Development Of Heart Sound Diagnosis System Based On Android Platform

The high incidence of cardiovascular disease has aroused widespread concern in Society.The changes of heart sound and heart rate are the earliest features of cardiac disease normally.Traditionally,the method of cardiac disease examination is going to the hospital regularly,then the doctor use stethoscope to obtain the heart sound of patients.It spends lots of time and energy.The popularity of network communication technology promotes the development of telemedicine.This paper describes a diagnosis system of heart sound which achieves telemedicine based on the research of heart sounds,the users are capable of checking their cardiac health staying at home.The main contents include:1)The development of electronic stethoscope.The electronic stethoscope includes cavity structures and one filter amplifier circuit mainly.It's used to collect the weak heart sound,then amplify heart sound and filter the noise being brought when stethoscope collects the heart sound at the same time.2)This paper implements abnormal heart sound recognition algorithm based on LZ complexity.Firstly,it introduces short-time energy and short-time zero crossing rate to achieve the endpoints detection of heart sound,extracts each subsection of heart sound cycle.Then we separates the cycle to the first heart sound,the systole heart sound,the second heart sound with the addition of diastole heart sound.Finally,it computes LZ complexity of each segment of the signal,determines whether the heart sound is abnormal according to the classification results based on LZ complexity of normal and abnormal heart sounds.3)This paper designs a compression system based on the discrete cosine transform.It makes heart sound compressed greatly to reduce network bandwidth and server load.In the paper,the performance of DCT is evaluated on objective and subjective aspects.The objective aspect is to analyze the SNR of compression system,the subjective aspect is to compare heart sound compressed before and after by several cardiologists.4)In addition,this paper develops an application based on Android platform.The application receives the heart sounds collected by electronic stethoscope firstly.Then it builds several function modules,includes heart sound display,playback,storage,abnormal heart sound recognition,compression,upload and download.Furthermore,it provides registered login function and service of personal information management.