iOS 使用lame庫將wav轉mp3
阿新 • • 發佈:2018-11-05
- (NSString *)audioPCMtoMP3:(NSString *)wavPath { NSString *cafFilePath = wavPath; NSString *mp3FilePath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).lastObject stringByAppendingPathComponent:@"ddd.mp3"]; NSFileManager* fileManager = [NSFileManager defaultManager]; if([fileManager removeItemAtPath:mp3FilePath error:nil]){ NSLog(@"刪除原MP3檔案"); } @try { int read, write; FILE *pcm = fopen([cafFilePath cStringUsingEncoding:1], "rb"); //source 被轉換的音訊檔案位置 fseek(pcm, 4*1024, SEEK_CUR); //skip file header FILE *mp3 = fopen([mp3FilePath cStringUsingEncoding:1], "wb"); //output 輸出生成的Mp3檔案位置 const int PCM_SIZE = 8192; const int MP3_SIZE = 8192; short int pcm_buffer[PCM_SIZE*2]; unsigned char mp3_buffer[MP3_SIZE]; lame_t lame = lame_init(); // lame_set_in_samplerate(lame, 22050.0); lame_set_in_samplerate(lame, 4000.0); lame_set_VBR(lame, vbr_default); lame_init_params(lame); do { read = fread(pcm_buffer, 2*sizeof(short int), PCM_SIZE, pcm); if (read == 0) write = lame_encode_flush(lame, mp3_buffer, MP3_SIZE); else write = lame_encode_buffer_interleaved(lame, pcm_buffer, read, mp3_buffer, MP3_SIZE); fwrite(mp3_buffer, write, 1, mp3); }while (read != 0); lame_close(lame); fclose(mp3); fclose(pcm); } @catch (NSException *exception) { NSLog(@"%@",[exception description]); } @finally { return mp3FilePath; } }
這裡邊的取樣率可以更改的,也就是那個4000