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The paper presents a VLSI architecture of three dimensional discrete cosine transform (3D DCT) for video recent compression. By making use of the separability property of DCT, the 3D DCT is decomposed into 1D DCTs computed in each of the three dimensions. Each 1D DCT is carried out as an integer DCT using the butterfly structure. It is useful for reducing the computation time and also makes our structure...
An image pre-processing approach is proposed for joint source-channel coding (JSCC) scheme based on double protograph low-density parity-check (DP-LDPC) codes. Firstly, discrete cosine transform (DCT) and quantization are applied to the transmitted images. Different from the data processing of the previous approach for the quantized DCT coefficients, the representation of true form takes the place...
Data transmission in a secure manner over the internet has gained higher interest since last decade as the use of encryption for transmitting embedded files before compression is very essential. The major challenge is designing the architecture so as to perform the file encryption at sender side and the file compression at the NSP side in order to achieve the distinguished works assigned to senders...
Daala is a new royalty-free video codec that attempts to compete with state-of-the-art royalty-bearing codecs. To do so, it must achieve good compression while avoiding all of their patented techniques. We use technology that is as different as possible from traditional approaches to achieve this. This paper describes the technology behind Daala and discusses where it fits in the newly created AV1...
In this paper, a compressed domain drift compensated reversible watermarking scheme is proposed with a high embedding capacity and the least amount of visual quality degradation for H.265/HEVC videos. Using compressed domain syntax elements, such as motion vector and transformed residual, a set of 4 × 4 Transform Blocks (TB) of similar texture are chosen from consecutive I Frames for watermark embedding...
Many approaches have been proposed to support lossless coding within video coding standards that are primarily designed for lossy coding. The simplest approach is to just skip transform and quantization and directly entropy code the prediction residual, which is used in HEVC version 1. However, this simple approach is inefficient for compression. More efficient approaches include processing the residual...
In intra video coding, intra frames are predicted with intra prediction and the prediction residual signal is encoded. In many transform-based video coding systems, intra prediction residuals are encoded with transforms. For example, the Discrete Cosine Transform (DCT) and the Asymmetric Discrete Sine Transform (ADST) are used for intra prediction residuals in many coding systems. In the recent work,...
This paper introduces a novel class of transforms, called graph-based separable transforms (GBSTs), based on two line graphs with optimized weights. For the optimal GBST construction, we formulate a graph learning problem to design two separate line graphs using row-wise and column-wise residual block statistics, respectively. We also analyze the optimality of resulting separable transforms for both...
The accuracy of end-to-end distortion (EED) estimation is crucial to achieving effective error resilient video coding. An established solution, the recursive optimal per-pixel estimate (ROPE), does so by tracking the first and second moments of decoder-reconstructed pixels. An alternative estimation approach, the spectral coefficient-wise optimal recursive estimate (SCORE), tracks instead moments...
In this paper, we propose a new edge model for edge adaptive graph-based transforms (EA-GBTs) in video compression. In particular, we consider step and ramp edge models to design graphs used for defining transforms, and compare their performance on coding intra and inter predicted residual blocks. In order to reduce the signaling overhead of block-adaptive coding, a new edge coding method is introduced...
This paper presents efficient SIMD optimizations for the open-source Kvazaar HEVC intra encoder. The C implementation of Kvazaar is accelerated by Intel AVX2 instructions whose effect on Kvazaar ultrafast preset is profiled. According to our profiling results, C functions of SATD, DCT, quantization, and intra prediction account for over 60% of the total intra coding time of Kvazaar ultrafast preset...
Despite its age, JPEG (formally, Rec. ITU-T T.81 — ISO/IEC 10918-1) is still the omnipresent image file format for lossy compression of photographic images. While its rate-distortion performance is not competitive with state-of-the-art schemes like JPEG 2000 or HEVC, manifold techniques have been developed over the years to improve its compression performance. This article provides a short review...
Demand for screen content videos that contain computer generated text and graphics is growing. They are very different from natural videos, because they include much sharper edge transitions and very repetitive patterns. On this type of material, the efficacy of the conventional discrete cosine transform (DCT) is questionable because it relies on the assumption that a Gauss-Markov model leads to a...
It is desirable to support efficient lossless coding within video coding standards, which are primarily designed for lossy coding, with as little modification as possible. A simple approach is to skip transform and quantization, and directly entropy code the prediction residual, but this is inefficient for compression. A more efficient and popular approach is to process the residual block with DPCM...
This paper presents a lightweight video sensor node for moving object surveillance using region-of-interest (ROI) based coding and an on-line multi-parameter rate controller. The proposed ROI-based coding scheme determines ROI blocks, pre-processes non-ROI blocks using bit-truncation, and encodes all blocks using Motion JPEG. The on-line rate controller modulates the parameters of the ROI-based coding...
The new video coding standard, high efficiency video coding (HEVC) had been finalized in 2013. Its transform unit (TU) adopts a quadtree structure to provide variable sizes of integer discrete cosine transform (DCT) for transform coding. The quadtree structure of TU increases the coding efficiency, but the computational complexity also increases, compared with previous video coding standards. Thus,...
The paper uses EMD to construct a new transformation matrix to improve the original matrix coding algorithm and proposes a new video steganography algorithm:Improved Matrix Encoding (IME). The proposed algorithmretains the advantages of EMD and matrix encoding that it can greatly reduce the modifications of embed carrier to achieve a high embedding efficiency under the conditions of same embedding...
Discrete Cosine Transform (DCT) has been the commonly used transform for a few decades in image/video coding. However, DCT does not work well on the blocks having anisotropic correlations. In this paper, based on the adaptive dictionary, we propose a new online transform scheme using Orthogonal Matching Pursuit (OMP) for High Efficiency Video Coding (HEVC). For a coding block, we construct its dictionary...
In a distributed video coding problem, use of a correct model for the correlation noise plays a significant role in improving the decoding performance and consequently in providing higher coding efficiency. In this work, we first study the predictive and additive correlation noise models at the DCT coefficient band level for transform-domain distributed video coding. Then, bounds on compression rates...
Electrocardiogram (ECG) is one testing method for measuring electrical activity of heart. ECG is the graphical representation of the electrical signal generated from heart. Heart is an organ of human which pump blood for the entire body. It require huge amount of data to store and transmit these ECG signals. So it is necessary for compression of the ECG signals. In few last years, many algorithms...
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