internal static DecoderResult Decode(byte[] bytes,
Version version,
ErrorCorrectionLevel ecLevel)
{
var bits = new BitSource(bytes);
var result = new StringBuilder(50);
var byteSegments = new List <byte[]>(1);
var symbolSequence = -1;
var parityData = -1;
try
{
CharacterSetECI currentCharacterSetECI = null;
bool fc1InEffect = false;
Mode mode;
do
{
// While still another segment to read...
if (bits.Available() < 4)
{
// OK, assume we're done. Really, a TERMINATOR mode should have been recorded here
mode = Mode.TERMINATOR;
}
else
{
try
{
mode = Mode.ForBits(bits.ReadBits(4)); // mode is encoded by 4 bits
}
catch (ArgumentException)
{
return(null);
}
}
switch (mode.Name)
{
case Mode.Names.TERMINATOR:
break;
case Mode.Names.FNC1_FIRST_POSITION:
case Mode.Names.FNC1_SECOND_POSITION:
// We do little with FNC1 except alter the parsed result a bit according to the spec
fc1InEffect = true;
break;
case Mode.Names.STRUCTURED_APPEND:
if (bits.Available() < 16)
{
return(null);
}
// not really supported; but sequence number and parity is added later to the result metadata
// Read next 8 bits (symbol sequence #) and 8 bits (parity data), then continue
symbolSequence = bits.ReadBits(8);
parityData = bits.ReadBits(8);
break;
case Mode.Names.ECI:
// Count doesn't apply to ECI
int value = ParseECIValue(bits);
currentCharacterSetECI = CharacterSetECI.GetCharacterSetECIByValue(value);
if (currentCharacterSetECI == null)
{
return(null);
}
break;
case Mode.Names.HANZI:
// First handle Hanzi mode which does not start with character count
//chinese mode contains a sub set indicator right after mode indicator
int subset = bits.ReadBits(4);
int countHanzi = bits.ReadBits(mode.GetCharacterCountBits(version));
if (subset == GB2312_SUBSET)
{
if (!DecodeHanziSegment(bits, result, countHanzi))
{
return(null);
}
}
break;
default:
// "Normal" QR code modes:
// How many characters will follow, encoded in this mode?
int count = bits.ReadBits(mode.GetCharacterCountBits(version));
switch (mode.Name)
{
case Mode.Names.NUMERIC:
if (!DecodeNumericSegment(bits, result, count))
{
return(null);
}
break;
case Mode.Names.ALPHANUMERIC:
if (!DecodeAlphanumericSegment(bits, result, count, fc1InEffect))
{
return(null);
}
break;
case Mode.Names.BYTE:
if (!DecodeByteSegment(bits, result, count, currentCharacterSetECI, byteSegments))
{
return(null);
}
break;
case Mode.Names.KANJI:
if (!DecodeKanjiSegment(bits, result, count))
{
return(null);
}
break;
default:
return(null);
}
break;
}
} while (mode != Mode.TERMINATOR);
}
catch (ArgumentException)
{
// from readBits() calls
return(null);
}
var resultString = result.ToString().Replace("\r\n", "\n").Replace("\n", Environment.NewLine);
return(new DecoderResult(bytes, resultString));
}
internal static DecoderResult Decode(sbyte[] bytes, Version version, ErrorCorrectionLevel ecLevel)
{
BitSource bits = new BitSource(bytes);
StringBuilder result = new StringBuilder(50);
CharacterSetECI currentCharacterSetECI = null;
bool fc1InEffect = false;
System.Collections.ArrayList byteSegments = System.Collections.ArrayList.Synchronized(new System.Collections.ArrayList(1));
Mode mode;
do
{
// While still another segment to read...
if (bits.Available() < 4)
{
// OK, assume we're done. Really, a TERMINATOR mode should have been recorded here
mode = Mode.TERMINATOR;
}
else
{
try
{
mode = Mode.ForBits(bits.ReadBits(4)); // mode is encoded by 4 bits
}
catch (ArgumentException)
{
throw ReaderException.Instance;
}
}
if (!mode.Equals(Mode.TERMINATOR))
{
if (mode.Equals(Mode.FNC1_FIRST_POSITION) || mode.Equals(Mode.FNC1_SECOND_POSITION))
{
// We do little with FNC1 except alter the parsed result a bit according to the spec
fc1InEffect = true;
}
else if (mode.Equals(Mode.STRUCTURED_APPEND))
{
// not really supported; all we do is ignore it
// Read next 8 bits (symbol sequence #) and 8 bits (parity data), then continue
bits.ReadBits(16);
}
else if (mode.Equals(Mode.ECI))
{
// Count doesn't apply to ECI
int value_Renamed = ParseECIValue(bits);
currentCharacterSetECI = CharacterSetECI.GetCharacterSetECIByValue(value_Renamed);
if (currentCharacterSetECI == null)
{
throw ReaderException.Instance;
}
}
else
{
// How many characters will follow, encoded in this mode?
int count = bits.ReadBits(mode.GetCharacterCountBits(version));
if (mode.Equals(Mode.NUMERIC))
{
DecodeNumericSegment(bits, result, count);
}
else if (mode.Equals(Mode.ALPHANUMERIC))
{
DecodeAlphanumericSegment(bits, result, count, fc1InEffect);
}
else if (mode.Equals(Mode.BYTE))
{
DecodeByteSegment(bits, result, count, currentCharacterSetECI, byteSegments);
}
else if (mode.Equals(Mode.KANJI))
{
DecodeKanjiSegment(bits, result, count);
}
else
{
throw ReaderException.Instance;
}
}
}
}while (!mode.Equals(Mode.TERMINATOR));
return(new DecoderResult(bytes, result.ToString(), (byteSegments.Count == 0)?null:byteSegments, ecLevel));
}
