Binary Texture Fetches

I’m doing some morphological operations such as erosion and dilation on images. Since the outcome of such operations are binary, I only need one bit per pixel to store the results. Therefore, I’m able to pack the results of 8 pixels into a single byte in a pitched linear memory buffer. I now would like to further use this compact representation of my results as input for other binary image operations. Is there a way to use textures which fetch single bits (or generally, less than 8 bits)?

No, the smallest texture format is 1 x 8 bits, I believe.

DX10 used to have a 1-bit texture format (intended for text), but nobody used it.