2D Bit Rates. 3D Bit Rates. 4×4 bpp 10×5 bpp 3x3x3 bpp 5x5x4 bpp. 5×4 bpp 10×6 bpp 4x3x3 bpp 5x5x5 bpp. 5×5 . Adaptive Scalable Texture Compression (ASTC) technology developed by Arm and AMD has been adopted as an official extension to both the OpenGLĀ® and. Adaptative Scalable Texture Compression (ASTC) is a new texture com- pression format which is set to take the world by storm. Having been accepted as a new.

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Unity splits the resulting atlas into two Textures, each without an alpha channel, and then combines them in the final parts of the render pipeline. OpenGL 4, Linux Note: What is meant by “correlated” is that the two channels will be tied to the same gradient.

Unity – Manual: Texture compression formats for platform-specific overrides

To avoid the myriad vendor-specific codecs, Khronos defined vendor-neutral codecs. This allows content developers to fine-tune the tradeoff of space against quality.

The table below shows supported platforms for each compression format. The method of compression is an evolution of Color Cell Compression with features including numerous closely spaced fractional bit rates, multiple color formats, support for High Dynamic Range HDR textures, and real 3D texture support. But before you shrink the resolution of your textures, consider modern device screens. It is designed to compresson easy to integrate with existing hardware designs that already deal with compressed 2D images in other formats.


So the 4×4 version of ASTC, the smallest block size, takes up 8 bits per pixel, while the 12×12 version takes coompression only 0. The byte sizes can be different based on different variations of the format.

ASTC Texture Compression – OpenGL Wiki

aetc So even if you compress an image with one channel in every block, you use the same OpenGL image format you would if you had compressed an image with full RGBA channels. When this happens, time is lost decompressing Textures, and memory is lost because you texturee storing them twice. This delivers better image quality than previous formats, even at higher compression. At its most basic, it is a fixed 4×4 block format that uses 4bpp to encode each RGB block.

More recently Imagination has released the PVRTC2 formats, which offer better compression quality in the same footprint.

This is quite useful for improving compression quality. ASTC specification includes two profiles: The available bit rates thus range from 8 bits per texel down to 0. Then, in the shader, multiplying the result sampled from the texture by 2 and subtracting 1 to reconstitute the signed value. If you have a texture that uses alpha to cut a hole in the middle, the parts outside of this will have a constant alpha of one.

Adaptive Scalable Texture Compression (ASTC)

Most compression formats have a fixed size of blocks. See Notes above for more on crunch compression. Views Read Edit View history. While Unity supports many common image formats as source files for importing your Textures An image used when rendering a GameObject, Sprite, or UI element.


It is well known for its use on iOS devices for texture compression. This site uses cookies to store information on your computer.

ASTC does allow for flexible block sizes, but not within an image; the entire image must be compressed with the same block compression. Sometimes that is accomplished with compresssion RAM but more often it is achieved with native support for compressed texture formats.

Texture compression formats for platform-specific overrides

And sRGB colorspace conversion is something that happens after decompression. Please tell us more about what you found unclear or confusing, or let us know how we could make it clearer: By default, the main camera in Unity renders its view to the screen. You’ve told us this page has unclear or confusing information. Example Compression Testing To better discuss the effects of different codecs on content, we performed a batch compression run against a small set of textures and assigned a visual image quality IQ rating to each.

They are able to be used with all other textures, compreszion 1D Array Textures.

Pixel size depends on your screen resolution. That said, you may find content which “tolerates” highest compression well, or decide that smaller size is more important than the resulting artifacts. The result was compelling: