Secret image sharing approaches have been extended to obtain covers from stego images after the revealing procedure. Lin et al.’s work in 2009 uses modulus operator to decrease the share image distortion while providing recovery of original covers. Their work use gray level or binary image as cover. Stego images have approximately 43 dB and 38 dB PSNR for gray level and binary covers respective...

The purpose of this work is to associate the channel encoder called ‘trellis-coded modulation with Ungerboeck-Gray mapping’ (TCM-UGM) to ‘space-time block code’ (STBC), in order to study its performance to correct the transmission errors of a JPEG image. The performance of the proposed scheme is evaluated in senses of bit error rate (BER), frame error rate (FER) and peak signal-to-noise ratio (...

By employing nonuniform nonunitary lter bank in an image coder increased performance in terms of both theoretical and practical (PSNR) coding gains, and subjective quality can be obtained. One possible candidate is octave-band tree-structured lter banks. In this paper, an optimized perfect reconstruction octave-band three-stage tree-structured lter bank is proposed. The lter coeecients are opti...

In this paper, vector quantizer optimization is accomplished by a hybrid evolutionary method, which consists of a modified genetic algorithm (GA) with a local optimization module given by an accelerated version of the K-means algorithm. Simulation results regarding image compression based on VQ show that the codebooks optimized by the proposed method lead to reconstructed images with higher pea...

In this paper, we show that it is possible to reduce the complexity of Intra MB coding in H.264/AVC based on a novel chance constrained classifier. Using the pairs of simple mean-variances values, our technique is able to reduce the complexity of Intra MB coding process with a negligible loss in PSNR. We present an alternate approach to address the classification problem which is equivalent to ...

Wavelet transformation is one of the most popular time-frequency-transformations. It is powerful feature for the signals and frequency analysis of an image. Image compression is key technology for transmission and storage of digital images. In this paper the compression algorithms are applied on various biomedical images. The algorithms used in this paper are SPIHT and EZW for comparing the qua...

This paper introduces an image denoising algorithm based on generalized Srivastava-Owa fractional differential operator for removing Gaussian noise in digital images. The structures of n n× fractional masks are constructed by this algorithm. Experiments show that, the capability of the denoising algorithm by fractional differential-based approach appears efficient to smooth the Gaussian noisy i...

We have implemented super-resolution techniques such as machine learning methods and solving a least squares problem with a prior to perform demosaicing. These techniques include k-nearest neighbors (KNN), linear regression, and alternating direction method of multipliers with a total variation prior (ADMM TV). For all methods, parameters were optimized to minimize the mean-squared-error (MSE) ...

A new image denoising method based on curvelet transform is proposed. The limitations of commonly used separable extensions of one-dimensional transforms, such as the Fourier and wavelet transforms, in capturing the geometry of image edges are well known. Here, we pursue "true" two-dimensional transform that can capture the intrinsic geometrical structure that is key in visual information. Deno...

Blocking artifact is one of the most annoying artifacts in video and image compression coding. In order to improve the quality of the reconstructed image and video, several deblocking algorithms have been proposed. In this paper, we will introduce these deblocking algorithms and classify them into several categories. On the other hand, the conventional PSNR is widely adopted for estimating the ...