THOMSON ViBE VS7000, Руководство пользователя

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Chapter 3 ’Web Browser Interface’ — Workflow Library Content Parameters
ViBE VS7000 127
User Manual
For this item, you must set the following parameters:
„
Bitrate : enter the bit rate value (without encapsulation overhead), in
bits per second.
„ Profile : select from the drop-down list the profile you wish to apply:
™ Baseline : simplest profile in H.264; B pictures and CABAC are
not encoded. It is used for low resolutions. In this case, also set
the following parameters:
- Frame structure : choose from the drop-down list the way
you want to handle interlaced streams. Possible options
are:
- Progressive : the whole frame is encoded. This mode is
suitable for IP TV 720p and Web TV.
- Interlace : fields are encoded separately. This mode is
suitable for IP TV SD and 1080i.
Make sure that this respects the format of the input
connected to the
H.264 AVC encoder item.
- P period :
- 1 if the GOP contains no B frame
- 2 if a B frame is present between each P frame
- 3 if two B frames are present between each P frame
- etc.
- Hierarchical GOP : if set to true , B frames can be used as
references.
- Closed GOP period : set to 0 for no periodicity, 1 for every
GOP, 2 for every second GOP, etc.
™ Main : generally used for SD resolutions.
™ High : generally used for HD resolutions.
„ Level : select from the drop-down list the level you wish to apply.
„ Mode : select an encoding mode:
™ Premium : this encoding mode provides the best video quality.
™ High-density : this encoding mode provides the best density (it
uses less CPU and thus allows to perform more encodings).
„
Display Aspect Ratio : leave to Auto to keep the source display aspect
ratio. If you want to use another ratio, enter it manually in the editable
list.
„ I period : maximum size of the GOP.
„ Adaptive GOP : if set to false , GOPs always have the same structure. If
set to true , the scene cut detection feature is used and the GOP
structure is modified consequently. Adaptive GOP is always the best
choice regarding video quality, even for Web TV adaptive bitrates.