获取USB摄像头的1080p的JPEG格式的图片20180608_1806.7z 电脑上的系统：ubuntu14.04
// http://www.linuxidc.com/Linux/2011-03/33020.htm
// V4L2摄像头获取单幅图片测试程序（MMAP模式）
// [日期：2011-03-06] 来源：Linux社区 作者：aokikyon [字体：大 中 小]
//
// #加了点注释
//
// #Rockie Cheng
// printf
#include <stdio.h>
#include <stdlib.h>
// memset
#include <string.h>
#include <assert.h>
#include <getopt.h>
#include <fcntl.h>
// close write usleep read
#include <unistd.h>
#include <errno.h>
#include <malloc.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/time.h>
// mmap
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <asm/types.h>
#include <linux/videodev2.h>
// pthread_create pthread_join
#include <pthread.h>
#define CLEAR(x) memset (&(x), 0, sizeof (x))
#define REQ_COUNT 6
#define uchar unsigned char
struct buffer {
void * start;
size_t length;
};
static char * dev_name = "/dev/video0";//摄像头设备名
static int fd = -1;
struct buffer * buffers = NULL;
// static unsigned int n_buffers = 0;
// 2012-7-13 11:33 camera flag
// static int iFlagCamera = 0;
volatile int iFlagCamera = 0;
// 函数名称：thread1
// 函数功能：用于接受键盘的输入，之后通知thread2抓图
// 参数列表：
// 返回值 ：
void thread1(void)
{
char ch;
printf("\n !!!!Warning!!!!\n Max 1000 color bmp\n Input the char: \n");
printf("\n !!!!press o an capture 1 frame picture! \n");
printf("\n !!!!press t an capture 10 frame picture! \n");
printf("\n !!!!press h an capture 100 frame picture! \n");
while(1)
{
while((ch=getchar()) != '\n')
{
printf("%c\n", ch);
if('o'==ch)
{
iFlagCamera = 1;
printf("thread1=%d\n", iFlagCamera);
}
else if('t'==ch)
{
iFlagCamera = 10;
printf("thread1=%d\n", iFlagCamera);
}
else if('h'==ch)
{
iFlagCamera = 101;
printf("thread1=%d\n", iFlagCamera);
}
else if('q'==ch)
{
iFlagCamera = 10001;
printf("thread1=%d\n", iFlagCamera);
}
}
if(iFlagCamera>1000)
{
break;
}
}
printf("\n exit\n");
}
FILE *file_fd;
int i;
int r;
struct v4l2_capability cap;
struct v4l2_format fmt;
struct v4l2_buffer buf[REQ_COUNT];
struct v4l2_requestbuffers req;
struct v4l2_buffer tmp_buf;
enum v4l2_buf_type type;
struct timeval tv;
struct timeval tp1;
struct timeval tp3;
struct timeval tp4;
// void * mem[REQ_COUNT];
fd_set fds;
// // http://blog.sina.com.cn/s/blog_602f87700100znq7.html
// // 嵌入式Linux下Camera编程--V4L2
// // Z:\kernel_imx\include\linux\videodev2.h
// /* Values for 'capabilities' field */
#define V4L2_CAP_VIDEO_CAPTURE 0x00000001 /* Is a video capture device */
#define V4L2_CAP_VIDEO_OUTPUT 0x00000002 /* Is a video output device */
#define V4L2_CAP_VIDEO_OVERLAY 0x00000004 /* Can do video overlay */
#define V4L2_CAP_VBI_CAPTURE 0x00000010 /* Is a raw VBI capture device */
#define V4L2_CAP_VBI_OUTPUT 0x00000020 /* Is a raw VBI output device */
#define V4L2_CAP_SLICED_VBI_CAPTURE 0x00000040 /* Is a sliced VBI capture device */
#define V4L2_CAP_SLICED_VBI_OUTPUT 0x00000080 /* Is a sliced VBI output device */
#define V4L2_CAP_RDS_CAPTURE 0x00000100 /* RDS data capture */
#define V4L2_CAP_VIDEO_OUTPUT_OVERLAY 0x00000200 /* Can do video output overlay */
#define V4L2_CAP_HW_FREQ_SEEK 0x00000400 /* Can do hardware frequency seek */
#define V4L2_CAP_RDS_OUTPUT 0x00000800 /* Is an RDS encoder */
/* Is a video capture device that supports multiplanar formats */
#define V4L2_CAP_VIDEO_CAPTURE_MPLANE 0x00001000
/* Is a video output device that supports multiplanar formats */
#define V4L2_CAP_VIDEO_OUTPUT_MPLANE 0x00002000
#define V4L2_CAP_TUNER 0x00010000 /* has a tuner */
#define V4L2_CAP_AUDIO 0x00020000 /* has audio support */
#define V4L2_CAP_RADIO 0x00040000 /* is a radio device */
#define V4L2_CAP_MODULATOR 0x00080000 /* has a modulator */
#define V4L2_CAP_READWRITE 0x01000000 /* read/write systemcalls */
#define V4L2_CAP_ASYNCIO 0x02000000 /* async I/O */
#define V4L2_CAP_STREAMING 0x04000000 /* streaming I/O ioctls */
void getCameraCapabilities(int iCameraCapabilities)
{
if(iCameraCapabilities&V4L2;_CAP_VIDEO_CAPTURE)
{
printf("!!!!**** camera ****!!!! Is a video capture device\n");
}
if(iCameraCapabilities&V4L2;_CAP_VIDEO_OUTPUT)
{
printf("**** camera **** Is a video output device\n");
}
if(iCameraCapabilities&V4L2;_CAP_VIDEO_OVERLAY)
{
printf("**** camera **** Can do video overlay\n");
}
if(iCameraCapabilities&V4L2;_CAP_VBI_CAPTURE)
{
printf("**** camera **** Is a raw VBI capture device\n");
}
if(iCameraCapabilities&V4L2;_CAP_VBI_OUTPUT)
{
printf("**** camera **** Is a raw VBI output device\n");
}
if(iCameraCapabilities&V4L2;_CAP_SLICED_VBI_CAPTURE)
{
printf("**** camera **** Is a sliced VBI capture device\n");
}
if(iCameraCapabilities&V4L2;_CAP_SLICED_VBI_OUTPUT)
{
printf("**** camera **** Is a sliced VBI output device\n");
}
if(iCameraCapabilities&V4L2;_CAP_RDS_CAPTURE)
{
printf("**** camera **** RDS data capture\n");
}
if(iCameraCapabilities&V4L2;_CAP_VIDEO_OUTPUT_OVERLAY)
{
printf("**** camera **** Can do video output overlay\n");
}
if(iCameraCapabilities&V4L2;_CAP_HW_FREQ_SEEK)
{
printf("**** camera **** Can do hardware frequency seek\n");
}
if(iCameraCapabilities&V4L2;_CAP_RDS_OUTPUT)
{
printf("**** camera **** Is an RDS encoder\n");
}
if(iCameraCapabilities&V4L2;_CAP_VIDEO_CAPTURE_MPLANE)
{
printf("**** camera **** Is a video capture device that supports multiplanar formats\n");
}
if(iCameraCapabilities&V4L2;_CAP_VIDEO_OUTPUT_MPLANE)
{
printf("**** camera **** Is a video output device that supports multiplanar formats\n");
}
if(iCameraCapabilities&V4L2;_CAP_TUNER)
{
printf("**** camera **** has a tuner\n");
}
if(iCameraCapabilities&V4L2;_CAP_AUDIO)
{
printf("**** camera **** has audio support\n");
}
if(iCameraCapabilities&V4L2;_CAP_RADIO)
{
printf("**** camera **** is a radio device\n");
}
if(iCameraCapabilities&V4L2;_CAP_MODULATOR)
{
printf("**** camera **** has a modulator\n");
}
if(iCameraCapabilities&V4L2;_CAP_READWRITE)
{
printf("**** camera **** read/write systemcalls\n");
}
if(iCameraCapabilities&V4L2;_CAP_ASYNCIO)
{
printf("**** camera **** async I/O\n");
}
if(iCameraCapabilities&V4L2;_CAP_STREAMING)
{
printf("!!!!**** camera ****!!!! streaming I/O ioctls\n");
}
}
// 公司 ：红蝶科技（深圳）有限公司
// 作者 ：蒋海滨 0755-86139000-1052
// 文件名 ：main.c
// 功能 ：N001
// 日期 ：2012-7-28 10:08
// 维护者 ：
// 维护记录：
// #include "imgprocess.h"
#include <sys/time.h>
// int main ()
void thread2(void)
{
int iCounterCamera = 0;
int iCounter100frame = 0;
// 2012-11-8 05:27下午 RGB24 640*480分辨率的BMP图像头文件
// unsigned char head[54] = {0x42,0x4d,0x36,0x10,0x0e,0x00,0x00,0x00,0x00,0x00,0x36,0x00,0x00,0x00,0x28,0x00,0x00,0x00,0x80,0x02,0x00,0x00,0xe0,0x01,0x00,0x00,0x01,0x00,0x18,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
// 抓取Y分量所取得的灰度图
//unsigned char graybmphead[1078] = { 0x42, 0x4d, 0x36, 0xb4, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x36, 0x04, 0x00, 0x00, 0x28, 0x00, 0x00, 0x00, 0x80, 0x02, 0x00, 0x00, 0xe0, 0x01, 0x00, 0x00, 0x01, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x00, 0x02, 0x02, 0x02, 0x00, 0x03, 0x03, 0x03, 0x00, 0x04, 0x04, 0x04, 0x00, 0x05, 0x05, 0x05, 0x00, 0x06, 0x06, 0x06, 0x00, 0x07, 0x07, 0x07, 0x00, 0x08, 0x08, 0x08, 0x00, 0x09, 0x09, 0x09, 0x00, 0x0a, 0x0a, 0x0a, 0x00, 0x0b, 0x0b, 0x0b, 0x00, 0x0c, 0x0c, 0x0c, 0x00, 0x0d, 0x0d, 0x0d, 0x00, 0x0e, 0x0e, 0x0e, 0x00, 0x0f, 0x0f, 0x0f, 0x00, 0x10, 0x10, 0x10, 0x00, 0x11, 0x11, 0x11, 0x00, 0x12, 0x12, 0x12, 0x00, 0x13, 0x13, 0x13, 0x00, 0x14, 0x14, 0x14, 0x00, 0x15, 0x15, 0x15, 0x00, 0x16, 0x16, 0x16, 0x00, 0x17, 0x17, 0x17, 0x00, 0x18, 0x18, 0x18, 0x00, 0x19, 0x19, 0x19, 0x00, 0x1a, 0x1a, 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0x44, 0x44, 0x44, 0x00, 0x45, 0x45, 0x45, 0x00, 0x46, 0x46, 0x46, 0x00, 0x47, 0x47, 0x47, 0x00, 0x48, 0x48, 0x48, 0x00, 0x49, 0x49, 0x49, 0x00, 0x4a, 0x4a, 0x4a, 0x00, 0x4b, 0x4b, 0x4b, 0x00, 0x4c, 0x4c, 0x4c, 0x00, 0x4d, 0x4d, 0x4d, 0x00, 0x4e, 0x4e, 0x4e, 0x00, 0x4f, 0x4f, 0x4f, 0x00, 0x50, 0x50, 0x50, 0x00, 0x51, 0x51, 0x51, 0x00, 0x52, 0x52, 0x52, 0x00, 0x53, 0x53, 0x53, 0x00, 0x54, 0x54, 0x54, 0x00, 0x55, 0x55, 0x55, 0x00, 0x56, 0x56, 0x56, 0x00, 0x57, 0x57, 0x57, 0x00, 0x58, 0x58, 0x58, 0x00, 0x59, 0x59, 0x59, 0x00, 0x5a, 0x5a, 0x5a, 0x00, 0x5b, 0x5b, 0x5b, 0x00, 0x5c, 0x5c, 0x5c, 0x00, 0x5d, 0x5d, 0x5d, 0x00, 0x5e, 0x5e, 0x5e, 0x00, 0x5f, 0x5f, 0x5f, 0x00, 0x60, 0x60, 0x60, 0x00, 0x61, 0x61, 0x61, 0x00, 0x62, 0x62, 0x62, 0x00, 0x63, 0x63, 0x63, 0x00, 0x64, 0x64, 0x64, 0x00, 0x65, 0x65, 0x65, 0x00, 0x66, 0x66, 0x66, 0x00, 0x67, 0x67, 0x67, 0x00, 0x68, 0x68, 0x68, 0x00, 0x69, 0x69, 0x69, 0x00, 0x6a, 0x6a, 0x6a, 0x00, 0x6b, 0x6b, 0x6b, 0x00, 0x6c, 0x6c, 0x6c, 0x00, 0x6d, 0x6d, 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0xea, 0xea, 0xea, 0x00, 0xeb, 0xeb, 0xeb, 0x00, 0xec, 0xec, 0xec, 0x00, 0xed, 0xed, 0xed, 0x00, 0xee, 0xee, 0xee, 0x00, 0xef, 0xef, 0xef, 0x00, 0xf0, 0xf0, 0xf0, 0x00, 0xf1, 0xf1, 0xf1, 0x00, 0xf2, 0xf2, 0xf2, 0x00, 0xf3, 0xf3, 0xf3, 0x00, 0xf4, 0xf4, 0xf4, 0x00, 0xf5, 0xf5, 0xf5, 0x00, 0xf6, 0xf6, 0xf6, 0x00, 0xf7, 0xf7, 0xf7, 0x00, 0xf8, 0xf8, 0xf8, 0x00, 0xf9, 0xf9, 0xf9, 0x00, 0xfa, 0xfa, 0xfa, 0x00, 0xfb, 0xfb, 0xfb, 0x00, 0xfc, 0xfc, 0xfc, 0x00, 0xfd, 0xfd, 0xfd, 0x00, 0xfe, 0xfe, 0xfe, 0x00, 0xff, 0xff, 0xff, 0x00 };
//int g_nWidth = 640;
//int g_nHeight = 480;
int g_nWidth = 1920;
int g_nHeight = 1080;
// 2012-8-8 04:29下午 V4L2初始化摄像头
// 注释资料来源：
// http://wenku.baidu.com/view/2f92ce8c680203d8ce2f247f.html
// 基于Linux视频驱动接口V4L2视频采集编程
// 用非阻塞模式打开摄像头设备
if((fd=open(dev_name,O_RDWR | O_NONBLOCK,0))<0)
{
printf("Error: open %s\n",dev_name);
// return 0;
return;
}
else
{
printf("**** wyb01 Open camera success!!!! fd=%d\n", fd);
}
// 获取当前视频设备支持的视频格式
struct v4l2_fmtdesc fmtd;
int ret = 0;
memset(&fmtd;, 0, sizeof(fmtd));
fmtd.index = 0;
fmtd.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
while ((ret = ioctl(fd, VIDIOC_ENUM_FMT, &fmtd;)) == 0)
{
fmtd.index++;
printf(" pixelformat = ''%c%c%c%c'', description = ''%s'' \n", fmtd.pixelformat & 0xFF, (fmtd.pixelformat >> 8) & 0xFF, (fmtd.pixelformat >> 16) & 0xFF, (fmtd.pixelformat >> 24) & 0xFF, fmtd.description);
}
// 查询视频设备的功能；执行完 VIDIOC_QUERYCAP 命令后，cap变量中包含了该视频设备的能力信息，
// 程序中通过检查cap中的设备能力信息来判断设备是否支持某项功能。
if(ioctl(fd, VIDIOC_QUERYCAP, ∩)<0)
{
printf("Error: query cap\n");
// return 0;
return;
}
printf("\n capabilities= 0xx\n",cap.capabilities);
int iCapCapabilities=cap.capabilities;
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = g_nWidth;
fmt.fmt.pix.height = g_nHeight;
// 2018/6/8 17:19 只对USB摄像头有效！
fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_MJPEG;
//fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
// fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUV422P;
fmt.fmt.pix.field = V4L2_FIELD_BOTTOM;
printf("**** fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUV422P; ****\n");
// 设置视频设备的视频数据格式，例如设置视频图像数据的长、宽，图像格式（JPEG、YUYV 格式）；
// 注意：如果该视频设备驱动不支持你所设定的图像格式，
// 视频驱动会重新修改struct v4l2_format 结构体变量的值为该视频设备所支持的图像格式，
// 所以在程序设计中，设定完所有的视频格式后，要获取实际的视频格式，
// 要重新读取struct v4l2_format 结构体变量。
if(ioctl(fd,VIDIOC_S_FMT, &fmt;)<0)
{
printf("Error:VIDIOC_S_FMT \n");
// return 0;
return;
}
// 读取当前驱动的频捕获格式
// 2012-8-8 03:07下午 确认所设置的制式是否是我们所需要的制式
struct v4l2_format fmt2;
fmt2.type=V4L2_BUF_TYPE_VIDEO_CAPTURE;
ret = ioctl(fd,VIDIOC_G_FMT, &fmt2;);
printf("VIDIOC_G_FMT ret=%d \n", ret);
printf("pixelformat = ''%c%c%c%c''\n", fmt2.fmt.pix.pixelformat & 0xFF, (fmt2.fmt.pix.pixelformat >> 8) & 0xFF, (fmt2.fmt.pix.pixelformat >> 16) & 0xFF, (fmt2.fmt.pix.pixelformat >> 24) & 0xFF);
req.count = REQ_COUNT ;
req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
req.memory = V4L2_MEMORY_MMAP;
// 请求V4L2驱动分配视频缓冲区 （申请 V4L2视频驱动分配内存），V4L2是视频设备的驱动层，
// 位于内核空间，所以通过 VIDIOC_REQBUFS 控制命令字申请的内存位于内核空间，
// 应用程序不能直接访问，需要通过调用 mmap内存映射函数把内核空间内存映射到用户空间后，
// 应用程序通过访问用户空间地址来访问内核空间。
// 注意： VIDIOC_REQBUFS会修改tV4L2_reqbuf的count值，
// tV4L2_reqbuf的count值返回实际申请成功的视频缓冲区数目。
if(ioctl(fd, VIDIOC_REQBUFS, &req;)<0)
{
printf("Error:VIDIOC_REQBUFS\n");
// return 0;
return;
}
printf("req.count=%d\n",req.count);
buffers = calloc (req.count, sizeof (*buffers));//内存中建立对应空间
printf(" sizeof (*buffers) =x\n", sizeof (*buffers));
for(i=0;i<req.count;i++)
{
buf[i].type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf[i].memory = V4L2_MEMORY_MMAP;
buf[i].index = i;
// 查询已经分配的 V4L2的视频缓冲区的相关信息，包括视频缓冲区的使用状态、在内核空间的
// 偏移地址、缓冲区长度等。在应用程序设计中通过调VIDIOC_QUERYBUF 来获取内核空间的
// 视频缓冲区信息，然后调用函数mmap把内核空间地址映射到用户空间，这样应用程序才能够
// 访问位于内核空间的视频缓冲区。通过调用 VIDIOC_QUERYBUF 取得内核空间的缓冲区信息后，
// 接着调用 mmap函数把内核空间缓冲区映射到用户空间。
if(ioctl(fd, VIDIOC_QUERYBUF, buf+i)<0)
{
printf("Error:VIDIOC_QUERYBUF\n");
// return 0;
return;
}
buffers[i].length = buf[i].length;
buffers[i].start =
mmap (NULL /* start anywhere */, //通过mmap建立映射关系
buf[i].length,
PROT_READ | PROT_WRITE /* required */,
MAP_SHARED /* recommended */,
fd, buf[i].m.offset);
// printf("**** i=%d buf.length=%d, buffers[i].start=x buf.m.offset=x\n", i, buf[i].length, *( (unsigned int *) (buffers[i].start) ), buf.m.offset);
printf("**** i=%d buf.length=%d, buffers[i].start=x buf.m.offset=x\n", i, buf[i].length, *( (unsigned int *) (buffers[i].start) ), buf[i].m.offset);
buf[i].type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf[i].memory = V4L2_MEMORY_MMAP;
buf[i].index = i;
// 投放一个空的视频缓冲区到视频缓冲区输入队列中。函数执行成功后，指令的视频缓冲区
// 进入视频输入队列，在启动视频设备拍摄图像时，相应的视频数据被保存到视频输入队列
// 相应的视频缓冲区中。
if(ioctl(fd, VIDIOC_QBUF, buf+i)<0)
{
printf("Error: VIDIOC_QBUF\n");
}
}
// 启动视频采集命令，应用程序调用 VIDIOC_STREAMON 启动视频采集命令后，
// 视频设备驱动程序开始采集视频数据，并把采集到的视频数据保存到
// 视频驱动的视频缓冲区中。
type=V4L2_BUF_TYPE_VIDEO_CAPTURE;
if(ioctl(fd, VIDIOC_STREAMON, &type;)<0)
{
printf("Error: VIDIOC_STREAMON\n");
// return 0;
return;
}
gettimeofday(&tv;, NULL);
int iSecond = tv.tv_sec;
int iuSecond = tv.tv_usec;
int iCostTime = 0;
int iSecond3 = tv.tv_sec;
int iuSecond3 = tv.tv_usec;
int iCostTime3 = 0;
int iSecond4 = tv.tv_sec;
int iuSecond4 = tv.tv_usec;
int iCostTime4 = 0;
int iCameraCounter = 0;
int iFrameCounter = 0;
int iFrameCounter3 = 0;
int iFrameCounter4 = 0;
while(1)
{
// 2013/5/14 17:59:02 按q退出
if(iFlagCamera>1000)
{
break;
}
// 2013-5-14 19:13 测帧率
iFrameCounter++;
if(iFrameCounter0==0)
{
gettimeofday(&tp1;, NULL);
iCostTime = (tp1.tv_sec - iSecond)*1000000 + tp1.tv_usec - iuSecond;
// printf("@@@@ 100 frame=%u us, fps=%f\n",iCostTime, 1000000*100.0/iCostTime) ;
iSecond = tp1.tv_sec;
iuSecond = tp1.tv_usec;
}
FD_ZERO (&fds;);
FD_SET (fd, &fds;);
tv.tv_sec = 2;
tv.tv_usec = 0;
// VIDIOC_STREAMON函数执行成功后，视频设备驱动程序开始采集视频数据，此时应用程序
// 一般通过调用 select 函数来判断一帧视频数据是否采集完成，当视频设备驱动完成
// 一帧视频数据采集并保存到视频缓冲区中时，select 函数返回，应用程序接着可以
// 读取视频数据；否则 select 函数阻塞直到视频数据采集完成。
r = select (fd + 1, &fds;, NULL, NULL, &tv;);
// printf("------------r=%d\n",r);
if(r<0)
{
// continue;
// return 0;
return;
}
tmp_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
tmp_buf.memory = V4L2_MEMORY_MMAP;
tmp_buf.index = 0;
// 从视频缓冲区的输出队列中取得一个已经保存有一帧视频数据的视频缓冲区。
// 函数VIDIOC_DQBUF执行成功后，相应的内核视频缓冲区中保存有当前拍摄到的
// 视频数据，应用程序可以通过访问用户空间来读取该视频数据。
if(ioctl(fd, VIDIOC_DQBUF, &tmp;_buf)<0)
{
// printf("**** Error:VIDIOC_DQBUF\n");
// return 0;
continue;
}
iFrameCounter3++;
if(iFrameCounter30==0)
{
gettimeofday(&tp3;, NULL);
iCostTime3 = (tp3.tv_sec - iSecond3)*1000000 + tp3.tv_usec - iuSecond3;
// printf("####100 frame=%u us, fps=%f\n", iCostTime3, 1000000*100.0/iCostTime3) ;
iSecond3 = tp3.tv_sec;
iuSecond3 = tp3.tv_usec;
}
// 2013/2/20 19:54:10 存储灰度图
// if(j>200)
// if(j>20)
if(iFlagCamera)
{
iCameraCounter++;
iFlagCamera--;
// 写灰度图
char GRAYname[100];
// sprintf(GRAYname, "grayd.bmp", j);
// sprintf(GRAYname, "/sdcard/grayd.bmp", j);
//sprintf(GRAYname, "/sdcard/grayd.bmp", iCameraCounter);
//sprintf(GRAYname, "/sdcard/yuyvd.yuv", iCameraCounter);
//Segmentation fault (core dumped)
//sprintf(GRAYname, "/tmp/yuyvd.yuv", iCameraCounter);
sprintf(GRAYname, "jpegd.jpg", iCameraCounter);
file_fd = fopen(GRAYname, "w");
if(file_fd)
{
// fwrite(graybmphead, sizeof (unsigned char),1078,fp_YUV );
//fwrite(graybmphead, sizeof (unsigned char), 1078, file_fd );
// 获取YUYV的图片
// fwrite(buffers[tmp_buf.index].start, 640*480*2, 1, file_fd);
// fwrite(ucGrayBMP, 640*480, 1, file_fd);
// 获取JPEG的图片
//fwrite(buffers[buf.index].start, buffers[buf.index].length, 1, file_fd);
fwrite(buffers[tmp_buf.index].start, buffers[tmp_buf.index].length, 1, file_fd);
}
fclose (file_fd);
// printf ("**** wyb3 write BMP success j=%d!!!!\n", j);
printf ("**** wyb3 write BMP success j=%d!!!!\n", iCameraCounter);
}
tmp_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
tmp_buf.memory = V4L2_MEMORY_MMAP;
// 投放一个空的视频缓冲区到视频缓冲区输入队列中。函数执行成功后，指令的视频缓冲区
// 进入视频输入队列，在启动视频设备拍摄图像时，相应的视频数据被保存到视频输入队列
// 相应的视频缓冲区中。
if(ioctl(fd, VIDIOC_QBUF, &tmp;_buf)<0)
{
// printf("#### Error:VIDIOC_QBUF\n");
// return 0;
continue;
}
iFrameCounter4++;
if(iFrameCounter40==0)
{
gettimeofday(&tp4;, NULL);
iCostTime4 = (tp4.tv_sec - iSecond4)*1000000 + tp4.tv_usec - iuSecond4;
// printf("@@@@ 100 frame=%u us, fps=%f\n",iCostTime, 1000000*100.0/iCostTime) ;
// printf("####100 frame=%u us, fps=%f\n", iCostTime3, 1000000*100.0/iCostTime3) ;
// printf("^^^^ 100 frame=%u us, fps=%f\n", iCostTime4, 1000000*100.0/iCostTime4) ;
// fps = 1/( (iCostTime4/1000000)/100 )
printf("^^^^ 100 frame=%u us, fps=%f iCounter100frame=%d\n", iCostTime4, 1000000*100.0/iCostTime4, iCounter100frame) ;
iSecond4 = tp4.tv_sec;
iuSecond4 = tp4.tv_usec;
iCounter100frame++;
printf("\n\n") ;
}
}
// 停止视频采集命令，应用程序调用 VIDIOC_ STREAMOFF停集命令后，
// 视频设备驱动程序不再采集视频数据。
if(ioctl(fd, VIDIOC_STREAMOFF, &type;)<0)
{
printf("Error:VIDIOC_STREAMOFF\n");
// return 0;
return;
}
printf("================streamoff\n");
printf("\n capabilities= 0xx, iCapCapabilities=0xx \n",cap.capabilities, iCapCapabilities);
getCameraCapabilities(iCapCapabilities);
// 解除内存映射
for(i=0;i<req.count;i++)
{
munmap(buffers[i].start, buf[i].length);
}
close(fd);
// return 0;
return;
}
// 函数名称：main
// 函数功能：主函数
// 参数列表：
// 返回值 ：
int main(int argc, char **argv)
{
pthread_t id1;
pthread_t id2;
int ret2;
ret2=pthread_create(&id1;,NULL,(void *) thread1,NULL);
if(ret2!=0)
{
printf ("Create pthread1 error!\n");
// exit (1);
return 0;
}
ret2=pthread_create(&id2;,NULL,(void *) thread2,NULL);
if(ret2!=0)
{
printf ("Create pthread2 error!\n");
// exit (1);
return 0;
}
pthread_join(id1,NULL);
pthread_join(id2,NULL);
return 0;
}
获取USB摄像头的1080p的JPEG格式的图片20180608_1806.7z （37个子文件） 
获取USB摄像头的1080p的JPEG格式的图片 
p1080_mjpeg.c 8KB
test.7z 179KB
test1.jpg 600KB
