#define CLEAR(x) memset(&(x), 0, sizeof(x))
struct buffer {
- void *start;
- size_t length;
+ void *start;
+ size_t length;
};
static void xioctl(int fh, int request, void *arg)
{
- int r;
+ int r;
- do {
- r = v4l2_ioctl(fh, request, arg);
- } while (r == -1 && ((errno == EINTR) || (errno == EAGAIN)));
+ do {
+ r = v4l2_ioctl(fh, request, arg);
+ } while (r == -1 && ((errno == EINTR) || (errno == EAGAIN)));
- if (r == -1) {
- fprintf(stderr, "error %d, %s\\n", errno, strerror(errno));
- exit(EXIT_FAILURE);
- }
+ if (r == -1) {
+ fprintf(stderr, "error %d, %s\\n", errno, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
}
int main(int argc, char **argv)
{
- struct v4l2_format fmt;
- struct v4l2_buffer buf;
- struct v4l2_requestbuffers req;
- enum v4l2_buf_type type;
- fd_set fds;
- struct timeval tv;
- int r, fd = -1;
- unsigned int i, n_buffers;
- char *dev_name = "/dev/video0";
- char out_name[256];
- FILE *fout;
- struct buffer *buffers;
-
- fd = v4l2_open(dev_name, O_RDWR | O_NONBLOCK, 0);
- if (fd < 0) {
- perror("Cannot open device");
- exit(EXIT_FAILURE);
- }
-
- CLEAR(fmt);
- fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
- fmt.fmt.pix.width = 640;
- fmt.fmt.pix.height = 480;
- fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
- fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
- xioctl(fd, VIDIOC_S_FMT, &fmt);
- if (fmt.fmt.pix.pixelformat != V4L2_PIX_FMT_RGB24) {
- printf("Libv4l didn't accept RGB24 format. Can't proceed.\\n");
- exit(EXIT_FAILURE);
- }
- if ((fmt.fmt.pix.width != 640) || (fmt.fmt.pix.height != 480))
- printf("Warning: driver is sending image at %dx%d\\n",
- fmt.fmt.pix.width, fmt.fmt.pix.height);
-
- CLEAR(req);
- req.count = 2;
- req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
- req.memory = V4L2_MEMORY_MMAP;
- xioctl(fd, VIDIOC_REQBUFS, &req);
-
- buffers = calloc(req.count, sizeof(*buffers));
- for (n_buffers = 0; n_buffers < req.count; ++n_buffers) {
- CLEAR(buf);
-
- buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
- buf.memory = V4L2_MEMORY_MMAP;
- buf.index = n_buffers;
-
- xioctl(fd, VIDIOC_QUERYBUF, &buf);
-
- buffers[n_buffers].length = buf.length;
- buffers[n_buffers].start = v4l2_mmap(NULL, buf.length,
- PROT_READ | PROT_WRITE, MAP_SHARED,
- fd, buf.m.offset);
-
- if (MAP_FAILED == buffers[n_buffers].start) {
- perror("mmap");
- exit(EXIT_FAILURE);
- }
- }
-
- for (i = 0; i < n_buffers; ++i) {
- CLEAR(buf);
- buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
- buf.memory = V4L2_MEMORY_MMAP;
- buf.index = i;
- xioctl(fd, VIDIOC_QBUF, &buf);
- }
- type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-
- xioctl(fd, VIDIOC_STREAMON, &type);
- for (i = 0; i < 20; i++) {
- do {
- FD_ZERO(&fds);
- FD_SET(fd, &fds);
-
- /* Timeout. */
- tv.tv_sec = 2;
- tv.tv_usec = 0;
-
- r = select(fd + 1, &fds, NULL, NULL, &tv);
- } while ((r == -1 && (errno = EINTR)));
- if (r == -1) {
- perror("select");
- return errno;
- }
-
- CLEAR(buf);
- buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
- buf.memory = V4L2_MEMORY_MMAP;
- xioctl(fd, VIDIOC_DQBUF, &buf);
-
- sprintf(out_name, "out%03d.ppm", i);
- fout = fopen(out_name, "w");
- if (!fout) {
- perror("Cannot open image");
- exit(EXIT_FAILURE);
- }
- fprintf(fout, "P6\\n%d %d 255\\n",
- fmt.fmt.pix.width, fmt.fmt.pix.height);
- fwrite(buffers[buf.index].start, buf.bytesused, 1, fout);
- fclose(fout);
-
- xioctl(fd, VIDIOC_QBUF, &buf);
- }
-
- type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
- xioctl(fd, VIDIOC_STREAMOFF, &type);
- for (i = 0; i < n_buffers; ++i)
- v4l2_munmap(buffers[i].start, buffers[i].length);
- v4l2_close(fd);
-
- return 0;
+ struct v4l2_format fmt;
+ struct v4l2_buffer buf;
+ struct v4l2_requestbuffers req;
+ enum v4l2_buf_type type;
+ fd_set fds;
+ struct timeval tv;
+ int r, fd = -1;
+ unsigned int i, n_buffers;
+ char *dev_name = "/dev/video0";
+ char out_name[256];
+ FILE *fout;
+ struct buffer *buffers;
+
+ fd = v4l2_open(dev_name, O_RDWR | O_NONBLOCK, 0);
+ if (fd < 0) {
+ perror("Cannot open device");
+ exit(EXIT_FAILURE);
+ }
+
+ CLEAR(fmt);
+ fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ fmt.fmt.pix.width = 640;
+ fmt.fmt.pix.height = 480;
+ fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
+ fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
+ xioctl(fd, VIDIOC_S_FMT, &fmt);
+ if (fmt.fmt.pix.pixelformat != V4L2_PIX_FMT_RGB24) {
+ printf("Libv4l didn't accept RGB24 format. Can't proceed.\\n");
+ exit(EXIT_FAILURE);
+ }
+ if ((fmt.fmt.pix.width != 640) || (fmt.fmt.pix.height != 480))
+ printf("Warning: driver is sending image at %dx%d\\n",
+ fmt.fmt.pix.width, fmt.fmt.pix.height);
+
+ CLEAR(req);
+ req.count = 2;
+ req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ req.memory = V4L2_MEMORY_MMAP;
+ xioctl(fd, VIDIOC_REQBUFS, &req);
+
+ buffers = calloc(req.count, sizeof(*buffers));
+ for (n_buffers = 0; n_buffers < req.count; ++n_buffers) {
+ CLEAR(buf);
+
+ buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ buf.memory = V4L2_MEMORY_MMAP;
+ buf.index = n_buffers;
+
+ xioctl(fd, VIDIOC_QUERYBUF, &buf);
+
+ buffers[n_buffers].length = buf.length;
+ buffers[n_buffers].start = v4l2_mmap(NULL, buf.length,
+ PROT_READ | PROT_WRITE, MAP_SHARED,
+ fd, buf.m.offset);
+
+ if (MAP_FAILED == buffers[n_buffers].start) {
+ perror("mmap");
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ for (i = 0; i < n_buffers; ++i) {
+ CLEAR(buf);
+ buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ buf.memory = V4L2_MEMORY_MMAP;
+ buf.index = i;
+ xioctl(fd, VIDIOC_QBUF, &buf);
+ }
+ type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+ xioctl(fd, VIDIOC_STREAMON, &type);
+ for (i = 0; i < 20; i++) {
+ do {
+ FD_ZERO(&fds);
+ FD_SET(fd, &fds);
+
+ /* Timeout. */
+ tv.tv_sec = 2;
+ tv.tv_usec = 0;
+
+ r = select(fd + 1, &fds, NULL, NULL, &tv);
+ } while ((r == -1 && (errno = EINTR)));
+ if (r == -1) {
+ perror("select");
+ return errno;
+ }
+
+ CLEAR(buf);
+ buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ buf.memory = V4L2_MEMORY_MMAP;
+ xioctl(fd, VIDIOC_DQBUF, &buf);
+
+ sprintf(out_name, "out%03d.ppm", i);
+ fout = fopen(out_name, "w");
+ if (!fout) {
+ perror("Cannot open image");
+ exit(EXIT_FAILURE);
+ }
+ fprintf(fout, "P6\\n%d %d 255\\n",
+ fmt.fmt.pix.width, fmt.fmt.pix.height);
+ fwrite(buffers[buf.index].start, buf.bytesused, 1, fout);
+ fclose(fout);
+
+ xioctl(fd, VIDIOC_QBUF, &buf);
+ }
+
+ type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ xioctl(fd, VIDIOC_STREAMOFF, &type);
+ for (i = 0; i < n_buffers; ++i)
+ v4l2_munmap(buffers[i].start, buffers[i].length);
+ v4l2_close(fd);
+
+ return 0;
}
projects / deliverable / linux.git / blobdiff