Grass Valley EDIUS Pro v.7.4 Reference Manual - Manual (Page 444)

Chapter 11 Interaction with GV STRATUS — Interaction Function with GV STRATUS
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[GOP structure] For MPEG, a certain number of frames is considered as a group, and operations such as
compression/enlargement and cut editing are performed on a GOP basis. A GOP comprises
“I frame”, “P frame” and “B frame”. The I frame allows images to be reproduced independently,
the P frame is for recording and reproducing only the differences with the preceding image,
and the B frame reproduces images from the differences in the preceding and following
images. Select I, P and B frame patterns of the GOP from the list. Normally, select [IBBP].
[I-Frame Only] is comprised of only I-pictures. Editing is made easier, but the amount of data
increases in size.
[Picture count] Set the number of frames included in a group.
[Closed GOP] Check this item to complete information within each GOP. Although the amount of data
increases, the video can be re-edited using software that supports GOP-based editing.
Normally, leave this item unchecked.
[Chroma Format] Select a YUV pixel format from the list.
[Profile/Level] Select a profile & level. If [Chroma Format] is [4:2:0] and [4:2:2], the profile will be set to Main
Profile and 422Profile, respectively. The level for SD image quality will be Main Level, and
the level for HD image quality will be High Level. The profile & level changes according to the
format selected in [Chroma Format].
r Video settings—DNxHD
[Bit Rate] Select a bitrate from the list.
r Video settings—AVCHD
[Profile] Set the profile. The selectable profiles will differ depending on the frame size to be exported.
[Bit Rate Type] [CBR] assigns a constant number of bits. Although noise, etc. may be present, the encoding
process is made quicker.
[VBR] changes the assigned bitrate according to the complexity of the movement or image
quality. Compared with [CBR], the media volume can be used more efficiently, and this enables
more consistent image quality overall.
[Average ] Set this item if [CBR] or [VBR] has been selected as the bitrate type. You can either select from
the list or enter values directly.
[Max] Set this item if [VBR] has been selected as the bitrate type. You can either select from the list
or enter values directly.
[Quality] Set this item if [Quantization] has been selected as the bitrate type. Select the image quality
from the list.
[IDR Interval] Enter the IDR frame interval, and set the GOP size.
[B Frame] Set the number of B-frames included in one GOP.
[Multi Slice] Check this item to divide 1 frame into 4 parts. If the decoder supports multi-slicing, the
decoding may be made quicker.
[Entropy Coding Mode] Select the H.264 encoding mode.
[Number of Reference Frames] Set up to how many frames should be considered when motion estimation is performed.
[Motion Estimation Precision] Select the unit of division for the motion estimation block from the list.
[Minimum Block Size of Prediction] Set the block size during motion estimation for intra-frames/inter-frames.