# Optimal settings **URL:** \ **Category:** KTX\ **Created:** [March 24, 2022, 12:33pm UTC](https://community.khronos.org/t/optimal-settings/108434 "2022-03-24T12:33:54Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![ShaderRig](https://community.khronos.org/letter_avatar_proxy/v4/letter/s/ccd318/32.png) [@ShaderRig](https://community.khronos.org/u/ShaderRig)\ **Post date:** [March 24, 2022, 12:33pm UTC](https://community.khronos.org/t/optimal-settings/108434/1 "2022-03-24T12:33:54Z")
Optimal settings Hi, I’ve recently started looking into KTX2.0 and would love some feedback about optimal settings. I’m converting 3 different textures for my project, Albedo, Normal and a packed texture which includes AO, roughness and metallic. The file size output I’m getting seems high to me, for the packed texture compared to .astc compression. Here is what I’m using to convert my image files (PNG): Albedo: toktx -bcmp -qlevel 255 -clevel 5 --lower\_left\_maps\_to\_s0t0 Normal: toktx --assign\_oetf linear -normalmap --uastc 15 --uastc\_rdo\_l [.25,.75] --zcmp 15 --lower\_left\_maps\_to\_s0t0 Packed texture: toktx --assign\_oetf linear --uastc 15 --uastc\_rdo\_l [.25,10] --zcmp 15 --lower\_left\_maps\_to\_s0t0 My results: TestImage01.png 1024 x 1024 PNG: 1.03 mb KTX2: 743 kb ASTC: 257 kb TestImage02.png 2048 x 2048 PNG: 2.18 mb KTX2: 1.82 mb ASTC: 1.025 How can I optimise these settings while retaining visual quality? Thank you for your time. ---
**Author:** ![Alfonse\_Reinheart](https://community.khronos.org/user_avatar/community.khronos.org/alfonse_reinheart/32/4357_2.png) [@Alfonse\_Reinheart](https://community.khronos.org/u/Alfonse_Reinheart)\ **Post date:** [March 24, 2022, 1:36pm UTC](https://community.khronos.org/t/optimal-settings/108434/2 "2022-03-24T13:36:36Z")
What is the difference between your KTX2 and ASTC versions? KTX2 is a file format that can store images in a number of different formats, _including_ any of the ASTC compressed formats. So what image format are you using in the KTX2 version that’s different from the ASTC version? Also, which ASTC formats are you using? How many channels are in each image?