Grass Valley PDR v.2.2 - Manual (Page 287)

Configuring a Controller
Profile Family 269
Figure 142. Edit Compression Presets dialog box
- Min Lum Q sets the minimum compression that can be applied to
luminance in a field to meet the target data rate (typically 0.75). The
lowest rate is 0.75.
- Max Chroma sets the maximum compression that can be applied to
chrominance in a video field to meet the target data rate (typically 60).
- Fixed Q sets a fixed picture quality and ignores variation in field size. Use
this mode for critical multi-generation work. When Fixed Q is selected,
the other fields become fixed as Lum Q (fixed luminance compression)
and Chroma Q (fixed chrominance Q). Useful starting values for Fixed Q
and Chroma Q are 5.00. Verify there is sufficient available data rate
headroom before using Fixed Q mode. The bytes/field target attempts to
Table 10. Factory set values of the compression presets
Preset
Name 525/60 Standard 625/50 Standard
Lum Chroma Byte Rate Lum Chroma Byte Rate
Highest 0.75 60.00 100000 0.75 100.00 120000
Best 0.75 60.00 75000 0.75 100.00 90000
Lowest 0.75 60.00 50000 0.75 100.00 60000
Custom 5.00 5.00 5.00 5.00