We present a practical match-on-card design for face verification in which compact 64/128-bit templates are produced off-card by PCA-ITQ and compared on-card via constant-time Hamming distance. We specify ISO/IEC 7816-4 and 14443-4 command APDUs with fixed-length payloads and decision-only status words (no score leakage), together with a minimal per-identity EEPROM map. Using real binary codes from a CelebA working set (55 identities, 412 images), we (i) derive operating thresholds from ROC/DET, (ii) replay enroll->verify transactions at those thresholds, and (iii) bound end-to-end time by pure link latency plus a small constant on-card budget. Even at the slowest contact rate (9.6 kbps), total verification time is 43.9 ms (64 b) and 52.3 ms (128 b); at 38.4 kbps both are <14 ms. At FAR = 1%, both code lengths reach TPR = 0.836, while 128 b lowers EER relative to 64 b. An optional +6 B helper (targeted symbol-level parity over empirically unstable bits) is latency-negligible. Overall, short binary templates, fixed-payload decision-only APDUs, and constant-time matching satisfy ISO/IEC transport constraints with wide timing margin and align with ISO/IEC 24745 privacy goals. Limitations: single-dataset evaluation and design-level (pre-hardware) timing; we outline AgeDB/CFP-FP and on-card microbenchmarks as next steps.
翻译:我们提出了一种实用的人脸验证卡内比对设计方案,其中紧凑的64/128位模板由卡外PCA-ITQ算法生成,并通过恒定时间的汉明距离在卡内进行比对。我们规定了具有固定长度载荷和仅含决策状态字(无分数泄露)的ISO/IEC 7816-4与14443-4命令APDU,以及一个最小的每身份EEPROM映射。使用来自CelebA工作集(55个身份,412张图像)的真实二进制编码,我们(i)从ROC/DET曲线推导出操作阈值,(ii)在这些阈值下重放注册->验证事务,以及(iii)通过纯链路延迟加上卡内少量恒定开销来限定端到端时间。即使在最慢的接触式速率(9.6 kbps)下,总验证时间分别为43.9毫秒(64位)和52.3毫秒(128位);在38.4 kbps速率下,两者均小于14毫秒。在FAR = 1%时,两种编码长度均达到TPR = 0.836,而128位编码相对于64位编码降低了EER。一个可选的+6字节辅助数据(针对经验上不稳定比特的符号级奇偶校验)对延迟影响可忽略。总体而言,短二进制模板、固定载荷仅决策APDU和恒定时间比对满足了ISO/IEC传输约束,具有宽裕的时间余量,并符合ISO/IEC 24745的隐私保护目标。局限性:单数据集评估和设计层面(硬件前)的时序分析;我们概述了AgeDB/CFP-FP数据集评估和卡内微基准测试作为下一步工作。