User`s guide

40 007-4403-003
3: System Configuration
For example, Table 3-4 defines examples of valid GOP sizes, their periods, and structures.
To enable MPEG-2 video compression with the default I-frame compression and GOP
size 1, add the following line to the appropriate MFCODEC_n file:
vtr.media.video.input.compression.type mpeg2
Alternatively, you can use the SET command from mvcp to apply it directly in the unit
context. To further compress and encode a video stream, add the following lines:
vtr.media.video.input.compression.type mpeg2
vtr.media.video.input.compression.gop_structure IPBB
vtr.media.video.input.compression.gop_size 6
Caution: Selecting unreasonable values for
vtr.media.video.input.compression.gop_size may lead to unpredictable
results. A maximum gop_size of 15 is considered an extreme upper bound for the
MFCODEC.
The MFCODEC further supports two distinct forms of compression sampling: 4:2:0 and
4:2:2. The control vtr.media.video.input.compression.sampling has a default
value of 422, which selects 4:2:2 compression sampling. To enable 4:2:0 compression
sampling, add the following line to the appropriate MFCODEC_n file:
vtr.media.video.input.compression.sampling 420
Alternatively, you can use the SET command from mvcp to apply it directly in the unit
context.
Table 3-4 Example GOP Size, Period, and Structure
Size Period Stored GOP Structure
11 I
15 1 IPPPPPPPPPPPPPP
6 3 IBBPBB
15 3 IBBPBBPBBPBBPBB
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