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I extracted KTX textures from an Android game and I tried to convert them using PVRTexToolCLI, however the PNGs do not contain any alpha channel information. Also, some KTX images are not 2 powered size and PVRTexToolCLI does not support them. Is there any solutions for this problem?

Grisha Levit
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C4nf3ng
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1 Answers1

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Are you certain they do contain alpha?

FWIW, using PVRTexToolGUI, I just created a PVRTC 4bpp texture that contained varying alpha in ktx format and then decompressed it using:

PVRTexToolCLI.exe -i SrcFileName.ktx -f r8g8b8a8 -d OutputFileName.png

which worked as expected. I can't comment onthe size question though.

To be honest, you might be better off asking this sort of question on the PowerVR Insider Graphics Forum

Simon F
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    Thank you for your answer I have work out that problem. I found that they stored alpha channel in ktx file bytesOfKeyValueData part https://www.khronos.org/opengles/sdk/tools/KTX/file_format_spec so I convert it to png Using PVRTexToolCLI and write a script to retrieve alpha channel from ktx – C4nf3ng Feb 07 '17 at 17:21
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    Very helpful! Also, for DuckDuckGo visitors, I found PVRTexToolCLI binaries for various platforms in the `bin` folder as part of this open source project: https://github.com/TimvanScherpenzeel/texture-compressor – DWoldrich Mar 10 '20 at 17:35
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    @DWoldrich FWIW binaries should be freely available from the powervr dev site https://www.imgtec.com/developers/powervr-sdk-tools/powervr-sdk/ (link towards the bottom of the page) – Simon F Mar 11 '20 at 09:08