Autodesk 64006-051108-9001 User Guide - Page 72

64 Chapter 6: Pre-processing Display Size Control the scale at which the image displays. Although scaling results in a degradation of image quality, this may be an acceptable compromise in cases where you need to minimize file size. For example, you could create output at half the size at which you want it to display, and then set the display size to scale it to twice its size on the output device. The display size choices are: •Normal - displays the image at its normal size. •150% - displays the image at 150% of its normal size. •Double - displays the image at twice its normal size. •Custom - displays the image at the pixel dimensions you enter in the numeric fields that appear when you choose this option. De-interlace Each NTSC or PAL video frame consists of alternating bottom and top fields. A television draws one field every 1/59.94 of a second for NTSC and every 1/50 of a second for PAL. Our eyes put the two alternating fields together to create 29.97 whole NTSC frames per second or 25 whole PAL frames. Most people cannot perceive the interlaced nature of the image on a television screen. Because interlacing creates two unique fields for each final frame, quickly moving areas in the video often become separated into alternating lines that look like the teeth on a comb when displayed on a computer monitor. To obtain the best results for desktop playback, you should de-interlace full-screen video prior to encoding. This removes the interlacing effect which makes it look and encode better. Note: If you are capturing video at half-screen resolution, you do not need to de-interlace the video. The capture card de-interlaces the video as it is captured. De-interlacing Options Cleaner offers three methods of de-interlacing video, plus an option for handling movies originally shot on film. For best results when de-interlacing, you should always capture your source at full-screen resolution. Blend - blurs the top and bottom fields together to produce a smooth, combined image. Using the Blend option with movies containing fast motion may produce smoother apparent motion because this option preserves the motion blur effect of interlacing. However, this option may degrade encoding because it has the effect of adding more change to the image.