… Convert an Image to KTX Using Basis Universal Supercompression#
Gestaltor supports converting images to specify textures using KTX images with Basis Universal supercompression.
Open a glTF File > Open… in the menu bar. e.g. Corset
In the Content widget, select the first entry in the images section.
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In the Inspector widget, press Convert image and choose ktx2 as the format.
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Choose the compression of choice and press Apply. Depending on the image, this can take some time.
Gestaltor automatically enables the KHR_texture_basisu extension in glTF.