ADS Technologies CD or DVD Hardware manual Use Variable Bitrate, Video Preprocessing Filters

	Format	Video Bit Rates	Audio Bit Rates
VCD		1.15 Mb/sec.	224 kbits/sec.
SVCD		1.5 Mb/sec. - 2.5 Mb/sec.	128-384 kbits/sec.
DVD		2 Mb/sec. – 5 Mb/sec.	192 – 448 kbits/sec.

Audio Bit Rates

The audio format is always compressed in MPEG-1 Layer 2 audio. CapWiz also automatically sets the audio sampling rate to 44.1 Khz for VCD and SVCD settings and 48 Khz for DVD video. We give you the choice to select the audio bit rate for your custom video captures in the range from 192 kbits/sec to 384 kbits/sec.

Use Variable Bitrate

Capturing with variable bit rate will result in overall smaller file sizes than using constant bit rates. When the Variable bit rate setting is enabled Instant DVD examines the frames of video being captured and will automatically increase the bit rate in areas of fast motion or action and decrease the bit rate in areas where not much is changing. This will result in improved overall

quality and an overall smaller file size. The default capture settings are set to constant bit rate.

Video Preprocessing Filters

DVD Xpress includes video preprocessing filters which provide the ability to remove some of the noise found on old video tapes, TV reception or other noisy video sources.

Spatial Filtering

This refers to filtering pixel data that are all located in the same video frame. The Spatial filter is a low-pass filter. This filter removes part of the high frequency noise components. Too much filtering can reduce image sharpness to the point of looking very smooth or blurry. The selection range for this filter is from 0 to 7.

Temporal Filter

This filter processes pixel data that are located in the same pixel coordinates but across two frames of video, usually the current video frame and the previous frame. Because of motion in video sequences, and object located in one position may have moved in the next video frame. Thus, if there is a log of motion, temporal filtering may cause blurring or introduce other artifacts. The selection range for this filter is from 0 to 255.What is the best filter to use for your video? There is no magic formula, you will need to experiment with different filter settings and pick the filter level that removes noise but does not create blur.

Use Deinterlacing (Preview/Playback)

The MPEG-2 software playback codec that we use does not de-interlace video by default. Interlaced video will show horizontal lines when you preview or playback the video. This interlacing does not affect video quality. All NTSC and PAL video is interlaced. You will not see the interlacing when playing back a DVD disk on TV. De-interlacing the video during preview and playback makes the video quality look better on the computer screen. The default capture settings have de- interlacing turned on by default. De-interlacing the video takes a bit more CPU processing power. Some slower PC’s may experience jerky video. In the custom settings, you have the ability to enable or disable de-interlacing. Experiment with your system and your personal preferences to

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