Matrox Axio Installation And User Manual page 125

Matrox Custom
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number when calculating the quantization coefficient. In some cases, this
setting may yield less artifacts in graphics.
Under DC Precision , select the bit-depth precision of the DC intra block.
5
¦ Note The higher the DC precision value that's used to capture or render
your video, the more likely that the DC content will be increased at the expense
of the AC content in the encoded stream. This may result in lowering the
overall quality of the compressed stream at a specified data rate.
Under Zig Zag Type , select one of the following:
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Regular
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coefficient of the DCT block as defined in the ISO/IEC 13818-2 (figure
7-2) specification documentation.
Alternate
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of the DCT block as defined in the ISO/IEC 13818-2 (figure 7-3)
specification documentation. Use this setting when capturing or rendering
video at a high data rate (that is, at a data rate of about 50 Mb/sec for SD
video, or 100 Mb/sec or higher for HD video).
7 Select the Force Frame-based DCT setting to render macroblocks as
frames rather than as fields. In some cases, graphics will yield less artifacts if
this option is selected.
Click OK to save your settings.
8
Truncates the AC coefficients to the lowest whole
Sets the regular (default) zig zag scanning pattern of the AC
Sets an alternate zig zag scanning pattern of the AC coefficient
Selecting your MPEG-2 I-frame settings
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