Grass Valley ProCoder 3 User Manual
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ProCoder 3
Aspect Ratio Code
The Aspect Ratio Code tells the decoder what the intended display frame size is.
VBV Buffer Size (KB)
Specifies the video buffer verifier size in kilobytes. This is used by the encoder to
ensure the stream can be properly decoded by hardware players.
Max GOP size
Sets the maximum GOP (Group Of Pictures) size. Larger GOPs provide better
compression while smaller GOPs provide faster access.
GOP Structure
Specifies the maximum distance between I and P frames, which determines the GOP
(Group Of Pictures) structure.
Automatic
Sets the GOP structure automatically based on the content.
I-Frame only
Creates output without P and B frames.
1 frame (IPPP ...)
Creates output with a maximum of 1 frame from I to P frames.
2 frames (IBPBPBP...)
Creates output with a maximum of 2 frames from I to P frames.
3 frames (IBBPBBP...)
Creates output with a maximum of 3 frames from I to P frames. This
is the standard for DVD-compliant MPEG streams.
Enable Scene Detection
When scene detection is enabled, the encoder distributes the available bandwidth
better by splitting GOP over scene changes. For best quality, it is recommended to
keep this option enabled.
Picture Structure
The compression process can compress interlaced fields separately or combined as a
frame to improve efficiency. This option sets the picture structure for the compression
process. This is does not affect the interlacing mode of the output.
Always Field
Always compress interlaced fields separately. This option should be
avoided except in special circumstances.
Always Frame
Always compress interlaced fields together as frames. This method
is compatible with all known DVD players.
Automatic
Selects the optimal mode for each frame. The output may not play
correctly in all players.
Use Closed GOP
Enable this option to encode closed GOPs. Closed GOPs do not allow prediction
between frames at the ends of GOPs. Some DVD-authoring software requires Closed
GOPs, as does multi-angle DVD content.