This format is the most popular YUV420 format. They comprise an NxN Y plane followed by (N/2)x(N/2) U and V planes. Full marks to Intel for registering the same format twice and full marks to Microsoft for not picking up on this and rejecting the second registration.
Horizontal Vertical Y Sample Period 1 1 U Sample Period 2 2 V Sample Period 2 2
Positive biHeight implies top-down image (top line first)
YUV 4:2:0 image with a plane of 8 bit Y samples followed by an interleaved U/V plane containing 8 bit 2x2 subsampled colour difference samples. It is called as XDM_YUV_420SP by TI XDM.
|Y Sample Period||1||1|
|V (Cr) Sample Period||2||2|
|U (Cb) Sample Period||2||2|
Microsoft defines this format as follows:
"A format in which all Y samples are found first in memory as an array of unsigned char with an even number of lines (possibly with a larger stride for memory alignment), followed immediately by an array of unsigned char containing interleaved Cb and Cr samples (such that if addressed as a little-endian WORD type, Cb would be in the LSBs and Cr would be in the MSBs) with the same total stride as the Y samples. This is the preferred 4:2:0 pixel format."
For conversion from yuv420 IYUV/I420 to yuv420 NV12 to make NV12 test clip, ffmpeg can be used as a IYUV2NV12 converter: