An image passthrough extension structure and method facilitating the transfer of compressed data image files from a software application to a device via the computer system operating system. The application determines whether the device is capable of decoding the specific compressed data file by polling the device driver. If the driver returns a "no support" message, the application processes the compressed data file in a conventional manner. If the driver returns a "support" message, the application transfers the compressed data file, along with the additional processing information, to the device driver utilizing the conventional file transfer operating system data structures modified to incorporate the compressed data file passthrough function. By allowing an application to transfer a compressed image file directly to a device driver, the present invention improves image fidelity and improves overall computer system efficiency by reducing the size of data files transferred between the application, the operating system and the hardware device.