改进同态图像秘密共享ElGamal ECC加密体制

Improved elliptical curve ElGamal based homomorphic image encryption scheme for sharing secret images

针对Li等人提出的ElGamal椭圆加密体制进行改进,该方案不需要增加计算开销就能提高接收者验证图像正确性的能力。一旦接收者发现加密图像的某些块被污染或者窜改,可立即丢掉这个图像,不需要等到整个图像完全解密出来后才判断出此图像已损坏。结果表明本方案能够对图像快速处理,提高验证速度,减少计算开销。

This communication improved Li et al. ＇s scheme based on homomorphic image encryption scheme for sharing secret images. This schemeenhances the capability of the receiverto verify the correctness of the encrypted imageswithout sacrificing the computation overhead. Once some encrypted image block（s） of the encrypted image was distinguished to be garbled （dirty）, the receiver could reject the image directly rather than asserting the garbage only after decrypting the whole image. The result shows that this scheme can process the image rapidly, reduce the calculatin~ overhead and improve the speed of verification.