I am developing an extremely simple audio player. It uses Gtk and portaudio/libsndfile. I've created a simple test interface with few buttons like Browse, Play etc. My player picks filename correctly, and after pressing Play it starts playing. But everything waits for playback to be finished. Nothing is active and I wonder how to stop it before it finishes by itself.
My code for Gtk is:
#include <stdio.h>
#include <gtk\gtk.h>
static GtkWidget *window;
const char *filename;
static void play_file (GtkButton *button, gpointer data)
{
sndFile_play(filename);
}
static gboolean delete_event( GtkWidget *widget,
GdkEvent *event,
gpointer data )
{
return FALSE;
}
static void destroy( GtkWidget *widget,
gpointer data )
{
gtk_main_quit ();
}
int main( int argc,
char *argv[] )
{
GtkWidget *button;
GtkWidget *box1;
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "MyPlayer");
g_signal_connect (window, "delete-event",
G_CALLBACK (delete_event), NULL);
g_signal_connect (window, "destroy",
G_CALLBACK (destroy), NULL);
gtk_container_set_border_width (GTK_CONTAINER (window), 20);
box1 = gtk_hbox_new (FALSE, 0);
gtk_container_add (GTK_CONTAINER (window), box1);
button = gtk_button_new_with_label ("Browse...");
g_signal_connect (button, "clicked",
G_CALLBACK (browse_clicked), NULL); //not given here
gtk_box_pack_start (GTK_BOX(box1), button, TRUE, TRUE, 0);
gtk_widget_show (button);
button = gtk_button_new_with_label ("Play");
g_signal_connect (button, "clicked",
G_CALLBACK (play_file), NULL);
gtk_box_pack_start (GTK_BOX(box1), button, TRUE, TRUE, 0);
gtk_widget_show (button);
gtk_widget_show (box1);
gtk_widget_show (window);
gtk_main ();
return 0;
}
If it is necessary I give my code for playing sound:
#include <stdio.h>
#include <stdlib.h>
#include <portaudio.h>
#include <sndfile.h>
#define FRAMES_PER_BUFFER (1024)
#define PA_SAMPLE_TYPE paInt16
typedef short SAMPLE;
#define BUFFER_LEN 128
#define MAX_CHANNELS 2
int sndFile_play (const char *infilename){
PaStreamParameters outputParameters;
PaStream *stream;
PaError err;
static short data[BUFFER_LEN];
SNDFILE *infile;
SF_INFO sfinfo;
sf_count_t readcount;
int channels;
int srate;
err = Pa_Initialize();
if ( !( infile = sf_open( infilename, SFM_READ, &sfinfo ) ) ) {
printf ("Not able to open input file %s.\n", infilename);
puts (sf_strerror (NULL));
return 1;
}
if ( sfinfo.channels > MAX_CHANNELS ){
printf ("Not able to process more than %d channels\n", MAX_CHANNELS);
return 1;
}
/* FILE INFO */
channels = sfinfo.channels; // убрать channels
printf("number of channels %d\n", sfinfo.channels);
srate = sfinfo.samplerate; //убрать
printf("sample rate %d\n", sfinfo.samplerate);
outputParameters.device = Pa_GetDefaultOutputDevice();
outputParameters.channelCount = sfinfo.channels;
outputParameters.sampleFormat = PA_SAMPLE_TYPE;
outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
outputParameters.hostApiSpecificStreamInfo = NULL;
printf("Begin playback.....\n"); fflush(stdout);
err = Pa_OpenStream(
&stream,
NULL,
&outputParameters,
sfinfo.samplerate,
FRAMES_PER_BUFFER,
paClipOff,
NULL,
NULL );
if( stream ) {
err = Pa_StartStream( stream );
printf("Waiting for playback to finish....\n"); fflush(stdout);
while ( ( readcount = sf_read_short( infile, data, BUFFER_LEN*sfinfo.channels ) ) ){
err = Pa_WriteStream( stream, data, BUFFER_LEN );
}
err = Pa_CloseStream( stream );
printf("Done.\n"); fflush(stdout);
}
sf_close( infile );
Pa_Terminate();
return 0;
}