Data security has become an important problem in the communication systems. Steganography is used to hide existence of a secret-message. In this article a modified Steganography algorithm will be proposed depending on decomposition principle of both secret-message and cover-image. A fuzzification is performed in the secret message to optimize the decomposed coefficients before embedding in the coverimage to get a Stego Image. The well known metrics (Cor., MSE, PSNR, and Entropy) were used to evaluate the modified algorithm. Also, a trade-off factor was introduced to determine an optimum value for the embedding strength factor to get an acceptable degradation. Moreover to evaluate and assess the modified algorithm and any Steganography algorithms, a new histogram metrics are proposed which represents the relative frequency occurrence of the various images.