tTh
/
FloatImg
2
2
Fork 1
Code Issues 2 Pull Requests Releases Wiki Activity
Browse Source

videograb : first step

master
Tonton Th 3 years ago
parent
f0f8daa0fb
commit
c054054ee5
5 changed files with 355 additions and 9 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 2
      .gitignore
  2. 11
      v4l2/Makefile
  3. 317
      v4l2/funcs.c
  4. 7
      v4l2/funcs.h
  5. 27
      v4l2/t.c

2
.gitignore vendored
Unescape View File

@ -9,6 +9,8 @@ gmon.out @@ -9,6 +9,8 @@ gmon.out
*.fimg
essai
*/*.ps
v4l2/t
v4l2/capture
v4l2/*.o

11
v4l2/Makefile
Unescape View File

@ -3,13 +3,14 @@ @@ -3,13 +3,14 @@
COPT = -Wall -fpic -g -DDEBUG_LEVEL=1
DEPS = ../floatimg.h ../libfloatimg.a Makefile
funcs.o: funcs.c funcs.h Makefile
gcc ${COPT} -c $<
t: t.c Makefile ${DEPS} funcs.o
gcc ${COPT} $< funcs.o ../libfloatimg.a -o $@
t: t.c Makefile ${DEPS}
gcc ${COPT} $< ../libfloatimg.a -o $@
# --------
# extern things
# ---------------
# external things
capture: capture.c Makefile
gcc -Wall $< -o $@

317
v4l2/funcs.c
Unescape View File

@ -0,0 +1,317 @@ @@ -0,0 +1,317 @@
/*
* V4L2 functions - ugly source code
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h> /* low-level i/o */
#include <unistd.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <linux/videodev2.h>
/* --------------------------------------------------------------------- */
extern int verbosity;
enum io_method {
IO_METHOD_READ,
IO_METHOD_MMAP,
IO_METHOD_USERPTR,
};
struct buffer {
void *start;
size_t length;
};
static char *dev_name;
static enum io_method io = IO_METHOD_MMAP;
static int fd = -1;
struct buffer *buffers;
static unsigned int n_buffers;
static int out_buf;
static int force_format;
static int frame_count = 70;
static void errno_exit(const char *s)
{
fprintf(stderr, "%s error %d, %s\n", s, errno, strerror(errno));
exit(EXIT_FAILURE);
}
static int xioctl(int fh, int request, void *arg)
{
int r;
do {
r = ioctl(fh, request, arg);
} while (-1 == r && EINTR == errno);
return r;
}
/* --------------------------------------------------------------------- */
/*
*
*/
int open_device(char *device)
{
struct stat st;
if (-1 == stat(device, &st)) {
fprintf(stderr, "Cannot identify '%s': %d, %s\n",
device, errno, strerror(errno));
exit(EXIT_FAILURE);
}
if (!S_ISCHR(st.st_mode)) {
fprintf(stderr, "%s is no device\n", device);
exit(EXIT_FAILURE);
}
fd = open(device, O_RDWR /* required */ | O_NONBLOCK, 0);
if (-1 == fd) {
fprintf(stderr, "Cannot open '%s': %d, %s\n",
device, errno, strerror(errno));
exit(EXIT_FAILURE);
}
dev_name = strdup(device); /* XXX */
return fd;
}
/* --------------------------------------------------------------------- */
static void init_read(unsigned int buffer_size)
{
buffers = calloc(1, sizeof(*buffers));
if (!buffers) {
fprintf(stderr, "Out of memory\n");
exit(EXIT_FAILURE);
}
buffers[0].length = buffer_size;
buffers[0].start = malloc(buffer_size);
if (!buffers[0].start) {
fprintf(stderr, "Out of memory\n");
exit(EXIT_FAILURE);
}
}
static void init_mmap(void)
{
struct v4l2_requestbuffers req;
memset(&req, 0, sizeof(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", dev_name);
exit(EXIT_FAILURE);
} else {
errno_exit("VIDIOC_REQBUFS");
}
}
if (req.count < 2) {
fprintf(stderr, "Insufficient buffer memory on %s\n",
dev_name);
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;
memset(&buf, 0, sizeof(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");
}
}
static void init_userp(unsigned int buffer_size)
{
struct v4l2_requestbuffers req;
memset(&req, 0, sizeof(req));
req.count = 4;
req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
req.memory = V4L2_MEMORY_USERPTR;
if (-1 == xioctl(fd, VIDIOC_REQBUFS, &req)) {
if (EINVAL == errno) {
fprintf(stderr, "%s does not support "
"user pointer i/o\n", dev_name);
exit(EXIT_FAILURE);
} else {
errno_exit("VIDIOC_REQBUFS");
}
}
buffers = calloc(4, sizeof(*buffers));
if (!buffers) {
fprintf(stderr, "Out of memory\n");
exit(EXIT_FAILURE);
}
for (n_buffers = 0; n_buffers < 4; ++n_buffers) {
buffers[n_buffers].length = buffer_size;
buffers[n_buffers].start = malloc(buffer_size);
if (!buffers[n_buffers].start) {
fprintf(stderr, "Out of memory\n");
exit(EXIT_FAILURE);
}
}
}
/* --------------------------------------------------------------------- */
int init_device(int notused)
{
struct v4l2_capability cap;
struct v4l2_cropcap cropcap;
struct v4l2_crop crop;
struct v4l2_format fmt;
unsigned int min;
#if DEBUG_LEVEL
fprintf(stderr, ">>> %s ( %d )\n", __func__, notused);
#endif
if (-1 == xioctl(fd, VIDIOC_QUERYCAP, &cap)) {
if (EINVAL == errno) {
fprintf(stderr, "%s is no V4L2 device\n", dev_name);
exit(EXIT_FAILURE);
} else {
errno_exit("VIDIOC_QUERYCAP");
}
}
if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
fprintf(stderr, "%s is no video capture device\n", dev_name);
exit(EXIT_FAILURE);
}
switch (io) {
case IO_METHOD_READ:
if (!(cap.capabilities & V4L2_CAP_READWRITE)) {
fprintf(stderr, "%s do not support read i/o\n", dev_name);
exit(EXIT_FAILURE);
}
if (verbosity) fprintf(stderr, "%s io method read OK\n", __func__);
break;
case IO_METHOD_MMAP:
case IO_METHOD_USERPTR:
if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
fprintf(stderr, "%s do not support streaming i/o\n", dev_name);
exit(EXIT_FAILURE);
}
if (verbosity) fprintf(stderr, "%s io mmap/userptr OK\n", __func__);
break;
} /* end switch */
/* Select video input, video standard and tune here. */
memset(&cropcap, 0, sizeof(cropcap));
cropcap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (0 == xioctl(fd, VIDIOC_CROPCAP, &cropcap)) {
crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
crop.c = cropcap.defrect; /* reset to default */
if (-1 == xioctl(fd, VIDIOC_S_CROP, &crop)) {
switch (errno) {
case EINVAL:
/* Cropping not supported. */
break;
default:
/* Errors ignored. */
break;
}
}
} else {
/* Errors ignored. */
}
memset(&fmt, 0, sizeof(fmt)); // CLEAR(fmt);
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (force_format) {
fmt.fmt.pix.width = 640;
fmt.fmt.pix.height = 480;
fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
if (-1 == xioctl(fd, VIDIOC_S_FMT, &fmt))
errno_exit("VIDIOC_S_FMT");
/* Note VIDIOC_S_FMT may change width and height. */
} else {
/* Preserve original settings as set by v4l2-ctl for example */
if (-1 == xioctl(fd, VIDIOC_G_FMT, &fmt))
errno_exit("VIDIOC_G_FMT");
}
/* 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;
switch (io) {
case IO_METHOD_READ:
init_read(fmt.fmt.pix.sizeimage);
break;
case IO_METHOD_MMAP:
init_mmap();
break;
case IO_METHOD_USERPTR:
init_userp(fmt.fmt.pix.sizeimage);
break;
}
return 0;
}

7
v4l2/funcs.h
Unescape View File

@ -0,0 +1,7 @@ @@ -0,0 +1,7 @@
/*
* V4L2 functions - header file
*/
int open_device(char *dev_name);
int init_device(int notused);

27
v4l2/t.c
Unescape View File

@ -8,10 +8,26 @@ @@ -8,10 +8,26 @@
#include <math.h>
#include <string.h>
#include "funcs.h"
#include "floatimg.h"
int verbosity;
/* --------------------------------------------------------------------- */
int essai(char *dev, int k)
{
int vfd, foo;
fprintf(stderr, ">>> %s ( '%s' %d )\n", __func__, dev, k);
vfd = open_device(dev);
fprintf(stderr, "\topen %s -> %d\n", dev, vfd);
foo = init_device(0);
fprintf(stderr, "\tinit -> %d\n", foo);
return k;
}
/* --------------------------------------------------------------------- */
void help(int k)
{
@ -23,16 +39,16 @@ puts("\t-v\tincrease verbosity"); @@ -23,16 +39,16 @@ puts("\t-v\tincrease verbosity");
exit(0);
}
/* --------------------------------------------------------------------- */
int main(int argc, char *argv[])
{
int foo, opt;
int W = 800, H = 600;
double tb;
char *device = "/dev/video0";
int K = 0;
while ((opt = getopt(argc, argv, "hK:v")) != -1) {
while ((opt = getopt(argc, argv, "d:hK:v")) != -1) {
switch(opt) {
case 'd': device = optarg; break;
case 'h': help(0); break;
case 'K': K = atol(optarg); break;
case 'v': verbosity++; break;
@ -41,6 +57,9 @@ while ((opt = getopt(argc, argv, "hK:v")) != -1) { @@ -41,6 +57,9 @@ while ((opt = getopt(argc, argv, "hK:v")) != -1) {
if (verbosity) fimg_print_version(0);
foo = essai(device, K);
fprintf(stderr, "\tessai -> %d\n", foo);
return 0;
}
/* --------------------------------------------------------------------- */

Write Preview
Loading…
Cancel
Save