alext.h：
#define AL_FORMAT_QUAD8 0x1204
101 #define AL_FORMAT_QUAD16 0x1205
102 #define AL_FORMAT_QUAD32 0x1206
103 #define AL_FORMAT_REAR8 0x1207
104 #define AL_FORMAT_REAR16 0x1208
105 #define AL_FORMAT_REAR32 0x1209
106 #define AL_FORMAT_51CHN8 0x120A
107 #define AL_FORMAT_51CHN16 0x120B
108 #define AL_FORMAT_51CHN32 0x120C
109 #define AL_FORMAT_61CHN8 0x120D
110 #define AL_FORMAT_61CHN16 0x120E
111 #define AL_FORMAT_61CHN32 0x120F
112 #define AL_FORMAT_71CHN8 0x1210
113 #define AL_FORMAT_71CHN16 0x1211
114 #define AL_FORMAT_71CHN32 0x1212 8声道32位深
al.h：
339 #define AL_FORMAT_MONO8 0x1100
340 #define AL_FORMAT_MONO16 0x1101
341 #define AL_FORMAT_STEREO8 0x1102
342 #define AL_FORMAT_STEREO16 0x1103
不同的选项：Block alignment不同。否则没法采集