Question

我试图读取RIFF文件的头文件。一切看起来都很好。但是当我编写并运行时，我读取的所有文件都具有相同的数据大小。我不知道为什么？我已经运行了一些关于读取RIFF文件的header_file的代码，但它并没有什么不同。

#include <iostream>
#include <fstream>
#include <cstdio>
#include <cstring>
#include <vector>
#include <stdint.h>
#include <cmath>

using namespace std;

#define SWAPPED_US(x) (((x) >> 8) | ((x) << 8))
#define SWAPPED_UL(x) ((((x) >> 24) & 0xff) | (((x) << 8) & 0xff0000) | (((x) >> 8) & 0xff00) | (((x) << 24) & 0xff000000))

#pragma pack(push, 1)
typedef struct {
    char ID [4];
    uint32_t Size;
    char Format [4];
    char SubID_1 [4];
    uint32_t SubSize_1;
    uint16_t AudioFmt;
    uint16_t Channel;
    uint32_t Frequency;
    uint32_t bytesRate;
    uint16_t BlockAlign;
    uint16_t BitsPerSample;
    char SubID_2 [4];
    uint32_t SubSize_2;
} RIFF_header;
#pragma pack(pop)

int getFileSize(FILE *inFile){
    int fileSize = 0;
    fseek(inFile,0,SEEK_END);
    fileSize=ftell(inFile);
    fseek(inFile,0,SEEK_SET);
    return fileSize;
}

int main ()
{
    FILE *fpoint;
    fpoint = fopen ("test.wav", "rb");
    RIFF_header *wave_file; wave_file = new RIFF_header;
    fread ((void*)wave_file, sizeof (RIFF_header), (size_t)1, fpoint); 


    wave_file->SubSize_2 = SWAPPED_UL(wave_file->SubSize_2); // I think it's big-endianess so we have to swap byte

    cout << "Size of file:      " << getFileSize(fpoint) << endl;
    cout << "Header:            " << wave_file->ID[0] 
                      << wave_file->ID[1] 
                      << wave_file->ID[2] 
                      << wave_file->ID[3] << endl;

    cout << "Format:            " << wave_file->Format[0] 
                      << wave_file->Format[1] 
                      << wave_file->Format[2] 
                      << wave_file->Format[3] << endl;

    cout << "Sub-chunk1 ID:         " << wave_file->SubID_1[0] 
                          << wave_file->SubID_1[1] 
                      << wave_file->SubID_1[2] 
                      << wave_file->SubID_1[3] << endl;

    cout << "Sub-chunk1 Size:   " << wave_file->SubSize_1 << endl;

    cout << "Audio Format:      " << wave_file->AudioFmt << endl;

    cout << "Channel:       " << wave_file->Channel << endl;

    cout << "Sample Rate:       " << wave_file->Frequency << endl;

    cout << "Byte Rate:         " << wave_file->bytesRate << endl;

    cout << "BlockAlign:        " << wave_file->BlockAlign << endl;

    cout << "Bits per sample:   " << wave_file->BitsPerSample << endl;

    cout << "Sub-chunk2 ID:         " << wave_file->SubID_2[0] 
                      << wave_file->SubID_2[1] 
                      << wave_file->SubID_2[2] 
                      << wave_file->SubID_2[3] << endl;
    cout << "Sub-chunk2 Size:   " << wave_file->SubSize_2 << endl;
    return 0;
}

Answer 1

检查你的SubSize_1 ...有时它是16个字节，有时是18个。如果你错了，你的SubSize_2也会出错......

读取WAVE文件的头文件

1 个答案: