doc.: ieee 802. 15-08-0145-01-003c submission march, 2008 etrislide 1 project: ieee p802.15 working...
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doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 1
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [Description on current UEP problems and the resolutions to the problems]Date Submitted: [March 18, 2008]Source: [Seung-Eun Hong1 , Yongsun Kim2, Wooyong Lee3, Jinkyeong Kim4, Kyeongpyo Kim5, Hyoungjin Kwon6]Company: [Electronics and Telecommunications Research Institute (ETRI)]Address: [ETRI, 161 Gajeong-dong, Yuseong-gu, Daejeon, 305-700, Republic of Korea]Voice: [], FAX: [], E-Mail: [[email protected] 1, [email protected], [email protected], [email protected], [email protected], [email protected]]Re: []Abstract: [We describe current UEP problems in DF1 and propose resolutions to the problems.]Purpose: [To be considered in IEEE 802.15.3c standard]Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 2
Overview• Problems of Current UEP Process
– Current UEP only supports a pixel data with 8/8/8 bit depth• Needs to support video data with various bit depths such as
16/16/16
– Current UEP is not optimized to various video formats• UEP can be applied to YCbCr as well as RGB color format• In case of YCbCr, current UEP scheme may not be optimized
because Y is more important than CbCr.• UEP for compressed video can also be considered
• New Proposal of UEP process– Considers color depths and color format of the video data– supports the bit position for separation of MSBs and LSBs
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 3
Current UEP Process• Separates MSBs and LSBs according to fixed
bit position of a pixel data with 8/8/8 bit depth– Different FEC coding rates (or MCSs) can be
applied to MSBs and LSBs, respectively– UEP mapping can be applied in order to weight
MSBs and LSBs differently
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
Problems of Current UEP• Current UEP process supports only fixed color
depth of 8 bits (comment 48 & comment 49 in DF1)– Not support various color depths
– Not indicate bit position to separate MSBs from LSBs
Using Current UEP
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 5
Problems of Current UEP• Current UEP is not optimized to various video
format• In case of YCbCr, video quality may not be
optimized because even LSBs of Y might be more important than MSBs of Cb/Cr (comment 50 in DF1)
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 6
Proposed Resolution to Comment 48 & 49
• Method 1: During UEP negotiation, required information, such as color depth, bit position and color format, is delivered in advance
• Method 2: Like subframe information and UEP mapping indication field in MAC subheader, the color depth and bit position fields are included in the subheader – ETRI prefers method 1 to method 2 because method 2
requires much overhead in every single frame
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 7
Proposed Resolution to Comment 48 & 49
• Method 1: UEP negotiation – Current UEP Information Request/Response Command
– Suggested UEP Information Request Command
1
MCS request/response -1
2
Length
2
Command type
1
UEP Type
...
...
Octets: 1
MCS request/response -n
MCS request/response -1
Length
2
Command typeUEP Type Color depthBit separation
point
2... 311
...
Octets: 1
MCS request/response -n
1
Color format
1
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 8
Proposed Resolution to Comment 48 & 49
• Method 1: UEP negotiation (cont’d) – Example of Color (pixel) depth field
hex valueColor (pixel) depth
(R:G:B or Y:Cb:Cr)
0x00 4:2:2
0x01 4:4:4
0x02 5:6:5
0x03 8:8:8
0x04 16:16:16
0x05 24:24:24
0x06 ~ 0xFF Reserved
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 9
Proposed Resolution to Comment 48 & 49
• Method 1: UEP negotiation (cont’d) – Example of bit separation point field
hex valueb7-b0
Bit position(R or Y)
hex valueb8-b15
Bit position(G or Cb)
hex valueb16-b24
Bit position(B or Cr)
0x00 ~ 0xFF 0: all bits are MSB,
0<n<X: (b0-bn-1)=LSB, (bn-bX-1)=MSB,
X: all bits are LSB
X+1 ~ 255: reserved
X is color depth
0x00 ~ 0xFF 0: all bits are MSB,
0<n<Y: (b0-bn-1)=LSB, (bn-bY-1)=MSB
Y: all bits are LSB
Y+1 ~ 255: reserved
Y is color depth
0x00 ~ 0xFF 0: all bits are MSB,
0<n<Z: (b0-bn-1)=LSB, (bn-bZ-1)=MSB
Z: all bits are LSB
X+1 ~ 255: reserved
Z is color depth
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 10
Proposed Resolution to Comment 48 & 49
• Method 1: UEP negotiation (cont’d) – Example of color format field
hex value Color format
0x00 RGB
0x01 YCbCr
0x02 ~ 0xFF Reserved
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 11
Proposed Resolution to Comment 48 & 49
• Method 1: UEP negotiation (cont’d) - summary
MCS request/response -1
Length
2
Command typeUEP Type Color depthBit separation
point
2... 311
...
Octets: 1
MCS request/response -n
1
Color format
1
Hexvalue
Color format
0x00 RGB
0x01 YCbCr
0x02-FF Reserved
Hexvalue
Color depth(X:Y:Z)
0x00 4:2:2
0x01 4:4:4
0x02 5:6:5
0x03 8:8:8
0x04 16:16:16
0x05 24:24:24
0x06-FF Reserved
Hexvalue
Separation Point for X
Hexvalue
Separation Point for Y
Hexvalue
Separation Point for Z
0:All bits are MSB
0<n<X:(b0-bn-1)=LSB(bn-bX-1)=MSB
X:All bits are LSB
X+1~255:Reserved
b7-b0:
0x00 ~ 0xFF
0:All bits are MSB
0<n<Y:(b0-bn-1)=LSB(bn-bY-1)=MSB
Y:All bits are LSB
Y+1~255:Reserved
b15-b8:
0x00 ~ 0xFF
0:All bits are MSB
0<n<Z:(b0-bn-1)=LSB(bn-bZ-1)=MSB
Z:All bits are LSB
Z+1~255:Reserved
b23-b16:
0x00 ~ 0xFF
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 12
Proposed Resolution to Comment 50• Color format-based separation of MSBs/LSBs
– Unlike RGB color format, the luminance is more important than chrominance in YCbCr color format
– For example, Y can be MSBs, and Cb/Cr can be considered as LSBs if bit separation point field is used.
Y Cb Cr
8 8 8
4:4 4:4 4:4
MSBs LSBs
Y Cb Cr
8 8 8
Video component
Color depth in bits 8 8 8
MSB bits:LSB bits
doc.: IEEE 802. 15-08-0145-01-003c
Submission
March, 2008
ETRISlide 13
Conclusion
• It is recommended to include fields for bit separation point, color depth and color format in UEP command frame to support various bit depths and color formats
• If we use the bit separation point field, it’s possible to make luminance more weighted than chrominance