2.6.27. V4L2_PIX_FMT_NV16 (‘NV16’), V4L2_PIX_FMT_NV61 (‘NV61’)¶
V4L2_PIX_FMT_NV61
Formats with ½ horizontal chroma resolution, also known as YUV 4:2:2.
One luminance and one chrominance plane with alternating chroma samples
as opposed to V4L2_PIX_FMT_YVU420
2.6.27.1. Description¶
These are two-plane versions of the YUV 4:2:2 format. The three
components are separated into two sub-images or planes. The Y plane is
first. The Y plane has one byte per pixel. For V4L2_PIX_FMT_NV16
, a
combined CbCr plane immediately follows the Y plane in memory. The CbCr
plane is the same width and height, in bytes, as the Y plane (and of the
image). Each CbCr pair belongs to two pixels. For example,
Cb0/Cr0 belongs to Y’00, Y’01.
V4L2_PIX_FMT_NV61
is the same except the Cb and Cr bytes are
swapped, the CrCb plane starts with a Cr byte.
If the Y plane has pad bytes after each row, then the CbCr plane has as many pad bytes after its rows.
Byte Order. Each cell is one byte.
start + 0: | Y’00 | Y’01 | Y’02 | Y’03 |
start + 4: | Y’10 | Y’11 | Y’12 | Y’13 |
start + 8: | Y’20 | Y’21 | Y’22 | Y’23 |
start + 12: | Y’30 | Y’31 | Y’32 | Y’33 |
start + 16: | Cb00 | Cr00 | Cb01 | Cr01 |
start + 20: | Cb10 | Cr10 | Cb11 | Cr11 |
start + 24: | Cb20 | Cr20 | Cb21 | Cr21 |
start + 28: | Cb30 | Cr30 | Cb31 | Cr31 |
Color Sample Location:
0 | 1 | 2 | 3 | |||
0 | Y | Y | Y | Y | ||
C | C | |||||
1 | Y | Y | Y | Y | ||
C | C | |||||
2 | Y | Y | Y | Y | ||
C | C | |||||
3 | Y | Y | Y | Y | ||
C | C |