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In video coding, quality evaluation is important for improving the coding efficiency. Usually Peak Signal-to-Noise Ratio (PSNR) is utilized to measure the performance of different coding techniques. During the video coding process in YCbCr color space, there are three PSNRs, one for each color component. Sometimes they may contradict to each other, which poses a problem for evaluating the coding performance...
The paper reports research on original techniques for compression of chrominance data in video sequences transmitted at very low bit rates. Two chrominance components are converted into one scalar chrominance signal using vector quantization in chrominance plane. Three methods for scalar chrominance compression based on transform and predictive coding are described. The important issue is that presented...
In this paper, an error concealment method for transmission of 3D video in color+depth dual stream format is proposed. Exploiting the correlation between 2D color video and its corresponding depth information, recovery of the lost information of one kind (color/depth) can be achieved with the aid of received information from the other kind (depth/color), thus getting better concealed results than...
An efficient coding algorithm for depth map images and videos, based on view synthesis distortion estimation, is proposed in this work. We first analyze how a depth error is related to a disparity error and how the disparity vector error affects the energy spectral density of a synthesized color video in the frequency domain. Based on the analysis, we propose an estimation technique to predict the...
In this paper, the fractal Image Compression technique proposed by Jacquin is investigated for 24 bits/pixel color image with some improvements introduce on the IFS matching stage. One of them is using stopping search condition (e ) when monitoring the minimum matching error. This will reduce the required long fractal coding time. The other is using the domain block position index (PosI) instead of...
Recently, several steganographic methods, based on bitplane analysis have been developed. These methods improve the classical LSB method, generally by increasing the number of bitplanes via sophisticated encodings. In this paper, we show that these methods can be unified with the use of sub-Fibonnaci sequences. The huge number (trillions of them) of these sequences gives us the advantage to use them...
In this paper, we present a model-based video coding method that uses input from colour and depth cameras, such as the Microsoft Kinect. The model-based approach uses a 3D representation of the scene, enabling several other applications besides video playback. Some of these applications are stereoscopic viewing, object insertion for augmented reality and free viewpoint viewing. The video encoding...
Emerging video technologies like 3DTV and Free Viewpoint Video require to transmit more information than just 2D color data. To allow rendering of arbitrary viewpoints of a video scene a new data format including 2D color and an accompanying depth map has been proposed. Consequently this new technique requires an efficient coding method not only for color information, but also for depth data. Depth...
Intra coding in the current H.264/AVC video coding standard achieves high compression efficiency, in part due to the highly effective intra prediction process that exploits spatial directional correlation. However, intra prediction of chroma components in YUV 4:2:0 videos uses a limited set of possible predictions available for coding of luma components. Furthermore, coding of chroma components proceeds...
Because of the color data from different views may differ greatly between various views in multiview video coding(MVC), Color correction is used to improve the MVC coding efficiency. This paper proposes a foreground based disparity vector estimation algorithm. Using with LSM color correction method, the proposed algorithm can improve the reliability and efficiency of color correction of MVC. Compared...
In multiview video representation, one of the most popular format is the so-called multiple view video plus depth. This representation is made up of N image sequences, each accompanied by a sequence of depth maps, telling the distance of each represented pixel from the observing camera. The depth maps are needed at the decoder side in order to generate intermediate views and therefore to enrich the...
Multi-view Video Coding (MVC) employs both motion and disparity estimation within the encoding process. These provide a significant increase in coding efficiency at the expense of a substantial increase in computational requirements. This paper presents a fast motion and disparity estimation technique that utilizes the multi-view geometry together with the depth information and the corresponding encoded...
In 3DTV and free viewpoint imaging systems based on a view-plus-depth representation, depth compression is important for high-quality view synthesis. Several publications have proposed depth down-/up-sampling as part of the depth coding strategy. Recently, we proposed a depth up-sampling method which uses the high resolution view in the process of depth up-sampling. Actually, in 2007 Kopf et.al. already...
This paper discusses bit-rate assignments for vertices, color, reference frames, and target frames in the patch-based compression method for time-varying meshes (TVMs). TVMs are nonisomorphic 3D mesh sequences of the real-world objects generated from multiview images. Experimental results demonstrate that the bit rate for vertices greatly affects the visual quality of the rendered 3D model, whereas...
3D scene information can be represented in several ways. In applications based on a (N-)view plus (N-)depth representation, both view and depth data is compressed. In this paper we present a depth compression method containing an depth up-sample filter which uses the color view as prior. Our method of depth down-/up-sampling is able to maintain clear object boundaries in the reconstructed depth maps...
We propose a novel 3D space representation for multi-view video, using epipolar plane depth images (EPDI). Multi-view video plus depth (MVD) is used as common data format for FTV(Free-viewpoint TV), which enables synthesizing virtual view images. Due to large amount of data and complexity of the multi-view video coding (MVC), compression of MVD is a challenging issue. We address this problem and propose...
In this report, permutation of order and sign of signals are introduced to avoid singular point problem of a reversible transform. When a transform is implemented in the lifting structure, it can be "reversible" in spite of rounding operations inside the transform. Therefore it has been applied to lossless coding of digital signals. However some coefficient values of the transform have singular...
RGB color signals encoding is more desirable for high resolution and accurate definition for saturations and hue. This paper presents a region adaptive inter-color prediction scheme for 4:4:4 RGB signals, which treats G component as a primary component and predicts B/R component from G component with different weighting factors based on different texture regions. The proposed algorithm demonstrates...
In this paper, an adaptive color transform for image compression is introduced. In each block of the image coefficients of the color transform are determined from the previously compressed neighboring blocks using weighted sums of the RGB pixel values, making the transform block-specific. There is no need to transmit or store the transform coefficients because they are estimated from previous blocks...
In order to increase coding efficiency, a perception-aware H.264/AVC encoder is proposed in this paper. With a different perception models for intra-frames and inter-frames, the initial quantization parameter (QP) is perceptually adjusted to remove perceptual redundancy. Moreover, the associated hardware architectures of the whole encoder and the perception analysis engine are also proposed with hardware...
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