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Running Pulseaudio on Qt



  • Hi I am running pulse audio playback example mentioned in the wesite on qt.
    I am getting a blank nise intead of the audio playing.
    I tried with formats mp3 and ogg.both are resulting the same.
    I am pasting the code below
    @#include <QtGui/QApplication>
    #include "qmlapplicationviewer.h"
    #ifdef HAVE_CONFIG_H
    #include <config.h>
    #endif

    #include <stdio.h>
    #include <unistd.h>
    #include <string.h>
    #include <errno.h>
    #include <fcntl.h>

    #include <pulse/simple.h>
    #include <pulse/error.h>
    #include <pulse/gccmacro.h>
    #include <pulse/pulseaudio.h>
    #include <pulse/sample.h>
    #include <fstream>
    using namespace std;

    #define BUFSIZE 1024

    int main(int argc, char *argv[])
    {

    QApplication app(argc, argv);
    
    QmlApplicationViewer viewer;
    viewer.setOrientation(QmlApplicationViewer::ScreenOrientationAuto);
    viewer.setMainQmlFile&#40;QLatin1String("qml/paudio/main.qml"&#41;);
    viewer.showExpanded();
    //ofstream myfile;
     // myfile.open ("abc.mp3");
    
    
    
    static  pa_sample_spec ss;
    
    
        ss.format = PA_SAMPLE_S16LE;
       ss.rate = 44100;
        ss.channels = 2;
    
    
    
    
    
       pa_simple *s = NULL;
       int ret = 1;
       int error;
    
       /* replace STDIN with the specified file if needed */
       if (argc >= 1) {
           int fd;
           argv[1]="abc.ogg";
    
           if ((fd = open(argv[1], O_RDONLY)) < 0) {
               fprintf(stderr, __FILE__": open() failed: %s\n", strerror(errno));
               goto finish;
           }
    
           if (dup2(fd, STDIN_FILENO) < 0) {
               fprintf(stderr, __FILE__": dup2() failed: %s\n", strerror(errno));
               goto finish;
           }
    
         //  close(fd);
       }
    
       /* Create a new playback stream */
       if (!(s = pa_simple_new(NULL, argv[0], PA_STREAM_PLAYBACK, NULL, "sru123", &ss, NULL, NULL, &error))) {
           fprintf(stderr, __FILE__": pa_simple_new() failed: %s\n", pa_strerror(error));
           goto finish;
       }
    
       for (;;) {
           uint8_t buf[BUFSIZE];
           ssize_t r;
    

    #if 0
    pa_usec_t latency;

           if ((latency = pa_simple_get_latency(s, &error)) == (pa_usec_t) -1) {
               fprintf(stderr, __FILE__": pa_simple_get_latency() failed: %s\n", pa_strerror(error));
               goto finish;
           }
    
           fprintf(stderr, "%0.0f usec    \r", (float)latency);
    

    #endif

           /* Read some data ... */
           if ((r = read(STDIN_FILENO, buf, sizeof(buf))) <= 0) {
               if (r == 0) /* EOF */
                   break;
    
               fprintf(stderr, __FILE__": read() failed: %s\n", strerror(errno));
               goto finish;
           }
    
           /* ... and play it */
           if (pa_simple_write(s, buf, (size_t) r, &error) < 0) {
               fprintf(stderr, __FILE__": pa_simple_write() failed: %s\n", pa_strerror(error));
               goto finish;
           }
       }
    
       /* Make sure that every single sample was played */
       if (pa_simple_drain(s, &error) < 0) {
           fprintf(stderr, __FILE__": pa_simple_drain() failed: %s\n", pa_strerror(error));
           goto finish;
       }
    
       ret = 0;
    

    finish:

       if (s)
           pa_simple_free(s);
    
       //return ret;
    

    return app.exec();
    }
    @
    I am new to Linux and pulse audio. so please explain in detail.


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