FOURCC.org - Video Codecs and Pixel Formats

YUV pixel formats

YUV formats fall into two distinct groups, the packed formats where Y, U (Cb) and V (Cr) samples are packed together into macropixels which are stored in a single array, and the planar formats where each component is stored as a separate array, the final image being a fusing of the three separate planes.

In the diagrams below, the numerical suffix attached to each Y, U or V sample indicates the sampling position across the image line, so, for example, V0 indicates the leftmost V sample and Yn indicates the Y sample at the (n+1)th pixel from the left.

Subsampling intervals in the horizontal and vertical directions may merit some explanation. The horizontal subsampling interval describes how frequently across a line a sample of that component is taken while the vertical interval describes on which lines samples are taken. For example, UYVY format has a horizontal subsampling period of 2 for both the U and V components indicating that U and V samples are taken for every second pixel across a line. Their vertical subsampling period is 1 indicating that U and V samples are taken on each line of the image.

For YVU9, though, the vertical subsampling interval is 4. This indicates that U and V samples are only taken on every fourth line of the original image. Since the horizontal sampling period is also 4, a single U and a single V sample are taken for each square block of 16 image pixels.

Also, if you are interested in YCrCb to RGB conversion, you may find this page helpful.

Packed YUV Formats

Label FOURCC in Hex Bits per pixel Description
AYUV 0x56555941 32 Combined YUV and alpha
CLJR 0x524A4C43 8 Cirrus Logic format with 4 pixels packed into a u_int32. A form of YUV 4:1:1 wiht less than 8 bits per Y, U and V sample.
CYUV 0x76757963 16 Essentially a copy of UYVY except that the sense of the height is reversed - the image is upside down with respect to the UYVY version.
GREY
(Y800)
0x59455247 8 Apparently a duplicate of Y800 (and also, presumably, "Y8 ")
HDYC
(UYVY)
0x43594448 16 YUV 4:2:2 (Y sample at every pixel, U and V sampled at every second pixel horizontally on each line). A macropixel contains 2 pixels in 1 u_int32. This is a suplicate of UYVY except that the color components use the BT709 color space (as used in HD video).
IRAW 0x57615349 ? Intel uncompressed YUV. I have no information on this format - can you help?
IUYV
(UYVY)
0x56595549 16 Interlaced version of UYVY (line order 0, 2, 4,....,1, 3, 5....) registered by Silviu Brinzei of LEAD Technologies.
IY41 0x31555949 12 Interlaced version of Y41P (line order 0, 2, 4,....,1, 3, 5....) registered by Silviu Brinzei of LEAD Technologies.
IYU1 0x31555949 12 12 bit format used in mode 2 of the IEEE 1394 Digital Camera 1.04 spec. This is equivalent to Y411
IYU2 0x32555949 24 24 bit format used in mode 0 of the IEEE 1394 Digital Camera 1.04 spec
UYNV
(UYVY)
0x564E5955 16 A direct copy of UYVY registered by NVidia to work around problems in some old codecs which did not like hardware which offered more than 2 UYVY surfaces.
UYVP 0x50565955 24? YCbCr 4:2:2 extended precision 10-bits per component in U0Y0V0Y1 order. Registered by Rich Ehlers of Evans & Sutherland.
UYVY 0x59565955 16 YUV 4:2:2 (Y sample at every pixel, U and V sampled at every second pixel horizontally on each line). A macropixel contains 2 pixels in 1 u_int32.
V210 0x30313256 32 10-bit 4:2:2 YCrCb equivalent to the Quicktime format of the same name.
V422 0x32323456 16 I am told that this is an upside down version of UYVY.
V655 0x35353656 16? 16 bit YUV 4:2:2 format registered by Vitec Multimedia. I have no information on the component ordering or packing.
VYUY 0x59555956 ? ATI Packed YUV Data (format unknown)
Y16 0x20363159 16 16-bit uncompressed greyscale image.
Y211 0x31313259 8 Packed YUV format with Y sampled at every second pixel across each line and U and V sampled at every fourth pixel.
Y411 0x31313459 12 YUV 4:1:1 with a packed, 6 byte/4 pixel macroblock structure.
Y41P 0x50313459 12 YUV 4:1:1 (Y sample at every pixel, U and V sampled at every fourth pixel horizontally on each line). A macropixel contains 8 pixels in 3 u_int32s.
Y41T 0x54313459 12 Format as for Y41P but the lsb of each Y component is used to signal pixel transparency .
Y422
(UYVY)
0x32323459 16 Direct copy of UYVY as used by ADS Technologies Pyro WebCam firewire camera.
Y42T 0x54323459 16 Format as for UYVY but the lsb of each Y component is used to signal pixel transparency .
Y8
(Y800)
0x20203859 8 Duplicate of Y800 as far as I can see.
Y800 0x30303859 8 Simple, single Y plane for monochrome images.
YUNV
(YUY2)
0x564E5559 16 A direct copy of YUY2 registered by NVidia to work around problems in some old codecs which did not like hardware which offered more than 2 YUY2 surfaces.
YUVP 0x50565559 24? YCbCr 4:2:2 extended precision 10-bits per component in Y0U0Y1V0 order. Registered by Rich Ehlers of Evans & Sutherland.
YUY2 0x32595559 16 YUV 4:2:2 as for UYVY but with different component ordering within the u_int32 macropixel.
YUYV
(YUY2)
0x56595559 16 Duplicate of YUY2
YVYU 0x55595659 16 YUV 4:2:2 as for UYVY but with different component ordering within the u_int32 macropixel.

Planar YUV Formats

Label FOURCC in Hex Bits per pixel Description
CLPL 0x4C504C43 12 Format similar to YV12 but including a level of indirection.
CXY1 0x31595843 12 Planar YUV 4:1:1 format registered by Conexant.
CXY2 0x32595842 16 Planar YUV 4:2:2 format registered by Conexant.
I420 0x30323449 12 8 bit Y plane followed by 8 bit 2x2 subsampled U and V planes.
IF09 0x39304649 9.5 As YVU9 but an additional 4x4 subsampled plane is appended containing delta information relative to the last frame. (Bpp is reported as 9)
IMC1 0x31434D49 12 As YV12 except the U and V planes each have the same stride as the Y plane
IMC2 0x32434D49 12 Similar to IMC1 except that the U and V lines are interleaved at half stride boundaries
IMC3
(IMC1)
0x33434D49 12 As IMC1 except that U and V are swapped
IMC4
(IMC2)
0x34434D49 12 As IMC2 except that U and V are swapped
IYUV
(I420)
0x56555949 12 Duplicate FOURCC, identical to I420.
NV12 0x3231564E 12 8-bit Y plane followed by an interleaved U/V plane with 2x2 subsampling
NV21 0x3132564E 12 As NV12 with U and V reversed in the interleaved plane
Y41B 0x42313459 12? Weitek format listed as "YUV 4:1:1 planar". I have no other information on this format.
Y42B 0x42323459 16? Weitek format listed as "YUV 4:2:2 planar". I have no other information on this format.
Y8
(Y800)
0x20203859 8 Duplicate of Y800 as far as I can see.
Y800 0x30303859 8 Simple, single Y plane for monochrome images.
YUV9 0x39565559 9? Registered by Intel., this is the format used internally by Indeo video code
YV12 0x32315659 12 8 bit Y plane followed by 8 bit 2x2 subsampled V and U planes.
YV16 0x36315659 16 8 bit Y plane followed by 8 bit 2x1 subsampled V and U planes.
YVU9 0x39555659 9 8 bit Y plane followed by 8 bit 4x4 subsampled V and U planes. Registered by Intel.