WhatsApp网页版怎么下载安卓
int fd=open(”/dev/video0″,O_RDWR);
2. 取得设备的capability,看看设备具有什么功能,比如是否具有视频输入,或者音频输入输出等。VIDIOC_QUERYCAP,struct v4l2_capability
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<a href="https://www.baidu.com/s?wd=v4l2&tn=44039180_cpr&fenlei=mv6quAkxTZn0IZRqIHckPjm4nH00T1whatsapp网页版被封收不到短信d9ujfLujc3uHbkrH0sPvRd0ZwV5Hcvrjm3rH6sPfKWUMw85HfYnjn4nH6sgvPsT6KdThsqpZwYTjCEQLGCpyw9Uz4Bmy-bIi4WUvYETgN-TLwGUv3EnHfknHbdnWbd" target="_blank" class="baidu-highlight">v4l2</a>_std_id std;
do {
ret= ioctl(fd, VIDIOC_QUERYSTD, &std);
} while (ret == -1 && errno == EAGwhatsapp网页版视频有美颜吗AIN);
switch (std) {
case V4L2_STD_NTSC:
//……
case V4L2_STD_PAL:
//……
}
3. 选择视频输入,一个视频设备可以有多个视频输入。VIDIOC_S_INPUT,struct v4l2_input(可不要)
4. 设置视频的制式和帧格式,制式包括PAL,NTSC,帧的格式个包web WhatsApp网页版登录括宽度和高度等。
VIDIOC_S_STD,VIDIOC_S_Fwhatsapp网页版安卓安装包MT,struct v4l2_std_id,struct v4l2_format
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struct v4l2_format fmt;
memset ( &fmt, 0, sizeof(fmt) );
fmt.tywhatsapp网页版好友头像变灰色pe = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = 320;
fmt.fmt.pix.height = 240;
fmt.fmt.pix.pixelformatwhatsapp网页版听不了语音 =whatsapp网页版群聊邀请好友 V4L2_PIX_FMT_JPEG;
if (ioctl(fd, VIDIOC_S_FMT, &fmt) < 0)
{
printf("set format failed\n");
//return 0;
}
5. 向驱动申请帧缓冲,一般不超过5个。struct v4l2_requestbuffers
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1whatsapp网页版安卓版本下载0
struct v4l2_requestbuffers req;
memset(&req, 0, sizeof (req));
req.count = 4;
req.type = V4L2_BUF_TYPE_VIDEO_CAPwhatsapp网页版最新版下载TURE;
req.memory = V4L2_MEMORY_MMAP;
if (ioctl(fd,VIDIOC_REQBUFS,&req) == -1)
{
perror("VIDIOC_REQBUFS error \n");
//return -1;
}
6.申请物理内存
将申三星怎么下载whwhatsapp网页版免费下载最新版atsapp网页版请到的帧缓冲映射到用户空间,这样就可以直接操作WhatsApp网页版下载安卓采集到的帧了,而不必去复制。将申请到的帧缓冲全部入队列,以便存放采集到的数据.VIDIOC_QBUF,struct v4l2_buffer
我linux版本3.12谢谢
但在别人电脑上又可以用 ~~
更奇怪的是我的电苹果whatsapp网页版怎样加好友脑除了这个摄像头~~其他的USB设备都能用
WhatsApp网页版请注明:WhatsApp网页版 » whatsapp网页版怎么下载安卓 怎么linux下检测 usb摄像头热插拔事件