音频实时播放有问题，求解答！
开发板：OK6410；内核：linux2.6.28；音频采集后，播放滞后一到两秒，在一个板子上测试的，如果传输后那就更滞后，所以求版主和各位高手求解，下面是代码
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#include <stdio.h>
#include <linux/soundcard.h>
#define LENGTH 60 /* 存储秒数 60ms*/
#define RATE 8000 /* 采样频率 */
#define SIZE 16 /* 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;
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");
}
}
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