[問題] wav adpcm格式
WAV檔的格式:
起始點 大小 輸出
-----------------------------------------------------------
0 4 bytes "RIFF"
4 4 bytes <File length - 8>
8 4 bytes "WAVE"
12 4 bytes "fmt "
16 4 bytes <Length of the fmt data> // (=16)
20 2 bytes <WAVE File Encoding Tag>
22 2 bytes <Channels> // Channels: 1 = mono, 2 = stereo
24 4 bytes <Sample rate> // Samples per second: e.g., 44100
28 4 bytes <bytes/second> // sample rate * block align
32 2 bytes <block align> // channels * bits/sample / 8
34 2 bytes <bits/sample> // 8 or 16
36 4 bytes "data"
40 4 bytes <Sample data size(n)>
44 (n)bytes <Sample data>
------------------------------------------------------------
所以我要讀位置22的 Channels
不是應該int Channels
fseek(f,0x22,SEEK_SET);
fread(&nChannels,2,1,f);
cout<< Cannels <<'\n';
然後就可以跑出我要的Channels數,但
正確的寫法卻是
fseek(f,0x16,SEEK_SET);
fread(&nChannels,2,1,f);
cout<< Cannels <<'\n';
我的疑問是:1.怎麼是0x16而不是0x22,
怎麼會差六個BYTE呢???
2.若要讀取sample data:
int data=0;
fseek(f,0x44,SEEK_SET);
fread(&data,2,1,f);
cout<< data <<'\n';
執行出來卻是 0 ??????
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※ 編輯: wowrz 來自: 114.37.18.48 (12/29 04:22)
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