The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The JPEG committee (formally, ISO SC29 WG1) is currently standardizing a lightweight mezzanine codec for video over IP transport under the name JPEG XS. A particular challenging design constraint of this codec is multi-generation robustness, that is the necessity to minimize the error built-up under multiple re-compression cycles. In this paper, we discuss the sources of such errors, how they are...
This paper presents a method to extract rendering matrix on multi-channel audio signals as an object fed to Moving Picture Expert Group Spatial Audio Object Coding (MPEG SAOC) encoder. This technique allows MPEG SAOC to transmit multiple multi-channel audio objects, instead of only a single multi-channel background object as specified in MPEG SAOC standard. Listening tests show that the proposed method...
In order to improve the error resistance and security of JPEG2000 standard, a joint source channel and security arithmetic coding/decoding scheme for EBCOT in JPEG2000 is proposed. Based on error resistant arithmetic coding, this scheme inserts multiple forbidden symbols and generates secure two-way decodable bitstream controlled by chaotic maps, improving the security of the scheme. Meanwhile, at...
The latest High Efficiency Video Coding (HEVC) has been increasingly used to generate video streams over Internet. However, the decoded HEVC video streams may incur severe quality degradation, especially at low bit-rates. Thus, it is necessary to enhance visual quality of HEVC videos at the decoder side. To this end, we propose in this paper a Decoder-side Scalable Convolutional Neural Network (DS-CNN)...
MPEG-4 high efficiency (HE) advanced audio coding (AAC) contains a useful tool called spectral band replication (SBR) to improve the coded audio quality at low bitrates. The SBR tool uses start-band frequency to determine from which frequency band replication starts. This paper describes an algorithm to dynamically determine this parameter based on the genre of the music content. The simulation results...
This paper improves a colorization-based image coding using image segmentation and adaptive colorspaces. Recently, various approaches for color image coding based on colorization have been presented. These methods utilize a YCbCr colorspace and transfer the luminance component by a conventional compression method. Then, the chrominance components are approximated from the luminance component using...
360° video streaming to clients using Virtual Reality head mounted displays is a challenge for traditional video delivery. As transmission of the complete content in a desirable quality sacrifices a large fraction of available client and network resources, adaptivity to the user viewport promises substantial benefits. An efficient way to achieve viewport adaptive streaming without per-user or per-orientation...
A video analyzer is a comprehensive bitstream analysis tool which accelerates development and debugging of video bitstreams while ensuring compliance with industry standards. There are many conventional analyzers present for different video standards like H.264, HEVC which are compliant only with the respective video sequence format. In this work, a generalized analyzer with integrated encoder is...
A novel perceptual multiple description coding with randomly offset quantizers (PMDROQ) is proposed. In the proposed PMDROQ method, the input image is partitioned into M subsets, and then obtaining M descriptions. In each description, one subset is directly encoded and decoded with different-small perceptual quantization stepsizes in DCT domain, while other subsets are predictively coded and decoded...
At low bit-rates, the conventional image coding standards, e.g., JPEG and JPEG 2000, do not have good compression performance due to the insufficiency of coding bits. A common solution to this problem is downsampling before encoding and reconstruction after decoding. Inspired by the wavelet domain downsampling-based compression scheme, we establish an enhanced low bit-rates coding framework by making...
In this paper, we propose a rate-constrained distributed video coding-based region of interest (ROI) coding scheme. The proposed scheme appropriately determines ROI according to an available bit budget that depends on transmission channel and decoding environment. Its subjective quality is faithfully maintained via adaptive ROI definition of the available resources. Prior knowledge about the ROI is...
We propose an algorithm that accomplishes transform-coded, spatiotemporal, pel-recursive video compression. Traditional pel-recursive coders obtain sophisticated spatio-temporal predictions for the current pixel based on previously decoded data. The resulting per-pixel prediction errors are encoded independently so that the decoder can use previously-encoded pixels in the prediction of the current...
Our challenge is the design of a “universal” bit-efficient image compression approach. The prime goal is to allow reconstruction of images with high quality. In addition, we attempt to design the coder and decoder “universal”, such that MPEG-7-like low-and mid-level descriptors are an integral part of the coded representation. To this end, we introduce a sparse Mixture-of-Experts regression approach...
The upcoming JPEG XT standard for High Dynamic Range (HDR) images defines a common framework for the lossy and lossless representation of high-dynamic range images. It describes the decoding process as the combination of various processing tools that can be combined freely. In this paper we analyze the coding efficiency of different decoding tools through a large scale objective quality testing using...
This paper studies the influence of JPEG-XT on LDR generation using TMOs'. JPEG-XT encodes HDR images into a two layer scheme, encoding a LDR version of the image in a base layer, and the residual HDR information in an enhancement layer. The question addressed here is to understand if this model allows to extract a new LDR representation using a different TMO, independently of the TMO used to generate...
We present a novel lossless image compression algorithm. It achieves better compression than popular lossless image formats like PNG and lossless JPEG 2000. Existing image formats have specific strengths and weaknesses: e.g. JPEG works well for photographs, PNG works well for line drawings or images with few distinct colors. For any type of image, our method performs as good or better (on average)...
Light field imaging is a promising new technology that allows the user not only to change the focus and perspective after taking a picture, as well as to generate 3D content, among other applications. However, light field images are characterized by large amounts of data and there is a lack of coding tools to efficiently encode this type of content. Therefore, this paper proposes the addition of two...
Decorrelator is a module to restore the specific correlation properties between stereo signals in parametric stereo audio decoder, which is vital to keep the spatial information of the stereo signals. Generally, the existing decorrelators are prone to have a comb-filter effect which results in an undesirable “metallic” sound and produce temporal smearing such as pre- and post-echoes artefacts. This...
A networked controlled system (NCS) in which the plant communicates to the controller over a channel with random delay loss is considered. The channel model is motivated by recent development of tree codes for NCS, which effectively translates an erasure channel to one with random delay. A causal transform coding scheme is presented which exploits the plant state memory for efficient communications...
The coding performance of the normative encoder of the JPEG XT in profile is analyzed and the problem on the encoder is summarized in this paper. It is pointed out that there is a mismatch in the handling of the quantization error between the normative encoder and the standard decoder. To avoid this problem, an improved structure has been proposed with consideration of the mismatch. The experimental...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.