private IEnumerable <Tuple <int, int> > FindBreaks(IBitEncoding e, int imin, Code min, int imax, Code max)
{
if (imax == imin + 1)
{
yield return(Tuple.Create(imax, max.Length));
yield break;
}
int imid = imin + (imax - imin) / 2;
Code mid = e.GetCode(imid);
if (mid.Length > min.Length)
{
foreach (var k in FindBreaks(e, imin, min, imid, mid))
{
yield return(k);
}
}
if (max.Length > mid.Length)
{
foreach (var k in FindBreaks(e, imid, mid, imax, max))
{
yield return(k);
}
}
}
internal Golomb(int divisor)
{
if (divisor < 2)
{
throw new ArgumentOutOfRangeException();
}
this.divisor = divisor;
remainderCode = Codes.TruncatedBinary(divisor);
var r = remainderCode.MaxEncodable;
maxEncodable = divisor * (63 - remainderCode.GetCode(r).Length) + r;
}
private IEnumerable <Tuple <int, int> > FindBreaks(IBitEncoding e)
{
Code min = e.GetCode(e.MinEncodable);
yield return(Tuple.Create(e.MinEncodable, min.Length));
Code max = e.GetCode(e.MaxEncodable);
foreach (var k in FindBreaks(e, e.MinEncodable, min, e.MaxEncodable, max))
{
yield return(k);
}
}
internal BaseN(int n)
{
this.n = n;
if (Bits.IsPowerOf2(n))
{
encoding = Codes.FixedWidth(Bits.FloorLog2(n) + 1);
}
else
{
encoding = Codes.TruncatedBinary(n);
}
}
private void EncodingTest(IBitEncoding encoding)
{
var writer = new BitWriter(1000);
var values = new List <int>();
var g = new Generator(encoding.GetType().Name);
for (int i = 0; i < 1000; i++)
{
int v = g.Int32() >> g.Int32(32);
if (v < encoding.MinEncodable || v > encoding.MaxEncodable)
{
continue;
}
values.Add(v);
if (i < 500)
{
writer.Write(encoding.GetCode(v));
}
else
{
encoding.Write(writer, v);
}
}
var buffer = writer.ToArray();
var reader = new BitReader(buffer);
for (int i = 0; i < values.Count; i++)
{
int v = encoding.Read(reader);
Assert.AreEqual(values[i], v);
}
try
{
encoding.GetCode(encoding.MinEncodable - 1);
Assert.Fail("Expected ArgumentOutOfRangeException");
}
catch (Exception e)
{
Assert.AreEqual("ArgumentOutOfRangeException", e.GetType().Name);
}
}
/// <summary>
/// Reads a <see cref="System.Int32"/> value using the specified <see cref="IBitEncoding"/>.
/// </summary>
public int Read(IBitEncoding encoding)
{
return(encoding.Read(this));
}
/// <summary>
/// Use this <see cref="IBitEncoding"/> to write a <see cref="System.Int32"/> value
/// to the specified <see cref="BitWriter"/>.
/// </summary>
public static void Write(this IBitEncoding encoding, BitWriter writer, int value)
{
writer.Write(encoding, value);
}
/// <summary>
/// Write a <see cref="System.Int32"/> using the specified <see cref="IBitEncoding"/>.
/// </summary>
public void Write(IBitEncoding encoding, int value)
{
Write(encoding.GetCode(value));
}