YV12

YV12 is a planar video pixel format used to store color frames. It represents luma (Y) and chrominance components (V and U) separately with 4:2:0 chroma subsampling. In YV12, the Y plane contains width × height samples of luma at full resolution. The chroma planes V and U each contain (width/2) × (height/2) samples. The data is stored as three separate planes in memory: first the Y plane, then the V plane, and finally the U plane. This ordering (Y, V, U) distinguishes YV12 from I420, which stores the chroma planes in the order U then V.

Because of 4:2:0 subsampling, chroma resolution is reduced by a factor of 2 in both horizontal and vertical directions; total bytes per frame equal width × height plus half of that for chroma planes (1.5 × width × height).

YV12 is widely used as a raw video pixel format in software libraries and codecs, including FFmpeg/Libav, where it is represented as AV_PIX_FMT_YV12 or PIX_FMT_YV12. It is a planar format, as opposed to packed formats like YUYV or semi-planar like NV12, where chroma is interleaved.

Applications include video decoding and processing pipelines for formats such as MPEG-2, MPEG-4 part2, and H.264 in 4:2:0, typically when uncompressed frames are needed for processing. YV12 is common for 8-bit depth; variants exist for other bit depths, though they may use different names.