OK6410A 开发板 (八) 7 linux-5.11 OK6410A usb camera移植

代码 : https://github.com/lisider/linux/tree/ok6410a-linux-5.11

提交id : 0cf53aa024fbd417f0796a77ff7f9b891680dac8

defconfig : arch/arm/configs/ok6410A_sdboot_mini_net_lcd_x11_usb_debug_uvc_defconfig

用户空间代码 uvc_cam_test

Makefile

CROSS_COMPILE =arm-none-linux-gnueabi-

KERNELDIR =

CFLAGS = -I$(KERNELDIR)/include -O -Wall -static

CC = $(CROSS_COMPILE)gcc

AR = $(CROSS_COMPILE)ar

ALL : uvc_cam_test

test_usb_camera:  uvc_cam_test.c

        $(CC) -o  uvc_cam_test  uvc_cam_test.c $(CFLAGS)

clean :

        rm -rf  uvc_cam_test

uvc_cam_test.c

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

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

struct buffer {

void * start;

size_t length;

};

static char *  dev_name = NULL;

static int fd = -1;

struct buffer * buffers = NULL;

static unsigned int n_buffers = 0;

static int time_in_sec_capture=5;

static int fbfd = -1;

static struct fb_var_screeninfo vinfo;

static struct fb_fix_screeninfo finfo;

static char *fbp=NULL;

static long screensize=0;

static void errno_exit (const char * s)

{

fprintf (stderr, "%s error %d, %sn",s, errno, strerror (errno));

exit (EXIT_FAILURE);

}

static int xioctl (int fd,int request,void * arg)

{

int r;

do r = ioctl (fd, request, arg);

while (-1 == r && EINTR == errno);

return r;

}

inline int clip(int value, int min, int max) {

return (value > max ? max : value < min ? min : value);

}

static void process_image (const void * p){

//ConvertYUVToRGB32

unsigned char* in=(unsigned char*)p;

int width=320;

int height=240;

int istride=width*2;

int x,y,j;

int y0,u,y1,v,r,g,b;

long location=0;

for ( y = 10; y < height + 10; ++y) {

for (j = 0, x=10; j < width * 2 ; j += 4,x +=2) {

location = (x+vinfo.xoffset) * (vinfo.bits_per_pixel/8) +

(y+vinfo.yoffset) * finfo.line_length;

y0 = in[j];

u = in[j + 1] - 128;

y1 = in[j + 2];

v = in[j + 3] - 128;

r = (298 * y0 + 409 * v + 128) >> 8;

g = (298 * y0 - 100 * u - 208 * v + 128) >> 8;

b = (298 * y0 + 516 * u + 128) >> 8;

fbp[ location + 0] = ((clip(g, 0, 255)&0x1c)<< 3 ) | ( clip(b, 0, 255)  >> 3 );

fbp[ location + 1] = ((clip(r, 0, 255) & 0xf8) ) | ( clip(g, 0, 255)>> 5);

r = (298 * y1 + 409 * v + 128) >> 8;

g = (298 * y1 - 100 * u - 208 * v + 128) >> 8;

b = (298 * y1 + 516 * u + 128) >> 8;

fbp[ location + 2] = ((clip(g, 0, 255)&0x1c)<< 3 ) | ( clip(b, 0, 255)  >> 3 );

fbp[ location + 3] = ((clip(r, 0, 255) & 0xf8) ) | ( clip(g, 0, 255)>> 5);

}

in +=istride;

}

}

static int read_frame (void)

{

struct v4l2_buffer buf;

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:

default:

errno_exit ("VIDIOC_DQBUF");

}

}

assert (buf.index < n_buffers);

//  printf("v4l2_pix_format->field(%d)n", buf.field);

//assert (buf.field ==V4L2_FIELD_NONE);

process_image (buffers[buf.index].start);

if (-1 == xioctl (fd, VIDIOC_QBUF, &buf))

errno_exit ("VIDIOC_QBUF");

return 1;

}

static void run (void)

{

int frames;

frames = 30 * time_in_sec_capture;

while (frames-- > 0) {

for (;;) {

fd_set fds;

struct timeval tv;

int r;

FD_ZERO (&fds);

FD_SET (fd, &fds);

tv.tv_sec = 2;

tv.tv_usec = 0;

r = select (fd + 1, &fds, NULL, NULL, &tv);

if (-1 == r) {

if (EINTR == errno)

continue;

errno_exit ("select");

}

if (0 == r) {

fprintf (stderr, "select timeoutn");

exit (EXIT_FAILURE);

}

if (read_frame ())

break;

}

}

}

static void stop_capturing (void)

{

enum v4l2_buf_type type;

type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

if (-1 == xioctl (fd, VIDIOC_STREAMOFF, &type))

errno_exit ("VIDIOC_STREAMOFF");

}

static void start_capturing (void)

{

unsigned int i;

enum v4l2_buf_type type;

for (i = 0; i < n_buffers; ++i) {

struct v4l2_buffer buf;

CLEAR (buf);

buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

buf.memory = V4L2_MEMORY_MMAP;

buf.index = i;

if (-1 == xioctl (fd, VIDIOC_QBUF, &buf))

errno_exit ("VIDIOC_QBUF");

}

type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

if (-1 == xioctl (fd, VIDIOC_STREAMON, &type))

errno_exit ("VIDIOC_STREAMON");

}

static void uninit_device (void)

{

unsigned int i;

for (i = 0; i < n_buffers; ++i)

if (-1 == munmap (buffers[i].start, buffers[i].length))

errno_exit ("munmap");

if (-1 == munmap(fbp, screensize)) {

printf(" Error: framebuffer device munmap() failed.n");

exit (EXIT_FAILURE) ;

}

free (buffers);

}

static void init_mmap (void)

{

struct v4l2_requestbuffers req;

//mmap framebuffer

fbp = (char *)mmap(NULL,screensize,PROT_READ | PROT_WRITE,MAP_SHARED ,fbfd, 0);

if ((int)fbp == -1) {

printf("Error: failed to map framebuffer device to memory.n");

exit (EXIT_FAILURE) ;

}

memset(fbp, 0, screensize);

CLEAR (req);

req.count = 4;

req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

req.memory = V4L2_MEMORY_MMAP;

if (-1 == xioctl (fd, VIDIOC_REQBUFS, &req)) {

if (EINVAL == errno) {

fprintf (stderr, "%s does not support memory mappingn", dev_name);

exit (EXIT_FAILURE);

} else {

errno_exit ("VIDIOC_REQBUFS");

}

}

if (req.count < 4) {    //if (req.count < 2)

fprintf (stderr, "Insufficient buffer memory on %sn",dev_name);

exit (EXIT_FAILURE);

}

buffers = calloc (req.count, sizeof (*buffers));

if (!buffers) {

fprintf (stderr, "Out of memoryn");

exit (EXIT_FAILURE);

}

for (n_buffers = 0; n_buffers < req.count; ++n_buffers) {

struct v4l2_buffer buf;

CLEAR (buf);

buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

buf.memory = V4L2_MEMORY_MMAP;

buf.index = n_buffers;

if (-1 == xioctl (fd, VIDIOC_QUERYBUF, &buf))

errno_exit ("VIDIOC_QUERYBUF");

buffers[n_buffers].length = buf.length;

buffers[n_buffers].start =mmap (NULL,buf.length,PROT_READ | PROT_WRITE ,MAP_SHARED,fd, buf.m.offset);

if (MAP_FAILED == buffers[n_buffers].start)

errno_exit ("mmap");

}

}

static void init_device (void)

{

struct v4l2_capability cap;

struct v4l2_cropcap cropcap;

struct v4l2_crop crop;

struct v4l2_format fmt;

// Get fixed screen information

//得到固定屏幕的信息

if (-1==xioctl(fbfd, FBIOGET_FSCREENINFO, &finfo)) {

printf("Error reading fixed information.n");

exit (EXIT_FAILURE);

}

// Get variable screen information

//得到可变屏幕的信息

if (-1==xioctl(fbfd, FBIOGET_VSCREENINFO, &vinfo)) {

printf("Error reading variable information.n");

exit (EXIT_FAILURE);

}

screensize = vinfo.xres * vinfo.yres * vinfo.bits_per_pixel / 8;

//输出可变屏幕和固定屏幕的信息

printf("vinfo: xoffset:%d  yoffset:%d bits_per_pixel:%d xres:%d yres:%dn",vinfo.xoffset, vinfo.yoffset, vinfo.bits_per_pixel, vinfo.xres, vinfo.yres);

printf("finfo: line_length:%d  screensize:%ldn", finfo.line_length, screensize);

//获取camere的信息，复制到cap中

if (-1 == xioctl (fd, VIDIOC_QUERYCAP, &cap)) {

if (EINVAL == errno) {

fprintf (stderr, "%s is no V4L2 devicen",dev_name);

exit (EXIT_FAILURE);

} else {

errno_exit ("VIDIOC_QUERYCAP");

}

}

printf("cap.capabilities = %dn",cap.capabilities);

if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {

//#define V4L2_CAP_VIDEO_CAPTURE 0x00000001  /* Is a video capture device */

fprintf (stderr, "%s is no video capture devicen",dev_name);

exit (EXIT_FAILURE);

}

if (!(cap.capabilities & V4L2_CAP_STREAMING)) {

//#define V4L2_CAP_STREAMING              0x04000000  /* streaming I/O ioctls */

fprintf (stderr, "%s does not support streaming i/on",dev_name);

exit (EXIT_FAILURE);

}

CLEAR (cropcap);

cropcap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

//VIDIOC_CROPCAP：查询驱动的修剪能力

if (0 == xioctl (fd, VIDIOC_CROPCAP, &cropcap)) {

crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

crop.c = cropcap.defrect;

if (-1 == xioctl (fd, VIDIOC_S_CROP, &crop)) {

switch (errno) {

case EINVAL:

break;

default:

break;

}

}

}else {     }

CLEAR (fmt);

/*采集信号的type width height 帧格式*/

fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

fmt.fmt.pix.width = 320;

fmt.fmt.pix.height = 240;

fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;

//V4L2_PIX_FMT_JPEG;//V4L2_PIX_FMT_YUYV;

//  fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;

//VIDIOC_S_FMT：设置当前驱动的频捕获格式

if (-1 == xioctl (fd, VIDIOC_S_FMT, &fmt))

errno_exit ("VIDIOC_S_FMT");

init_mmap ();

}

static void close_device (void)

{

if (-1 == close (fd))

errno_exit ("close");

fd = -1;

close(fbfd);

}

static void open_device (void)

{

struct stat st;

if (-1 == stat (dev_name, &st)) {

fprintf (stderr, "Cannot identify '%s': %d, %sn",dev_name, errno, strerror (errno));

exit (EXIT_FAILURE);

}

if (!S_ISCHR (st.st_mode)) {

fprintf (stderr, "%s is no devicen", dev_name);

exit (EXIT_FAILURE);

}

//open framebuffer

fbfd = open("/dev/fb0", O_RDWR);

if (fbfd==-1) {

printf("Error: cannot open framebuffer device.n");

exit (EXIT_FAILURE);

}

//open camera

fd = open (dev_name, O_RDWR| O_NONBLOCK, 0);

if (-1 == fd) {

fprintf (stderr, "Cannot open '%s': %d, %sn",dev_name, errno, strerror (errno));

exit (EXIT_FAILURE);

}

}

static void usage (FILE * fp,int argc,char ** argv)

{

fprintf (fp,

"Usage: %s [options]nn"

"Options:n"

"-d | --device name Video device name [/dev/video]n"

"-h | --help Print this messagen"

"-t | --how long will display in secondsn"