private UInt32[] CalculateHuffmanCode() { UInt32[] array = new UInt32[17]; Byte[] array2 = this.codeLengthArray; for (Int32 i = 0; i < (Int32)array2.Length; i++) { Int32 num = (Int32)array2[i]; array[num] += 1u; } array[0] = 0u; UInt32[] array3 = new UInt32[17]; UInt32 num2 = 0u; for (Int32 j = 1; j <= 16; j++) { num2 = num2 + array[j - 1] << 1; array3[j] = num2; } UInt32[] array4 = new UInt32[288]; for (Int32 k = 0; k < (Int32)this.codeLengthArray.Length; k++) { Int32 num3 = (Int32)this.codeLengthArray[k]; if (num3 > 0) { array4[k] = FastEncoderStatics.BitReverse(array3[num3], num3); array3[num3] += 1u; } } return(array4); }
// Calculate the huffman code for each character based on the code length for each character. // This algorithm is described in standard RFC 1951 private uint[] CalculateHuffmanCode() { var bitLengthCount = new uint[17]; foreach (int codeLength in codeLengthArray) { bitLengthCount[codeLength]++; } bitLengthCount[0] = 0; // clear count for length 0 var nextCode = new uint[17]; uint tempCode = 0; for (var bits = 1; bits <= 16; bits++) { tempCode = (tempCode + bitLengthCount[bits - 1]) << 1; nextCode[bits] = tempCode; } var code = new uint[MaxLiteralTreeElements]; for (var i = 0; i < codeLengthArray.Length; i++) { int len = codeLengthArray[i]; if (len > 0) { code[i] = FastEncoderStatics.BitReverse(nextCode[len], len); nextCode[len]++; } } return(code); }
private uint[] CalculateHuffmanCode() { uint[] array = new uint[17]; byte[] array2 = this.codeLengthArray; for (int i = 0; i < array2.Length; i++) { int num = (int)array2[i]; array[num] += 1u; } array[0] = 0u; uint[] array3 = new uint[17]; uint num2 = 0u; for (int j = 1; j <= 16; j++) { num2 = num2 + array[j - 1] << 1; array3[j] = num2; } uint[] array4 = new uint[288]; for (int k = 0; k < this.codeLengthArray.Length; k++) { int num3 = (int)this.codeLengthArray[k]; if (num3 > 0) { array4[k] = FastEncoderStatics.BitReverse(array3[num3], num3); array3[num3] += 1u; } } return(array4); }