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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 kbps to 384 kbps.
Video Shape
Instant DVD+MP3 allows video capture in 4:3 (standard screen) aspect ratio or 16:9 (wide
screen) aspect ratio from wide screen video sources. You can now create a Wide screen
DVD with this option when you capture video from wide screen video sources.
Use Variable Bitrate (Record)
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+MP3 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
Instant DVD+MP3 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.