--- /dev/null
+/*\r
+* Copyright 2007 ZXing authors\r
+*\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
+using System;\r
+namespace com.google.zxing.qrcode.decoder\r
+{\r
+ \r
+ /// <summary> <p>Encapsulates a QR Code's format information, including the data mask used and\r
+ /// error correction level.</p>\r
+ /// \r
+ /// </summary>\r
+ /// <author> Sean Owen\r
+ /// </author>\r
+ /// <author>www.Redivivus.in (suraj.supekar@redivivus.in) - Ported from ZXING Java Source \r
+ /// </author>\r
+ /// <seealso cref="DataMask">\r
+ /// </seealso>\r
+ /// <seealso cref="ErrorCorrectionLevel">\r
+ /// </seealso>\r
+ sealed class FormatInformation\r
+ {\r
+ internal ErrorCorrectionLevel ErrorCorrectionLevel\r
+ {\r
+ get\r
+ {\r
+ return errorCorrectionLevel;\r
+ }\r
+ \r
+ }\r
+ internal sbyte DataMask\r
+ {\r
+ get\r
+ {\r
+ return dataMask;\r
+ }\r
+ \r
+ }\r
+ \r
+ private const int FORMAT_INFO_MASK_QR = 0x5412;\r
+ \r
+ /// <summary> See ISO 18004:2006, Annex C, Table C.1</summary>\r
+ //UPGRADE_NOTE: Final was removed from the declaration of 'FORMAT_INFO_DECODE_LOOKUP'. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1003'"\r
+ private static readonly int[][] FORMAT_INFO_DECODE_LOOKUP = new int[][]{new int[]{0x5412, 0x00}, new int[]{0x5125, 0x01}, new int[]{0x5E7C, 0x02}, new int[]{0x5B4B, 0x03}, new int[]{0x45F9, 0x04}, new int[]{0x40CE, 0x05}, new int[]{0x4F97, 0x06}, new int[]{0x4AA0, 0x07}, new int[]{0x77C4, 0x08}, new int[]{0x72F3, 0x09}, new int[]{0x7DAA, 0x0A}, new int[]{0x789D, 0x0B}, new int[]{0x662F, 0x0C}, new int[]{0x6318, 0x0D}, new int[]{0x6C41, 0x0E}, new int[]{0x6976, 0x0F}, new int[]{0x1689, 0x10}, new int[]{0x13BE, 0x11}, new int[]{0x1CE7, 0x12}, new int[]{0x19D0, 0x13}, new int[]{0x0762, 0x14}, new int[]{0x0255, 0x15}, new int[]{0x0D0C, 0x16}, new int[]{0x083B, 0x17}, new int[]{0x355F, 0x18}, new int[]{0x3068, 0x19}, new int[]{0x3F31, 0x1A}, new int[]{0x3A06, 0x1B}, new int[]{0x24B4, 0x1C}, new int[]{0x2183, 0x1D}, new int[]{0x2EDA, 0x1E}, new int[]{0x2BED, 0x1F}};\r
+ \r
+ /// <summary> Offset i holds the number of 1 bits in the binary representation of i</summary>\r
+ //UPGRADE_NOTE: Final was removed from the declaration of 'BITS_SET_IN_HALF_BYTE'. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1003'"\r
+ private static readonly int[] BITS_SET_IN_HALF_BYTE = new int[]{0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4};\r
+ \r
+ //UPGRADE_NOTE: Final was removed from the declaration of 'errorCorrectionLevel '. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1003'"\r
+ private ErrorCorrectionLevel errorCorrectionLevel;\r
+ //UPGRADE_NOTE: Final was removed from the declaration of 'dataMask '. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1003'"\r
+ private sbyte dataMask;\r
+ \r
+ private FormatInformation(int formatInfo)\r
+ {\r
+ // Bits 3,4\r
+ errorCorrectionLevel = ErrorCorrectionLevel.forBits((formatInfo >> 3) & 0x03);\r
+ // Bottom 3 bits\r
+ dataMask = (sbyte) (formatInfo & 0x07);\r
+ }\r
+ \r
+ internal static int numBitsDiffering(int a, int b)\r
+ {\r
+ a ^= b; // a now has a 1 bit exactly where its bit differs with b's\r
+ // Count bits set quickly with a series of lookups:\r
+ return BITS_SET_IN_HALF_BYTE[a & 0x0F] + BITS_SET_IN_HALF_BYTE[(SupportClass.URShift(a, 4) & 0x0F)] + BITS_SET_IN_HALF_BYTE[(SupportClass.URShift(a, 8) & 0x0F)] + BITS_SET_IN_HALF_BYTE[(SupportClass.URShift(a, 12) & 0x0F)] + BITS_SET_IN_HALF_BYTE[(SupportClass.URShift(a, 16) & 0x0F)] + BITS_SET_IN_HALF_BYTE[(SupportClass.URShift(a, 20) & 0x0F)] + BITS_SET_IN_HALF_BYTE[(SupportClass.URShift(a, 24) & 0x0F)] + BITS_SET_IN_HALF_BYTE[(SupportClass.URShift(a, 28) & 0x0F)];\r
+ }\r
+ \r
+ /// <param name="maskedFormatInfo">format info indicator, with mask still applied\r
+ /// </param>\r
+ /// <returns> information about the format it specifies, or <code>null</code>\r
+ /// if doesn't seem to match any known pattern\r
+ /// </returns>\r
+ internal static FormatInformation decodeFormatInformation(int maskedFormatInfo)\r
+ {\r
+ FormatInformation formatInfo = doDecodeFormatInformation(maskedFormatInfo);\r
+ if (formatInfo != null)\r
+ {\r
+ return formatInfo;\r
+ }\r
+ // Should return null, but, some QR codes apparently\r
+ // do not mask this info. Try again by actually masking the pattern\r
+ // first\r
+ return doDecodeFormatInformation(maskedFormatInfo ^ FORMAT_INFO_MASK_QR);\r
+ }\r
+ \r
+ private static FormatInformation doDecodeFormatInformation(int maskedFormatInfo)\r
+ {\r
+ // Find the int in FORMAT_INFO_DECODE_LOOKUP with fewest bits differing\r
+ int bestDifference = System.Int32.MaxValue;\r
+ int bestFormatInfo = 0;\r
+ for (int i = 0; i < FORMAT_INFO_DECODE_LOOKUP.Length; i++)\r
+ {\r
+ int[] decodeInfo = FORMAT_INFO_DECODE_LOOKUP[i];\r
+ int targetInfo = decodeInfo[0];\r
+ if (targetInfo == maskedFormatInfo)\r
+ {\r
+ // Found an exact match\r
+ return new FormatInformation(decodeInfo[1]);\r
+ }\r
+ int bitsDifference = numBitsDiffering(maskedFormatInfo, targetInfo);\r
+ if (bitsDifference < bestDifference)\r
+ {\r
+ bestFormatInfo = decodeInfo[1];\r
+ bestDifference = bitsDifference;\r
+ }\r
+ }\r
+ // Hamming distance of the 32 masked codes is 7, by construction, so <= 3 bits\r
+ // differing means we found a match\r
+ if (bestDifference <= 3)\r
+ {\r
+ return new FormatInformation(bestFormatInfo);\r
+ }\r
+ return null;\r
+ }\r
+ \r
+ public override int GetHashCode()\r
+ {\r
+ return (errorCorrectionLevel.ordinal() << 3) | (int) dataMask;\r
+ }\r
+ \r
+ public override bool Equals(System.Object o)\r
+ {\r
+ if (!(o is FormatInformation))\r
+ {\r
+ return false;\r
+ }\r
+ FormatInformation other = (FormatInformation) o;\r
+ return this.errorCorrectionLevel == other.errorCorrectionLevel && this.dataMask == other.dataMask;\r
+ }\r
+ }\r
+}
\ No newline at end of file
projects / zxing.git / blobdiff