Color Management of JPEG and PNG Images
Important
The modern print platform is Windows' preferred means of communicating with printers. We recommend that you use Microsoft's IPP inbox class driver, along with Print Support Apps (PSA), to customize the print experience in Windows 10 and 11 for printer device development.
For more information, see Modern print platform and the Print support app design guide.
For printers that provide hardware support of JPEG and PNG compressed images, color management must be handled by the driver or device and cannot be handled by GDI.
Before an application sends a JPEG or PNG compressed image to a printer, it will call ExtEscape with either the CHECKJPEGFORMAT or CHECKPNGFORMAT escape code. This results in a call to the driver's DrvQueryDeviceSupport function, with a query type of either QDS_CHECKJPEGFORMAT or QDS_CHECKPNGFORMAT and a buffer containing the compressed image.
The driver can examine the image data and determine if it can support the image. Supporting the image must include performing color transformations if either the XLATEOBJ structure's XO_DEVICE_ICM flag or XO_HOST_ICM flag is set, because GDI cannot perform color transformations on such images.
For these compressed images, color space information is typically contained within the image data. One exception is JFIF files, which are YCbCr-encoded and for which the default sRGB space is a good approximation. However, a JFIF file might contain a proprietary APPx marker that specifies a color space, in which case the driver must transform the image using the color space.
For more information about supporting JPEG and PNG compressed images, see the Remarks section for DEVINFO.