/* various PCM "codecs" */
CODEC_ID_PCM_S16LE= 0x10000,
CODEC_ID_PCM_S16BE,
CODEC_ID_PCM_U16LE,
CODEC_ID_PCM_U16BE,
CODEC_ID_PCM_S8,
CODEC_ID_PCM_U8,
CODEC_ID_PCM_MULAW,
CODEC_ID_PCM_ALAW,
CODEC_ID_PCM_S32LE,
CODEC_ID_PCM_S32BE,
CODEC_ID_PCM_U32LE,
CODEC_ID_PCM_U32BE,
CODEC_ID_PCM_S24LE,
CODEC_ID_PCM_S24BE,
CODEC_ID_PCM_U24LE,
CODEC_ID_PCM_U24BE,
CODEC_ID_PCM_S24DAUD,
CODEC_ID_PCM_ZORK,
CODEC_ID_PCM_S16LE_PLANAR,
CODEC_ID_PCM_DVD,
CODEC_ID_PCM_F32BE,
CODEC_ID_PCM_F32LE,
CODEC_ID_PCM_F64BE,
CODEC_ID_PCM_F64LE,
CODEC_ID_PCM_BLURAY,
CODEC_ID_PCM_LXF,
CODEC_ID_S302M,
/* various ADPCM codecs */
CODEC_ID_ADPCM_IMA_QT= 0x11000,
CODEC_ID_ADPCM_IMA_WAV,
CODEC_ID_ADPCM_IMA_DK3,
CODEC_ID_ADPCM_IMA_DK4,
CODEC_ID_ADPCM_IMA_WS,
CODEC_ID_ADPCM_IMA_SMJPEG,
CODEC_ID_ADPCM_MS,
CODEC_ID_ADPCM_4XM,
CODEC_ID_ADPCM_XA,
CODEC_ID_ADPCM_ADX,
CODEC_ID_ADPCM_EA,
CODEC_ID_ADPCM_G726,
CODEC_ID_ADPCM_CT,
CODEC_ID_ADPCM_SWF,
CODEC_ID_ADPCM_YAMAHA,
CODEC_ID_ADPCM_SBPRO_4,
CODEC_ID_ADPCM_SBPRO_3,
CODEC_ID_ADPCM_SBPRO_2,
CODEC_ID_ADPCM_THP,
CODEC_ID_ADPCM_IMA_AMV,
CODEC_ID_ADPCM_EA_R1,
CODEC_ID_ADPCM_EA_R3,
CODEC_ID_ADPCM_EA_R2,
CODEC_ID_ADPCM_IMA_EA_SEAD,
CODEC_ID_ADPCM_IMA_EA_EACS,
CODEC_ID_ADPCM_EA_XAS,
CODEC_ID_ADPCM_EA_MAXIS_XA,
CODEC_ID_ADPCM_IMA_ISS,
CODEC_ID_ADPCM_G722,

常用的应该只有U8,S16LE和S24LE，32bit的不知道默认是S32LE还是F32LE

5.1的wav用ffmpeg转成5.1的wav似乎只有编成pcm_s16是正常的,不知道是不是我编的ffmpeg不对,还是标准就对U8不支持,U8沙沙响,其他格式各种错误