s5pv210 jpeg硬件编码
做qt摄像头程序的时候发现yuv转rgb然后显示 效果很不好 所以考虑转jpg后显示 但是使用libjpeg发现格式怎么设置都不对 之前在android上使用的函数拿过来都不能直接使用 所以还是研究硬编吧 这里使用的是广州斯道ICOOL210开发板 内核版本linux2.6.35
前面的一些流程我就不上代码了标准的v4l2流程 格式设置为V4L2_PIX_FMT_YUYV即yuv422格式 宽 640 高 480 主要是在获取到yuv数据后转成jpg然后保存 摄像头的程序网上有大把的例子 我这里比较乱我只放增加的函数了
首先把内核里的s3c-jpeg.h拷贝过来 这里是我的头文件
/* * v4l2.h * Author: hclydao */ #ifndef V4L2_H_ #define V4L2_H_ #include "s3c-jpeg.h" #define CLEAR(x) memset (&(x), 0, sizeof (x)) void errno_exit(const char* s); int xioctl(int fd, int request, void* argp); void deviceOpen(void); int select_input(int input); void deviceInit(void); void mmapInit(void); void captureStart(void); void mainLoop(void); unsigned char* frameRead(void); void imageProcess(const void* p); static void deviceUninit(void); static int jfd; unsigned char *ydata; static int name = 0; struct jpg_args mArgs; unsigned char *pInBuf; int jpeg_init(void); int test; int jpg_enc(const void *p,int len); #endif /* V4L2_H_ */</span>
我还是上代码吧 前面的这些流程完全都是标准的 网上的说明很详细 这里就不说明了
<span style="font-size:14px;">/*
* v4l2.c
* Author: hclydao
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <getopt.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <malloc.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <asm/types.h>
#include <linux/videodev2.h>
#include <jpeglib.h>
#include <linux/fb.h>
#include "v4l2.h"
struct buffer {
void * start;
size_t length;
};
int fd = -1;
struct buffer * buffers = NULL;
static unsigned int n_buffers = 0;
// global settings
static unsigned int width = 640;
static unsigned int height = 480;
static char* deviceName = "/dev/video0";
static char* jpgdev = "/dev/s3c-jpg";
static int fb_bpp;
static int cam_fp = -1;
static int fb_fp = -1;
static char *fb_addr = NULL;
void deviceOpen(void)
{
struct stat st;
// stat file
if (-1 == stat(deviceName, &st)) {
fprintf(stderr, "Cannot identify '%s': %d, %s\n", deviceName, errno, strerror (errno));
exit(EXIT_FAILURE);
}
// check if its device
if (!S_ISCHR (st.st_mode)) {
fprintf(stderr, "%s is no device\n", deviceName);
exit(EXIT_FAILURE);
}
// open device
fd = open(deviceName, O_RDWR /* required */ | O_NONBLOCK, 0);
// check if opening was successfull
if (-1 == fd) {
fprintf(stderr, "Cannot open '%s': %d, %s\n", deviceName, errno, strerror (errno));
exit(EXIT_FAILURE);
}
}
int select_input(int input)
{
int ret;
ret = xioctl(fd, VIDIOC_S_INPUT, &input);
if (ret) {
printf("xioctl VIDIOC_S_INPUT failed errno(%d)\n", errno);
}
return ret;
}
/**
initialize device
*/
void deviceInit(void)
{
struct v4l2_capability cap;
struct v4l2_format fmt;
unsigned int min;
if (-1 == xioctl(fd, VIDIOC_QUERYCAP, &cap)) {
if (EINVAL == errno) {
fprintf(stderr, "%s is no V4L2 device\n",deviceName);
exit(EXIT_FAILURE);
} else {
errno_exit("VIDIOC_QUERYCAP");
}
}
if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE))
{
fprintf(stderr, "%s is no video capture device\n",deviceName);
exit(EXIT_FAILURE);
}
if (!(cap.capabilities & V4L2_CAP_STREAMING))
{
fprintf(stderr, "%s does not support streaming i/o\n",deviceName);
exit(EXIT_FAILURE);
}
CLEAR (fmt);
// v4l2_format
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = width;
fmt.fmt.pix.height = height;
fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;//V4L2_PIX_FMT_RGB32;
fmt.fmt.pix.field = V4L2_FIELD_NONE;//V4L2_FIELD_INTERLACED;//V4L2_FIELD_NONE;
fmt.fmt.pix.priv = 1;
if (-1 == xioctl(fd, VIDIOC_S_FMT, &fmt))
errno_exit("VIDIOC_S_FMT");
/* Note VIDIOC_S_FMT may change width and height. */
if (width != fmt.fmt.pix.width) {
width = fmt.fmt.pix.width;
fprintf(stderr,"Image width set to %i by device %s.\n",width,deviceName);
}
if (height != fmt.fmt.pix.height) {
height = fmt.fmt.pix.height;
fprintf(stderr,"Image height set to %i by device %s.\n",height,deviceName);
}
/* Buggy driver paranoia. */
min = fmt.fmt.pix.width * 2;
if (fmt.fmt.pix.bytesperline < min)
fmt.fmt.pix.bytesperline = min;
min = fmt.fmt.pix.bytesperline * fmt.fmt.pix.height;
if (fmt.fmt.pix.sizeimage < min)
fmt.fmt.pix.sizeimage = min;
mmapInit();
}
void mmapInit(void)
{
struct v4l2_requestbuffers req;
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 mapping\n", deviceName);
exit(EXIT_FAILURE);
} else {
errno_exit("VIDIOC_REQBUFS");
}
}
if (req.count < 2) {
fprintf(stderr, "Insufficient buffer memory on %s\n", deviceName);
exit(EXIT_FAILURE);
}
buffers = calloc(req.count, sizeof(*buffers));
if (!buffers) {
fprintf(stderr, "Out of memory\n");
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 /* start anywhere */, buf.length, PROT_READ | PROT_WRITE /* required */, MAP_SHARED /* recommended */, fd, buf.m.offset);
if (MAP_FAILED == buffers[n_buffers].start)
errno_exit("mmap");
}
}
void captureStart(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");
}
void mainLoop(void)
{
unsigned int count;
count = 1;
while (count-- > 0) {
for (;;) {
fd_set fds;
struct timeval tv;
int r;
FD_ZERO(&fds);
FD_SET(fd, &fds);
/* Timeout. */
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 timeout\n");
exit(EXIT_FAILURE);
}
if (frameRead())
break;
}
}
}
unsigned char* frameRead(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);
//imageProcess(buffers[buf.index].start);
if(test > 44)//放弃前面的数据
jpg_enc(buffers[buf.index].start,buffers[buf.index].length);
if (-1 == xioctl(fd, VIDIOC_QBUF, &buf))
errno_exit("VIDIOC_QBUF");
return (unsigned char*)buffers[buf.index].start;
}
void imageProcess(const void* p)
{
unsigned char* src = (unsigned char*)p;
memcpy(&fb_addr[0],src,width*height*4);
}
void deviceUninit(void)
{
unsigned int i;
for (i = 0; i < n_buffers; ++i)
{
if (-1 == munmap (buffers[i].start, buffers[i].length))
errno_exit("munmap");
}
free(buffers);
}
void errno_exit(const char* s)
{
fprintf(stderr, "%s error %d, %s\n", s, errno, strerror (errno));
exit(EXIT_FAILURE);
}
int xioctl(int fd, int request, void* argp)
{
int r;
do r = ioctl(fd, request, argp);
while (-1 == r && EINTR == errno);
return r;
}
int jpg_enc(const void *p,int len)//编码函数
{
FILE *fp;
char tmp[20];
int err;
enum jpg_return_status ret = JPG_FAIL;
unsigned char* src = (unsigned char*)p;
memcpy(pInBuf, src, len);
ret = (enum jpg_return_status)ioctl(jfd, IOCTL_JPG_ENCODE, &mArgs);
if (ret != JPG_SUCCESS) {
printf("++++++++IOCTL_JPG_ENCODE failed\n");
return -1;
}
mArgs.out_buf = (char *)ioctl(jfd, IOCTL_JPG_GET_STRBUF, mArgs.mapped_addr);
sprintf(tmp, "%d.jpg", name++);
fp = fopen(tmp,"wb");
if(fp < 0) {
printf("+++++++++++=open file %s failed\n",tmp);
return -1;
}
err = fwrite(mArgs.out_buf,sizeof(char),mArgs.enc_param->file_size,fp);
if(err < 0) {
printf("+++++++++++=write data failed\n");
return -1;
}
fclose(fp);
return mArgs.enc_param->file_size;
}
int jpeg_init(void)//jpg初始化
{
jfd = open(jpgdev,O_RDWR);
if(jfd < 0) {
printf("++++open jfd failed\n");
return -1;
}
mArgs.mapped_addr = mmap(0,640*480*4,PROT_READ | PROT_WRITE,MAP_SHARED, jfd, 0);
if(mArgs.mapped_addr == MAP_FAILED) {
printf("++++addr_base mmap failed\n");
return -1;
}
mArgs.enc_param = (struct jpg_enc_proc_param *)malloc(sizeof(struct jpg_enc_proc_param));
if(mArgs.enc_param == NULL) {
printf("++++enc_param malloc failed\n");
return -1;
}
memset(mArgs.enc_param,0,sizeof(struct jpg_enc_proc_param));
mArgs.enc_param->sample_mode = JPG_422;
mArgs.enc_param->enc_type = JPG_MAIN;
mArgs.enc_param->in_format = JPG_MODESEL_YCBCR;
mArgs.enc_param->quality = JPG_QUALITY_LEVEL_1;
mArgs.enc_param->width = 640;
mArgs.enc_param->height = 480;
pInBuf = (unsigned char *)ioctl(jfd, IOCTL_JPG_GET_FRMBUF, mArgs.mapped_addr);
if (pInBuf == NULL) {
printf("+++++++=JPEG input buffer is NULL!!\n");
return -1;
}
}
下面是主函数
/*
* main.c
*
* Created on: Aug 4, 2011
* Author: gavin
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <getopt.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <malloc.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <asm/types.h>
#include <linux/videodev2.h>
#include <jpeglib.h>
#include <linux/fb.h>
#include "v4l2.h"
int main()
{
jpeg_init();
deviceOpen();
select_input(0);
deviceInit();
captureStart();
for(test=0;test<50;test++)
{
mainLoop();
}
return 1;
}
不要前面的一些帧 前面的有可能会是全绿的 以下是效果图
测试完成开始修改qt工程
工程下载地址:http://download.csdn.net/detail/hclydao/8217081
============================================
作者：hclydao
http://blog.csdn.net/hclydao
版权没有，但是转载请保留此段声明
============================================