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In this paper we make contributions to a non-blind multiple watermarking scheme that proceeds by embedding a binary image in the discrete wavelet transform bands of a gray scale image. Unlike the common wavelet based watermarking techniques, the proposed scheme lies essentially on marking the approximation and diagonal bands of the discrete wavelet transform (DWT) of the cover image achieving a better...
Error concealment (EC) is an efficient way to improve video quality against transmission errors because compressed video bit streams are extremely sensitive to packet loss over error-prone channels. Once packet loss occurs, the decoder may not reconstruct the video image well, and even fail to decode the bit streams if important data are missing. We study the problem of recovering pixels of lost macroblocks...
Medical images play a significant role in diagnosis at the present time. The diagnosis information is also important particularly in patient treatment data, the results and other confidential information which cannot be disclosed according to judgment and ethics. These data are exported with the images and will be protected generally. This article presents a high-efficiency technique for hiding information...
In this paper, we analyze the effect of time-varying channels to video codec buffer specially for low-delay applications. We derive the sufficient conditions under which an encoder can design a bitstream for any time-varying channel without decoder buffer overflow and underflow. We then apply those conditions to design a bandwidth adaptive rate control in x264 and test it under LTE simulator. Our...
The deblocking filtering for multiview video coding plays a major role in improving the image visual quality, but it has high computation complexity. This paper proposes a perceptual deblocking filtering algorithm based on just noticeable distortion model. By properly considering of the human visual characteristic, a perceptual deblocking filtering decision is integrated into the deblocking process...
In Wyner-Ziv video coding architectures, the available bit budget to each GOP is shared between key frames and Wyner-Ziv frames. In this work, we first propose a model to express the relationship between quantization step size of key and WZ frames based on their motion activity. Then we apply this model to propose an adaptive algorithm adjusting the quantization step size of key and WZ frames to achieve...
High Efficiency Video Coding (HEVC) is the next-generation video coding standard currently under development, which has demonstrated substantial bit savings (rate reduction by approximately half) compared to H.264/AVC. This paper presents the multiple sign bits hiding scheme that was adopted into the committee draft of HEVC at the 8th JCT-VC meeting. In HEVC, the quantized transform coefficients are...
This paper presents a joint source/channel coding method in 3D-JPEG2000 for wireless transmission of 3D regions of interest (RoIs) in 3D medical images. The method provides unequal error protection by combining the error correction capabilities of channel codes with the 3D-JPEG2000 error resilience tools. It generates quality scalable and error-resilient codestreams with 3D-RoI decoding capabilities...
This paper presents the performance evaluation results of 3D Video Streaming using a H.264/MVCexperimental platform. Particular attention has been given to the evaluation of different video bit stream RTP packetizationmodes, namely Single NAL Unit, Aggregation Packet and Fragmentation Units, by measuring overhead, number of decoded frames and perceived PSNR for both base and non base view under different...
In this paper we explore a method to encode/decode multiview textures and associated supplementary data (depth map as an example) together in a single bitstream. Least significant bit (LSB) of last two levels in each transform block has been modified according to the depth encoded bits, thus resulting in very minimal loss in PSNR of textures (0.1 – 0.5dB) with overall bitrate gain of about 13% for...
During transmission, compressed video streams of H.264/AVC are very likely to be corrupted by channel distortion. In order to resolve the problem, researchers come out with a solution called error concealment which is done at the decoder side. In this paper we conduct a research on BMA and the motion compensated error concealment methods. Compared with BMA, the MCEC algorithm is capable of providing...
To keep constant video quality is one of the key issues in video coding application, so quality control is a crucial while difficult subject for either the traditional video coding or distributed video coding. In this paper, we propose a quality control algorithm through using distortion quantization (DQ) model to decide quantization step for the next Wyner-Ziv frame with the purpose of the distortions...
An investigation of joint source channel decoding (JSCD) methods using BPSK modulation applied to a vector quantization of compressed sub band coded source in Communication Network is presented. The proposed decoding scheme designed a feedback algorithm using error-detected source information to improve the error correction capability of the Turbo Log-MAP decoder without changing its constituent decoder...
In texture-plus-depth format of 3D visual data, texture and depth maps of multiple viewpoints are coded and transmitted at sender. At receiver, decoded texture and depth maps of two neighboring viewpoints are used to synthesize a desired intermediate view via depth-image-based rendering (DIBR). In this paper, to enable transmission of depth maps at low resolution for bit saving, we propose a novel...
This paper proposes a novel three dimensional video (3DV) coding scheme, in which down-/up-sampling filters and asymmetrical prediction (ASP) are involved into the coding system. By using of the down-/up-sampling filters, the 3DV data volume requirement of the decoding capability limitations can be well satisfied. To further improve the coding efficiency, ASP is proposed which enables the inter-view...
Most common video coding standards employ spatiotemporal prediction techniques to increase coding efficiency. As a result, compressed video data is sensitive to the transmission error due to error propagation. An adaptive reference picture selection (RPS) is proposed to improve the error resilience in real-time video transmission. A global rate-distortion optimization (RDO) is developed to intelligently...
In this work, a novel method for color video compression using key-frame based color transfer has been proposed. In this scheme, compression is achieved by discarding the color information of all but few selected frames. These selected frames are either the key frames (frame selected by a key frame selection algorithm) or the Intra coded (I) frames. The partially colored video is compressed using...
A conventional synchronous single processor decoder system can no longer cater to the demands of the market in terms of processing speed. A modern asynchronous multiprocessor architecture partitions the decoding functions into different processing cores so that real time decoding of high mega pixel streams is achieved by parallel execution. The number of processor cores is a balance between chip area,...
In this work we compare state-of-the-art 3D coding technologies which are suitable for compression of 3D (volumetric) medical imagery. Our aim is to assess the usage of these methods on representative large datasets, also keeping into account relevant features related to modern application requirements. This work wants to be a useful reference for those interested in medical image coding technologies...
Wyner-Ziv video coding (WZVC) is very attractive for low power wireless video sensors. In this paper we show that how the transmission bit-rate of WZVC can be further reduced when multiple uncorrelated wireless receiving points are deployed at the decoder. This is different from classical SIMO in the sense of cross layer coding is deployed. When the wireless channel degrades, decoder is fed with an...
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