想在linux 下进行语音编码!但是linux录音的函数是read(fd,buf,size)
其中buf是存储录音数据的,但是它的类型是char*的,我想把它变成short*类型的,
然后存储为short类型的数组中,请问应该怎么编程?????
录音程序如下:
#include <sys/ioctl.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/soundcard.h>
#define LENGTH 3
/* 存储秒数 */
#define RATE 8000
/* 采样频率 */
#define SIZE 8
/* 量化位数 */
#define CHANNELS 1
/* 声道数目 */
/* 用于保存数字音频数据的内存缓冲区 */
unsigned char buf[LENGTH*RATE*SIZE*CHANNELS/8];
int main()
{
int fd;
/* 声音设备的文件描述符 */
int arg;
/* 用于ioctl调用的参数 */
int status;
/* 系统调用的返回值 */
/* 打开声音设备 */
fd = open("/dev/dsp", O_RDWR);
if (fd < 0)
{
perror("open of /dev/dsp failed");
exit(1);
}
/* 设置采样时的量化位数 */
arg = SIZE;
status = ioctl(fd, SOUND_PCM_WRITE_BITS, &arg);
if (status == -1)
perror("SOUND_PCM_WRITE_BITS ioctl failed");
if (arg != SIZE)
perror("unable to set sample size");
/* 设置采样时的声道数目 */
arg = CHANNELS;
status = ioctl(fd, SOUND_PCM_WRITE_CHANNELS, &arg);
if (status == -1)
perror("SOUND_PCM_WRITE_CHANNELS ioctl failed");
if (arg != CHANNELS)
perror("unable to set number of channels");
/* 设置采样时的采样频率 */
arg = RATE;
status = ioctl(fd, SOUND_PCM_WRITE_RATE, &arg);
if (status == -1)
perror("SOUND_PCM_WRITE_WRITE ioctl failed");
/* 循环,直到按下Control-C */
while (1)
{
printf("Say something:\n");
status = read(fd, buf, sizeof(buf)); /* 录音 */
if (status != sizeof(buf))
perror("read wrong number of bytes");
printf("You said:\n");
status = write(fd, buf, sizeof(buf)); /* 回放 */
if (status != sizeof(buf))
perror("wrote wrong number of bytes");
/* 在继续录音前等待回放结束 */
status = ioctl(fd, SOUND_PCM_SYNC, 0);
if (status == -1)
perror("SOUND_PCM_SYNC ioctl failed");
}
}