Image description for coding using triangular patch structure

In this paper, the radiative near‐field method has been employed to transfer power through a triangular patch microstrip array that had not been used for this application previously. Additionally, the FR4 substrate is utilized to further reduce the system cost. The system comprises two identical array antennas functioning as both transmitter and receiver. Each array consists of four triangular patches with a side length of 38.5 mm and operates at a frequency of 2.4 GHz. The distance between the two arrays is 50 mm, placing the system in the radiative near‐field category of wireless power transfer. This two‐array system enables the evaluation of power transfer efficiency. The system's performance is improved compared to that of a single triangular patch, and it is also studied in terms of changes in distance. As expected, reducing the distance enhances the system's performance. Subsequently, the structure is fabricated, and the measurements validate the simulation results. The simulation and measurement results exhibit good agreement.

This paper presents the design and simulation of 30°-30°-120° triangular microstrip patch antenna miniaturization using shorting pin for S-band frequency operation. The analysis of miniaturized triangular microstrip antenna with shorting pin is performed by Ansys HFSS based simulation results. The conventional and compact triangular microstrip patch antenna shows the resonant frequency at 2.2 GHz and 2.4 GHz with gain of 1.2 dB and 1.7 dB respectively. Here the conventional triangular microstrip patch antenna area is miniaturized upto 31% through the shorting pin. The comparison between the conventional and compact triangular microstrip patch antenna are presented and discussed in this paper. The proposed compact triangular microstrip patch antenna is often suitable for integration with Bluetooth and WLAN devices with reduced design complexity.

A miniaturized wideband and multi-band on-demand reconfigurable antenna for compact and portable devices

The shape of the radiating patch in the microstrip patch antenna is one of the many factors that affect the performance of the microstrip antenna.In this paper, on the premise of center frequency of 2.45 GHz, rectangular, circular and triangular microstrip patch antennas are designed and simulated respectively.The simulation results of the three microstrip patch antenna are analyzed, such as feed point position, return loss and radiation patterns.The influence of the shape of the radiation patch on the impedance bandwidth, gain and directivity of microstrip antennas is discussed.The simulation results show that the comprehensive performance of rectangular microstrip patch antenna is better than the other two, the comprehensive performance of triangular microstrip patch antenna is poor.

A new feedforward control method to control encod-ing parameters is proposed for low bit rate video encoding. At low transmission bit rates, all input video frames cannot be transmitted and an encoding frame interval varies with the information amount in each encoded frame. Subjective video quality is evaluated from both picture degradation and encoding frame intervals. Because picture degradation and encoding frame intervals are traded off, encoding parameter control is very important. The proposed method is based on a hybrid transform predictive coding scheme with adaptive coefficient selection. The method estimates the amount of information for some encoding parameters and selects parameters so that given control characteristics can be achieved. Computer simulations for both the proposed method and a conventional feedback method show the effectiveness of the new method. This method will be applied to an NETEC series low bit rate video codec.

Based on the theory of light energy transfer between two differential diffuse surface areas, a generalized radiosity approach is presented. Unlike the conventional radiosity method, curved surfaces are subdivided into triangular surface patches, radiosity is assummed to be vary across each triangular surface patch. By adopting linear interpolation scheme over each triangular surface patch, we have established a complete set of approximated radiosity equations. Their unknowns are radiosities of differential surface areas located at all vertices of surface patches. The generalized radiosity equation has also been extended to non‐diffuse environments. Theoretical analysis and experimental results demonstrate the great potential of this method,

We present a technique to estimate the optical flow in an image sequence, based on a piecewise affine model. In this piecewise approach, the area of interest in each image frame is divided into a set of small triangular patches. These triangular meshes are established over a set of feature points, which are extracted from the images and tracked from one frame to another. The velocity field within each triangular patch is parameterized by an affine transform. A multiscale coarse-to-fine approach is employed to increase the robustness of the method as well as the accuracy of the optical flow resulted from piecewise affine approximations. Finally, an adaptive filter is used to refine the estimated flow field. The filter is designed in such a way that not only can it reduce noises caused by errors of the process described above, but it can also avoid smoothing the discontinuities in the motion field. The method has been implemented and some experimental results are presented in this paper. The method takes advantage of widely used MPEG-4 encoding hardware/software tools

Digital image transmission is widely used in consumer products, such as digital cameras and cellular phones, where low bit rate coding is required. In any low bit rate encoder, such as the JPEG2000 standard, data truncation (during the encoding process), and data loss (during transmission) will result in lost bit-planes, which will be normally replaced by zeros. In this paper a new algorithm has been proposed, which recovers the lost/truncated lower bit-planes of coefficients in the LL subband of a wavelet transform in a JPEG2000 stream using the data available in higher bit-planes of the same coefficient and its eight neighbors. Simulation results indicate that the proposed algorithm achieves 5.40-8.77 dB improvement with respect to zero filling data recovery method.

<b>Problem statement:</b> In modern speech communication at low bit rate, speech coding deteriorates the characteristics of the coded speech significantly. Considering the dialects in Thai, the coding quality of four main dialects spoken by Thai people residing in four core region including central, north, northeast and south regions has not been studied. <b>Approach:</b> This study presents a comparative study of the coding quality of four main Thai dialects by using different low-bit-rate speech coders including the Conjugate Structure Algebraic Code Excited Linear Predictive (CS-ACELP) coder and the Multi-Pulse based Code Excited Linear Predictive (MP-CELP) coder. The objective and subjective tests have been conducted to evaluate the coding quality of four main dialects. <b>Results:</b> From the experimental results, both tests show that the coding quality of North dialect is highest, meanwhile the coding quality of Northeast dialect is lowest. Moreover, the coding quality of male speech is mostly higher than that of female speech. <b>Conclusion:</b> From the study, it can be obviously seen that the coding quality of all Thai dialects are different.

This paper is concerned with the subjective selection of image details for segmentation-based very low bit-rate coding. An approach is proposed for extracting image details and ranking the details in the order of perceptual significance to the human visual system (HVS). A perceptual ranking model has been established by multivariate regression analysis based on the data obtained from subjective tests. In terms of the correlation between the objective ranking and subjective ranking of perceptual significance and subjective image quality, this model provides better results in detail ranking than that provided by an empirical ranking formula proposed in a previous study. Segmented regions and selected details are coded to illustrate the efficiency of coding meaningful details. Compared with the pure segmented images, the addition of the selected details improves the subjective image quality at lower bit rates.

With the rapid growth of Internet video image information, there is a large amount of redundancy in image data. Use less data stream information to transfer the image or the amount of information contained in the image. Its purpose is to reduce the redundancy of images, so as to store them at low bit rate and reduce the data storage space. In the general image compression method, the hybrid coding framework is adopted. Each algorithm adopts a fixed algorithm mode through a specific design algorithm, without global optimization. Image compression is mainly divided into prediction, transformation, quantization, digital entropy coding and other steps. At present, there are many researches on super-resolution network based on deep learning technology. The main function is to reconstruct high-resolution image replace image magnification low-resolution images such as linear interpolation, which has a great performance improvement image resolution, noise reduction, deblurring and so on, but there is no effective way to use super-resolution network applications to improve quality of compression reconstructed image quality. This paper involves a new method that using image super-resolution residual learning network to improve quality of compression image, our method, the reduced image is encoded into a content stream and a transmission corresponding parameter is encoded into a model stream. Firstly, the original image is scaled down 1/2 size of source image, then encode the small image into content stream with the existing codec. Secondly, the residual learning super-resolution (SR) network is used for image filtering to scale up reconstructed image with decode image resizing method and boost the quality of edge feature extraction of image. Our results show that there is significant performance improvement of h265 in low resolution reconstructed image (bits-per-pixel less than 0.1).

A fundamental issue in real-time interactive voice transmissions over unreliable IF networks is the loss or late arrival of packets for playback. This problem is especially serious when transmitting low bit rate-coded speech with pervasive dependencies introduced. In this case, the loss or late arrival of a single packet will lead to the loss of subsequent dependent frames. We study end-to-end loss-concealment schemes for ensuring high quality in playback. We propose a novel multiple description-coding method for concealing packet losses in transmitting low bit rate-coded speech. Based on high correlations observed in linear predictor parameters-in the form of Line Spectral Pairs (LSPs)-of adjacent frames, we generate multiple descriptions in senders by interleaving LSPs, and reconstruct lost LSPs in receivers by linear interpolations. As excitation codewords have low correlations, we further enlarge the segment size for excitation generation and replicate excitation codewords in all the descriptions in order to maintain the same transmission bandwidth. Our proposed scheme can be extended easily to more than two descriptions and can adapt its number of descriptions dynamically to network-loss conditions. Experimental results on FS-1016 CELP, ITU G.723.1, and FS MELP coders show good performance of our scheme.

Point cloud boundary is an important part of the surface model. The traditional feature extraction method has slow speed and low efficiency and only achieves the boundary feature points. Hence, the point cloud feature regularization is proposed to obtain the boundary lines based on the fast extraction of feature points in this article. First, an improved k-d tree method is used to search the k neighbors of sampling point. Then, the sampling point and its k neighbors are used as the reference points set to fit a microcut plane and project to the plane. The local coordinate system is established on the microcut plane to convert 3-D into 2-D. The boundary feature points are identified by judging criterion of field force and then are sorted and connected according to the vector deflected angle and distance. Finally, the boundary lines are smoothed by the improved cubic B-spline fitting method. Experiments show that the proposed method can extract the boundary feature points quickly and efficiently, and the mean error of boundary lines is 0.0674 mm and the standard deviation is 0.0346 mm, which has high precision. This proposed method was also successfully applied to feature extraction and boundary fitting of Xinyi teaching building of the Wuhan University of Technology.

A position prediction method is proposed for optical fiber disturbances based on a regression model of semiconductor laser reservoir computing (SL-RC). An in-line Sagnac interferometric distributed optical fiber sensing (DOFS) system is built in OptiSystem software and the interference signals are collected at partial sensing positions. The occurrence time of each waveform-change in the interference signal is extracted to construct a feature vector as the input of the SL-RC. Based on the rate equations of a semiconductor laser with optical injection and optical feedback, the SL-RC regression model is established. Through the work flow of RC, the position prediction of the optical fiber disturbance is achieved, and a mean absolute error is 0.69 m in a sensing distance of 1 km. The simulation results indicate that the proposed method can quickly and accurately predict any sensing position with a small amount of data, and has the potential for location in the optical domain.

Lip segmentation is an essential stage in many multimedia systems such as videoconferencing, lip reading, or low bit rate coding communication systems. In this paper, we propose an accurate and robust lip segmentation algorithm. First, the upper mouth boundary and several characteristic points are detected by using a new kind of active contour : the jumping snake. Unlike classic snakes, it can be initialized far from the final edge and the adjustment of its parameters is easy and intuitive. In a second step, a parametric model composed of several cubic curves is fitted on the lips. This model is flexible enough to reproduce the specificities of very different lip shapes. Compared to existing models, it brings a significant accuracy and realism improvement.