• Title/Summary/Keyword: Input preprocessing

Search Result 295, Processing Time 0.046 seconds

Preprocessing method for enhancing digital audio quality in speech communication system (음성통신망에서 디지털 오디오 신호 음질개선을 위한 전처리방법)

  • Song Geun-Bae;Ahn Chul-Yong;Kim Jae-Bum;Park Ho-Chong;Kim Austin
    • Journal of Broadcast Engineering
    • /
    • v.11 no.2 s.31
    • /
    • pp.200-206
    • /
    • 2006
  • This paper presents a preprocessing method to modify the input audio signals of a speech coder to obtain the finally enhanced signals at the decoder. For the purpose, we introduce the noise suppression (NS) scheme and the adaptive gain control (AGC) where an audio input and its coding error are considered as a noisy signal and a noise, respectively. The coding error is suppressed from the input and then the suppressed input is level aligned to the original input by the following AGC operation. Consequently, this preprocessing method makes the spectral energy of the music input redistributed all over the spectral domain so that the preprocessed music can be coded more effectively by the following coder. As an artifact, this procedure needs an additional encoding pass to calculate the coding error. However, it provides a generalized formulation applicable to a lot of existing speech coders. By preference listening tests, it was indicated that the proposed approach produces significant enhancements in the perceived music qualities.

Preprocessing Technique for Improving Action Recognition Performance in ERP Video with Multiple Objects (다중 객체가 존재하는 ERP 영상에서 행동 인식 모델 성능 향상을 위한 전처리 기법)

  • Park, Eun-Soo;Kim, Seunghwan;Ryu, Eun-Seok
    • Journal of Broadcast Engineering
    • /
    • v.25 no.3
    • /
    • pp.374-385
    • /
    • 2020
  • In this paper, we propose a preprocessing technique to solve the problems of action recognition with Equirectangular Projection (ERP) video. The preprocessing technique proposed in this paper assumes the person object as the subject of action, that is, the Object of Interest (OOI), and the surrounding area of the OOI as the ROI. The preprocessing technique consists of three modules. I) Recognize person object in the image with object recognition model. II) Create a saliency map from the input image. III) Select subject of action using recognized person object and saliency map. The subject boundary box of the selected action is input to the action recognition model in order to improve the action recognition performance. When comparing the performance of the proposed preprocessing method to the action recognition model and the performance of the original ERP image input method, the performance is improved up to 99.6%, and the action is obtained when only the OOI is detected. It can also see the effects of related video summaries.

Preprocessing in large scale linear programming problems (대형선형계획문제의 사전처리)

  • 성명기;박순달
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 1996.10a
    • /
    • pp.285-288
    • /
    • 1996
  • Generally MPS, standardized by IBM, is the input type of large scale linear programming problems, and there may be unnecessary variables or constraints. These can be discarded by preprocessing. As the size of a problem is reduced by preprocessing, the running time is reduced. And more, the infeasibility of a problem may be detected before using solution methods. When the preprocessing implemented by this paper is used in NETLIB problems, it removes unnecessary variables and constraints by 21%, 15%, respectively. The use of preprocessing gives in the average 21% reduction in running time by applying the interior point method. Preprocessing can detect 10 out of 30 infeasible NETLIB problems.

  • PDF

Design of a real-time image preprocessing system with linescan camera interface (라인스캔 카메라 인터페이스를 갖는 실시간 영상 전처리 시스템의 설계)

  • Lyou, Kyeong;Kim, Kyeong-Min;Park, Gwi-Tae
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.3 no.6
    • /
    • pp.626-631
    • /
    • 1997
  • This paper represents the design of a real-time image preprocessing system. The preprocessing system performs hardware-wise mask operations and thresholding operations at the speed of camera output single rate. The preprocessing system consists of the preprocessing board and the main processing board. The preprocessing board includes preprocessing unit that includes a $5\times5$ mask processor and LUT, and can perform mask and threshold operations in real-time. To achieve high-resolution image input data($20485\timesn$), the preprocessing board has a linescan camera interface. The main processing board includes the image processor unit and main processor unit. The image processor unit is equipped with TI's TMS320C32 DSP and can perform image processing algorithms at high speed. The main processor unit controls the operation of total system. The proposed system is faster than the conventional CPU based system.

  • PDF

Prediction of the price for stock index futures using integrated artificial intelligence techniques with categorical preprocessing

  • Kim, Kyoung-jae;Han, Ingoo
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 1997.10a
    • /
    • pp.105-108
    • /
    • 1997
  • Previous studies in stock market predictions using artificial intelligence techniques such as artificial neural networks and case-based reasoning, have focused mainly on spot market prediction. Korea launched trading in index futures market (KOSPI 200) on May 3, 1996, then more people became attracted to this market. Thus, this research intends to predict the daily up/down fluctuant direction of the price for KOSPI 200 index futures to meet this recent surge of interest. The forecasting methodologies employed in this research are the integration of genetic algorithm and artificial neural network (GAANN) and the integration of genetic algorithm and case-based reasoning (GACBR). Genetic algorithm was mainly used to select relevant input variables. This study adopts the categorical data preprocessing based on expert's knowledge as well as traditional data preprocessing. The experimental results of each forecasting method with each data preprocessing method are compared and statistically tested. Artificial neural network and case-based reasoning methods with best performance are integrated. Out-of-the Model Integration and In-Model Integration are presented as the integration methodology. The research outcomes are as follows; First, genetic algorithms are useful and effective method to select input variables for Al techniques. Second, the results of the experiment with categorical data preprocessing significantly outperform that with traditional data preprocessing in forecasting up/down fluctuant direction of index futures price. Third, the integration of genetic algorithm and case-based reasoning (GACBR) outperforms the integration of genetic algorithm and artificial neural network (GAANN). Forth, the integration of genetic algorithm, case-based reasoning and artificial neural network (GAANN-GACBR, GACBRNN and GANNCBR) provide worse results than GACBR.

  • PDF

A Facial Expression Recognition Method Using Two-Stream Convolutional Networks in Natural Scenes

  • Zhao, Lixin
    • Journal of Information Processing Systems
    • /
    • v.17 no.2
    • /
    • pp.399-410
    • /
    • 2021
  • Aiming at the problem that complex external variables in natural scenes have a greater impact on facial expression recognition results, a facial expression recognition method based on two-stream convolutional neural network is proposed. The model introduces exponentially enhanced shared input weights before each level of convolution input, and uses soft attention mechanism modules on the space-time features of the combination of static and dynamic streams. This enables the network to autonomously find areas that are more relevant to the expression category and pay more attention to these areas. Through these means, the information of irrelevant interference areas is suppressed. In order to solve the problem of poor local robustness caused by lighting and expression changes, this paper also performs lighting preprocessing with the lighting preprocessing chain algorithm to eliminate most of the lighting effects. Experimental results on AFEW6.0 and Multi-PIE datasets show that the recognition rates of this method are 95.05% and 61.40%, respectively, which are better than other comparison methods.

Design of Multiple Model Fuzzy Predictors using Data Preprocessing and its Application (데이터 전처리를 이용한 다중 모델 퍼지 예측기의 설계 및 응용)

  • Bang, Young-Keun;Lee, Chul-Heui
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.58 no.1
    • /
    • pp.173-180
    • /
    • 2009
  • It is difficult to predict non-stationary or chaotic time series which includes the drift and/or the non-linearity as well as uncertainty. To solve it, we propose an effective prediction method which adopts data preprocessing and multiple model TS fuzzy predictors combined with model selection mechanism. In data preprocessing procedure, the candidates of the optimal difference interval are determined based on the correlation analysis, and corresponding difference data sets are generated in order to use them as predictor input instead of the original ones because the difference data can stabilize the statistical characteristics of those time series and better reveals their implicit properties. Then, TS fuzzy predictors are constructed for multiple model bank, where k-means clustering algorithm is used for fuzzy partition of input space, and the least squares method is applied to parameter identification of fuzzy rules. Among the predictors in the model bank, the one which best minimizes the performance index is selected, and it is used for prediction thereafter. Finally, the error compensation procedure based on correlation analysis is added to improve the prediction accuracy. Some computer simulations are performed to verify the effectiveness of the proposed method.

A Preprocessing Algorithm for Efficient Lossless Compression of Gray Scale Images

  • Kim, Sun-Ja;Hwang, Doh-Yeun;Yoo, Gi-Hyoung;You, Kang-Soo;Kwak, Hoon-Sung
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.2485-2489
    • /
    • 2005
  • This paper introduces a new preprocessing scheme to replace original data of gray scale images with particular ordered data so that performance of lossless compression can be improved more efficiently. As a kind of preprocessing technique to maximize performance of entropy encoder, the proposed method converts the input image data into more compressible form. Before encoding a stream of the input image, the proposed preprocessor counts co-occurrence frequencies for neighboring pixel pairs. Then, it replaces each pair of adjacent gray values with particular ordered numbers based on the investigated co-occurrence frequencies. When compressing ordered image using entropy encoder, we can expect to raise compression rate more highly because of enhanced statistical feature of the input image. In this paper, we show that lossless compression rate increased by up to 37.85% when comparing results from compressing preprocessed and non-preprocessed image data using entropy encoder such as Huffman, Arithmetic encoder.

  • PDF

A Study on a Analysis and Comparison of Preprocessing Technique for the Speech Compression (음성압축을 위한 전처리기법의 비교 분석에 관한 연구)

  • Jang, Kyung-A;Min, So-Yeon;Bae, Myung-Jin
    • Speech Sciences
    • /
    • v.10 no.4
    • /
    • pp.125-136
    • /
    • 2003
  • Speech coding techniques have been studied to reduce the complexity and bit rate but also to improve the sound quality. CELP type vocoder, has used as a one of standard, supports the great sound quality even low bit rate. In this paper, the preprocessing of input speech to reduce the bit rate is the different with the conventional vocoder. The different kinds of parameter are used for the preprocessing so this paper is compared with theses parameters for finding the more appropriate parameter for the vocoder. The parameters are used to synthesize the speech not to encode or decode for coding technique so we proposed the simple algorithm not to have the influence on the processing time or the computation time. The parameters in used the preprocessing step are speaking rate, duration and PSOLA technique.

  • PDF

A Study on Optical Condition and preprocessing for Input Image Improvement of Dented and Raised Characters of Tires (타이어 음,양각 문자의 입력영상 개선을 위한 전처리와 광학조건에 관한 연구)

  • 류한성;최중경;구본민;박무열;윤경섭
    • Proceedings of the IEEK Conference
    • /
    • 2001.06d
    • /
    • pp.93-96
    • /
    • 2001
  • In this paper, we present a vision algorithm and method for input image improvement and preprocessing of dented and raised characters on the sidewall of tires. we define optical condition between reflect coefficient and reflectance by the physical vector calculate. On the contrary this work will recognize the engraved characters using the computer vision technique. Tire input images have all most same grey levels between the characters and backgrounds. The reflectance is little from a tire surface. therefore, it's very difficult segment the characters from the background. Moreover, one side of the character string is raised and the other is dented. So, the captured images are varied with the angle of camera and illumination. For optimum input images, the angle between camera and illumination was found out to be with in 90。 .In addition, We used complex filtering with low-pass and high-pass band filters to improve input images, for clear input images. Finally we define equation reflect coefficient and reflectance. By doing this, we obtained good images of tires for pattern recognition.

  • PDF