Skip to content

Commit

Permalink
[libuvc] fix issue #21
Browse files Browse the repository at this point in the history
  • Loading branch information
@gozfree
gozfree committed Jan 5, 2019
1 parent 657c88c commit f567e55
Show file tree
Hide file tree
Showing 3 changed files with 103 additions and 11 deletions.
87 changes: 78 additions & 9 deletions libuvc/libuvc.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -66,9 +66,11 @@ struct v4l2_ctx {
struct iovec buf[MAX_V4L_BUF];
int buf_index;
int req_count;
bool qbuf_done;
struct v4l2_capability cap;
uint32_t ctrl_flags;
struct v4l2_queryctrl controls[MAX_V4L2_CID];
struct uvc_ctx *parent;
};

static int v4l2_get_cap(struct v4l2_ctx *vc)
Expand Down Expand Up @@ -120,11 +122,10 @@ static char *v4l2_fourcc_parse(char *buf, int len, uint32_t pix)
if (len < 5) {
return NULL;
}
snprintf(buf, len, "%c%c%c%c",
(pix&0x000000FF),
(pix&0x0000FF00)>>8,
(pix&0x00FF0000)>>16,
(pix&0xFF000000)>>24);
snprintf(buf, len, "%c%c%c%c", (pix&0x000000FF),
(pix&0x0000FF00)>>8,
(pix&0x00FF0000)>>16,
(pix&0xFF000000)>>24);
return buf;
}

Expand Down Expand Up @@ -185,14 +186,12 @@ static void v4l2_get_cid(struct v4l2_ctx *vc)
qctrl = &vc->controls[i];
qctrl->id = v4l2_cid_supported[i];
if (-1 == ioctl(vc->fd, VIDIOC_QUERYCTRL, qctrl)) {
//printf("\t%s is not supported!\n", qctrl->name);
continue;
}
vc->ctrl_flags |= 1 << i;
memset(&control, 0, sizeof (control));
control.id = v4l2_cid_supported[i];
if (-1 == ioctl(vc->fd, VIDIOC_G_CTRL, &control)) {
//printf("ioctl VIDIOC_G_CTRL %s failed!\n", qctrl->name);
continue;
}
printf("\t%s, range: [%d, %d], default: %d, current: %d\n",
Expand Down Expand Up @@ -229,7 +228,6 @@ static int v4l2_set_format(struct v4l2_ctx *vc)
v4l2_fourcc_parse(pixel, sizeof(pixel), V4L2_PIX_FMT_YUYV));
}
if (vc->width > 0 || vc->height > 0) {
//set v4l2 pixel format
pix->width = vc->width;
pix->height = vc->height;
} else {
Expand Down Expand Up @@ -287,6 +285,7 @@ static int v4l2_req_buf(struct v4l2_ctx *vc)
return -1;
}
}
vc->qbuf_done = true;
//stream on
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (-1 == ioctl(vc->fd, VIDIOC_STREAMON, &type)) {
Expand Down Expand Up @@ -345,18 +344,27 @@ static int v4l2_buf_enqueue(struct v4l2_ctx *vc)
.index = vc->buf_index
};

if (vc->qbuf_done) {
return 0;
}
if (-1 == ioctl(vc->fd, VIDIOC_QBUF, &buf)) {
printf("%s ioctl(VIDIOC_QBUF) failed: %d\n", __func__, errno);
return -1;
}
vc->qbuf_done = true;
return 0;
}

static int v4l2_buf_dequeue(struct v4l2_ctx *vc, struct frame *f)
{
struct v4l2_buffer buf;
memset(&buf, 0, sizeof(buf));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
if (!vc->qbuf_done) {
printf("v4l2 need VIDIOC_QBUF first!\n");
return -1;
}
while (1) {
if (-1 == ioctl(vc->fd, VIDIOC_DQBUF, &buf)) {
printf("%s ioctl(VIDIOC_DQBUF) failed: %d\n", __func__, errno);
Expand All @@ -368,7 +376,9 @@ static int v4l2_buf_dequeue(struct v4l2_ctx *vc, struct frame *f)
}
break;
}
vc->qbuf_done = false;
vc->buf_index = buf.index;
memcpy(&vc->parent->timestamp, &buf.timestamp, sizeof(struct timeval));
f->index = buf.index;
f->buf.iov_base = vc->buf[buf.index].iov_base;
f->buf.iov_len = buf.bytesused;
Expand Down Expand Up @@ -432,6 +442,7 @@ struct uvc_ctx *uvc_open(const char *dev, int width, int height)
printf("v4l2_open %s failed!\n", dev);
goto failed;
}
vc->parent = uvc;
uvc->width = width;
uvc->height = height;
uvc->opaque = vc;
Expand All @@ -444,10 +455,68 @@ struct uvc_ctx *uvc_open(const char *dev, int width, int height)
int uvc_read(struct uvc_ctx *uvc, void *buf, size_t len)
{
struct v4l2_ctx *vc = (struct v4l2_ctx *)uvc->opaque;
v4l2_write(vc);
if (-1 == v4l2_write(vc)) {
return -1;
}
return v4l2_read(vc, buf, len);
}

static int v4l2_set_control(struct v4l2_ctx *vc, uint32_t cid, int value)
{
int i;
struct v4l2_control control;
int ret = -1;
for (i = 0; v4l2_cid_supported[i]; i++) {
if (!(vc->ctrl_flags & (1 << i))) {
continue;
}
if (cid != v4l2_cid_supported[i]) {
continue;
}
struct v4l2_queryctrl *ctrl = &vc->controls[i];

memset(&control, 0, sizeof (control));
control.id = v4l2_cid_supported[i];
switch (ctrl->type) {
case V4L2_CTRL_TYPE_INTEGER://0~255
value = control.value =
(value * (ctrl->maximum - ctrl->minimum) / 256) + ctrl->minimum;
ret = ioctl(vc->fd, VIDIOC_S_CTRL, &control);
break;

case V4L2_CTRL_TYPE_BOOLEAN:
value = control.value = value ? 1 : 0;
ret = ioctl(vc->fd, VIDIOC_S_CTRL, &control);
break;

default:
printf("control type not supported yet");
return -1;
}
printf("setting %s to %d\n", ctrl->name, value);
}
return ret;
}

int uvc_ioctl(struct uvc_ctx *c, uint32_t cmd, void *buf, int len)
{
struct v4l2_ctx *vc = (struct v4l2_ctx *)c->opaque;
struct video_ctrl *vctrl;
switch (cmd) {
case UVC_GET_CAP:
v4l2_get_cap(vc);
break;
case UVC_SET_CTRL:
vctrl = (struct video_ctrl *)buf;
v4l2_set_control(vc, vctrl->cmd, vctrl->val);
break;
default:
printf("cmd %d not supported yet!\n", cmd);
break;
}
return 0;
}

void uvc_close(struct uvc_ctx *uvc)
{
if (!uvc) {
Expand Down
21 changes: 20 additions & 1 deletion libuvc/libuvc.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -18,7 +18,10 @@
#ifndef LIBUVC_H
#define LIBUVC_H

#include <stddef.h>
#include <stdio.h>
#include <stdint.h>
#include <sys/ioctl.h>
#include <sys/time.h>

#ifdef __cplusplus
extern "C" {
Expand All @@ -28,12 +31,28 @@ struct uvc_ctx {
int fd;
int width;
int height;
struct timeval timestamp;
void *opaque;
};

struct video_cap {
uint8_t desc[32];
uint32_t version;
};

struct video_ctrl {
uint32_t cmd;
uint32_t val;
};

#define UVC_GET_CAP _IOWR('V', 0, struct video_cap)
#define UVC_SET_CTRL _IOWR('V', 1, struct video_ctrl)


struct uvc_ctx *uvc_open(const char *dev, int width, int height);
int uvc_print_info(struct uvc_ctx *c);
int uvc_read(struct uvc_ctx *c, void *buf, size_t len);
int uvc_ioctl(struct uvc_ctx *c, uint32_t cmd, void *buf, int len);
void uvc_close(struct uvc_ctx *c);


Expand Down
6 changes: 5 additions & 1 deletion libuvc/test_libuvc.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -29,12 +29,16 @@ int main(int argc, char **argv)
struct uvc_ctx *uvc = uvc_open("/dev/video0", 640, 480);
uvc_print_info(uvc);
struct file *fp = file_open("uvc.yuv", F_CREATE);
for (int i = 0; i < 20; ++i) {
for (int i = 0; i < 64; ++i) {
memset(frm, 0, flen);
size = uvc_read(uvc, frm, flen);
if (size == -1) {
continue;
}
file_write(fp, frm, size);
}
file_close(fp);
uvc_ioctl(uvc, UVC_GET_CAP, NULL, 0);
uvc_close(uvc);
return 0;
}

0 comments on commit f567e55

Please sign in to comment.