adding finished note reader converter

5 files changed, 681 insertions, 0 deletions

diff --git a/draw_grid.cpp b/draw_grid.cpp
new file mode 100644
index 0000000..de67681
--- /dev/null
+++ b/draw_grid.cpp
@@ -0,0 +1,104 @@
+#include <iostream>
+#include <fstream>
+#include <sstream>
+
+#include <opencv2/core/core.hpp>
+#include <opencv2/highgui/highgui.hpp>
+
+#include "draw_grid.hpp"
+
+using namespace cv;
+using namespace std;
+
+int main(int argc, char** argv) {
+	Mat firstGrid, secondGrid, thirdGrid, redPix1, redPix2;
+	Mat A4Grid(HEIGHT, WIDTH, CV_8UC3, Scalar(255, 255, 255));
+
+	int noteNum;
+	
+	fstream inputBits;
+
+	// get input
+	inputBits.open("noteBits1.txt");
+	inputBits >> noteNum;
+
+	int notes[BOXWIDTH][BOXHEIGHT];
+	string tmpStr;
+
+	for(int i = 0; i < noteNum; ++i) {
+		inputBits >> tmpStr;
+		for(int j = 0; j < BOXHEIGHT; ++j) {
+			notes[i][j] = int(tmpStr[j])-48;
+		}
+	}
+	inputBits.close();
+	
+	int tmpNote = noteNum;
+	inputBits.open("noteBits2.txt");
+	inputBits >> noteNum;
+
+	for(int i = tmpNote; i < noteNum+tmpNote; ++i) {
+		inputBits >> tmpStr;
+		for(int j = 0; j < BOXHEIGHT; ++j) {
+			notes[i][j] = int(tmpStr[j])-48;
+		}
+	}
+	inputBits.close();
+
+	initGrid(A4Grid, firstGrid, secondGrid, thirdGrid, redPix1, redPix2);
+	for(int y = 0; y < BOXHEIGHT; ++y) {
+		for(int x = 0; x < BOXWIDTH; ++x) {
+			if(x < tmpNote+noteNum) {
+			    if(!(notes[x][y] == 1)) {
+				    addBox(firstGrid, x, y);
+			    }
+			} else {
+				addBox(firstGrid, x, y);
+			}
+		}
+	}
+
+	imwrite("A4Grid.jpg", A4Grid);
+	return 0;
+}
+
+void initGrid(Mat &A4image, Mat &row1, Mat &row2, Mat &row3, Mat &redPix1, Mat &redPix2) {
+	row1 = A4image(Rect(BORDER, BORDER, WIDTH-2*BORDER, HEIGHT/GRIDNUM-2*BORDER));
+	//row2 = A4image(Rect(BORDER, HEIGHT/GRIDNUM+BORDER/2, WIDTH-2*BORDER, HEIGHT/GRIDNUM-2*BORDER));
+	//row3 = A4image(Rect(BORDER, 2*(HEIGHT/GRIDNUM)+BORDER/2, WIDTH-2*BORDER, HEIGHT/GRIDNUM-2*BORDER));
+
+	redPix1 = A4image(Rect(0, 0, DOTSIZE, DOTSIZE));
+	redPix2 = A4image(Rect(WIDTH-DOTSIZE, 0, DOTSIZE, DOTSIZE));
+	
+	colourRect(row1, Vec3b(0, 0, 0));
+	//colourRect(row2, Vec3b(0, 0, 0));
+	//colourRect(row3, Vec3b(0, 0, 0));
+	colourRect(redPix1, Vec3b(0, 0, 255));
+	colourRect(redPix2, Vec3b(0, 0, 255));
+}
+
+void addBox(Mat &rect, int xC, int yC) {
+	Mat rectCut = rect(Rect(BORDER, BORDER, rect.cols-2*BORDER, rect.rows-2*BORDER));
+
+	double xLd = (double(rectCut.cols)-BOXBORDER*(BOXWIDTH-1))/BOXWIDTH;
+	double yLd = (double(rectCut.rows)-BOXBORDER*(BOXHEIGHT-1))/BOXHEIGHT;
+	double xd = double(xC)*(xLd+BOXBORDER);
+	double yd = double(yC)*(yLd+BOXBORDER);
+
+	int xL = int(xLd);
+	int yL = int(yLd);
+	int x = int(xd);
+	int y = int(yd);
+	
+	Mat box = rectCut(Rect(x, y, xL, yL));
+	
+	colourRect(box, Vec3b(255, 255, 255));
+}
+
+void colourRect(Mat &inRect, Vec3b colour) {
+	for(int y = 0; y < inRect.rows; ++y) {
+		for(int x = 0; x < inRect.cols; ++x) {
+			inRect.at<Vec3b>(Point(x, y)) = colour;
+		}
+	}
+}
diff --git a/draw_grid.hpp b/draw_grid.hpp
new file mode 100644
index 0000000..46e64b1
--- /dev/null
+++ b/draw_grid.hpp
@@ -0,0 +1,15 @@
+// A4 Paper Dimensionsa
+#define HEIGHT 2481
+#define WIDTH 3510
+#define BOXHEIGHT 5
+#define BOXWIDTH 32
+#define BOXBORDER 10
+#define BORDER 20
+#define GRIDNUM 1
+#define DOTSIZE 40
+
+#include <opencv2/core/core.hpp>
+
+void initGrid(cv::Mat&, cv::Mat&, cv::Mat&, cv::Mat&, cv::Mat&, cv::Mat&);
+void addBox(cv::Mat&, int, int);
+void colourRect(cv::Mat &, cv::Vec3b colour);
diff --git a/get_notes.sh b/get_notes.sh
new file mode 100755
index 0000000..3df958f
--- /dev/null
+++ b/get_notes.sh
@@ -0,0 +1,8 @@
+convert -interlace none -density 150x150 -quality 50 "$1" "./score.jpg";
+g++ note_detection.cpp -o note_detection -fpermissive `pkg-config --libs opencv`;
+g++ draw_grid.cpp -o draw_grid -fpermissive `pkg-config --libs opencv`;
+./note_detection score.jpg 0;
+mv "./noteBits.txt" "./noteBits1.txt";
+./note_detection score.jpg 1;
+mv "./noteBits.txt" "./noteBits2.txt";
+./draw_grid
diff --git a/note_detection.cpp b/note_detection.cpp
new file mode 100644
index 0000000..b3ceaa3
--- /dev/null
+++ b/note_detection.cpp
@@ -0,0 +1,526 @@
+#include <iostream>
+#include <fstream>
+
+#include <opencv2/core/core.hpp>
+#include <opencv2/highgui/highgui.hpp>
+
+#include "note_detection.hpp"
+
+using namespace cv;
+using namespace std;
+
+int main(int argc, char** argv) {
+	// getting input for the file
+	char* imageName = argv[1];
+
+	int n;
+	
+	if(argc > 2) {
+	    char* input = argv[2];
+	    n = int(input[0])-48;
+	} else {
+		n = 0;
+	}
+
+	// initialising matrices
+	Mat image, imagebw;
+	Mat cut, cut2, cutbw, notes, notesbw;
+	
+	// Arrays that will contain the different components
+	int rowInt[HEIGHT];
+	int barLineLoc[THRESHOLD];
+	int staveLoc[STAVENUM];
+	int finalNotes[THRESHOLD*4];
+	int outPitch[THRESHOLD*4];
+	int noteType[THRESHOLD*4];
+	int notePitch[THRESHOLD*4];
+	int noteRests[THRESHOLD*4][2];
+	bool notesBool[THRESHOLD*4][NOTEBIT];
+
+	// Initialisation of the counting variables for the arrays
+	int barLineLocSize;
+	int staveLocSize;
+	int noteLocSize;
+	int noteNum;
+	int noteRestNum;
+
+	// Making filestreams for text output
+	ofstream noteStream;
+
+	// opening images into Mat
+	image = imread(imageName, 1);
+	imagebw = imread(imageName, 0);
+
+	// Array that will contain cols
+	int colInt[imagebw.cols];
+	int noteLoc[imagebw.cols];
+
+	if(!image.data) {
+		printf("No image data n");
+		return -1;
+	}
+
+	const int start = START+n*(685-393);
+	// cuts parts of the matrix and then copies them
+	Mat cut_off(image, Rect(0, start, image.cols, HEIGHT));
+	Mat cut_offbw(imagebw, Rect(0, start, image.cols, HEIGHT));
+	Mat note_cut(image, Rect(0, start, image.cols, NOTEHEIGHT));
+	Mat note_cutbw(imagebw, Rect(0, start, image.cols, NOTEHEIGHT));
+
+	// duplicates the images so that they can be changed without changing
+	// the original
+	cut_off.copyTo(cut);
+	cut.copyTo(cut2);
+	cut_offbw.copyTo(cutbw);
+	note_cut.copyTo(notes);
+	note_cutbw.copyTo(notesbw);
+
+	// finds the lengths of the vertical lines and horizontal pixels
+	findVertLines(cut_offbw, rowInt);
+	findHorizLines(cut_offbw, colInt);
+
+	// Finds the locations and size of the barLines
+	findPeaks(rowInt, HEIGHT, staveLoc, staveLocSize);
+	staveLoc[5] = staveLoc[4] - staveLoc[0] + staveLoc[1];
+	findPeaks(colInt, imagebw.cols, barLineLoc, barLineLocSize);
+
+	// finds the notes
+	findNotes(colInt, imagebw.cols, noteLoc, noteLocSize);
+
+	// extract the single notes
+	extractNotes(noteLoc, noteLocSize, finalNotes, noteNum);
+
+	// This section will find the pitch of the notes
+	findPitch(notesbw, staveLoc, finalNotes, noteNum, outPitch, noteType);
+
+	getNotePitch(staveLoc, outPitch, notePitch, noteNum);
+	
+	findRests(notePitch, finalNotes, noteType, noteRests, noteNum, noteRestNum);
+
+	for(int i = 0; i < noteRestNum; ++i) {
+		getKey(noteRests[i][1], 'c', notesBool[i]);
+	}
+	
+	// draws them to a file so that we can view and debug them
+	drawRowInt(cut, rowInt);
+	drawColInt(cut2, colInt);
+	drawNoteLoc(notes, finalNotes, noteNum);
+
+	// Writing all the outputs to files for logging
+	imwrite("cut_out.jpg", cut_offbw);
+	imwrite("cut_hist_horiz.jpg", cut);
+	imwrite("cut_hist_vert.jpg", cut2);
+	imwrite("note_detected.jpg", notes);
+	imwrite("pitch_detect.jpg", notesbw);
+
+	// Creating text files with the data for external access
+	noteStream.open("note.txt");
+	for(int i = 0; i < noteRestNum; ++i) {
+		noteStream << noteRests[i][0] << " " << noteRests[i][1] << endl;
+	}  
+	noteStream.close();
+
+	noteStream.open("noteBits.txt");
+	noteStream << noteRestNum << endl;
+	for(int i = 0; i < noteRestNum; ++i) {
+		for(int j = 0; j < NOTEBIT; ++j) {
+			noteStream << notesBool[i][j];
+		}
+		noteStream << endl;
+	}
+	noteStream.close();
+
+	return 0;
+}
+
+void findVertLines(Mat &image, int* rowInt) {
+	// goes through the image from left to right and counts number of
+	// black pixels
+	for(int y = 0; y < image.rows; ++y) {
+		int count = 0;
+		for(int x = 0; x < image.cols; ++x) {
+			if(image.at<uchar>(Point(x, y)) < 20) {
+				++count;
+			}
+		}
+		rowInt[y] = count;
+	}
+}
+
+void findHorizLines(Mat &image, int* colInt) {
+	// Same but from top to bottom
+	for(int x = 0; x < image.cols; ++x) {
+		int count = 0;
+		for(int y = 0; y < image.rows/2; ++y) {
+			if(image.at<uchar>(Point(x, y)) < 20) {
+				++count;
+			}
+		}
+		colInt[x] = count;
+	}
+}
+
+void drawRowInt(Mat &image, int* rowInt) {
+	// uses the array to draw the amount of pixels
+	for(int y = 0; y < image.rows; ++y) {
+		for(int x = 0; x < image.cols; ++x) {
+			if(x < rowInt[y]) {
+				image.at<Vec3b>(Point(x, y)) = Vec3b(0, 0, 255);
+			}
+		}
+	}
+}
+
+void drawColInt(Mat &image, int* colInt) {
+	for(int x = 0; x < image.cols; ++x) {
+		for(int y = 0; y < image.rows; ++y) {
+			if(y < colInt[x]) {
+				image.at<Vec3b>(Point(x, y)) = Vec3b(0, 0, 255);
+			}
+		}
+	}
+}
+
+void findPeaks(int* inputPeaks, int inLen, int* output, int &outLen) {
+	// calculates any peaks with a specific threshold
+	int max = inputPeaks[0];
+	int min, prev;
+	for(int i = 0; i < inLen; ++i) {
+		if(inputPeaks[i] > max) {
+			max = inputPeaks[i];
+		}
+	}
+	// sets the min according to a percentage of the max so that
+	// it scales correctly
+	min = max - max / THRESHOLD;
+	prev = 0;
+	outLen = 0;
+	for(int i = 0; i < inLen; ++i) {
+		// if there wasn't a peak before and the input is larger
+		if(inputPeaks[i] > min && i-1 > prev) {
+			output[outLen++] = i;
+			// updates the previous peak
+			prev = i + THRESHOLD / 2;
+		}
+	}
+}
+
+void findNotes(int* inputPeaks, int &inLen, int* output, int &outLen) {
+	// finds the notes between a certain threshold
+	outLen = 0;
+	for(int i = 0; i < inLen; ++i) {
+		if(inputPeaks[i] < TOPLIMIT && inputPeaks[i] > BOTLIMIT) {
+			output[outLen++] = i;
+		}
+	}
+}
+
+void drawNoteLoc(Mat &image, int* noteLoc, int &noteLocSize) {
+	// draws notes according to input
+	for(int y = 0; y < image.rows; ++y) {
+		for(int x = 0; x < image.cols; ++x) {
+			if(inside(noteLoc, noteLocSize, x)) {
+				image.at<Vec3b>(Point(x, y)) = Vec3b(255, 0, 0);
+			}
+		}
+	}
+}
+
+void extractNotes(int* input, int &inLen, int *tmpArr, int &outLen) {
+	int i = 0;
+	int output[inLen];
+	outLen = 0;
+	while(i < inLen) {
+	    int count = 0;
+		for(int j = input[i]; j < input[i]+THRESHOLD; ++j) {
+			if(inside(&input[i], THRESHOLD, j)) {
+				++count;
+			}
+		}
+		if(count > THRESHOLD-4) {
+			output[outLen++] = input[i];
+			i += THRESHOLD;
+		}
+		++i;
+	}
+	int tmpLen = 0;
+	bool changed = false;
+	for(int i = 0; i < outLen-1; ++i) {
+		if(output[i+1] - output[i] > THRESHOLD*2) {
+			if(changed) {
+			    tmpArr[tmpLen++] = output[i]-10;
+				changed = false;
+			} else {
+				tmpArr[tmpLen++] = output[i]-2;
+			}
+		} else {
+			changed = true;
+		}
+	}
+	if(changed) {
+	    tmpArr[tmpLen++] = output[outLen-1]-10;
+	} else {
+	    tmpArr[tmpLen++] = output[outLen-1]-2;
+	}
+	outLen = tmpLen;
+}
+
+bool inside(int* arr, int arrSize, int num) {
+	for(int x = 0; x < arrSize; ++x) {
+		if(arr[x] == num) {
+			return true;
+		}
+	}
+	return false;
+}
+
+void findPitch(Mat &inputLine, int* stave, int* inNote, int &inLen, int* outPitch, int* noteType) {
+	// Check where the first note is
+	// define pixels compared to the stave lines to detect
+
+	for(int i = 0; i < inLen; ++i) {
+		int totalCount[2] = {0, 0};
+		int count2 = 0;
+		bool tail = false;
+		int average = 0;
+		int avgCount = 0;
+		for(int j = 0; j < 25; ++j) {
+		    int count = 0;
+			for(int y = 0; y < inputLine.rows; ++y) {
+				if(inputLine.at<uchar>(Point(inNote[i]+j, y)) < 127 && !inside(stave, STAVENUM, y) && !inside(stave, STAVENUM, y-1) && !inside(stave, STAVENUM, y-2)) {
+					++count;
+					inputLine.at<uchar>(Point(inNote[i]+j, y)) = 127;
+				}
+			}
+			if(count > totalCount[0] && count < 15) {
+				totalCount[0] = count;
+				totalCount[1] = j;
+			} else if (count > 15) {
+				tail = true;
+			}
+			if(count < 15) {
+				count2 += count;
+			}
+		}
+		
+        for(int y = 0; y < inputLine.rows; ++y) {
+		    if(inputLine.at<uchar>(Point(inNote[i]+totalCount[1], y)) < 128 && !inside(stave, STAVENUM, y) && !inside(stave, STAVENUM, y-1) && !inside(stave, STAVENUM, y-2)) {
+				average += y;
+				++avgCount;
+			}
+		}
+		average /= avgCount;
+		outPitch[i] = average;
+        for(int y = 0; y < inputLine.rows; ++y) {
+			inputLine.at<uchar>(Point(inNote[i]+totalCount[1], y)) = 0;
+		}
+		if(count2 > 90 && !tail) {
+			noteType[i] = 2;
+		} else if(count2 > 90 && tail){
+			noteType[i] = 0;
+		} else {
+			noteType[i] = 1;
+		}
+	}
+}
+
+void getNotePitch(int *stave, int *loc, int *pitch, int &noteNum) {
+	for(int i = 0; i < noteNum; ++i) {
+		for(int j = 0; j < STAVENUM; ++j) {
+			int test[5] = {loc[i]-2, loc[i]-1, loc[i], loc[i]+1, loc[i]+2};
+			if(inside(test, 5, stave[j])) {
+				if(i > 0 && pitch[i-1] == 11-2*j) {
+				    pitch[i] = 31;
+				} else {
+					pitch[i] = 11-2*j;
+				}
+			} else {
+				if(inside(test, 5, stave[j]+(stave[j+1]-stave[j])/2)) {
+				    if(i > 0 && pitch[i-1] == 10-2*j) {
+					    pitch[i] = 31;
+				    } else {
+					    pitch[i] = 10-2*j;
+					}
+				}
+			}
+		}
+	}
+}
+
+void findRests(int *notePitch, int *noteLoc, int *noteType, int (*finalNotes)[2], int &noteNum, int &restNoteNum) {
+    restNoteNum = 0;
+	for(int i = 0; i < noteNum; ++i) {
+		if(noteType[i] == 0) {
+			finalNotes[restNoteNum][1] = notePitch[i];
+			finalNotes[restNoteNum++][0] = noteType[i];
+			if(i < noteNum-1 && (noteLoc[i+1] - noteLoc[i]) > NOTEDIFF) {
+			    finalNotes[restNoteNum][1] = 0;
+			    finalNotes[restNoteNum++][0] = -1;
+			}
+		} else if(noteType[i] == 1) {
+			finalNotes[restNoteNum][1] = notePitch[i];
+			finalNotes[restNoteNum++][0] = noteType[i];
+			finalNotes[restNoteNum][1] = notePitch[i];
+			finalNotes[restNoteNum++][0] = noteType[i];
+		    if(i < noteNum-1 && (noteLoc[i+1] - noteLoc[i]) > 2*NOTEDIFF) {
+			    finalNotes[restNoteNum][1] = 0;
+			    finalNotes[restNoteNum++][0] = -1;
+			}
+		} else if(noteType[i] == 2) {
+			finalNotes[restNoteNum][1] = notePitch[i];
+			finalNotes[restNoteNum++][0] = noteType[i];
+			finalNotes[restNoteNum][1] = notePitch[i];
+			finalNotes[restNoteNum++][0] = noteType[i];
+			finalNotes[restNoteNum][1] = notePitch[i];
+			finalNotes[restNoteNum++][0] = noteType[i];
+			finalNotes[restNoteNum][1] = notePitch[i];
+			finalNotes[restNoteNum++][0] = noteType[i];
+		    if(i < noteNum-1 && (noteLoc[i+1] - noteLoc[i]) > 4*NOTEDIFF) {
+			    finalNotes[restNoteNum][1] = 0;
+			    finalNotes[restNoteNum++][0] = -1;
+			}
+		} else {
+			cout << "Error" << endl;	
+		}
+	}
+}
+
+void getKey(int note, char key, bool *output) {
+	bool c_maj[11][5] ={{false, false, true, true, true}, 
+					{false, true, false, false, true},
+					{false, true, false, true, true},
+					{false, true, true, false, false},
+					{false, true, true, true, false},
+					{true, false, false, false, false},
+					{true, false, false, true, false},
+					{true, false, false, true, true},
+					{true, false, true, false, true},
+					{true, false, true, true, true},
+						{true, true, false, false, false}};
+	bool d_maj[11][5] ={{false, true, false, false, false},
+					{false, true, false, false, true}, 
+					{false, true, false, true, true},
+					{false, true, true, false, true},
+					{false, true, true, false, false},
+					{true, false, false, false, false},
+					{true, false, false, true, false},
+					{true, false, true, false, false},
+					{true, false, true, false, true},
+					{true, false, true, true, true},
+					{true, true, false, false, true}};
+	bool e_maj[11][5] ={{false, true, false, false, false},
+					{false, true, false, true, false},
+					{false, true, false, true, true},
+					{false, true, true, false, true},
+					{false, true, true, true, true},
+					{true, false, false, false, false},
+					{true, false, false, true, false},
+					{true, false, true, false, false},
+					{true, false, true, true, false},
+					{true, false, true, true, true},
+					{true, true, false, false, true}};
+	bool f_maj[11][5] ={{false, false, true, true, true},
+					{false, true, false, false, true},
+					{false, true, false, true, true},
+					{false, true, true, false, false},
+					{false, true, true, true, false},
+					{true, false, false, false, false},
+					{true, false, false, false, true},
+					{true, false, false, true, true},
+					{true, false, true, false, true},
+					{true, false, true, true, true},
+					{true, true, false, false, false}};
+	bool r_maj[11][5] ={{false, true, false, false, false},
+					{false, true, false, true, false},
+					{false, true, true, false, false},
+					{false, true, true, false, true},
+					{false, true, true, true, true},
+					{true, false, false, false, true},
+					{true, false, false, true, false},
+					{true, false, true, false, false},
+					{true, false, true, true, false},
+					{true, true, false, false, false},
+					{true, true, false, false, true}};
+	bool g_maj[11][5] ={{false, false, true, true, true},
+					{false, true, false, false, true},
+					{false, true, false, true, true},
+					{false, true, true, false, true},
+					{false, true, true, true, false}, 
+					{true, false, false, false, false},
+					{true, false, false, true, false},
+					{true, false, false, true, true},
+					{true, false, true, false, true},
+					{true, false, true, true, true},
+					{true, true, false, false, true}};
+	bool a_maj[11][5] ={{false, true, false, false, false},
+					{false, true, false, false, true},
+					{false, true, false, true, true},
+					{false, true, true, false, true},
+					{false, true, true, true, true},
+					{true, false, false, false, false}, 
+					{true, false, false, true, false},
+					{true, false, true, false, false},
+					{true, false, true, false, true},
+					{true, false, true, true, true},
+					{true, true, false, false, true}};
+	bool b_maj[11][5] ={{false, true, false, false, false},
+					{false, true, false, true, false},
+					{false, true, false, true, true},
+					{false, true, true, false, true},
+					{false, true, true, true, true},
+					{true, false, false, false, true},
+					{true, false, false, true, false}, 
+					{true, false, true, false, false},
+					{true, false, true, true, false},
+					{true, false, true, true, true},
+					{true, true, false, false, true}};
+	if (note == 0) {
+		bool rest[5] = {false, false, false, false, false};
+		for(int i = 0; i < 5; ++i) {
+			output[i] = rest[i];
+		}
+	}
+	else if (note == 31) {
+		bool repeat[5] = {true, true, true, true, true};
+		for(int i = 0; i < 5; ++i) {
+			output[i] = repeat[i];
+		}
+	}
+	else
+	{
+		bool key_arr[11][5];
+		for(int i = 0; i < 11; ++i) {
+			for(int j = 0; j < 5; ++j) {
+		        switch (key) {
+			        case 'c':
+				        key_arr[i][j] = c_maj[i][j];
+				        break;
+			        case 'd':
+				        key_arr[i][j] = d_maj[i][j];
+				        break;
+			        case 'e':
+				        key_arr[i][j] = e_maj[i][j];
+				        break;
+			        case 'f':
+				        key_arr[i][j] = f_maj[i][j];
+		         		break;
+	         		case 'r':
+				        key_arr[i][j] = r_maj[i][j];
+        				break;
+        			case 'g':
+				        key_arr[i][j] = g_maj[i][j];
+        				break;
+	        		case 'a':
+				        key_arr[i][j] = a_maj[i][j];
+	        			break;
+        			case 'b':
+				        key_arr[i][j] = b_maj[i][j];
+	        			break;
+				}
+			}
+		}
+		for(int i = 0; i < 5; ++i) {
+			output[i] = key_arr[note-1][i];
+		}
+	}
+}
diff --git a/note_detection.hpp b/note_detection.hpp
new file mode 100644
index 0000000..0b745b4
--- /dev/null
+++ b/note_detection.hpp
@@ -0,0 +1,28 @@
+#include <opencv2/core/core.hpp>
+
+// constant definitions
+#define HEIGHT 220
+#define NOTEHEIGHT 90
+#define START 393     // FIRST LINE: 393; SECOND LINE: 685
+#define THRESHOLD 10
+#define LINEAPPROXIMATION 3
+#define STAVENUM 6
+#define TOPLIMIT 25
+#define BOTLIMIT 14
+#define NOTEBIT 5
+#define NOTEDIFF 120
+
+// all the functions used
+void drawRowInt(cv::Mat&, int*);
+void findHorizLines(cv::Mat&, int*);
+void drawColInt(cv::Mat&, int*);
+void findVertLines(cv::Mat&, int*);
+void findPeaks(int*, int, int*, int&);
+void findNotes(int*, int&, int*, int&);
+void drawNoteLoc(cv::Mat&, int*, int&);
+void extractNotes(int*, int&, int*, int&);
+bool inside(int*, int, int);
+void findPitch(cv::Mat&, int*, int*, int&, int*, int*);
+void getNotePitch(int*, int*, int*, int&);
+void findRests(int*, int*, int*, int(*)[2], int&, int&);
+void getKey(int, char, bool*);