2.7.1.3. Luma-Only Formats¶
This family of formats only store the luma component of a Y'CbCr image. They are often referred to as greyscale formats.
Note
In all the tables that follow, bit 7 is the most significant bit in a byte.
Formats are described with the minimum number of pixels needed to create a byte-aligned repeating pattern. ... indicates repetition of the pattern.
Y'x[9:2] denotes bits 9 to 2 of the Y' value for pixel at column x.
0 denotes padding bits set to 0.
Identifier |
Code |
Byte 0 |
Byte 1 |
Byte 2 |
Byte 3 |
Byte 4 |
---|---|---|---|---|---|---|
|
'GREY' |
Y'0[7:0] |
... |
... |
... |
... |
|
'ip3y' |
Y'0[7:0] |
Y'1[5:0] Y'0[9:8] |
Y'2[3:0] Y'1[9:6] |
Y'3[1:0] Y'2[9:4] |
Y'3[9:2] |
|
'Y10 ' |
Y'0[7:0] |
000000 Y'0[9:8] |
... |
... |
... |
|
'Y10B' |
Y'0[9:2] |
Y'0[1:0] Y'1[9:4] |
Y'1[3:0] Y'2[9:6] |
Y'2[5:0] Y'3[9:8] |
Y'3[7:0] |
|
'Y10P' |
Y'0[9:2] |
Y'1[9:2] |
Y'2[9:2] |
Y'3[9:2] |
Y'3[1:0] Y'2[1:0] Y'1[1:0] Y'0[1:0] |
|
'Y12 ' |
Y'0[7:0] |
0000 Y'0[11:8] |
... |
... |
... |
|
'Y012' |
Y'0[3:0] 0000 |
Y'0[11:4] |
... |
... |
... |
|
'Y14 ' |
Y'0[7:0] |
00 Y'0[13:8] |
... |
... |
... |
|
'Y16 ' |
Y'0[7:0] |
Y'0[15:8] |
... |
... |
... |
|
'Y16 ' | (1U << 31) |
Y'0[15:8] |
Y'0[7:0] |
... |
... |
... |
Note
For the Y16 and Y16_BE formats, the actual sampling precision may be lower than 16 bits. For example, 10 bits per pixel uses values in the range 0 to 1023. For the IPU3_Y10 format 25 pixels are packed into 32 bytes, which leaves the 6 most significant bits of the last byte padded with 0.
For Y012 and Y12 formats, Y012 places its data in the 12 high bits, with padding zeros in the 4 low bits, in contrast to the Y12 format, which has its padding located in the most significant bits of the 16 bit word.