#include?
#include?
#include?
#include?
#include??/*?getopt_long（）?*/
#include??/*?low-level?i/o?*/
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include??/*?for?videodev2.h?*/
#include?

#define?CLEAR（x）?memset?（&（x）?0?sizeof?（x））

typedef?enum?{
	IO_METHOD_READ
	IO_METHOD_MMAP
	IO_METHOD_USERPTR
}?io_method;

struct?buffer?{
	void?*?start;
	size_t?length;
};

static?char?*?dev_name?=?NULL;
static?io_method?io?=?IO_METHOD_MMAP;
static?int?fd?=?-1;
struct?buffer?*?buffers?=?NULL;
static?unsigned?int?n_buffers?=?0;
static?int?WIDTH?=?320;
static?int?HEIGHT?=?240;



static?void?errno_exit?（const?char?*?s）
{
	fprintf?（stderr?“%s?error?%d?%s\n“s?errno?strerror?（errno））;
	exit?（EXIT_FAILURE）;
}

static?int?xioctl?（int?fdint?requestvoid?*?arg）
{
	int?r;
	do?r?=?ioctl?（fd?request?arg）;
	while?（-1?==?r?&&?EINTR?==?errno）;
	return?r;
}

static?void?process_image?（const?void?*?p）
{
	fputc?（‘-‘?stdout）;
	fflush?（stdout）;
}

static?int?read_frame?（void）
{
	struct?v4l2_buffer?buf;
	unsigned?int?i;
	switch?（io）?{
	case?IO_METHOD_READ:
		if?（-1?==?read?（fd?buffers[0].start?buffers[0].length））?{
			switch?（errno）?{
			case?EAGAIN:
				return?0;
			case?EIO:
				/*?Could?ignore?EIO?see?spec.?*/
				/*?fall?through?*/
			default:
				errno_exit?（“read“）;
			}
		}
		process_image?（buffers[0].start）;
		break;
	case?IO_METHOD_MMAP:
		CLEAR?（buf）;
		buf.type?=?V4L2_BUF_TYPE_VIDEO_CAPTURE;
		buf.memory?=?V4L2_MEMORY_MMAP;
		if?（-1?==?xioctl?（fd?VIDIOC_DQBUF?&buf））?{
			switch?（errno）?{
			case?EAGAIN:
				return?0;
			case?EIO:
				/*?Could?ignore?EIO?see?spec.?*/
				/*?fall?through?*/
			default:
				errno_exit?（“VIDIOC_DQBUF“）;
			}
		}
		assert?（buf.index?		process_image?（buffers[buf.index].start）;
		if?（-1?==?xioctl?（fd?VIDIOC_QBUF?&buf））
			errno_exit?（“VIDIOC_QBUF“）;
		break;
	case?IO_METHOD_USERPTR:
		CLEAR?（buf）;
		buf.type?=?V4L2_BUF_TYPE_VIDEO_CAPTURE;
		buf.memory?=?V4L2_MEMORY_USERPTR;
		if?（-1?==?xioctl?（fd?VIDIOC_DQBUF?&buf））?{
			switch?（errno）?{
			case?EAGAIN:
				return?0;
			case?EIO:
				/*?Could?ignore?EIO?see?spec.?*/
				/*?fall?through?*/
			default:
				errno_exit?（“VIDIOC_DQBUF“）;
			}
		}
		for?（i?=?0;?i?			if?（buf.m.userptr?==?（unsigned?long）?buffers[i].start?&&?buf.length?==?buffers[i].length）
				break;
		assert?（i?		process_image?（（void?*）?buf.m.userptr）;
		if?（-1?==?xioctl?（fd?VIDIOC_QBUF?&buf））
			errno_exit?（“VIDIOC_QBUF“）;
		break;
	}
	return?1;
}
static?void?mainloop?（void）
{
	unsigned?int?count;
	count?=?1000;
	while?（count--?>?0）?{
		for?（;;）?{
			fd_set?fds;
			struct?timeval?tv;
			int?r;
			FD_ZERO?（&fds）;
			

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2014-01-03?11:39??my_v4l2\
?????文件?????????205??2014-01-03?11:38??my_v4l2\buildarm.sh
?????文件?????????203??2014-01-03?11:38??my_v4l2\buildhost.sh
?????文件???????12261??2014-01-03?11:38??my_v4l2\camera.c
?????文件?????????114??2014-01-03?11:38??my_v4l2\main.cpp
?????文件????????4775??2014-01-03?11:38??my_v4l2\main_form.cpp
?????文件?????????419??2014-01-03?11:38??my_v4l2\main_form.h
?????文件?????????691??2014-01-03?11:38??my_v4l2\main_form_base.ui
?????文件?????????218??2014-01-03?11:38??my_v4l2\myv4l2.desktop
?????文件????????2061??2014-01-03?11:38??my_v4l2\myv4l2.png
?????文件?????????170??2014-01-03?11:38??my_v4l2\myv4l2.pro
?????文件????????6345??2014-01-03?11:38??my_v4l2\v4l2.cpp
?????文件?????????846??2014-01-03?11:38??my_v4l2\v4l2.h