基于模式噪声的数字图像来源鉴别

利用相关性原理,提出一种鉴别数字图像来源的新方法.由于成像传感器的非理想性,每一种数码相机都会输出一种相对稳定的残留噪声,用小波滤波器从数字图像中提取这一噪声,利用多幅图像的噪声取平均值的办法建立噪声参考模式,求出待鉴别数字图像的噪声与噪声参考模式间的相关系数,把这一相关系数与预设的阈值进行比较,判定数字图像来源于哪一种相机.通过实验验证了该方法的可靠性,并应用最小错误率Bayes决策规则求出各种相机的判别阈值.

Identification of Digital Image Origin Based on the Pattern Noise

A novel method is proposed to identify digital image origin with the correlation theory. Digital images form digital cameras contain relatively stable residual noise due to the imperfection of imaging of imaging sensors. After deriving residual noise from an image through wavelet filtering,a reference pattern of noise for a digital camera is extracted by averaging the residual noise from multiple images. By comparing the correlation between the residual noise of the image to be evaluated and the reference pattern with a predetermined threshold,the origin of the image can be determined through. Bayesian decision theory with minimum-error-rate is used to derive the threshold. Experiment results show the effectiveness of the proposed method.