This help file contains information about some of the dialog boxes in Video Capture. You can access this help file by clicking the Help button in that particular dialog box.


Switch Capture Plug-in dialog box
Change Capture Plug-in dialog box

Current capture plug-in Allows you to choose a plug-in for the capture driver that comes with the capture device you have installed on your computer.

Description Displays a brief description of the selected capture plug-in.


MPEG Settings dialog box

Special settings Select User defined to customize the MPEG capture or select from the list provided for convenient and coordinated settings. You are encouraged to use the NTSC VCD and the PAL VCD settings for creating whitebook compliant MPEG-1 files for use on VCDs.

Capture MPEG type Select MPEG-1 or MPEG-2. These are the two standards for MPEG video. MPEG-1 is the world standard used to produce hundreds of millions of VCDs worldwide and can be viewed on most computers. It has a strict format: 352X240 and 23.97fps. MPEG-2 is a newer standard and is used in DVD discs and produces much higher quality video, if more flexible (variable resolution/frame rate), but also requires a much faster computer.

Half D1 mode Half D1 means 352 pixel horizontal resolution and is the standard resolution that should be chosen for MPEG-1 video, but can also be chosen for MPEG-2 encoding. In many situations, Half D1 resolution produces more than adequate picture quality, especially when viewed on a television screen (which has a much lower resolution than a computer monitor). The file size (and thus the Data Rate) can be significantly lower at Half D1 and can also work much better on slower computers. (Full resolution (NTSC) is 740X480; for MPEG-2 Half D1 is 352X480.)

Video data rate (Kbits/sec) Typical values can range from 1048Kbps to about 6288Kbps. The higher the data rate, the higher the quality and the larger the file size. Higher data rates are also harder for your computer to process.

Capture frame rate Select a frame rate between 23.97 ~ 30. For video that will be viewed on your computer, you can select any frame rate you want, keeping in mind that lower frame rates yield smaller file sizes and lower data rates. If you are recording the resulting video to video tape or out to a television, you need to specify a frame rate that matches your country's standard: e.g. 29.97fps for NTSC or 23.97fps for PAL. MPEG-1 video is typically 23.97 or 24 fps.

Performance Select a value between 1 ~ 15. This sets up the performance of the encoding program. Higher values may yield higher quality video, but will certainly result in slower operation. It is best to use a middle value (like 6 or 7) unless you are experiencing problems. The Performance value determines the behavior of the Motion Estimation algorithm.

Audio Click to set up the details of the audio compression.

Advanced Click to set up the more complicated aspects of the MPEG capture process. Recommended for advanced users only.

  Capture Audio Settings dialog box

  Advanced Settings dialog box


Advanced dialog box
Advanced Settings dialog box

Aspect ratio for MPEG-2 Select the width and height ratio for the captured video. MPEG, especially MPEG-1, can be very picky about acceptable aspect ratios, so please select NTSC VCD or PAL VCD in the MPEG Settings dialog box to automatically set the aspect ratio when creating whitebook VCDs.

I Frames only By selecting this option, the MPEG encoder will only compress the video to something called I frames (and not P or B frames). In simple English, this means that the quality of the file will be better, but that the file size will be much larger. For most people, you should leave this option unselected, as it disables an important part of MPEG compression.

Number of P Frames Select this to compress intermediate P frames. P frames occur between I frames and are based on the surrounding two I frames. Selecting to use I and P frames (but not B) MAY yield higher quality, but will certainly increase overall file size. Good values to try here are 2 or 3 (default).

Number of B Frames Select this to compress intermediate B frames (recommended). A good range of value here should be between 6 and 12.

Closed GOP count GOP stands for Group Of Pictures and you can tweak the encoding process by creating larger or smaller groups.

Bit rate type A Constant bitrate is required for whitebook MPEG-1, but if you are encoding MPEG-2 files you may see a dramatic increase in quality as well as a shrinking of the file size by choosing Variable bitrate. This allows the encoder to apply greater compression to sections of your video with little or no movement and less compression (higher bitrate) to sections with a lot of motion.

  MPEG Settings dialog box


Capture Audio Settings dialog box

Mode Choose from Mono, Stereo, Dual channel, or Joint stereo.

Audio bitrate Select an overall quality for the file.

Sample rate This is the frequency of the audio sample and, when combined with bitrate, determines the quality of the audio: CD quality is 44.1kHz. In many cases, 22kHz produces very high quality and better compression for MPEG-1 files.

  MPEG Settings dialog box