Abstract: The invention provides, in some aspects, methods for image compression that utilize the central processing unit (CPU) of a digital data processor and its associated graphics processing unit (GPU), together, in order to compress an image. In related aspects of the invention, the GPU is adapted to render at least a portion of an image to an associated texture buffer (i.e., a texture buffer of the GPU) and to transform the resulting image values in that texture buffer to a frequency-based representation. The GPU can, further, order coefficients comprising that frequency-based representation and transfer at least a portion of those coefficients to the associated CPU. That CPU can, in turn, effect transfer of the downloaded coefficients to another digital data processor (or image processing apparatus).