What is DXT5 format?
DXT5 (BC3) format compresses textures to 8 bits per pixel, and is widely supported on PC and console platforms. It is a good format to compress most of RGBA textures. For RGB (without alpha) textures, DXT1 is better.
How do you compress a sprite in unity?
Try setting Format to Automatic Compressed. For this to work on all mobile platforms make sure the initial image has sizes that are power of 2 (actually I think that multiple of 4 should be enough, but just to be on the safe side). This will lower the quality of the image but should save you some space.
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 compression ratio of the DXT3 format?
But the alpha information is stored with 4 bit in the DXT3 format. That means that in total 128 bit are used for the 16 pixels (32 for the palette, 32 for the colour indices and 64 for the alpha information). So this results in a compression ratio of 1:4.
What is the difference between bc1/dxt1 and DXT1?
The DXT-Formats mostly differ in their handling of the alpha channel (usually used for transparency). Use BC1/DXT1 for pure RGB textures or hard “cut outs” which only need one bit of alpha (fully opaque or fully transparent; note that some tools have a separate mode for this called “DXT1A”)
What is the difference between DXT3 and DXT5?
The DXT5 formats differs from the DXT3 format in the way the alpha information is saved. The colour information is stored in the same way. For the alpha information it uses a palette, similar to the way the colour information is also stored.
What is the data rate for bc3/dxt5 textures?
Use BC3/DXT5 for RGBA textures with smooth interpolated alpha (use this over BC2 unless you’re certain) The data rate is constant regardless of image content: 4 bits per pixel for BC1 and BC4 and 8 bits per pixel for every other format.