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This paper designed an audio driver based on ASoC framework. All the work was based on Linux operator system which is composed of Exynos4412 microprocessor and wm8960 codec audio chips. In the system, the audio driver can drive multiple codec cards, the I2C bus is used to transmit the control information to the audio chip, and the I2S bus is used to transmit the audio data. ASoC audio driver architecture...
The impulse-sequence representation of the excitation source information in normal speech signal has been explored for speech coding. Such a representation, if can be developed for paralinguistic and emotional speech sounds, would help in their acoustic analyses. This paper proposes a sparse representation of the excitation source characteristics of nonnormal speech sounds signal, in terms of a time-domain...
This letter presents a perceptually weighted analysis-by-synthesis vector quantization (VQ) algorithm for low bit rate MFCC codec. Different from conventional VQ of mel-frequency cepstral coefficients (MFCCs) vector, this algorithm uses an analysis-by-synthesis technique and aims to minimize the perceptually weighted spectral reconstruction distortion rather than the distortion of MFCCs vector itself...
We propose an end-to-end approach to describe the energy usage of video delivery within a content delivery framework, and use this to investigate the energy usage behavior of two popular coding schemes, namely, H.264/AVC and H.265/HEVC. Our study based on the proposed model is backed up by measurements of encoding and decoding energy usage of a sample video and shows that, from an end-to-end perspective,...
Current research works have looked at improving the IPsec secured VoIP by arbitrarily increasing bandwidth which is a very limited resource and cannot just be increased in real environments except under laboratory conditions. Also, in most earlier works, codec has been kept constant and the IPsec impact analysed. The results of such works undoubtedly show the devastating impact IPsec has on VoIP which...
In this paper, a new way of evaluating image compression performance is proposed in order to reflect the human visual perception perspective in image compression and its applications: “No noticeable difference (NND) is allowed in commercial use.” Various methodologies have been proposed and utilized to evaluate image compression performance with both objective and subjective measures for the given...
It is of vital importance to make audiovisual quality assessment, as the growing demand on video telephone services. Users are more enjoying higher quality of video telephone, and their perceptions on video telephone service will directly influence the service provider's performance. So it is significant to study end users' subjective perception, named as Quality of Experience (QoE), on video telephone...
VoWiFi or deployment of VoIP over wireless medium can facilitate campus-wide provisioning of IP-based voice service. Determining the performance and capacity limits is essential for proper dimensioning of the service in an enterprise. This paper analyzes the real-time performance of an economical RasPBX based Asterisk system for VoWiFi service in terms of voice capacity and quality. The call blocking...
This paper proposes a new scheduling scheme which based on the extended E-model, Channel- and QoS- Aware (known as E-MQS scheduler) for real-time traffics in LTE downlink direction. The real-time services (VoIP, Video, etc.) are very sensitive to network impairments such as delay, packet loss, jitter, etc. The proposed scheduling scheme is based on the extension of the E-model and the consideration...
Predictive analytics techniques can tremendously improve the performance of computing systems by optimizing energy, waiting time and throughput via predicting the execution time of scheduled jobs beforehand. As a consequence of the correlation between video conversion parameters and video conversion time, the conversion time is highly predictable from input video properties and conversion parameters...
With the recent standardization of the Enhanced Voice Services (EVS) codec in 3GPP, mobile operators can upgrade their voice services to offer super-wideband (SWB) audio quality (with 32 kHz sampling rate). There is however one important use case which is currently limited by existing standards: hands free communication with wireless headsets, car kits, or connected audio devices often rely on Bluetooth,...
The inter-regional telecommunication network design in Indonesia is strongly influenced by the bandwidth of Voice over Internet Protocol (VoIP), where 40% of the national bandwidth is used to pass voice communication. Indonesia region is divided into seven regional areas; each of these is supported by two IMS Cores, which serves as the active core and the stand-by core. Regionals are interconnected...
Sparse representation is a common approach for reducing the spatial redundancy by modelling an image as a linear combination of few atoms taken from an analytic or trained dictionary. This paper introduces a new image codec based on adaptive sparse representations wherein the visual salient information is considered into the rate allocation process. Firstly, the regions of the image that are more...
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...
We introduce a constant luminance HDR video coding pipeline, which converts the source video to linear Y u'v' color space and applies a dedicated chromaticity transformation before encoding. This reduces perceivable color artifacts without modifying the core codec itself. We validate our approach by a user study that shows a significant improvement in perceived color quality at high compression rates...
This paper introduces row-column transforms (RCTs) which are 2D non-separable transforms defined with the aid of a set of 1-D linear transforms and a basis ordering permutation. We propose a novel method for the design of row-column transforms that approximate desired complex transforms (such as KLTs, SOTs, etc.) so that most of the performance of the approximated transforms is retained at significantly...
While a number of existing high-bit depth video compression methods can potentially encode high dynamic range (HDR) video, few of them provide this capability. In this paper, we investigate techniques for adapting HDR video for this purpose. In a large-scale test on 33 HDR video sequences, we compare 2 video codecs, 4 luminance encoding techniques (transfer functions) and 3 color encoding methods,...
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...
Video codecs exploit temporal redundancy in video signals, through the use of motion compensated prediction, to achieve superior compression performance. The coding of motion vectors takes a large portion of the total rate cost. Prior research utilizes the spatial and temporal correlation of the motion field to improve the coding efficiency of the motion information. It typically constructs a candidate...
This paper reveals the potential gain in audio quality that can be achieved by combining Spherical Logarithmic Quantization (SLQ) with advanced broadband error robust low delay audio coding based on ADPCM. We briefly summarize the basic properties and mechanisms of SLQ and the employed ADPCM scheme and show how they can be combined in a freely parameterizable coding algorithm. The resulting codec...
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