输出格式: 3GP, 3GP (AAC), 3G2, 3G2 (AAC), AAC, AC3, AIFF, AMR, AU, AU (a-Law), AU (u-Law), FLAC, M4A, M4A (ALAC), MMF, MOV, MP2, MP3, MP4, OGG, OGG (FLAC), RA, RM, WAV, WAV (ADPCM IMA), WAV (ADPCM Microsoft), WAV (ADPCM Yamaha), WAV (GSM), WMA, PCM (Little-Endian), PCM (Big-Endian), PCM (a-Law), PCM (u-