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TQ2440的开发板,2.6.30.4内核,运行usb_camera程序后提示:huffman table don't exist! 查看代码:
if (ioctl(usb_fd, VIDIOC_DQBUF, &buf) < 0)
{
perror("VIDIOC_DQBUF failed.\n");
return -1;
}
unsigned char *ptcur = buffers[numBufs].start; //开始霍夫曼解码
int i1;
for (i1=0; i1<buf.bytesused; i1++)
{
if ((buffers[numBufs].start[i1] == 0x000000FF)
&& (buffers[numBufs].start[i1+1] == 0x000000C4))
{
break;
}
}
if (i1 == buf.bytesused)
printf("huffman table don't exist! \n");
int i;
ioctl(usb_fd, VIDIOC_DQBUF, &buf) 执行成功,buf.bytesused好像一直为0,这是不是表示摄像头没有采集到数据啊? |
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