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Gary Sullivan coauthored Recommended 8-Bit YUV Formats for Video Rendering by Gary Sullivan and Stephen Estrop with Stephen Estrop. Their technical article connects chroma subsampling, sample storage and conversion between the RGB color model and YCbCr.^[ref]

An original neutral-gray example isolates code range conversion from memory layout. Take eight-bit computer RGB inputs $(R,G,B)=(g,g,g)$, with codes from 0 to 255. Since the three coefficients in the guide's luma combination sum to one, the combined gray value is $g$ regardless of which of its two coefficient sets is selected. For its eight-bit nominal video coding, useThus gray 64 becomes $(Y,U,V)=(71,128,128)$, while gray 192 becomes $(181,128,128)$. The separation of the two stored luma codes is 110 rather than 128. These values follow the stipulated input/output ranges and nearest-integer rounding; copying an RGB component directly into the luma slot would implement a different mapping.^[ref]

Changing a pixel format can rearrange those same codes without performing this conversion. Conversely, converting every pixel's three components does not itself require chroma subsampling. Keeping these operations separate is a practical contribution of the jointly authored guide; no individual authorship of its formulas is inferred.

Stephen Estrop coauthored Microsoft's Recommended 8-Bit YUV Formats for Video Rendering by Gary Sullivan and Stephen Estrop with Gary Sullivan. The article is dated April2002, updated November2008, and specifies sample grids and memory layouts for eight-bit video rendering.^[ref]

An original address calculation illustrates why a pixel format needs more than a sample count. Stipulate an NV12 image of width 10 and height 6, with framebuffer stride 16 bytes in both planes. Let the first luma byte have address 2000, and place the interleaved colour-difference plane immediately after the six stored luma rows. Its base is $2000+6(16)=2096$. The allocation holds $96+48=144$ bytes, although active samples require only $60+30=90$ bytes.

At zero-based row 5, column 9, the luma byte is at $2000+5(16)+9=2089$. Its associated subsampled grid cell is row 2, column 4, whose Cb and Cr bytes are at $2096+2(16)+2(4)=2136$ and 2137. Counting active samples as if they were the allocation size would give the wrong plane base. The shared technical article defines NV12's component order; the chosen dimensions, padding and addresses here are illustrative.^[ref]

These calculations locate stored samples. Reconstructing colour additionally requires chroma sample location, chroma reconstruction and the specified YCbCr conversion. The article's joint byline does not identify which coauthor designed an individual format.