Export BC1 with alpha

Hi i’am trying to export BC1 with alpha but the only option is DXT1a: 1 bit alpha which gives low quality any fix for this ? or can you add export as input file format option ?

Hi @moathraed15! The BC1 compression format specification only supports 1 bit alpha – there’s no such thing as BC1 with more than 1 bit of alpha, unfortunately.

You can check the input file format in the standalone version of the Exporter – if you load an image, you’ll see an “Input Information” pane on the left, like this:

image

If you click on that, it’ll expand to list all the information the Exporter has about the format of the image:

image

If a format other than BC1 is OK, then BC3 or BC7 would probably be best for your use case – BC3 uses a BC1 block for RGB and has a continuous alpha channel; BC7 has better image quality for the same amount of storage space, but since it was released in 2009, apps that use older APIs (e.g. DirectX 9) or older DDS readers might not successfully read BC7 textures.

Hope this helps – let me know if you have any questions!

Perfect thank you

في الاثنين، 8 تموز، 2024 8:47 م Nia Bickford via NVIDIA Developer Forums <notifications@nvidia.discoursemail.com> كتب: