#include "ComponentBackgroundSubtractionGray.h"

#define THISCLASS ComponentBackgroundSubtractionGray



#include <highgui.h>

#include "DisplayEditor.h"



THISCLASS::ComponentBackgroundSubtractionGray(SwisTrackCore *stc):

		Component(stc, wxT("BackgroundSubtractionGray")),

		mBackgroundImage(0), mBackgroundImageMean(cvScalarAll(0)),

		mCorrectMean(true), mMode(sMode_AbsDiff),

		mDisplayOutput(wxT("Output"), wxT("After background subtraction")) {



	// Data structure relations

	mCategory = &(mCore->mCategoryPreprocessingGray);

	AddDataStructureRead(&(mCore->mDataStructureImageGray));

	AddDataStructureWrite(&(mCore->mDataStructureImageGray));

	AddDisplay(&mDisplayOutput);



	// Read the XML configuration file

	Initialize();

}



THISCLASS::~ComponentBackgroundSubtractionGray() {

}



void THISCLASS::OnStart() {

	// Load the background image

	wxString filename_string = GetConfigurationString(wxT("BackgroundImage"), wxT(""));

	wxFileName filename = mCore->GetProjectFileName(filename_string);

	if (filename.IsOk()) {

		mBackgroundImage = cvLoadImage(filename.GetFullPath().mb_str(wxConvFile), CV_LOAD_IMAGE_ANYDEPTH | CV_LOAD_IMAGE_ANYCOLOR);

	}

	if (! mBackgroundImage) {

		AddError(wxT("Cannot open background image."));

		return;

	}



	// Check the background image

	// We explicitely do not convert image to grayscale automatically, as this is likely to be a configuration error of the user (e.g. wrong background selected). In addition, the user can easily convert a file to grayscale.

	if (mBackgroundImage->nChannels != 1) {

		AddError(wxT("Background image is not grayscale."));

		return;

	}



	// Read the reloadable parameters

	OnReloadConfiguration();

}



void THISCLASS::OnReloadConfiguration() {

	// Whether to correct the mean or not

	mCorrectMean = GetConfigurationBool(wxT("CorrectMean"), true);



	// Mode

	wxString modestr = GetConfigurationString(wxT("Mode"), wxT("AbsDiff"));

	if (modestr == wxT("SubImageBackground")) {

		mMode = sMode_SubImageBackground;

	} else if (modestr == wxT("SubBackgroundImage")) {

		mMode = sMode_SubBackgroundImage;

	} else {

		mMode = sMode_AbsDiff;

	}



	// We always calculate the background average, so we can select if we use the moving threshold during the segmentation

	if (mCorrectMean) {

		mBackgroundImageMean = cvAvg(mBackgroundImage);

	} else {

		mBackgroundImageMean = cvScalar(0);

	}

}



void THISCLASS::OnStep() {

	// Get and check input image

	IplImage *inputimage = mCore->mDataStructureImageGray.mImage;

	if (! inputimage) {

		AddError(wxT("No input image."));

		return;

	}

	if (inputimage->nChannels != 1) {

		AddError(wxT("The input image is not a grayscale image."));

		return;

	}



	// Check the background image

	if (! mBackgroundImage) {

		AddError(wxT("No background image loaded."));

		return;

	}

	if ((cvGetSize(inputimage).height != cvGetSize(mBackgroundImage).height) || (cvGetSize(inputimage).width != cvGetSize(mBackgroundImage).width)) {

		AddError(wxT("Input and background images don't have the same size."));

		return;

	}



	try {

		// Correct the inputimage with the difference in image mean

		if (mCorrectMean) {

			cvAddS(inputimage, cvScalar(mBackgroundImageMean.val[0] - cvAvg(inputimage).val[0]), inputimage);

		}



		// Background subtraction

		if (mMode == sMode_SubImageBackground) {

			cvSub(inputimage, mBackgroundImage, inputimage);

		} else if (mMode == sMode_SubBackgroundImage) {

			cvSub(mBackgroundImage, inputimage, inputimage);

		} else {

			cvAbsDiff(inputimage, mBackgroundImage, inputimage);

		}

	} catch (...) {

		AddError(wxT("Background subtraction failed."));

	}



	// Set the display

	DisplayEditor de(&mDisplayOutput);

	if (de.IsActive()) {

		de.SetMainImage(inputimage);

	}

}



void THISCLASS::OnStepCleanup() {

}



void THISCLASS::OnStop() {

	if (mBackgroundImage) {

		cvReleaseImage(&mBackgroundImage);

	}

}