public static OpenFieldReaderResult FindBoxes(int[] imgData, int row, int col, OpenFieldReaderOptions options)
{
// Debug image.
int[,] debugImg = null;
if (options.GenerateDebugImage)
{
debugImg = new int[row, col];
for (int y = 0; y < row; y++)
{
for (int x = 0; x < col; x++)
{
debugImg[y, x] = 0;
}
}
}
// We are seaching for pattern!
// We look for junctions.
// This will help us make a decision.
// Junction types: T, L, +.
// Junctions allow us to find boxes contours.
int width = options.JunctionWidth;
int height = options.JunctionHeight;
// Cache per line speed up the creation of various cache.
Dictionary <int, List <Junction> > cacheListJunctionPerLine = new Dictionary <int, List <Junction> >();
List <Junction> listJunction = new List <Junction>();
// If there is too much junction near each other, maybe it's just a black spot.
// We must ignore it to prevent wasting CPU and spend too much time.
int maxProximity = 10;
for (int y = 1; y < row - 1; y++)
{
List <Junction> listJunctionX = null;
int proximityCounter = 0;
for (int x = 1; x < col - 1; x++)
{
Junction?junction = GetJunction(imgData, row, col, height, width, y, x);
if (junction != null)
{
if (listJunctionX == null)
{
listJunctionX = new List <Junction>();
}
listJunctionX.Add(junction.Value);
proximityCounter++;
}
else
{
if (listJunctionX != null)
{
if (proximityCounter < maxProximity)
{
if (!cacheListJunctionPerLine.ContainsKey(y))
{
cacheListJunctionPerLine.Add(y, new List <Junction>());
}
cacheListJunctionPerLine[y].AddRange(listJunctionX);
listJunction.AddRange(listJunctionX);
listJunctionX.Clear();
}
else
{
listJunctionX.Clear();
}
}
proximityCounter = 0;
}
}
if (proximityCounter < maxProximity && listJunctionX != null)
{
if (!cacheListJunctionPerLine.ContainsKey(y))
{
cacheListJunctionPerLine.Add(y, new List <Junction>());
}
cacheListJunctionPerLine[y].AddRange(listJunctionX);
listJunction.AddRange(listJunctionX);
}
}
if (options.Verbose)
{
Console.WriteLine("Junction.count: " + listJunction.Count);
}
if (listJunction.Count >= options.MaxJunctions)
{
// Something wrong happen. Too much junction for now.
// If we continue, we would spend too much time processing the image.
// Let's suppose we don't know.
return(new OpenFieldReaderResult
{
// Too many junctions. The image seem too complex. You may want to increase MaxJunctions
ReturnCode = 10
});
}
// Let's check the list of points.
// Search near same line.
// TODO: should be parameters. (Can speed up process if you know what you are looking for.)
int minX = 15; // Min estimated cell width (should not be less than 15.)
int maxX = 80; // Max estimated cell width (should not be greater than 85. Most of the time, it can be reduced to 50 or 60.)
int variationY = 3; // Variation of y to find next cell. (should be really small for faster result)
// Prepare cache to speedup searching algo.
Dictionary <int, Junction[]> cacheNearJunction = new Dictionary <int, Junction[]>();
Dictionary <int, Junction[]> cachePossibleNextJunctionRight = new Dictionary <int, Junction[]>();
Dictionary <int, Junction[]> cachePossibleNextJunctionLeft = new Dictionary <int, Junction[]>();
foreach (var junction in listJunction)
{
var listJunctionNearJunction = new List <Junction>();
for (int deltaY = -variationY; deltaY <= variationY; deltaY++)
{
if (cacheListJunctionPerLine.ContainsKey(junction.Y - deltaY))
{
listJunctionNearJunction.AddRange(cacheListJunctionPerLine[junction.Y - deltaY]);
}
}
var list = listJunctionNearJunction
.Where(m =>
Math.Abs(m.X - junction.X) <= maxX
)
.ToArray();
var id = junction.X | junction.Y << 16;
cacheNearJunction.Add(id, list);
var possibleNextJunction = list
.Where(m =>
Math.Abs(m.X - junction.X) >= minX
)
.ToList();
cachePossibleNextJunctionLeft.Add(id, possibleNextJunction.Where(m => m.X < junction.X).ToArray());
cachePossibleNextJunctionRight.Add(id, possibleNextJunction.Where(m => m.X > junction.X).ToArray());
}
int numSol = 0;
List <Line> possibleSol = new List <Line>();
// We use a dictionary here because we need a fast way to remove entry.
// We reduce computation and we also merge solutions.
var elements = listJunction.OrderBy(m => m.Y).ToDictionary(m => m.X | m.Y << 16, m => m);
int skipSol = 0;
while (elements.Any())
{
var start = elements.First().Value;
elements.Remove(start.X | start.Y << 16);
Dictionary <int, List <int> > usedJunctionsForGapX = new Dictionary <int, List <int> >();
List <Line> listSolutions = new List <Line>();
var junctionsForGap = cacheNearJunction[start.X | start.Y << 16];
for (int iGap = 0; iGap < junctionsForGap.Length; iGap++)
{
var gap = junctionsForGap[iGap];
// Useless because it's already done with: cacheNearJunction.
/*
* var gapY = Math.Abs(gap.Y - start.Y);
* if (gapY > 2)
* {
* continue;
* }*/
var gapX = Math.Abs(gap.X - start.X);
if (gapX <= minX || gapX > maxX)
{
continue;
}
// We will reduce list of solution by checking if the solution is already found.
//if (listSolutions.Any(m => Math.Abs(m.GapX - gapX) < 2 && m.Junctions.Contains(start)))
if (usedJunctionsForGapX.ContainsKey(gap.X | gap.Y << 16) &&
usedJunctionsForGapX[gap.X | gap.Y << 16].Any(m => Math.Abs(m - gapX) < 10))
{
skipSol++;
continue;
}
List <Junction> curSolution = new List <Junction>();
curSolution.Add(start);
int numElementsRight = FindElementsOnDirection(cachePossibleNextJunctionRight, start, gap, gapX, curSolution);
int numElementsLeft = FindElementsOnDirection(cachePossibleNextJunctionLeft, start, gap, -gapX, curSolution);
int numElements = numElementsLeft + numElementsRight;
if (numElements >= options.MinNumElements)
{
if (numSol == options.MaxSolutions)
{
// Something wrong happen. Too much solution for now.
// If we continue, we would spend too much time processing the image.
// Let's suppose we don't know.
return(new OpenFieldReaderResult
{
// Too much solution. You may want to increase MaxSolutions.
ReturnCode = 30
});
}
numSol++;
listSolutions.Add(new Line
{
GapX = gapX,
Junctions = curSolution.ToArray()
});
foreach (var item in curSolution)
{
List <int> listGapX;
if (!usedJunctionsForGapX.ContainsKey(item.X | item.Y << 16))
{
listGapX = new List <int>();
usedJunctionsForGapX.Add(item.X | item.Y << 16, listGapX);
}
else
{
listGapX = usedJunctionsForGapX[item.X | item.Y << 16];
}
listGapX.Add(gapX);
}
}
}
Line bestSol = listSolutions.OrderByDescending(m => m.Junctions.Count()).FirstOrDefault();
if (bestSol != null)
{
// Too slow. (faster if we skip removal)
// But, we have more solutions.
foreach (var item in bestSol.Junctions)
{
elements.Remove(item.X | item.Y << 16);
}
possibleSol.Add(bestSol);
}
}
if (options.Verbose)
{
Console.WriteLine("Skip solutions counter: " + skipSol);
Console.WriteLine(numSol + " : Solution found");
Console.WriteLine(possibleSol.Count + " : Best solution found");
}
// Let's merge near junctions. (vertical line)
// We assign a group id for each clusters.
Dictionary <int, int> junctionToGroupId = new Dictionary <int, int>();
int nextGroupId = 1;
foreach (var curSolution in possibleSol)
{
if (curSolution.Junctions.First().GroupId == 0)
{
for (int i = 0; i < curSolution.Junctions.Length; i++)
{
ref var j = ref curSolution.Junctions[i];
j.GapX = curSolution.GapX;
}
// Not assigned yet.
// Find near junction.
int groupId = 0;
foreach (var item in curSolution.Junctions)
{
var alreadyClassified = cacheNearJunction[item.X | item.Y << 16]
.Where(m =>
// Doesn't work with struct.
//m.GroupId != 0 &&
Math.Abs(m.X - item.X) <= 5 &&
Math.Abs(m.Y - item.Y) <= 3
// Doesn't work with struct.
//Math.Abs(m.GapX - item.GapX) <= 2
).Where(m => junctionToGroupId.ContainsKey(m.X | m.Y << 16));
if (alreadyClassified.Any())
{
Junction junction = alreadyClassified.First();
groupId = junctionToGroupId[junction.X | junction.Y << 16];
//groupId = alreadyClassified.First().GroupId;
break;
}
}
if (groupId == 0)
{
// Not found.
// Create a new group.
nextGroupId++;
groupId = nextGroupId;
}
for (int i = 0; i < curSolution.Junctions.Length; i++)
{
ref var j = ref curSolution.Junctions[i];
j.GroupId = groupId;
int id = j.X | j.Y << 16;
if (!junctionToGroupId.ContainsKey(id))
{
junctionToGroupId.Add(id, groupId);
}
}
}
private static void Run(OpenFieldReaderOptions options)
{
try
{
using (var image = Image.Load(options.InputFile))
{
try
{
int row = image.Height;
int col = image.Width;
int[] imgData = new int[row * col];
for (int y = 0; y < row; y++)
{
for (int x = 0; x < col; x++)
{
var pixel = image[x, y];
var val = pixel.R | pixel.G | pixel.B;
imgData[y + x * row] = val > 122 ? 0 : 255;
}
}
var result = OpenFieldReader.FindBoxes(imgData, row, col, options);
if (result.ReturnCode != 0)
{
if (options.Verbose)
{
Console.WriteLine("Exit with code: " + result.ReturnCode);
}
Environment.Exit(result.ReturnCode);
}
if (options.OutputFile == "std")
{
// Show result on the console.
Console.WriteLine("Boxes: " + result.Boxes.Count);
Console.WriteLine();
int iBox = 1;
foreach (var box in result.Boxes)
{
Console.WriteLine("Box #" + iBox);
foreach (var element in box)
{
Console.WriteLine(" Element: " +
element.TopLeft + "; " +
element.TopRight + "; " +
element.BottomRight + "; " +
element.BottomLeft);
}
iBox++;
}
Console.WriteLine("Press any key to continue...");
Console.ReadLine();
}
else
{
// Write result to output file.
var outputPath = options.OutputFile;
var json = JsonSerializer.ToJsonString(result);
File.WriteAllText(outputPath, json);
}
}
catch (Exception ex)
{
Console.WriteLine("File: " + options.InputFile);
Console.WriteLine("Something wrong happen: " + ex.Message + Environment.NewLine + ex.StackTrace);
Environment.Exit(3);
}
}
}
catch (Exception ex)
{
Console.WriteLine("File: " + options.InputFile);
Console.WriteLine("Something wrong happen: " + ex.Message + Environment.NewLine + ex.StackTrace);
Environment.Exit(2);
}
}