--- /dev/null
+/*\r
+* Licensed under the Apache License, Version 2.0 (the "License");\r
+* you may not use this file except in compliance with the License.\r
+* You may obtain a copy of the License at\r
+*\r
+* http://www.apache.org/licenses/LICENSE-2.0\r
+*\r
+* Unless required by applicable law or agreed to in writing, software\r
+* distributed under the License is distributed on an "AS IS" BASIS,\r
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
+* See the License for the specific language governing permissions and\r
+* limitations under the License.\r
+*/\r
+namespace com.google.zxing.oned\r
+{\r
+ using System;\r
+ using System.Text;\r
+ using com.google.zxing.common;\r
+\r
+\r
+ public sealed class Code39Reader : AbstractOneDReader \r
+ { \r
+ private static String ALPHABET_STRING = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-. *$/+%";\r
+ private static char[] ALPHABET = ALPHABET_STRING.ToCharArray();\r
+\r
+ /**\r
+ * These represent the encodings of characters, as patterns of wide and narrow bars.\r
+ * The 9 least-significant bits of each int correspond to the pattern of wide and narrow,\r
+ * with 1s representing "wide" and 0s representing narrow.\r
+ */\r
+ private static int[] CHARACTER_ENCODINGS = {\r
+ 0x034, 0x121, 0x061, 0x160, 0x031, 0x130, 0x070, 0x025, 0x124, 0x064, // 0-9\r
+ 0x109, 0x049, 0x148, 0x019, 0x118, 0x058, 0x00D, 0x10C, 0x04C, 0x01C, // A-J\r
+ 0x103, 0x043, 0x142, 0x013, 0x112, 0x052, 0x007, 0x106, 0x046, 0x016, // K-T\r
+ 0x181, 0x0C1, 0x1C0, 0x091, 0x190, 0x0D0, 0x085, 0x184, 0x0C4, 0x094, // U-*\r
+ 0x0A8, 0x0A2, 0x08A, 0x02A // $-%\r
+ };\r
+\r
+ private static int ASTERISK_ENCODING = CHARACTER_ENCODINGS[39];\r
+\r
+ private bool usingCheckDigit;\r
+ private bool extendedMode;\r
+\r
+ /**\r
+ * Creates a reader that assumes all encoded data is data, and does not treat the \r
+ * character as a check digit. It will not decoded "extended Code 39" sequences.\r
+ */\r
+ public Code39Reader() {\r
+ usingCheckDigit = false;\r
+ extendedMode = false;\r
+ }\r
+\r
+ /**\r
+ * Creates a reader that can be configured to check the last character as a check digit.\r
+ * It will not decoded "extended Code 39" sequences.\r
+ *\r
+ * @param usingCheckDigit if true, treat the last data character as a check digit, not\r
+ * data, and verify that the checksum passes.\r
+ */\r
+ public Code39Reader(bool usingCheckDigit) {\r
+ this.usingCheckDigit = usingCheckDigit;\r
+ this.extendedMode = false;\r
+ }\r
+\r
+ /**\r
+ * Creates a reader that can be configured to check the last character as a check digit,\r
+ * or optionally attempt to decode "extended Code 39" sequences that are used to encode\r
+ * the full ASCII character set.\r
+ *\r
+ * @param usingCheckDigit if true, treat the last data character as a check digit, not\r
+ * data, and verify that the checksum passes.\r
+ * @param extendedMode if true, will attempt to decode extended Code 39 sequences in the\r
+ * text.\r
+ */\r
+ public Code39Reader(bool usingCheckDigit, bool extendedMode) {\r
+ this.usingCheckDigit = usingCheckDigit;\r
+ this.extendedMode = extendedMode;\r
+ }\r
+\r
+ public override Result decodeRow(int rowNumber, BitArray row, System.Collections.Hashtable hints) {\r
+\r
+ int[] start = findAsteriskPattern(row);\r
+ int nextStart = start[1];\r
+ int end = row.getSize();\r
+\r
+ // Read off white space\r
+ while (nextStart < end && !row.get(nextStart)) {\r
+ nextStart++;\r
+ }\r
+\r
+ StringBuilder result = new StringBuilder();\r
+ int[] counters = new int[9];\r
+ char decodedChar;\r
+ int lastStart;\r
+ do {\r
+ recordPattern(row, nextStart, counters);\r
+ int pattern = toNarrowWidePattern(counters);\r
+ decodedChar = patternToChar(pattern);\r
+ result.Append(decodedChar);\r
+ lastStart = nextStart;\r
+ for (int i = 0; i < counters.Length; i++) {\r
+ nextStart += counters[i];\r
+ }\r
+ // Read off white space\r
+ while (nextStart < end && !row.get(nextStart)) {\r
+ nextStart++;\r
+ }\r
+ } while (decodedChar != '*');\r
+\r
+ result.Remove(result.Length - 1, 1); // remove asterisk\r
+\r
+ // Look for whitespace after pattern:\r
+ int lastPatternSize = 0;\r
+ for (int i = 0; i < counters.Length; i++) {\r
+ lastPatternSize += counters[i];\r
+ }\r
+ int whiteSpaceAfterEnd = nextStart - lastStart - lastPatternSize;\r
+ // If 50% of last pattern size, following last pattern, is not whitespace, fail\r
+ // (but if it's whitespace to the very end of the image, that's OK)\r
+ if (nextStart != end && whiteSpaceAfterEnd / 2 < lastPatternSize) {\r
+ throw new ReaderException();\r
+ }\r
+\r
+ if (usingCheckDigit) {\r
+ int max = result.Length - 1;\r
+ int total = 0;\r
+ for (int i = 0; i < max; i++) {\r
+ total += ALPHABET_STRING.IndexOf(result[i]);\r
+ }\r
+ if (total % 43 != ALPHABET_STRING.IndexOf(result[max]))\r
+ {\r
+ throw new ReaderException();\r
+ }\r
+ result.Remove(max,1);\r
+ }\r
+\r
+ String resultString = result.ToString();\r
+ if (extendedMode) {\r
+ resultString = decodeExtended(resultString);\r
+ }\r
+\r
+ if (resultString.Length == 0) {\r
+ // Almost surely a false positive\r
+ throw new ReaderException();\r
+ }\r
+\r
+ float left = (float) (start[1] + start[0]) / 2.0f;\r
+ float right = (float) (nextStart + lastStart) / 2.0f;\r
+ return new Result(\r
+ resultString,\r
+ null,\r
+ new ResultPoint[]{\r
+ new GenericResultPoint(left, (float) rowNumber),\r
+ new GenericResultPoint(right, (float) rowNumber)},\r
+ BarcodeFormat.CODE_39);\r
+\r
+ }\r
+\r
+ private static int[] findAsteriskPattern(BitArray row) {\r
+ int width = row.getSize();\r
+ int rowOffset = 0;\r
+ while (rowOffset < width) {\r
+ if (row.get(rowOffset)) {\r
+ break;\r
+ }\r
+ rowOffset++;\r
+ }\r
+\r
+ int counterPosition = 0;\r
+ int[] counters = new int[9];\r
+ int patternStart = rowOffset;\r
+ bool isWhite = false;\r
+ int patternLength = counters.Length;\r
+\r
+ for (int i = rowOffset; i < width; i++) {\r
+ bool pixel = row.get(i);\r
+ if ((!pixel && isWhite) || (pixel && !isWhite)) {\r
+ counters[counterPosition]++;\r
+ } else {\r
+ if (counterPosition == patternLength - 1) {\r
+ try {\r
+ if (toNarrowWidePattern(counters) == ASTERISK_ENCODING) {\r
+ // Look for whitespace before start pattern, >= 50% of width of start pattern\r
+ if (row.isRange(Math.Max(0, patternStart - (i - patternStart) / 2), patternStart, false)) {\r
+ return new int[]{patternStart, i};\r
+ }\r
+ }\r
+ } catch (ReaderException re) {\r
+ // no match, continue\r
+ }\r
+ patternStart += counters[0] + counters[1];\r
+ for (int y = 2; y < patternLength; y++) {\r
+ counters[y - 2] = counters[y];\r
+ }\r
+ counters[patternLength - 2] = 0;\r
+ counters[patternLength - 1] = 0;\r
+ counterPosition--;\r
+ } else {\r
+ counterPosition++;\r
+ }\r
+ counters[counterPosition] = 1;\r
+ isWhite = !isWhite;\r
+ }\r
+ }\r
+ throw new ReaderException();\r
+ }\r
+\r
+ private static int toNarrowWidePattern(int[] counters) {\r
+ int numCounters = counters.Length;\r
+ int maxNarrowCounter = 0;\r
+ int wideCounters;\r
+ do {\r
+ int minCounter = int.MaxValue;\r
+ for (int i = 0; i < numCounters; i++) {\r
+ int counter = counters[i];\r
+ if (counter < minCounter && counter > maxNarrowCounter) {\r
+ minCounter = counter;\r
+ }\r
+ }\r
+ maxNarrowCounter = minCounter;\r
+ wideCounters = 0;\r
+ int totalWideCountersWidth = 0;\r
+ int pattern = 0;\r
+ for (int i = 0; i < numCounters; i++) {\r
+ int counter = counters[i];\r
+ if (counters[i] > maxNarrowCounter) {\r
+ pattern |= 1 << (numCounters - 1 - i);\r
+ wideCounters++;\r
+ totalWideCountersWidth += counter;\r
+ }\r
+ }\r
+ if (wideCounters == 3) {\r
+ // Found 3 wide counters, but are they close enough in width?\r
+ // We can perform a cheap, conservative check to see if any individual\r
+ // counter is more than 1.5 times the average:\r
+ for (int i = 0; i < numCounters && wideCounters > 0; i++) {\r
+ int counter = counters[i];\r
+ if (counters[i] > maxNarrowCounter) {\r
+ wideCounters--;\r
+ // totalWideCountersWidth = 3 * average, so this checks if counter >= 3/2 * average\r
+ if ((counter << 1) >= totalWideCountersWidth) {\r
+ throw new ReaderException();\r
+ }\r
+ }\r
+ }\r
+ return pattern;\r
+ }\r
+ } while (wideCounters > 3);\r
+ throw new ReaderException();\r
+ }\r
+\r
+ private static char patternToChar(int pattern) {\r
+ for (int i = 0; i < CHARACTER_ENCODINGS.Length; i++) {\r
+ if (CHARACTER_ENCODINGS[i] == pattern) {\r
+ return ALPHABET[i];\r
+ }\r
+ }\r
+ throw new ReaderException();\r
+ }\r
+\r
+ private static String decodeExtended(String encoded) {\r
+ int Length = encoded.Length;\r
+ StringBuilder decoded = new StringBuilder(Length);\r
+ for (int i = 0; i < Length; i++) {\r
+ char c = encoded[i];\r
+ if (c == '+' || c == '$' || c == '%' || c == '/') {\r
+ char next = encoded[i + 1];\r
+ char decodedChar = '\0';\r
+ switch (c) {\r
+ case '+':\r
+ // +A to +Z map to a to z\r
+ if (next >= 'A' && next <= 'Z') {\r
+ decodedChar = (char) (next + 32);\r
+ } else {\r
+ throw new ReaderException();\r
+ }\r
+ break;\r
+ case '$':\r
+ // $A to $Z map to control codes SH to SB\r
+ if (next >= 'A' && next <= 'Z') {\r
+ decodedChar = (char) (next - 64);\r
+ } else {\r
+ throw new ReaderException();\r
+ }\r
+ break;\r
+ case '%':\r
+ // %A to %E map to control codes ESC to US\r
+ if (next >= 'A' && next <= 'E') {\r
+ decodedChar = (char) (next - 38);\r
+ } else if (next >= 'F' && next <= 'W') {\r
+ decodedChar = (char) (next - 11);\r
+ } else {\r
+ throw new ReaderException();\r
+ }\r
+ break;\r
+ case '/':\r
+ // /A to /O map to ! to , and /Z maps to :\r
+ if (next >= 'A' && next <= 'O') {\r
+ decodedChar = (char) (next - 32);\r
+ } else if (next == 'Z') {\r
+ decodedChar = ':';\r
+ } else {\r
+ throw new ReaderException();\r
+ }\r
+ break;\r
+ }\r
+ decoded.Append(decodedChar);\r
+ // bump up i again since we read two characters\r
+ i++;\r
+ } else {\r
+ decoded.Append(c);\r
+ }\r
+ }\r
+ return decoded.ToString();\r
+ }\r
+\r
+ \r
+ }\r
+}
\ No newline at end of file
projects / zxing.git / blobdiff