void MjpegCamera::print_control_range(__u32 id) {
struct v4l2_queryctrl queryctrl;
query_control(id, queryctrl);
fprintf(stderr, "%s: min=%d max=%d step=%d",
queryctrl.name, (int) queryctrl.minimum,
(int) queryctrl.maximum,
(int) queryctrl.step
);
}
void MjpegCamera::gain(int gain) {
struct v4l2_queryctrl queryctrl;
query_control(V4L2_CID_BRIGHTNESS, queryctrl);
if (gain < 0) { gain = 0; }
if (gain > 100) { gain = 100; }
int new_brightness = gain * (queryctrl.maximum - queryctrl.minimum) / 100
+ queryctrl.minimum;
try_set_control(V4L2_CID_BRIGHTNESS, new_brightness);
}
void MjpegCamera::focus(int focus_value) {
struct v4l2_queryctrl queryctrl;
query_control(V4L2_CID_FOCUS_ABSOLUTE, queryctrl);
if (focus_value < 0) { focus_value = 0; }
if (focus_value > 100) { focus_value = 100; }
int new_focus = focus_value * (queryctrl.maximum - queryctrl.minimum) / 100
+ queryctrl.minimum;
try_set_control(V4L2_CID_FOCUS_AUTO, 0);
try_set_control(V4L2_CID_FOCUS_ABSOLUTE, new_focus);
}
void MjpegCamera::try_set_control(__u32 id, __s32 value) {
struct v4l2_queryctrl queryctrl;
struct v4l2_control control;
query_control(id, queryctrl);
if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) {
return; /* control not supported */
} else {
memset(&control, 0, sizeof(control));
control.id = id;
control.value = value;
xioctl(VIDIOC_S_CTRL, &control);
}
}
bool AVConfig::Init()
{
int video_device = NULL;
const char *device_name;
struct stat st;
//check if there're essential settings
if(!getRoot()->exists("audio"))
getRoot()->add("audio", Setting::TypeGroup);
if(!getRoot()->exists("video"))
getRoot()->add("video", Setting::TypeGroup);
//open video device
if(!getVideoSettings()->exists("device"))
getVideoSettings()->add("device", Setting::TypeString) = "/dev/video0";
device_name = (*getVideoSettings())["device"];
if(-1 == stat(device_name, &st))
{
log_message(1, "AVConfig: Cannot identify '%s': %d, %s.", device_name, errno, strerror (errno));
return false;
}
if(!S_ISCHR(st.st_mode))
{
log_message(1, "AVConfig: %s is no device.", device_name);
return false;
}
video_device = open(device_name, O_RDWR | O_NONBLOCK, 0);
if(-1 == video_device)
{
log_message(1, "AVConfig: Cannot open '%s': %d, %s.", device_name, errno, strerror (errno));
exit (EXIT_FAILURE);
}
//determine video device capabilities
v4l2_capability cap;
if(-1 == xioctl(video_device, VIDIOC_QUERYCAP, &cap))
{
if (EINVAL == errno)
{
log_message(1, "AVConfig: %s is no V4L2 device.", device_name);
exit(1);
}
else log_message(1, "AVConfig: VIDIOC_QUERYCAP: %d, %s.", errno, strerror(errno));
}
if(!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE))
{
log_message(1, "AVConfig: %s is no video capture device.", device_name);
exit(1);
}
if(cap.capabilities & V4L2_CAP_READWRITE)
log_message(0, "AVConfig: %s supports read i/o.", device_name);
if(cap.capabilities & V4L2_CAP_STREAMING)
log_message(0, "AVConfig: %s supports streaming i/o.", device_name);
//enumerate inputs
vector<v4l2_input> input_list;
v4l2_input input;
int current_input;
CLEAR(input);
input.index = 0;
while(-1 != xioctl(video_device, VIDIOC_ENUMINPUT, &input))
{
input_list.push_back(input);
log_message(0, "AVConfig: Input [%d -- %s] is found.", input.index, input.name);
input.index++;
}
if(-1 == xioctl(video_device, VIDIOC_G_INPUT, ¤t_input))
{
log_errno("AVConfig: VIDIOC_G_INPUT");
exit(1);
}
log_message(0, "AVConfig: Currently selected input is: %d -- %s.", current_input, input_list[current_input].name);
//enumerate standards if applied
vector<v4l2_standard> standard_list;
v4l2_standard standard;
v4l2_std_id current_standard;
CLEAR(standard);
standard.index = 0;
if(-1 != xioctl(video_device, VIDIOC_G_STD, ¤t_standard))
{
while(0 == xioctl(video_device, VIDIOC_ENUMSTD, &standard))
{
if(standard.id & input_list[current_input].std)
{
standard_list.push_back(standard);
log_message(0, "AVConfig: Standard %s is supported by current input.", standard.name);
log_message(0, "AVConfig: The framerate defined by this standard is: %d", standard.frameperiod.denominator/standard.frameperiod.numerator);
if(standard.id == current_standard)
log_message(0, "AVConfig: Standard %s is currently selected on input.", standard.name);
}
standard.index++;
}
if(errno != EINVAL || standard.index == 0)
{
log_errno("AVConfig: VIDIOC_ENUMSTD");
return false;
}
}
//enumerate controls
vector<v4l2_queryctrl> queryctrl_list;
vector<v4l2_control> control_list;
map<unsigned long, vector<v4l2_querymenu> > querymenu_list;
v4l2_queryctrl queryctrl;
v4l2_control control;
CLEAR(queryctrl);
CLEAR(control);
log_message(0, "AVConfig: Quering standard controls");
queryctrl.id = V4L2_CID_BASE;
while(queryctrl.id < V4L2_CID_LASTP1)
{
queryctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
control.id = queryctrl.id;
int res = query_control(video_device, &queryctrl, &control,
queryctrl_list, control_list, querymenu_list);
if(-1 == res)
{
log_errno("AVConfig: unable to query device control");
return false;
}
else if(0 == res) break;
}
log_message(0, "AVConfig: Quering driver specific controls");
queryctrl.id = V4L2_CID_PRIVATE_BASE;
while(true)
{
queryctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
control.id = queryctrl.id;
int res = query_control(video_device, &queryctrl, &control,
queryctrl_list, control_list, querymenu_list);
if(-1 == res)
{
log_errno("AVConfig: unable to query device control");
return false;
}
else if(0 == res) break;
}
//close the device
close(video_device);
//construct inputs setting
Setting *video = getVideoSettings();
try{ video->remove("input"); } catch(...){}
video->add("input", Setting::TypeInt) = current_input;
try{ video->remove("inputs"); } catch(...){}
Setting &inputs = video->add("inputs", Setting::TypeGroup);
for(int i = 0; i < input_list.size(); i++)
inputs.add(fix_str(input_list[i].name), Setting::TypeInt) = i;
//construct standarts setting
try{ video->remove("standard"); } catch(...){}
try{ video->remove("standards"); } catch(...){}
if(!standard_list.empty())
{
video->add("standard", Setting::TypeInt64) = (long long)current_standard;
Setting &standards = video->add("standards", Setting::TypeGroup);
for(int i = 0; i < standard_list.size(); i++)
standards.add(fix_str(standard_list[i].name), Setting::TypeInt64) = (long long)standard_list[i].id;
}
//construct controls setting
try{ video->remove("controls"); } catch(...){}
Setting &controls = video->add("controls", Setting::TypeGroup);
for(int i = 0; i < queryctrl_list.size(); i++)
{
Setting &control = controls.add(fix_str(queryctrl_list[i].name), Setting::TypeGroup);
control.add("id", Setting::TypeInt) = (int)queryctrl_list[i].id;
control.add("value", Setting::TypeInt) = (int)control_list[i].value;
control.add("default_value", Setting::TypeInt) = (int)queryctrl_list[i].default_value;
if(queryctrl_list[i].type == V4L2_CTRL_TYPE_MENU)
{
vector<v4l2_querymenu> items = querymenu_list[(int)queryctrl_list[i].id];
for(int j = 0; j < items.size(); j++)
control.add(fix_str(items[j].name), Setting::TypeInt64) = (long long)items[j].index;
}
else
{
control.add("minimum", Setting::TypeInt) = (int)queryctrl_list[i].minimum;
control.add("maximum", Setting::TypeInt) = (int)queryctrl_list[i].maximum;
control.add("step", Setting::TypeInt) = (int)queryctrl_list[i].step;
}
}
return true;
}
