How to get Beats per minutes of a song in objective-c

Question

I did lots of R&D but did not get any good answer. I am working on music type app in iphone and i have to categorized songs on the basis of beats per minute.So my first task

Answer 1

Get Bpm of audio songs within minute:

BASS_SetConfig(BASS_CONFIG_IOS_MIXAUDIO, 0); // Disable mixing. To be called before BASS_Init.

if (HIWORD(BASS_GetVersion()) != BASSVERSION) {
    NSLog(@"An incorrect version of BASS was loaded");
}

// Initialize default device.
if (!BASS_Init(-1, 44100, 0, NULL, NULL)) {
    NSLog(@"Can't initialize device");

}

//NSArray *array = [NSArray arrayWithObject:@""

NSString *respath = [[NSBundle mainBundle] pathForResource:@"[Songs.PK] Paathshaala - 01 - Aye Khuda" ofType:@"mp3"];

DWORD chan1;
if(!(chan1=BASS_StreamCreateFile(FALSE, [respath UTF8String], 0, 0, BASS_SAMPLE_LOOP))) {
    NSLog(@"Can't load stream!");

}

mainStream=BASS_StreamCreateFile(FALSE, [respath cStringUsingEncoding:NSUTF8StringEncoding], 0, 0, BASS_SAMPLE_FLOAT|BASS_STREAM_PRESCAN|BASS_STREAM_DECODE);

float playBackDuration=BASS_ChannelBytes2Seconds(mainStream, BASS_ChannelGetLength(mainStream, BASS_POS_BYTE));
NSLog(@"Play back duration is %f",playBackDuration);
HSTREAM bpmStream=BASS_StreamCreateFile(FALSE, [respath UTF8String], 0, 0, BASS_STREAM_PRESCAN|BASS_SAMPLE_FLOAT|BASS_STREAM_DECODE);
//BASS_ChannelPlay(bpmStream,FALSE);
BpmValue= BASS_FX_BPM_DecodeGet(bpmStream,0.0,
                                 playBackDuration,
                                 MAKELONG(45,256),
                                 BASS_FX_BPM_MULT2,
                                NULL);
NSLog(@"BPM is %f",BpmValue);