdf (204.0 KB, 0 downloads)
File Type: pdf BroadcastEng-LongGOP-Page1.pdf (108.6 KB, 3 downloads)
File Type: pdf BroadcastEng-LongGOP-Page2.pdf (138.1 KB, 2 downloads)

- Did this site help you? Then upgrade to Premium Member and show your support!
- Also: Like Us on Facebook for special DVD/Blu-ray news and deals!
Reply With Quote
  #5  
12-07-2009, 10:48 PM
A1driller A1driller is offline
Free Member
 
Join Date: Dec 2009
Posts: 3
Thanked 0 Times in 0 Posts
Thanks for the links. I will check them out.

I have some other DVD's that look good on my TV. How do I go about finding out what resolution and bitrate these were recorded at? I thought I knew how to find this in Nero, but apparently I do not.
Reply With Quote
  #6  
12-07-2009, 11:07 PM
admin's Avatar
admin admin is offline
Site Staff | Web Development
 
Join Date: Jul 2003
Posts: 4,338
Thanked 616 Times in 448 Posts
You need analysis software for the MPEG files (or VOB files, if already authored into DVD-Video format).

First, analyze the MPEG or VOB file in Gspot v2.52 (not 2.70, it takes too long). You can download it at the official homepage http://www.headbands.com/gspot/gspot252dl.html or attached to this post. Be sure to select a full 1GB (0.99GB) VOB file with video content, not a tiny little menu or other junk file.

Gspot tells you the maximum bitrate specific for the MPEG, as well as the resolution. It also gives some other info, such as interlacing, field order, and audio specs. Notes on this at http://www.digitalfaq.com/guides/vid...nd-sources.htm about halfway down the page.

Next open a file in the attached Bitrate Viewer (File), or a DVD in the drive with the attached Bitrate Viewer (DVD). If you have DVD files on the hard drive, open a VOB file in the File version. These will analyze the full file or DVD, and then tell you the average bitrate that was actually used. It won't just give you the number parameters set in the file, which is misleading. That's what Gspot did (only tell max, not actual used average).

I've not included any images here, but ask if you need more help.

If you're not sure what to do with these ZIP or RAR files, then read this help post.




Attached Files
File Type: rar BitrateViewer-DVD.rar (6.0 KB, 3 downloads)
File Type: rar BitrateViewer-Files.rar (2.64 MB, 2 downloads)
File Type: rar GSpot-v25.rar (182.2 KB, 1 downloads)

- Did this site help you? Then upgrade to Premium Member and show your support!
- Also: Like Us on Facebook for special DVD/Blu-ray news and deals!
Reply With Quote
Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
Used wrong capture settings - how to fix? admin Capture, Record, Transfer 0 11-03-2009 08:41 AM
Looking for used capture card naga Capture, Record, Transfer 6 07-07-2008 09:52 AM
MMC capture settings for ATI x1900 PCI express? groovy Capture, Record, Transfer 7 05-03-2006 02:21 AM
Capture card Wineslurper Capture, Record, Transfer 6 07-12-2005 08:04 AM

Thread Tools



 
All times are GMT -5. The time now is 11:19 PM