Is BC5 higher quality than DXT5 NM Compression?

Development Programming & Scripting C++
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Is BC5 NM Compression higher quality than DXT5? What are the differences/advantages?

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Interesting question, I don’t know it personnaly but by going on MSDN forums I found that :

BC5 -> Two-channel color	Two color channels (8 bits:8 bits) 	Direct3D 10

this looks interesting too :

https://developer.valvesoftware.com/wiki/DirectX_Texture_compression_5

Edit: from what I’m reading DXT5 should be faster but uses a more agressive form of compression

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Does this mean that BC5 has better quality NM compression?

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It’s should have a better quality normal map compression if I reffer to the text yes.

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DXT5 is just a slightly better version of DXT1+alpha, which is for color maps. BC5 is specifically for normal maps because it compresses the R and G channels independently of each other and discards the B channel to save file size (since the Z can be derived in the pixel shader).

I do not recommend using anything other than BC5 for normal maps as that is the explicit purpose of the format.

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