linux声卡设备dsp设置音量,linux下音频设备DSP

最新推荐文章于 2022-10-29 23:37:56 发布

yinming9999999

最新推荐文章于 2022-10-29 23:37:56 发布

阅读量528

点赞数

文章标签： linux声卡设备dsp设置音量

#include

struct fhead

{

unsigned char a[4];//四个字节存放'R','I','F','F'

long int b; //整个文件的长度-8;每个Chunk的size字段，都是表示除了本Chunk的ID和SIZE字段外的长度;

unsigned char c[4];//四个字节存放'W','A','V','E'

unsigned char d[4];//四个字节存放'f','m','t',''

long int e; //16后没有附加消息，18后有附加消息；一般为16，其他格式转来的话为18

short int f; //编码方式，一般为0x0001;

short int g; //声道数目，1单声道，2双声道;

long int h; //采样频率;

long int i; //每秒所需字节数;

short int j; //每个采样需要多少字节，若声道是双，则两个一起考虑;

short int k; //即量化位数

unsigned char p[4];//四个字节存放'd','a','t','a'

long int q; //语音数据部分长度，不包括文件头的任何部分

} wavehead;//定义WAVE文件的文件头结构体

#define LENGTH 8 //录音时间,秒

#define RATE 44100 //采样频率

#define SIZE 16 //量化位数

#define CHANNELS 2 //声道数目

#define RSIZE 8192 //buf的大小，

int main()

{

wavehead.a[0]='R';

wavehead.a[1]='I';

wavehead.a[2]='F';

wavehead.a[3]='F';

wavehead.b=LENGTH*RATE*CHANNELS*SIZE/8-8;

wavehead.c[0]='W';

wavehead.c[1]='A';

wavehead.c[2]='V';

wavehead.c[3]='E';

wavehead.d[0]='f';

wavehead.d[1]='m';

wavehead.d[2]='t';

wavehead.d[3]=' ';

wavehead.e=16;

wavehead.f=1;

wavehead.g=CHANNELS;

wavehead.h=RATE;

wavehead.i=RATE*CHANNELS*SIZE/8;

wavehead.j=CHANNELS*SIZE/8;

wavehead.k=SIZE;

wavehead.p[0]='d';

wavehead.p[1]='a';

wavehead.p[2]='t';

wavehead.p[3]='a';

wavehead.q=LENGTH*RATE*CHANNELS*SIZE/8;

int i;

unsigned char buf[RSIZE]; //每次循环取得RSIZE大小的容量，放入buf，然后写入文件；放音是相反。

//打开声卡设备，只读方式；并对声卡进行设置

int fd_dev_r= open("/dev/dsp", O_RDONLY,0777);

if (fd_dev_r < 0)

{

perror("Cannot open /dev/dsp device");

return 1;

}

int arg = SIZE;

if (ioctl(fd_dev_r, SOUND_PCM_WRITE_BITS, &arg) == -1) //设置量化位数

{

perror("Cannot set SOUND_PCM_WRITE_BITS ");

return 1;

}

arg = CHANNELS;

if (ioctl(fd_dev_r, SOUND_PCM_WRITE_CHANNELS, &arg) == -1) //设置声道数

{

perror("Cannot set SOUND_PCM_WRITE_CHANNELS");

return 1;

}

arg = RATE;

if (ioctl(fd_dev_r, SOUND_PCM_WRITE_RATE, &arg) == -1) //设置采样率

{

perror("Cannot set SOUND_PCM_WRITE_WRITE");

return 1;

}

//打开声卡设备，只写方式；并对声卡进行设置

int fd_dev_w = open("/dev/dsp", O_WRONLY,0777);

if (fd_dev_w < 0)

{

perror("Cannot open /dev/dsp device");

return 1;

}

arg = SIZE;

if (ioctl(fd_dev_w, SOUND_PCM_WRITE_BITS, &arg) == -1) //设置量化位数

{

perror("Cannot set SOUND_PCM_WRITE_BITS ");

return 1;

}

arg = CHANNELS;

if (ioctl(fd_dev_w, SOUND_PCM_WRITE_CHANNELS, &arg) == -1) //设置声道数

{

perror("Cannot set SOUND_PCM_WRITE_CHANNELS");

return 1;

}

arg = RATE;

if (ioctl(fd_dev_w, SOUND_PCM_WRITE_RATE, &arg) == -1) //设置采样率

{

perror("Cannot set SOUND_PCM_WRITE_WRITE");

return 1;

}

system("rm -f sound.wav");//清除已有的wav录音文件

int fd_f;

if(( fd_f = open("./sound.wav", O_CREAT|O_RDWR,0777))==-1)//创建一个wave格式语音文件

{

perror("cannot creat the sound file");

}

if(write(fd_f, &wavehead, sizeof(wavehead))==-1)//写入wave文件的文件头

{

perror("write to sound'head wrong!!");

}

for(i=0;i

{

if (read(fd_dev_r, buf, sizeof(buf)) != sizeof(buf))

{

perror("read wrong number of bytes");

}

if(write(fd_f, buf, sizeof(buf))==-1)

{

perror("write to sound wrong!!");

}

close(fd_dev_r);//关闭只xie方式的声卡

close(fd_f);//关闭wave文件

printf("play your sound now??\n y OR n\n");

if(getchar()=='y')

{

printf("Play...:\n");

if(( fd_f = open("./sound.wav", O_RDONLY,0777))==-1)

{

perror("cannot creat the sound file");

}

lseek(fd_f,44,SEEK_SET);

for(i=0;i

{

if (read(fd_f, buf, sizeof(buf)) != sizeof(buf)) //读语音文件

perror("write wrong number of bytes");

if (write(fd_dev_w, buf, sizeof(buf)) != sizeof(buf)) //送声卡播放

perror("wrote2 wrong number of bytes");

}

close(fd_f);

close(fd_dev_w);

return 0;

}

else

{

printf("bye!\n");

return 0;

}

return 0;

}