// Capture support for WinRT
// Copyright (c) Microsoft Open Technologies, Inc.
// All rights reserved.
//
// (3 - clause BSD License)
//
// Redistribution and use in source and binary forms, with or without modification, are permitted provided that
// the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the
// following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
// following disclaimer in the documentation and/or other materials provided with the distribution.
// 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or
// promote products derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE ARE DISCLAIMED.IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY
// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES(INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT(INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
#include "precomp.hpp"
#include "cap_winrt_capture.hpp"
#include "cap_winrt_bridge.hpp"
#include "cap_winrt_video.hpp"
#include <opencv2\videoio\cap_winrt.hpp>
using namespace Windows::Foundation;
using namespace Windows::Media::Capture;
using namespace Windows::Media::MediaProperties;
using namespace Windows::Devices::Enumeration;
using namespace Platform;
using namespace Windows::UI::Xaml::Media::Imaging;
using namespace Microsoft::WRL;
using namespace ::std;
namespace cv {
/******************************* exported API functions **************************************/
template <typename ...Args>
void winrt_startMessageLoop(std::function<void(Args...)>&& callback, Args... args)
{
auto asyncTask = ::concurrency::create_async([=](::concurrency::progress_reporter<int> reporter)
{
VideoioBridge::getInstance().setReporter(reporter);
// frame reading loop
callback(args...);
});
asyncTask->Progress = ref new AsyncActionProgressHandler<int>([=](IAsyncActionWithProgress<int>^ act, int progress)
{
int action = progress;
// these actions will be processed on the UI thread asynchronously
switch (action)
{
case OPEN_CAMERA:
VideoioBridge::getInstance().openCamera();
break;
case CLOSE_CAMERA:
Video::getInstance().closeGrabber();
break;
case UPDATE_IMAGE_ELEMENT:
VideoioBridge::getInstance().updateFrameContainer();
break;
}
});
}
template <typename ...Args>
void winrt_startMessageLoop(void callback(Args...), Args... args)
{
winrt_startMessageLoop(std::function<void(Args...)>(callback), args...);
}
void winrt_onVisibilityChanged(bool visible)
{
if (visible)
{
VideoioBridge& bridge = VideoioBridge::getInstance();
// only start the grabber if the camera was opened in OpenCV
if (bridge.backInputPtr != nullptr)
{
if (Video::getInstance().isStarted()) return;
int device = bridge.getDeviceIndex();
int width = bridge.getWidth();
int height = bridge.getHeight();
Video::getInstance().initGrabber(device, width, height);
}
} else
{
//grabberStarted = false;
Video::getInstance().closeGrabber();
}
}
void winrt_imshow()
{
VideoioBridge::getInstance().imshow();
}
void winrt_setFrameContainer(::Windows::UI::Xaml::Controls::Image^ image)
{
VideoioBridge::getInstance().cvImage = image;
}
/********************************* VideoCapture_WinRT class ****************************/
VideoCapture_WinRT::VideoCapture_WinRT(int device) : started(false)
{
VideoioBridge::getInstance().setDeviceIndex(device);
}
bool VideoCapture_WinRT::isOpened() const
{
return true; // started;
}
// grab a frame:
// this will NOT block per spec
// should be called on the image processing thread, not the UI thread
bool VideoCapture_WinRT::grabFrame()
{
// if device is not started we must return true so retrieveFrame() is called to start device
// nb. we cannot start the device here because we do not know the size of the input Mat
if (!started) return true;
if (VideoioBridge::getInstance().bIsFrameNew)
{
return true;
}
// nb. if blocking is to be added:
// unique_lock<mutex> lock(VideoioBridge::getInstance().frameReadyMutex);
// VideoioBridge::getInstance().frameReadyEvent.wait(lock);
return false;
}
// should be called on the image processing thread after grabFrame
// see VideoCapture::read
bool VideoCapture_WinRT::retrieveFrame(int channel, cv::OutputArray outArray)
{
if (!started) {
int width, height;
width = outArray.size().width;
height = outArray.size().height;
if (width == 0) width = 640;
if (height == 0) height = 480;
VideoioBridge::getInstance().setWidth(width);
VideoioBridge::getInstance().setHeight(height);
// nb. Mats will be alloc'd on UI thread
// request device init on UI thread - this does not block, and is async
VideoioBridge::getInstance().requestForUIthreadAsync(OPEN_CAMERA);
started = true;
return false;
}
if (!started) return false;
return VideoioBridge::getInstance().bIsFrameNew;
}
bool VideoCapture_WinRT::setProperty(int property_id, double value)
{
switch (property_id)
{
case CAP_PROP_FRAME_WIDTH:
size.width = (int)value;
break;
case CAP_PROP_FRAME_HEIGHT:
size.height = (int)value;
break;
default:
return false;
}
return true;
}
}