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POreading a barcode with a webcam
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copied!<p>Hey,<br> I'm trying to read a EAN-13 barcode from my webcam.<br> I already wrote a class to do that work.<br> I'm taking a picture from my webcam, trimming it to show ONLY the barcode,<br> and reading the barcode with the code tables from wikipedia.<br> For some reason, the barcode gets trimmed, but the output is always "0-1-1-1-1-1-1-1-1-1-1-1-1".<br> I wonder if i did any stupid mistake or misunderstood something? </p> <p>I do not want to use ANY third-party programs!</p> <p>this is my code for now:</p> <pre><code> public class BarcodeDecoder { static string[] ligerade = new string[] { "0100111", "0110011", "0011011", "0100001", "0011101", "0000101", "0010001", "0001001", "0010111" }; static string[] rechtsgerade = new string[ligerade.Length]; static string[] liungerade = new string[ligerade.Length]; static string[] GeradeUG = new string[] { "UUUUUU", "UUGUGG", "UUGGUG", "UUGGGU", "UGUUGG", "UGGUUG", "UGGGUU", "UGUGUG", "UGUGGU", "UGGUGU" }; static int[] links; static int[] rechts; static string result; public static string Decode(Bitmap b) { result = ""; Bitmap bb = CutOutOf(b, b.Height / 2); bb = trimBitmap(bb); int[] lgs = GetNumberOutOf(bb); int[][] rr = trimArray(lgs); links = rr[0]; rechts = rr[1]; FillArrays(); BearbeiteLinks(); BearbeiteRechts(); return result; } static void BearbeiteLinks() { string GU = ""; string[] zahlen = new string[6]; zahlen[0] = OutOfArray(links, 0, 7); zahlen[1] = OutOfArray(links, 7, 7); zahlen[2] = OutOfArray(links, 14, 7); zahlen[3] = OutOfArray(links, 21, 7); zahlen[4] = OutOfArray(links, 28, 7); zahlen[5] = OutOfArray(links, 35, 7); foreach (string pq in zahlen) { bool gerade = ligerade.ToList().IndexOf(pq) > -1; if (gerade) { result += ligerade.ToList().IndexOf(pq).ToString(); GU += "G"; } else { result += liungerade.ToList().IndexOf(pq).ToString(); GU += "U"; } } result = GeradeUG.ToList().IndexOf(GU).ToString() + result; } static void BearbeiteRechts() { string[] zahlen = new string[6]; zahlen[0] = OutOfArray(rechts, 0, 7); zahlen[1] = OutOfArray(rechts, 7, 7); zahlen[2] = OutOfArray(rechts, 14, 7); zahlen[3] = OutOfArray(rechts, 21, 7); zahlen[4] = OutOfArray(rechts, 28, 7); zahlen[5] = OutOfArray(rechts, 35, 7); foreach (string pq in zahlen) { result += rechtsgerade.ToList().IndexOf(pq).ToString(); } } static string OutOfArray(int[] ar, int startindex, int length) { int[] gar = new int[length]; Array.Copy(ar, startindex, gar, 0, length); StringBuilder bilder = new StringBuilder(); for (int i = 0; i < gar.Length; i++) { bilder.Append(gar[i].ToString()); } return bilder.ToString(); } static Bitmap trimBitmap(Bitmap b) { bool alreadyBlack = false; int firstblack = 0; for (int i = 0; i < b.Width; i++) { Color gp = b.GetPixel(i, 0); if ((gp.R + gp.G + gp.B) / 3 < 128) { if (!alreadyBlack) { alreadyBlack = true; firstblack = i; } } } bool alreadyblack = false; int lastblack = 0; for (int i = b.Width -1; i > 0; i--) { Color gpp = b.GetPixel(i, 0); if ((gpp.R + gpp.G + gpp.B) / 3 < 128) { if (!alreadyblack) { alreadyblack = true; lastblack = i; } } } Bitmap result = new Bitmap(lastblack - firstblack, 1); for (int i = firstblack; i < lastblack; i++) { Color c = b.GetPixel(i, 0); result.SetPixel(i - firstblack, 0, c); } result.Save("C:\\result.bmp", System.Drawing.Imaging.ImageFormat.Bmp); return result; } static int[][] trimArray(int[] ar) { int[][] res = new int[2][]; int[] resl = new int[6 * 7]; int[] resr = new int[6 * 7]; Array.Copy(ar, 2, resl, 0, 6 * 7); Array.Copy(ar, 2 + 6 * 7 + 5, resr, 0, 6 * 7); res[0] = resl; res[1] = resr; return res; } static void FillArrays() { for (int i = 0; i < ligerade.Length; i++) { rechtsgerade[i] = string.Concat(ligerade[i].Reverse()); } for (int x = 0; x < liungerade.Length; x++) { liungerade[x] = Invert(rechtsgerade[x]); } } static string Invert(string xx) { string xs = ""; for (int y = 0; y < xx.Length; y++) { int fd = int.Parse(xx[y].ToString()); if (fd == 0) fd = 1; else fd = 0; xs += fd.ToString(); } return xs; } static Bitmap CutOutOf(Bitmap b, int y) { Bitmap res = new Bitmap(b.Width, 1); for (int i = 0; i < b.Width; i++) { Color c = b.GetPixel(i, y); res.SetPixel(i, 0, c); } return res; } static int[] GetNumberOutOf(Bitmap bb) { List<int> intlst = new List<int>(); float f = (float)bb.Width / 95.0f; float wd = f / 2.0f; for (float i = wd; i < bb.Width; i+=f) { Color c = bb.GetPixel((int)Math.Round(i,0), 0); intlst.Add(GetOutOfColor(c)); } return intlst.ToArray(); } static int GetOutOfColor(Color c) { if (c.A + c.B + c.R > 128 * 3) { return 0; } return 1; } } </code></pre> <p>Sorry for german names in the code!</p>

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