A method for image processing includes a graphics processing unit (GPU) of a mobile device obtaining source image data generated by an image sensor of the mobile device and having a source image size and a source color format, the GPU resampling the source image data to generate resampled image data having a target image size suitable to be processed by a central processing unit (CPU) of the mobile device to conduct a target process, and the GPU or the CPU reformatting the resampled image data to generate target image data having a target color format suitable to be processed by the CPU to conduct the target process. The reformatting includes removing at least one color channel for one or more pixels of the resampled image data.