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Visual quality of color images is an important aspect in various applications of digital image processing and multimedia. A large number of visual quality metrics (indices) has been proposed recently. In order to assess their reliability, several databases of color images with various sets of distortions have been exploited. Here we present a new database(More)
In this paper we propose a simple and effective model of visual between-coefficient contrast masking of DCT basis functions based on a human visual system (HVS). The model operates with the values of DCT coefficients of 8x8 pixel block of an image. For each DCT coefficient of the block the model allows to calculate its maximal distortion that is not visible(More)
In this paper, two new full-reference metrics for image quality assessment are presented. They are based on the Peak-Signal-to-Noise Ratio (PSNR) and Universal Quality Index (UQI) modified to take into account the Human Visual System (HVS) properties. Many studies confirm that the HVS is more sensitive to low frequency distortions rather than to high(More)
This paper describes a recently created image database, TID2013, intended for evaluation of full-reference visual quality assessment metrics. With respect to TID2008, the new database contains a larger number (3000) of test images obtained from 25 reference images, 24 types of distortions for each reference image, and 5 levels for each type of distortion.(More)
In this contribution, a new image database for testing full-reference image quality assessment metrics is presented. It is based on 1700 test images (25 reference images, 17 types of distortions for each reference image, 4 levels for each type of distortion). Using this image database, 654 observers from three different countries (Finland, Italy, and(More)
Graphical information as color images is widely used in CAD and telecommunication systems. Several factors can contribute to impair the quality of an image. This paper deals with image visual quality assessment using objective metrics. Experimental results show that the two modified quality metrics outperform existing ones for a wide set of possible(More)
This paper presents a novel method to blindly estimate the quality of a multimedia communication link by means of an unconventional use of digital fragile watermarking. Data hiding by digital watermarking is usually employed for multimedia copyright protection, authenticity verification, or similar purposes. However, watermarking is here adopted as a(More)
A robust error concealment scheme using data hiding which aims at achieving high perceptual quality of images and video at the end-user despite channel losses is proposed. The scheme involves embedding a low-resolution version of each image or video frame into itself using spread-spectrum watermarking, extracting the embedded watermark from the received(More)
In this paper, a new no-reference (NR) objective metric based on data hiding is proposed. The metric has the advantage of being fast and not requiring knowledge of the original video contents. The proposed method uses a spreadspectrum embedding algorithm to embed a mark (binary image) into video frames. At the receiver, the mark is extracted and a measure(More)