csharp/qrcode/QRCodeWriter.cs

   1 /*\r
   2 * Copyright 2008 ZXing authors\r
   3 *\r
   4 * Licensed under the Apache License, Version 2.0 (the "License");\r
   5 * you may not use this file except in compliance with the License.\r
   6 * You may obtain a copy of the License at\r
   7 *\r
   8 *      http://www.apache.org/licenses/LICENSE-2.0\r
   9 *\r
  10 * Unless required by applicable law or agreed to in writing, software\r
  11 * distributed under the License is distributed on an "AS IS" BASIS,\r
  12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
  13 * See the License for the specific language governing permissions and\r
  14 * limitations under the License.\r
  15 */\r
  16 using System;\r
  17 using BarcodeFormat = com.google.zxing.BarcodeFormat;\r
  18 using EncodeHintType = com.google.zxing.EncodeHintType;\r
  19 using Writer = com.google.zxing.Writer;\r
  20 using WriterException = com.google.zxing.WriterException;\r
  21 using ByteMatrix = com.google.zxing.common.ByteMatrix;\r
  22 using Encoder = com.google.zxing.qrcode.encoder.Encoder;\r
  23 using QRCode = com.google.zxing.qrcode.encoder.QRCode;\r
  24 using ErrorCorrectionLevel = com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;\r
  25 namespace com.google.zxing.qrcode\r
  26 {\r
  27         \r
  28         /// <summary> This object renders a QR Code as a ByteMatrix 2D array of greyscale values.\r
  29         /// \r
  30         /// </summary>\r
  31         /// <author>  dswitkin@google.com (Daniel Switkin)\r
  32         /// </author>\r
  33         /// <author>www.Redivivus.in (suraj.supekar@redivivus.in) - Ported from ZXING Java Source \r
  34         /// </author>\r
  35         public sealed class QRCodeWriter : Writer\r
  36         {\r
  37                 \r
  38                 private const int QUIET_ZONE_SIZE = 4;\r
  39                 \r
  40                 public ByteMatrix encode(System.String contents, BarcodeFormat format, int width, int height)\r
  41                 {\r
  42                         \r
  43                         return encode(contents, format, width, height, null);\r
  44                 }\r
  45                 \r
  46                 public ByteMatrix encode(System.String contents, BarcodeFormat format, int width, int height, System.Collections.Hashtable hints)\r
  47                 {\r
  48                         \r
  49                         if (contents == null || contents.Length == 0)\r
  50                         {\r
  51                                 throw new System.ArgumentException("Found empty contents");\r
  52                         }\r
  53                         \r
  54                         if (format != BarcodeFormat.QR_CODE)\r
  55                         {\r
  56                                 throw new System.ArgumentException("Can only encode QR_CODE, but got " + format);\r
  57                         }\r
  58                         \r
  59                         if (width < 0 || height < 0)\r
  60                         {\r
  61                                 throw new System.ArgumentException("Requested dimensions are too small: " + width + 'x' + height);\r
  62                         }\r
  63                         \r
  64                         ErrorCorrectionLevel errorCorrectionLevel = ErrorCorrectionLevel.L;\r
  65                         if (hints != null)\r
  66                         {\r
  67                                 ErrorCorrectionLevel requestedECLevel = (ErrorCorrectionLevel) hints[EncodeHintType.ERROR_CORRECTION];\r
  68                                 if (requestedECLevel != null)\r
  69                                 {\r
  70                                         errorCorrectionLevel = requestedECLevel;\r
  71                                 }\r
  72                         }\r
  73                         \r
  74                         QRCode code = new QRCode();\r
  75                         Encoder.encode(contents, errorCorrectionLevel, hints, code);\r
  76                         return renderResult(code, width, height);\r
  77                 }\r
  78                 \r
  79                 // Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses\r
  80                 // 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap).\r
  81                 private static ByteMatrix renderResult(QRCode code, int width, int height)\r
  82                 {\r
  83                         ByteMatrix input = code.Matrix;\r
  84                         int inputWidth = input.Width;\r
  85                         int inputHeight = input.Height;\r
  86                         int qrWidth = inputWidth + (QUIET_ZONE_SIZE << 1);\r
  87                         int qrHeight = inputHeight + (QUIET_ZONE_SIZE << 1);\r
  88                         int outputWidth = System.Math.Max(width, qrWidth);\r
  89                         int outputHeight = System.Math.Max(height, qrHeight);\r
  90                         \r
  91                         int multiple = System.Math.Min(outputWidth / qrWidth, outputHeight / qrHeight);\r
  92                         // Padding includes both the quiet zone and the extra white pixels to accommodate the requested\r
  93                         // dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone.\r
  94                         // If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will\r
  95                         // handle all the padding from 100x100 (the actual QR) up to 200x160.\r
  96                         int leftPadding = (outputWidth - (inputWidth * multiple)) / 2;\r
  97                         int topPadding = (outputHeight - (inputHeight * multiple)) / 2;\r
  98                         \r
  99                         ByteMatrix output = new ByteMatrix(outputWidth, outputHeight);\r
 100                         sbyte[][] outputArray = output.Array;\r
 101                         \r
 102                         // We could be tricky and use the first row in each set of multiple as the temporary storage,\r
 103                         // instead of allocating this separate array.\r
 104                         sbyte[] row = new sbyte[outputWidth];\r
 105                         \r
 106                         // 1. Write the white lines at the top\r
 107                         for (int y = 0; y < topPadding; y++)\r
 108                         {\r
 109                                 setRowColor(outputArray[y], (sbyte) SupportClass.Identity(255));\r
 110                         }\r
 111                         \r
 112                         // 2. Expand the QR image to the multiple\r
 113                         sbyte[][] inputArray = input.Array;\r
 114                         for (int y = 0; y < inputHeight; y++)\r
 115                         {\r
 116                                 // a. Write the white pixels at the left of each row\r
 117                                 for (int x = 0; x < leftPadding; x++)\r
 118                                 {\r
 119                                         row[x] = (sbyte) SupportClass.Identity(255);\r
 120                                 }\r
 121                                 \r
 122                                 // b. Write the contents of this row of the barcode\r
 123                                 int offset = leftPadding;\r
 124                                 for (int x = 0; x < inputWidth; x++)\r
 125                                 {\r
 126                     // Redivivus.in Java to c# Porting update - Type cased sbyte\r
 127                     // 30/01/2010 \r
 128                                         // sbyte value_Renamed = (inputArray[y][x] == 1)?0:(sbyte) SupportClass.Identity(255);\r
 129                     sbyte value_Renamed = (sbyte)((inputArray[y][x] == 1) ? 0 : SupportClass.Identity(255));\r
 130                                         for (int z = 0; z < multiple; z++)\r
 131                                         {\r
 132                                                 row[offset + z] = value_Renamed;\r
 133                                         }\r
 134                                         offset += multiple;\r
 135                                 }\r
 136                                 \r
 137                                 // c. Write the white pixels at the right of each row\r
 138                                 offset = leftPadding + (inputWidth * multiple);\r
 139                                 for (int x = offset; x < outputWidth; x++)\r
 140                                 {\r
 141                                         row[x] = (sbyte) SupportClass.Identity(255);\r
 142                                 }\r
 143                                 \r
 144                                 // d. Write the completed row multiple times\r
 145                                 offset = topPadding + (y * multiple);\r
 146                                 for (int z = 0; z < multiple; z++)\r
 147                                 {\r
 148                                         Array.Copy(row, 0, outputArray[offset + z], 0, outputWidth);\r
 149                                 }\r
 150                         }\r
 151                         \r
 152                         // 3. Write the white lines at the bottom\r
 153                         int offset2 = topPadding + (inputHeight * multiple);\r
 154                         for (int y = offset2; y < outputHeight; y++)\r
 155                         {\r
 156                                 setRowColor(outputArray[y], (sbyte) SupportClass.Identity(255));\r
 157                         }\r
 158                         \r
 159                         return output;\r
 160                 }\r
 161                 \r
 162                 private static void  setRowColor(sbyte[] row, sbyte value_Renamed)\r
 163                 {\r
 164                         for (int x = 0; x < row.Length; x++)\r
 165                         {\r
 166                                 row[x] = value_Renamed;\r
 167                         }\r
 168                 }\r
 169         }\r
 170 }