ios – convertir .m4a en file .mp3 par programme

Ici, j'ai le format audio m4a, j'ai besoin de convertir en format mp3.

pour cela, j'ai utilisé le code comme

- (void) toMp3{ NSSsortingng *m4aFilePath = pathToSave; NSSsortingng *mp3FileName = [NSSsortingng ssortingngWithFormat:@"Audio%d",[audioArr count]]; mp3FileName = [mp3FileName ssortingngByAppendingSsortingng:@".mp3"]; pathToSave = [NSSsortingng ssortingngWithFormat:@"%@/%@", DOCUMENTS_FOLDER, mp3FileName]; NSLog(@"pathToSave :%@",pathToSave); @try { int read, write; FILE *pcm = fopen([cafFilePath cSsortingngUsingEncoding:1], "rb"); //source fseek(pcm, 4*1024, SEEK_CUR); //skip file header FILE *mp3 = fopen([pathToSave cSsortingngUsingEncoding:1], "wb"); //output 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, 44100); 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 { [self performSelectorOnMainThread:@selector(convertMp3Finish) withObject:nil waitUntilDone:YES]; } } 

Comment puis-je convertir de format M4A au format mp3. M'aider

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 @try { int read, write; FILE *pcm = fopen([cafFilePath cSsortingngUsingEncoding:1], "rb"); //source fseek(pcm, 4*1024, SEEK_CUR); //skip file header mp3 = fopen([mp3FilePath cSsortingngUsingEncoding:1], "wb"); //output const int PCM_SIZE = 8192*3; const int MP3_SIZE = 8192*3; short int pcm_buffer[PCM_SIZE*2]; unsigned char mp3_buffer[MP3_SIZE]; lame_t lame = lame_init(); lame_set_in_samplerate(lame, 11025*2); lame_set_VBR(lame, vbr_default); lame_init_params(lame); int nTotalRead=0; do { read = fread(pcm_buffer, 2*sizeof(short int), PCM_SIZE, pcm); nTotalRead+=read*4; 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); // write = lame_encode_buffer(lame, pcm_buffer,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]); }