wav文件解析

太过爱你忘了你带给我的痛 2022-09-09 09:46 207阅读 0赞

参考资料：  
https://www.cnblogs.com/guojun-junguo/p/10129548.html  
http://www.topherlee.com/software/pcm-tut-wavformat.html  
http://www-mmsp.ece.mcgill.ca/Documents/AudioFormats/WAVE/Samples.html  
https://datatracker.ietf.org/doc/html/draft-ema-vpim-wav-00.txt  
https://blog.ibaoger.com/2016/09/21/waveform-audio-file-format/

Wave文件包括Header和Data，其中Header结构如下：

The header of a WAV (RIFF) file is 44 bytes long and has the following format:

<table> 
 <thead> 
  <tr> 
   <th>Positions</th> 
   <th>Sample Value</th> 
   <th>Description</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>1 - 4</td> 
   <td>“RIFF”</td> 
   <td>Marks the file as a riff file. Characters are each 1 byte long.</td> 
  </tr> 
  <tr> 
   <td>5 - 8</td> 
   <td>File size (integer)</td> 
   <td>Size of the overall file - 8 bytes, in bytes (32-bit integer). Typically, you’d fill this in after creation.</td> 
  </tr> 
  <tr> 
   <td>9 -12</td> 
   <td>“WAVE”</td> 
   <td>File Type Header. For our purposes, it always equals “WAVE”.</td> 
  </tr> 
  <tr> 
   <td>13-16</td> 
   <td>"fmt "</td> 
   <td>Format chunk marker. Includes trailing null</td> 
  </tr> 
  <tr> 
   <td>17-20</td> 
   <td>16</td> 
   <td>Length of format data as listed above</td> 
  </tr> 
  <tr> 
   <td>21-22</td> 
   <td>1</td> 
   <td>Type of format (1 is PCM) - 2 byte integer</td> 
  </tr> 
  <tr> 
   <td>23-24</td> 
   <td>2</td> 
   <td>Number of Channels - 2 byte integer</td> 
  </tr> 
  <tr> 
   <td>25-28</td> 
   <td>44100</td> 
   <td>Sample Rate - 32 byte integer. Common values are 44100 (CD), 48000 (DAT). Sample Rate = Number of Samples per second, or Hertz.</td> 
  </tr> 
  <tr> 
   <td>29-32</td> 
   <td>176400</td> 
   <td>(Sample Rate * BitsPerSample * Channels) / 8.</td> 
  </tr> 
  <tr> 
   <td>33-34</td> 
   <td>4</td> 
   <td>(BitsPerSample * Channels) / 8.1 - 8 bit mono2 - 8 bit stereo/16 bit mono4 - 16 bit stereo</td> 
  </tr> 
  <tr> 
   <td>35-36</td> 
   <td>16</td> 
   <td>Bits per sample</td> 
  </tr> 
  <tr> 
   <td>37-40</td> 
   <td>“data”</td> 
   <td>“data” chunk header. Marks the beginning of the data section.</td> 
  </tr> 
  <tr> 
   <td>41-44</td> 
   <td>File size (data)</td> 
   <td>Size of the data section.</td> 
  </tr> 
 </tbody> 
</table>

Sample values are given above for a 16-bit stereo source.

具体结构体定义如下：

typedef struct WAV_RIFF { 
        /* chunk "riff" */
        char ChunkID[4];   /* "RIFF" */
        /* sub-chunk-size */
        uint32_t ChunkSize; /* 36 + Subchunk2Size */
        /* sub-chunk-data */
        char Format[4];    /* "WAVE" */
    } RIFF_t;
    
    typedef struct WAV_FMT { 
        /* sub-chunk "fmt" */
        char Subchunk1ID[4];   /* "fmt " */
        /* sub-chunk-size */
        uint32_t Subchunk1Size; /* 16 for PCM */
        /* sub-chunk-data */
        uint16_t AudioFormat;   /* PCM = 1*/
        uint16_t NumChannels;   /* Mono = 1, Stereo = 2, etc. */
        uint32_t SampleRate;    /* 8000, 44100, etc. */
        uint32_t ByteRate;  /* = SampleRate * NumChannels * BitsPerSample/8 */
        uint16_t BlockAlign;    /* = NumChannels * BitsPerSample/8 */
        uint16_t BitsPerSample; /* 8bits, 16bits, etc. */
    } FMT_t;
    
    typedef struct WAV_data { 
        /* sub-chunk "data" */
        char Subchunk2ID[4];   /* "data" */
        /* sub-chunk-size */
        uint32_t Subchunk2Size; /* data size */
        /* sub-chunk-data */
    // Data_block_t block;
    } Data_t;
    
    typedef struct WAV_fotmat { 
       RIFF_t riff;
       FMT_t fmt;
       Data_t data;
    } Wav;

一个标准的wave文件header示例：

const Wav wav = { 
    		{ 
    				"RIFF",	//RIFF marker
    				9356,	//file-size (equals file-size - 8)
    				"WAVE",	//Mark it as type "WAVE"
    		},
    		{ 
    				"fmt",	//Mark the format section.
    				16,		//Length of format data. Always 16
    				1,		//Wave type PCM
    				1,		//1 channel(or 2 channels)
    				44100,	//44.1 kHz Sample Rate (CD-Quality)
    				88200,	//(Sample Rate * Bit Size * Channels) / 8
    				2,		//(Bit Size * Channels) / 8
    				16,		//Bits per sample (=Bit Size * Samples)
    		},
    		{ 
    				"data",	//"data" marker
    				9320,	//data-size (equals file-size - 44).
    		}
    };

将wave文件数据保存在头文件中：

#include <stdio.h>
    #include <stdlib.h>
    #include <unistd.h>
    #include <stdint.h>
    #include <unistd.h>
    #include <string.h>
    #include <stdbool.h>
    #include <gulliver.h>
    #include <sys/stat.h>
     
    #define u8 unsigned char
    #define u16 unsigned short
    #define u32 unsigned long
     
     
    #define FILE_SCALE	8 	//音频文件质量 8或16 
     
    //44字节 
    typedef struct { 
    	u8 riff_mark[4];		//
    	u32 file_size;
    	u8	wave_str[4];
    	u8	fmt_str[4];
    	u32 pcm_bit_num;
    	u16 pcm_encode;
    	u16 sound_channel;
    	u32 pcm_sample_freq;
    	u32 byte_freq;
    	u16 block_alin;
    	u16 sample_bits;
    	u8	data_str[4]; 
    	u32 sound_size;
    } WAV_Typedef;
     
    WAV_Typedef WAVFile_Array;
     
    u16 *Sound_Data; 
     
    u8 *Read_Sound_Data;
    
     
     /* wave head */
     struct RIFF_CHUNK
    { 
        char riffid[4];
        int32_t dwSize;
        char riffType[4];
    };
    typedef struct RIFF_CHUNK WAVE_HEADER;
    
    struct FORMAT_CHUNK
    { 
        char fccid[4];
        int32_t dwSize;
        short wFormatTag;
        short wChannels;
        int32_t dwSamplesPerSec;
        int32_t dwAvgBytePerSec;
        short wBlockAlign;
        short uiBitsPerSample;
    };
    typedef struct FORMAT_CHUNK WAVE_FORMAT;
    
    struct DATA_CHUNK
    { 
        char fccid[4];
        int32_t dwSize;
    };
    typedef struct DATA_CHUNK WAVE_DATA;
    
    char *mWaveDataBuffer;
     
     
     typedef struct WAV_RIFF { 
        /* chunk "riff" */
        char ChunkID[4];   /* "RIFF" */
        /* sub-chunk-size */
        uint32_t ChunkSize; /* 36 + Subchunk2Size */
        /* sub-chunk-data */
        char Format[4];    /* "WAVE" */
    } RIFF_t;
    
    typedef struct WAV_FMT { 
        /* sub-chunk "fmt" */
        char Subchunk1ID[4];   /* "fmt " */
        /* sub-chunk-size */
        uint32_t Subchunk1Size; /* 16 for PCM */
        /* sub-chunk-data */
        uint16_t AudioFormat;   /* PCM = 1*/
        uint16_t NumChannels;   /* Mono = 1, Stereo = 2, etc. */
        uint32_t SampleRate;    /* 8000, 44100, etc. */
        uint32_t ByteRate;  /* = SampleRate * NumChannels * BitsPerSample/8 */
        uint16_t BlockAlign;    /* = NumChannels * BitsPerSample/8 */
        uint16_t BitsPerSample; /* 8bits, 16bits, etc. */
    } FMT_t;
    
    typedef struct WAV_data { 
        /* sub-chunk "data" */
        char Subchunk2ID[4];   /* "data" */
        /* sub-chunk-size */
        uint32_t Subchunk2Size; /* data size */
        /* sub-chunk-data */
    // Data_block_t block;
    } Data_t;
    
    //typedef struct WAV_data_block { 
    //} Data_block_t;
    
    typedef struct WAV_fotmat { 
       RIFF_t riff;
       FMT_t fmt;
       Data_t data;
    } Wav;
     
     
    int main()
    { 
    	FILE *fp,*fw;
    	int ret;
    	int i;
    	int numOfword;
    	
    	WAVE_HEADER WaveHeader;
        WAVE_FORMAT WaveFormat;
        WAVE_DATA WaveData;
    	
    	Wav wav;
        RIFF_t riff;
        FMT_t fmt;
        Data_t data;
    	
    	if((fp=fopen("/fs/mmc2/touch1.wav","rb"))==NULL)	//打开操作不成功
    		return 1;
    	if((fw=fopen("/fs/mmc2/wav_out.h","w"))==NULL)	//打开操作不成功
    		return 1;			
    	
    	/* fread(&wav, 1, sizeof(wav), fp); riff = wav.riff; fmt = wav.fmt; data = wav.data; printf("ChunkID \t%c%c%c%c\n", riff.ChunkID[0], riff.ChunkID[1], riff.ChunkID[2], riff.ChunkID[3]); printf("ChunkSize \t%d\n", riff.ChunkSize); printf("Format \t\t%c%c%c%c\n", riff.Format[0], riff.Format[1], riff.Format[2], riff.Format[3]); printf("\n"); printf("Subchunk1ID \t%c%c%c%c\n", fmt.Subchunk1ID[0], fmt.Subchunk1ID[1], fmt.Subchunk1ID[2], fmt.Subchunk1ID[3]); printf("Subchunk1Size \t%d\n", fmt.Subchunk1Size); printf("AudioFormat \t%d\n", fmt.AudioFormat); printf("NumChannels \t%d\n", fmt.NumChannels); printf("SampleRate \t%d\n", fmt.SampleRate); printf("ByteRate \t%d\n", fmt.ByteRate); printf("BlockAlign \t%d\n", fmt.BlockAlign); printf("BitsPerSample \t%d\n", fmt.BitsPerSample); printf("\n"); printf("blockID \t%c%c%c%c\n", data.Subchunk2ID[0], data.Subchunk2ID[1], data.Subchunk2ID[2], data.Subchunk2ID[3]); printf("blockSize \t%d\n", data.Subchunk2Size); printf("\n"); printf("duration \t%d\n", data.Subchunk2Size / fmt.ByteRate); */
    	
    	
    	
    	printf("sizeof(WaveHeader)=%d\n",sizeof(WaveHeader));
    	printf("sizeof(WaveFormat)=%d\n",sizeof(WaveFormat));
    	printf("sizeof(WaveData)=%d\n",sizeof(WaveData));
    	
    	if(fread(&WaveHeader,sizeof(WaveHeader),1,fp)==1)
    		printf("WaveHeader read ok!\n");
    	
    	if(fread(&WaveFormat,sizeof(WaveFormat),1,fp)==1)
    		printf("WaveFormat read ok!\n");
    	
    	if(fread(&WaveData,sizeof(WaveData),1,fp)==1)
    		printf("WaveData read ok!\n");
    	
    	
    	printf("资源交换文件标志: %.4s\n",WaveHeader.riffid);
    	printf("文件大小: %d\n",WaveHeader.dwSize);
    	printf("文件格式: %.4s\n",WaveHeader.riffType);
    	
    	printf("波形格式: %.4s\n",WaveFormat.fccid);
    	printf("PCM: %dbits\n",WaveFormat.dwSize);
    	printf("声道: %s\n",WaveFormat.wChannels==1?"单声道":"双声道");
    	printf("采样速率: %d\n",WaveFormat.dwSamplesPerSec);
    	printf("码率: %d Bps\n",WaveFormat.dwAvgBytePerSec);
    	printf("块对齐: %d\n",WaveFormat.wBlockAlign);
    	printf("采样位宽: %d\n",WaveFormat.uiBitsPerSample);	
    	
    	printf("Data标志: %.4s\n",WaveData.fccid);	
    	printf("声音数据大小: %d\n",WaveData.dwSize);
    	
    
    	mWaveDataBuffer = malloc(WaveData.dwSize);
    	numOfword = fread(mWaveDataBuffer,sizeof(char),WaveData.dwSize/sizeof(char),fp);
    
    	printf("WaveData.dwSize/sizeof(short): %d\n",WaveData.dwSize/sizeof(char));
    	printf("numOfword: %d\n",numOfword);
    	
    	//fwrite(&WaveHeader,sizeof(WAVE_HEADER),1,fw);
        //fwrite(&WaveFormat,sizeof(WAVE_FORMAT),1,fw);
        //fwrite(&WaveData,sizeof(WAVE_DATA),1,fw);
    	//fwrite(mWaveDataBuffer,sizeof(short),numOfword,fw);
    
    	
    	{ 
    		int idx=0;
    		int line_count=0;
    		
    		fprintf(fw,"#ifndef __SOUND_DATA_H__\n");
    		fprintf(fw,"#define __SOUND_DATA_H__\n\n");
    		
    		
    		fprintf(fw,"#define SOUND_LENGTH\t%d\n\n",WaveData.dwSize);
    		fprintf(fw,"const unsigned char WAVE_DATA[SOUND_LENGTH] = {\n\t");
    		
    		for(i = 0;i < WaveData.dwSize/sizeof(char); i++)
    		{ 
    
    			fprintf(fw,"%02x, ",(mWaveDataBuffer[idx] & 0xff));
    			idx++;
    			line_count++;
    			if(line_count>8-1)
    			{ 
    				line_count=0;
    				fprintf(fw,"\n\t");
    			}
    		}
    		
    		fprintf(fw,"\n};\n#endif\n");
    		
    		
    		printf("\n ***** 已转换成头文件 wav_out.h *****\n"); 
    	}
    
    
    	if(mWaveDataBuffer){ 
    		free(mWaveDataBuffer);
    		mWaveDataBuffer = NULL;
    	}
    	
    	
    	if(fp!=NULL)
    		fclose(fp);	
    	if(fw!=NULL)
    		fclose(fw);	
    	
    	
    	return 0;	
    }