How to know the final vkFormat without transcoding

[tuket]

The ktxTexture2_TranscodeBasis function will change the vkFormat of the image.
I'm wondering if there is any way to know, given a ktxTexture2 and a ktx_transcode_fmt_e, what will be the target vkFormat, without performing the actual transcoding.
I have checked the implementation of ktxTexture2_TranscodeBasis and it does some logic to compute the vkFromat but I wouldn't want to replicate that logic in my application. Is there any way to do this?

[MarkCallow]

Do you need to know in advance programmatically? If so, why?

The format comes directly from the ktx_transcode_fmt_e you specify. For example

KTX_TTF_BC3_RGBA is equivalent to VK_FORMAT_BC3_{UNORM,SRGB}_BLOCK. Whether it is UNORM or SRGB is decided by the image data as indicated by the return value of ktxTexture2_GetTransferFunction_e. If it is KHR_DF_TRANSFER_SRGB the result will be SRGB otherwise it will be UNORM.

Similarly KTX_TTF_ASTC_4x4_RGBA means transcode to VK_FORMAT_ASTC_4x4_{UNORM,SRGB}_BLOCK.

[tuket]

Thanks for your answer.
I need to know in advance because of the architecture of the engine I develop at work. Importers have two callbacks "ImportHeader" and "ImportData". In ImportHeader I need to return things like the dimensions and format of the texture.