| public ReadBits ( int n ) : int | ||
| n | int | Number of bits to return |
| Результат | int | |
public float decode_dc_coefficient(JPEGBinaryReader JPEGStream)
{
int n = this.DCTable.Decode(JPEGStream);
float num2 = JPEGStream.ReadBits(n);
num2 = HuffmanTable.Extend((int) num2, n);
num2 = this.previousDC + num2;
this.previousDC = num2;
return num2;
}
internal void decode_ac_coefficients(JPEGBinaryReader JPEGStream, float[] zz)
{
for (int i = 1; i < 0x40; i++)
{
int t = this.ACTable.Decode(JPEGStream);
int num3 = t >> 4;
t &= 15;
if (t != 0)
{
i += num3;
zz[i] = HuffmanTable.Extend(JPEGStream.ReadBits(t), t);
}
else
{
if (num3 != 15)
{
break;
}
i += 15;
}
}
}
/// <summary>
/// Generated from text on F-23, F.13 - Huffman decoded of AC coefficients
/// on ISO DIS 10918-1. Requirements and Guidelines.
/// </summary>
internal void decode_ac_coefficients(JPEGBinaryReader JPEGStream, float[] zz)
{
for (int k = 1; k < 64; k++)
{
int s = ACTable.Decode(JPEGStream);
int r = s >> 4;
s &= 15;
if (s != 0)
{
k += r;
r = (int)JPEGStream.ReadBits(s);
s = (int)HuffmanTable.Extend(r, s);
zz[k] = s;
}
else
{
if (r != 15)
{
//throw new JPEGMarkerFoundException();
return;
}
k += 15;
}
}
}
/// <summary>
/// Generated from text on F-22, F.2.2.1 - Huffman decoding of DC
/// coefficients on ISO DIS 10918-1. Requirements and Guidelines.
/// </summary>
/// <param name="JPEGStream">Stream that contains huffman bits</param>
/// <returns>DC coefficient</returns>
public float decode_dc_coefficient(JPEGBinaryReader JPEGStream)
{
int t = DCTable.Decode(JPEGStream);
float diff = JPEGStream.ReadBits(t);
diff = HuffmanTable.Extend((int)diff, t);
diff = (previousDC + diff);
previousDC = diff;
return diff;
}
public void DecodeACRefine(JPEGBinaryReader stream, float[] dest)
{
int p1 = 1 << successiveLow;
int m1 = (-1) << successiveLow;
int k = spectralStart;
if (stream.eob_run == 0)
for (; k <= spectralEnd; k++)
{
#region Decode and check S
int s = ACTable.Decode(stream);
int r = s >> 4;
s &= 15;
if (s != 0)
{
if (s != 1)
throw new Exception("Decode Error");
if (stream.ReadBits(1) == 1)
s = p1;
else
s = m1;
}
else
{
if (r != 15)
{
stream.eob_run = 1 << r;
if (r > 0)
stream.eob_run += stream.ReadBits(r);
break;
}
} // if (s != 0)
#endregion
// Apply the update
do
{
if (dest[k] != 0)
{
if (stream.ReadBits(1) == 1)
{
if (((int)dest[k] & p1) == 0)
{
if (dest[k] >= 0)
dest[k] += p1;
else
dest[k] += m1;
}
}
}
else
{
if (--r < 0)
break;
}
k++;
} while (k <= spectralEnd);
if( (s != 0) && k < 64)
{
dest[k] = s;
}
} // for k = start ... end
if (stream.eob_run > 0)
{
for (; k <= spectralEnd; k++)
{
if (dest[k] != 0)
{
if (stream.ReadBits(1) == 1)
{
if (((int)dest[k] & p1) == 0)
{
if (dest[k] >= 0)
dest[k] += p1;
else
dest[k] += m1;
}
}
}
}
stream.eob_run--;
}
}
public void DecodeDCRefine(JPEGBinaryReader stream, float[] dest)
{
if (stream.ReadBits(1) == 1)
{
dest[0] = (int)dest[0] | (1 << successiveLow);
}
}
public void DecodeACFirst(JPEGBinaryReader stream, float[] zz)
{
if (stream.eob_run > 0)
{
stream.eob_run--;
return;
}
for (int k = spectralStart; k <= spectralEnd; k++)
{
int s = ACTable.Decode(stream);
int r = s >> 4;
s &= 15;
if (s != 0)
{
k += r;
r = (int)stream.ReadBits(s);
s = (int)HuffmanTable.Extend(r, s);
zz[k] = s << successiveLow;
}
else
{
if (r != 15)
{
stream.eob_run = 1 << r;
if (r != 0)
stream.eob_run += stream.ReadBits(r);
stream.eob_run--;
break;
}
k += 15;
}
}
}
public void DecodeDCFirst(JPEGBinaryReader stream, float[] dest)
{
float[] datablock = new float[64];
int s = DCTable.Decode(stream);
int r = stream.ReadBits(s);
s = HuffmanTable.Extend(r, s);
s = (int)previousDC + s;
previousDC = s;
dest[0] = s << successiveLow;
}
/// <summary>Figure F.16 - Reads the huffman code bit-by-bit.</summary>
public int Decode(JPEGBinaryReader JPEGStream)
{
int i = 0;
short code = (short)JPEGStream.ReadBits(1);
while (code > maxcode[i])
{
i++;
code <<= 1;
code |= (short)JPEGStream.ReadBits(1);
}
int val = huffval[code + (valptr[i])];
if (val < 0)
val = 256 + val;
return val;
}
public int Decode(JPEGBinaryReader JPEGStream)
{
int index = 0;
short num2 = (short) JPEGStream.ReadBits(1);
while (num2 > this.maxcode[index])
{
index++;
num2 = (short) (num2 << 1);
num2 = (short) (num2 | ((short) JPEGStream.ReadBits(1)));
}
int num3 = this.huffval[num2 + this.valptr[index]];
if (num3 < 0)
{
num3 = 0x100 + num3;
}
return num3;
}
public void DecodeACFirst(JPEGBinaryReader stream, float[] zz)
{
if (stream.eob_run > 0)
{
stream.eob_run--;
}
else
{
for (int i = this.spectralStart; i <= this.spectralEnd; i++)
{
int t = this.ACTable.Decode(stream);
int n = t >> 4;
t &= 15;
if (t != 0)
{
i += n;
t = HuffmanTable.Extend(stream.ReadBits(t), t);
zz[i] = t << this.successiveLow;
}
else
{
if (n != 15)
{
stream.eob_run = ((int) 1) << n;
if (n != 0)
{
stream.eob_run += stream.ReadBits(n);
}
stream.eob_run--;
break;
}
i += 15;
}
}
}
}
public void DecodeDCFirst(JPEGBinaryReader stream, float[] dest)
{
float[] numArray = new float[0x40];
int t = this.DCTable.Decode(stream);
t = HuffmanTable.Extend(stream.ReadBits(t), t);
t = ((int) this.previousDC) + t;
this.previousDC = t;
dest[0] = t << this.successiveLow;
}
public void DecodeACRefine(JPEGBinaryReader stream, float[] dest)
{
int num = ((int) 1) << this.successiveLow;
int num2 = ((int) (-1)) << this.successiveLow;
int spectralStart = this.spectralStart;
if (stream.eob_run == 0)
{
while (spectralStart <= this.spectralEnd)
{
int num4 = this.ACTable.Decode(stream);
int n = num4 >> 4;
num4 &= 15;
if (num4 != 0)
{
if (num4 != 1)
{
throw new Exception("Decode Error");
}
if (stream.ReadBits(1) == 1)
{
num4 = num;
}
else
{
num4 = num2;
}
}
else if (n != 15)
{
stream.eob_run = ((int) 1) << n;
if (n > 0)
{
stream.eob_run += stream.ReadBits(n);
}
break;
}
do
{
if (dest[spectralStart] != 0f)
{
if ((stream.ReadBits(1) == 1) && ((((int) dest[spectralStart]) & num) == 0))
{
if (dest[spectralStart] >= 0f)
{
dest[spectralStart] += num;
}
else
{
dest[spectralStart] += num2;
}
}
}
else if (--n < 0)
{
break;
}
spectralStart++;
}
while (spectralStart <= this.spectralEnd);
if ((num4 != 0) && (spectralStart < 0x40))
{
dest[spectralStart] = num4;
}
spectralStart++;
}
}
if (stream.eob_run > 0)
{
while (spectralStart <= this.spectralEnd)
{
if (((dest[spectralStart] != 0f) && (stream.ReadBits(1) == 1)) && ((((int) dest[spectralStart]) & num) == 0))
{
if (dest[spectralStart] >= 0f)
{
dest[spectralStart] += num;
}
else
{
dest[spectralStart] += num2;
}
}
spectralStart++;
}
stream.eob_run--;
}
}
){kind=link}