求助,关于write_jpeg问题

听海拉拉 2010-08-12 02:52:41

/* 涓嬮潰鏄竴涓畬鏁寸殑绋嬪簭 test.c
* gcc test.c -o test -ljpeg
*/

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <errno.h>
#include <linux/videodev.h>

#include <jpeglib.h>

#define WIDTH 320
#define HEIGHT 240
#define V4L_DEVICE "/dev/video0"

int main()
{

unsigned char* buf;
int i,j;
int fd;
int re;

struct video_capability vcap;
struct video_channel vc;
struct video_mbuf mbuf;
struct video_mmap mm;

fd = open(V4L_DEVICE, O_RDWR);
if(fd<=0)
{
perror("open");
exit(1);
}

if(ioctl(fd, VIDIOCGCAP, &vcap)<0)
{
perror("VIDIOCGCAP");
exit(1);
}

fprintf(stderr,"Video Capture Device Name : %s\n",vcap.name);

for(i=0;i<vcap.channels;i++)
{
vc.channel = i;
if(ioctl(fd, VIDIOCGCHAN, &vc)<0)
{
perror("VIDIOCGCHAN");
exit(1);
}

fprintf(stderr,"Video Source (%d) Name : %s\n",i, vc.name);
}

vc.channel =1;
vc.norm=1;

if(ioctl(fd, VIDIOCSCHAN, &vc) < 0)
{
perror("VIDIOCSCHAN");
exit(1);
}

if(ioctl(fd, VIDIOCGMBUF, &mbuf) < 0)
{
perror("VIDIOCGMBUF");
exit(1);
}
else
{
perror("henhao");
}
fprintf(stderr,"the frames number is %d\n",mbuf.frames);

buf = (unsigned char*)mmap(0, mbuf.size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
if((int)buf < 0)
{
perror("mmap");
exit(1);
}
mm.frame = 0;
mm.height = HEIGHT;
mm.width = WIDTH;
mm.format = VIDEO_PALETTE_RGB24;

if(ioctl(fd, VIDIOCMCAPTURE, &mm)<0)
{
perror("VIDIOCMCAPTURE");
exit(1);
}

if(ioctl(fd, VIDIOCSYNC, &mm.frame)<0)
{
perror("VIDIOCSYNC");
exit(1);
}

if(-1 == (write_jpeg("./pic001.jpeg",buf,75,WIDTH,HEIGHT,0)))
{
printf("write_jpeg error\n");
exit(1);
}

munmap(buf,mbuf.size);
close(fd);
}
怎么找不到write_jpeg？
acer@ubuntu:~$ gcc test.c -o test -ljpeg
/tmp/ccIvsg0u.o: In function `main':
test.c:(.text+0x352): undefined reference to `write_jpeg'
collect2: ld returned 1 exit status

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