In these two planar formats, all Y samples appear first in memory as an array of WORDs with an even number of lines. 4:2:2 Formatsįour 4:2:2 formats are defined, two planar and two packed. They are expected to be an intermediate-term requirement for DirectX Video Acceleration (DXVA) accelerators that support 10-bit or 16-bit 4:2:0 video. These two formats are the preferred 4:2:0 planar pixel formats for higher precision YUV representations. The U-V plane has half as many lines as the Y plane. The stride of the combined U-V plane is equal to the stride of the Y plane. If the combined U-V array is addressed as an array of DWORDs, the least significant word (LSW) contains the U value and the most significant word (MSW) contains the V value. This array is followed immediately by an array of WORDs that contains interleaved U and V samples, as shown in the following diagram. The surface stride can be larger than the width of the Y plane. In these two formats, all Y samples appear first in memory as an array of WORDs with an even number of lines. They share the same memory layout, but P016 uses 16 bits per channel and P010 uses 10 bits per channel. Two 4:2:0 formats are defined, with the FOURCC codes P016 and P010.
In the descriptions that follow, the term WORD refers to a little-endian 16-bit value, and the term DWORD refers to a little-endian 32-bit value. This section describes the memory layout of each format. Subtype GUIDs have also been defined from these FOURCCs see Video Subtype GUIDs. No 4:2:1 formats for 10-bit or 16-bit YUV have been defined at this time. Using this scheme, the following FOURCC codes have been defined. The final two characters in the FOURCC indicate the number of bits per channel, either '16' for 16 bits or '10' for 10 bits.
#Yuv player windows 10 code#
The second character in the FOURCC code is determined by the chroma sampling, as shown in the following table. If the format is packed, the first character is 'Y'. If the format is planar, the first character in the FOURCC code is 'P'. The FOURCC codes for the formats described here use the following convention: The origin (0,0) is always the upper-left corner of the surface.įor the purposes of this documentation, the term U is equivalent to Cb, and the term V is equivalent to Cr. That is, individual lines within a surface are guaranteed to start at a 32-bit boundary, although the alignment can be larger than 32 bits.
#Yuv player windows 10 driver#
Alpha is assumed to be a linear value that is applied to each component after the component has been converted into its normalized linear form.įor images in video memory, the graphics driver selects the memory alignment of the surface. In the formats that contain alpha, a completely transparent pixel has an alpha value of zero, and a completely opaque pixel has an alpha value of (2^n) – 1, where n is the number of alpha bits. If a surface contains valid 16-bit data, however, it should be identified as a 16-bit surface. When the graphics hardware reads a surface that contains a 10-bit representation, it should ignore the low-order 6 bits of each channel. (The Y416 and Y410 formats are an exception to this general rule, however, because they do not share the same memory layout.) It is also possible to cast a 16-bit representation down to a 10-bit representation. The 10-bit formats also use 16 bits for each channel, with the lowest 6 bits set to zero, as shown in the following diagram.īecause the 10-bit and 16-bit representations of the same YUV format have the same memory layout, it is possible to cast a 10-bit representation to a 16-representation with no loss of precision. The 16-bit representations described here use little-endian WORD values for each channel. For example, if the white point of an 8-bit format is 235, the corresponding 10-bit format has a white point at 940 (235 × 4). Precision conversions can be performed using simple bit shifts.
Sample values are scaled 8-bit values, using a scaling factor of 2^(n − 8), where n is either 10 or 16, as per sections 7.7-7.8 and 7.11-7.12 of SMPTE 274M. These formats use a fixed-point representation for both the luma channel and the chroma (C'b and C'r) channels. This topic contains the following sections: This topic describes the 10- and 16-bit YUV formats that are recommended for capturing, processing, and displaying video in the Microsoft Windows operating system.
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