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Detection of visually salient image regions is useful for applications like object segmentation, adaptive compression , and object recognition. In this paper, we introduce a method for salient region detection that outputs full resolution saliency maps with well-defined boundaries of salient objects. These boundaries are preserved by retaining substantially(More)
This paper presents an efficient metric for quantifying the visual fidelity of natural images based on near-threshold and suprathreshold properties of human vision. The proposed metric, the visual signal-to-noise ratio (VSNR), operates via a two-stage approach. In the first stage, contrast thresholds for detection of distortions in the presence of natural(More)
Assumptions about image continuity lead to oversmoothed edges in common image interpolation algorithms. A wavelet-based interpolation method that imposes no continuity constraints is introduced. The algorithm estimates the regularity of edges by measuring the decay of wavelet transform coefficients across scales and preserves the underlying regularity by(More)
Transmission of still images and video over lossy packet networks presents a reconstruction problem at the decoder. Specifically, in the case of block-based transform coded images, loss of one or more packets due to network congestion or transmission errors can result in errant or entirely lost blocks in the decoded image. This article proposes a(More)
Recently, image compression systems based on the Tarp filter have attracted much attention in the image processing community. While providing very good performance when used in a non-embedded manner, the original Tarp-filter-based algorithm performs less competitively when used in an embedded manner (in spite of its operation on bitplanes), because of its(More)
The structural similarity (SSIM) metric and its multi-scale extension (MS-SSIM) evaluate visual quality with a modied local measure of spatial correlation consisting of three components: mean, variance, and cross-correlation. This paper investigates how the SSIM components contribute to its quality evaluation of common image artifacts. The predictive(More)
The additivity of wavelet subband quantization distortions was investigated in an unmasked detection task and in masked detection and discrimination tasks. Contrast thresholds were measured for both simple targets (artifacts induced by uniform quantization of individual discrete wavelet transform subbands) and compound targets (artifacts induced by uniform(More)
—This paper introduces a new high-rate analysis of the multiple description scalar quantizer (MDSQ) with balanced descriptions. The analysis provides insight into the structure of the MDSQ, suggesting the nonoptimality of uniform central quantizer cell lengths, as well as a method to approximate optimal cell lengths. For both level-constrained and(More)
Present quality assessment (QA) algorithms aim to generate scores for natural images consistent with subjective scores for the quality assessment task. For the quality assessment task, human observers evaluate a natural image based on its perceptual resemblance to a reference. Natural images communicate useful information to humans, and this paper(More)