What is DXT compression?

What is DXT compression?

DXT1 compression is a form of Block Truncation Coding (BTC) [3] where an image is divided into non- overlapping blocks, and the pixels in each block are quantized to a limited number of values. The color values of pixels in a 4×4 pixel block are approximated with equidistant points on a line through RGB color space.

What is textured game compression?

Texture compression is a form of lossy image compression that allows the GPU to render directly from the compressed texture using specialized silicon blocks, reducing the texture memory and memory bandwidth required to render the texture.

How do I compress a texture in unity?

If you enable the “Use Crunch Compression” option in the Default tab, all the textures on Android platform will be compressed with ETC Crunch by default….Compressing textures with Crunch using DXT encoding.

Unity 2017.2.0f3 Unity 2017.3.0b5
Compressed size 156.3 MB 138.1 MB
Compression time 45.1 minutes 19.5 minutes

Which is better ASTC or etc?

Then you should use the ASTC format which has better quality and is more efficient than the other formats….Hardware Accelerated Formats.

ETC1 Supported on all Android devices with OpenGL ES 2.0 and above. Does not support alpha channel.
ASTC Higher quality than ETC1 and ETC2. Supported with the Android Extension Pack.

What is DXT5 compression?

DXT5 format compresses textures to 8 bits per pixel, and is widely supported on PC, console and Windows Phone platforms. It is a good format to compress most of RGBA textures. For RGB (without alpha) textures, DXT1 is better.

What is DXT5 format?

The DXT5 format is an alternate RGBA format. As in the DXT3 case, each 4×4 block takes up 128 bits. So it provides the same 4:1 compression as in the DXT3 case. You can get this with the GL_COMPRESSED_RGBA_S3TC_DXT5_EXT format.

Does texture compression improve performance?

There is a performance gain when working with compressed textures because there is not as much data that needs to be sent down the pipeline.

Do compressed textures look worse?

All GPU texture compressions are lossy. There is a slight degradation in image quality that may or may not be noticeable depending on what is in the texture.

What is ETC2 fallback in unity?

ETC2 fallback This option allows you to choose between the uncompressed image quality and the amount of memory the uncompressed texture occupies.

How do I change the compression in unity?

Unity texture import settings can be adjusted by selecting the texture in the project window to show the texture import settings in the inspector window. From the texture import settings you can set texture compression, control mip-mapping and adjust few other useful texture settings.

How does ASTC compression work?

The standard solution that all contemporary real-time formats use, including ASTC, is to divide the image into fixed-size blocks of texels. Each block is then compressed into a fixed number of output bits. This feature makes it possible to access texels quickly, in any order, and with a well-bounded decompression cost.

What is DXT1?

A DXT1-compressed image is an RGB image format. As such, the alpha of any color is assumed to be 1. Each 4×4 block takes up 64-bits of data, so compared to a 24-bit RGB format, it provides 6:1 compression. You can get a DXT1 image by using the GL_COMPRESSED_RGB_S3TC_DXT1_EXT as the internal format of the image.

What is the difference between S3TC and etc texture formats?

These formats are firmly rooted in desktop GPUs. They are basically non-existent on mobile GPUs. The ETC family of formats is very similarly laid out to S3TC in how different texture types are supported, but the implementation detail is quite different (and ETC2 is quite the interesting format).

Where can I download ETC2 textures for free?

A software utility called etcpack for compression and decompression of ETC1/ETC2 textures is available for free download in code form from Ericsson on GitHub. The ‘Smooth Profile’ is on the paper only.

What is the etc compression format?

With the introduction of OpenGL ES 2.0, the ETC compression format became an available multi-vendor extension, offering DXT-like compression at better quality levels. However, it had issues that hampered its widespread adoption: it was not a required piece of ES 2.0, there was no alpha support, and it had only one mode, 4bpp RGB.

What is DXT (S3TC)?

In the modern desktop computing age, there has classically been one answer to texture compression: DXT. It is also referred to as S3TC due to its origin, or BCn for certain DirectX implementations. At its most basic, it is a fixed 4×4 block format that uses 4bpp to encode each RGB block.