Optimizing Image Preparation and Compression for Face Recognition within 1024 Bytes
2026-06-29 • Computer Vision and Pattern Recognition
Computer Vision and Pattern Recognition
AI summaryⓘ
The authors studied how to store face images on small 2D barcodes for temporary travel documents, which need much smaller file sizes than usual RFID chips. They tested different image compression methods like JPEG AI, AVIF, and WebP to keep the pictures recognizable for automatic face verification, even when compressed down to about 1024 bytes. Their results showed that JPEG AI worked best, especially with good quality images. They also found that converting images to black and white helps in some cases, while keeping color is better in others. Preprocessing steps like smoothing and resizing also improved recognition.
ICAOmachine readable travel documentsbiometric face verificationRFID2D barcodeimage compressionJPEG AIAVIFface recognitionpreprocessing
Authors
Paul Andreas, Torsten Schlett, Christoph Busch
Abstract
ICAO-compliant machine readable travel documents enable automated biometric face verification. The biometric reference is stored on an RFID chip included in form of a JPEG or JPEG 2000 compressed facial image. In contrast, temporary travel documents lack of machine readability, which excludes the owner from such automated processes. This disadvantage could be solved by equipping such documents with 2D barcodes. This technology offers a resource-saving alternative to expensive RFID chips, while still offering machine readability and fast issuing processes. However, this solution introduces the challenge of storing the face images at significantly smaller storage capacities, creating the need for reducing the file size of the included facial image to a maximum of 1024 bytes. This study examines preprocessing steps and compression configurations, using JPEG, JPEG 2000, JPEG XL, JPEG AI, HEIF, AVIF, and WebP for image compression to this target size, while still preserving as much face recognition performance as possible. While the reference sample must always comply with ICAO specifications, the individual samples may or may not meet these requirements, depending on the application. This work optimizes compression steps for both of these prerequisites. It is shown that the recently standardised JPEG AI, when using optimized settings, provides the best face recognition performance, in particular when the comparison includes only images with high face image quality. AVIF and WebP also provide good results. The losses caused by the strong lossy compression are comparatively small. For the comparison of ICAO-compliant face images only, converting the images to grayscale proves to be a helpful preprocessing step, whereas for comparisons involving less suitable samples, preserving color is preferable. In addition, smoothing and resizing the images beforehand also turns out to be beneficial.