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What format is BC7?
texture compression format
The BC7 format is a texture compression format used for high-quality compression of RGB and RGBA data. For info about the block modes of the BC7 format, see BC7 Format Mode Reference.
What is BC1 compression?
DXT1 (also known as Block Compression 1 or BC1) is the smallest variation of S3TC, storing 16 input pixels in 64 bits of output, consisting of two 16-bit RGB 5:6:5 color values and. , and a 4×4 two-bit lookup table.
What is BC5?
BC5. Use the BC5 format to store two-component color data using 8 bits for each color. The algorithm uses the 3-bit indices to look up colors from a color table that contains 8 colors.
What’s a DDS file?
A DDS file is a binary file that contains the following information: A DWORD (magic number) containing the four character code value ‘DDS ‘ (0x20534444). A description of the data in the file. The data is described with a header description using DDS_HEADER; the pixel format is defined using DDS_PIXELFORMAT.
What do you need to know about Bc7 format?
The BC7 format is a texture compression format used for high-quality compression of RGB and RGBA data. For info about the block modes of the BC7 format, see BC7 Format Mode Reference. BC7 is specified by the following DXGI_FORMAT enumeration values:
Are there different ways to compress Bc7 textures?
Update: According to quick look at the DirectCompute example HLSL code that compresses BC7 there seems to be 8 different modes to compress a block, and 64 different color partitioning styles. It’s still a mystery for me how the alpha channel is handled, and how the second palette is stored…
How big is the block size in Bc7?
BC7 uses a fixed block size of 16 bytes (128 bits) and a fixed tile size of 4×4 texels. As with previous BC formats, texture images larger than the supported tile size (4×4) are compressed by using multiple blocks. This addressing identity also applies to three-dimensional images and MIP-maps, cubemaps, and texture arrays.
When does the BC7 decoder perform texture filtering?
The BC7 decoder performs decompression before texture filtering is applied. BC7 decompression hardware must be bit accurate; that is, the hardware must return results that are identical to the results returned by the decoder described in this document.