We propose a method for generating standard type linear barcodes from facial images. Our method uses the difference in gradients of image brightness. It involves averaging the gradients into a limited number of intervals, quantization of the results into decimal digits from 0 to 9, and table conversion into the final barcode. The proposed solution is computationally low-cost and does not require the use of any specialized image processing software for generating facial barcodes in mobile systems. Results of tests conducted on the Face94 database show that the proposed method offers a new solution for use in real-world practice. The generated barcodes are stable against changes of scale, pose and mirroring of facial images, as well as changes of facial expressions and shadows on faces from local lighting.