2018-08-31 06:12:33 +04:00

904 lines
33 KiB
C#

//! \file ImagePB3.cs
//! \date Wed Dec 02 13:55:45 2015
//! \brief Cmvs engine image format.
//
// Copyright (C) 2015-2016 by morkt
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//
using GameRes.Utility;
using System;
using System.ComponentModel.Composition;
using System.IO;
using System.Linq;
using System.Windows.Media;
using System.Collections.Generic;
namespace GameRes.Formats.Purple
{
internal class PbMetaData : ImageMetaData
{
public int Type;
public int InputSize;
}
internal class Pb3MetaData : PbMetaData
{
public int SubType;
}
[Export(typeof(ImageFormat))]
public class Pb3Format : ImageFormat
{
public override string Tag { get { return "PB3"; } }
public override string Description { get { return "Purple Software image format"; } }
public override uint Signature { get { return 0x42334250; } } // 'PB3B'
public override ImageMetaData ReadMetaData (IBinaryStream stream)
{
stream.Position = 4;
int input_size = stream.ReadInt32();
stream.Position = 0x18;
int t2 = stream.ReadInt32();
int t1 = stream.ReadUInt16();
uint width = stream.ReadUInt16();
uint height = stream.ReadUInt16();
int bpp = stream.ReadUInt16();
return new Pb3MetaData
{
Width = width,
Height = height,
BPP = bpp,
Type = t1,
SubType = t2,
InputSize = input_size,
};
}
public override ImageData Read (IBinaryStream stream, ImageMetaData info)
{
var reader = new Pb3Reader (stream.AsStream, (Pb3MetaData)info);
reader.Unpack();
return ImageData.Create (info, reader.Format, null, reader.Data);
}
public override void Write (Stream file, ImageData image)
{
throw new System.NotImplementedException ("Pb3Format.Write not implemented");
}
}
internal class PbReaderBase
{
protected PbMetaData m_info;
protected byte[] m_input;
protected byte[] m_output;
protected byte[] m_lzss_frame = new byte[0x800];
protected int m_stride;
protected PbReaderBase (PbMetaData info)
{
m_info = info;
}
public PixelFormat Format { get; protected set; }
public byte[] Data { get { return m_output; } }
internal void LzssResetFrame ()
{
for (int i = 0; i < 0x7DE; ++i)
m_lzss_frame[i] = 0;
}
internal void LzssUnpack (int bit_src, int data_src, byte[] output, int output_size)
{
int dst = 0;
int bit_mask = 0x80;
int frame_offset = 0x7DE;
while (dst < output_size)
{
if (0 == bit_mask)
{
bit_mask = 0x80;
++bit_src;
}
if (0 != (bit_mask & m_input[bit_src]))
{
int v = LittleEndian.ToUInt16 (m_input, data_src);
data_src += 2;
int count = (v & 0x1F) + 3;
int offset = v >> 5;
for (int i = 0; i < count; ++i)
{
byte b = m_lzss_frame[(i + offset) & 0x7FF];
output[dst++] = b;
m_lzss_frame[frame_offset++] = b;
frame_offset &= 0x7FF;
}
}
else
{
byte b = m_input[data_src++];
output[dst++] = b;
m_lzss_frame[frame_offset++] = b;
frame_offset &= 0x7FF;
}
bit_mask >>= 1;
}
}
internal void UnpackJbp (int jbp_pos, int alpha_pos)
{
var jbp = new JbpReader (m_input, jbp_pos);
m_output = jbp.Unpack();
if (m_stride != jbp.Stride)
{
int src_stride = jbp.Stride;
int src = src_stride;
int dst = m_stride;
for (uint y = 1; y < m_info.Height; ++y)
{
Buffer.BlockCopy (m_output, src, m_output, dst, m_stride);
src += src_stride;
dst += m_stride;
}
}
if (32 == m_info.BPP && alpha_pos > 0)
{
int dst = 3;
int output_end = m_stride * (int)m_info.Height;
while (dst < output_end)
{
byte alpha = m_input[alpha_pos++];
if (0 != alpha && 0xFF != alpha)
{
m_output[dst] = alpha;
dst += 4;
}
else
{
int count = m_input[alpha_pos++];
while (count --> 0)
{
m_output[dst] = alpha;
dst += 4;
}
}
}
}
else
{
Format = PixelFormats.Bgr32;
}
}
}
internal sealed class Pb3Reader : PbReaderBase
{
int m_channels;
public Pb3Reader (Stream input, Pb3MetaData info) : base (info)
{
if (info.Type == 1 && info.SubType != 0x10)
throw new NotSupportedException();
if (3 == m_info.Type || 2 == m_info.Type)
m_input = new byte[input.Length];
else
m_input = new byte[m_info.InputSize];
if (m_input.Length != input.Read (m_input, 0, m_input.Length))
throw new EndOfStreamException();
m_channels = m_info.BPP / 8;
m_stride = 4 * (int)m_info.Width;
Format = m_channels < 4 ? PixelFormats.Bgr32 : PixelFormats.Bgra32;
// output array created by unpack methods as needed.
}
public void Unpack ()
{
switch (m_info.Type)
{
default: throw new InvalidEncryptionScheme();
case 1: UnpackV1(); break;
case 5: UnpackV5(); break;
case 8:
case 6: UnpackV6(); break;
case 2:
case 3: UnpackJbp (0x34, m_input.ToInt32 (0x2C)); break;
case 4:
case 7: throw new NotSupportedException(string.Format ("PB3 v{0} images not supported", m_info.Type));
}
}
void UnpackV1 ()
{
int width = (int)m_info.Width;
int height = (int)m_info.Height;
m_output = new byte[m_stride * height];
int x_blocks = width >> 4;
if (0 != (width & 0xF))
++x_blocks;
int y_blocks = height >> 4;
if (0 != (height & 0xF))
++y_blocks;
int plane_size = width * height;
byte[] plane = new byte[plane_size];
int data1 = LittleEndian.ToInt32 (m_input, 0x2C);
int data2 = LittleEndian.ToInt32 (m_input, 0x30);
for (int channel = 0; channel < m_channels; ++channel)
{
int channel_offset = 4 * m_channels;
for (int i = 0; i < channel; ++i)
channel_offset += LittleEndian.ToInt32 (m_input, data1 + 4*i);
int v21 = data1 + channel_offset;
int bit_src = v21 + 12 + LittleEndian.ToInt32 (m_input, v21) + LittleEndian.ToInt32 (m_input, v21+4);
int channel_size = LittleEndian.ToInt32 (m_input, v21 + 8);
channel_offset = 4 * m_channels;
for (int i = 0; i < channel; ++i)
channel_offset += LittleEndian.ToInt32 (m_input, data2 + 4*i);
int data_src = data2 + channel_offset;
LzssResetFrame();
LzssUnpack (bit_src, data_src, plane, channel_size);
if (0 == y_blocks || 0 == x_blocks)
continue;
int plane_src = 0;
bit_src = v21 + 12;
int bit_mask = 128;
data_src = bit_src + LittleEndian.ToInt32 (m_input, v21);
int v68 = 16;
for (int y = 0; y < y_blocks; ++y)
{
int row = 16 * y;
int v66 = 16;
int dst_origin = m_stride * row + channel; // within m_output
for (int x = 0; x < x_blocks; ++x)
{
int dst = dst_origin;
int block_width = v66 > width ? width - 16 * x : 16;
int block_height = v68 > height ? height - row : 16;
if (0 == bit_mask)
{
++bit_src;
bit_mask = 128;
}
if (0 != (bit_mask & m_input[bit_src]))
{
byte b = m_input[data_src++];
for (int j = 0; j < block_height; ++j)
{
int v49 = dst;
for (int i = 0; i < block_width; ++i)
{
m_output[v49] = b;
v49 += 4;
}
dst += m_stride;
}
}
else
{
for (int j = 0; j < block_height; ++j)
{
int v49 = dst;
for (int i = 0; i < block_width; ++i)
{
m_output[v49] = plane[plane_src++];
v49 += 4;
}
dst += m_stride;
}
}
bit_mask >>= 1;
v66 += 16;
dst_origin += 64;
}
v68 += 16;
}
}
}
void UnpackV5 ()
{
m_output = new byte[m_stride * (int)m_info.Height];
for (int i = 0; i < 4; ++i)
{
int bit_src = 0x54 + LittleEndian.ToInt32 (m_input, 8 * i + 0x34);
int data_src = 0x54 + LittleEndian.ToInt32 (m_input, 8 * i + 0x38);
LzssResetFrame();
int frame_offset = 0x7DE;
byte accum = 0;
int bit_mask = 128;
int dst = i;
while (dst < m_output.Length)
{
if (0 == bit_mask)
{
++bit_src;
bit_mask = 128;
}
if (0 != (bit_mask & m_input[bit_src]))
{
int v = LittleEndian.ToUInt16 (m_input, data_src);
data_src += 2;
int count = (v & 0x1F) + 3;
int offset = v >> 5;
for (int k = 0; k < count; ++k)
{
byte b = m_lzss_frame[(k + offset) & 0x7FF];
m_lzss_frame[frame_offset++] = b;
accum += b;
m_output[dst] = accum;
dst += 4;
frame_offset &= 0x7FF;
}
}
else
{
byte b = m_input[data_src++];
m_lzss_frame[frame_offset++] = b;
accum += b;
m_output[dst] = accum;
dst += 4;
frame_offset &= 0x7FF;
}
bit_mask >>= 1;
}
}
}
static readonly byte[] NameKeyV6 = {
0xA6, 0x75, 0xF3, 0x9C, 0xC5, 0x69, 0x78, 0xA3, 0x3E, 0xA5, 0x4F, 0x79, 0x59, 0xFE, 0x3A, 0xC7,
};
void UnpackV6 ()
{
var name_bytes = new byte[0x20];
int name_offset = 0x34;
int i;
for (i = 0; i < 0x20; ++i)
{
name_bytes[i] = (byte)(m_input[name_offset+i] ^ NameKeyV6[i & 0xF]);
if (0 == name_bytes[i])
break;
}
m_output = LoadBaseImage (Encodings.cp932.GetString (name_bytes, 0, i) + ".pb3");
BlendInput();
}
byte[] LoadBaseImage (string name)
{
// judging by the code, files with "pb3" extension could as well contain PNG or BMP images,
// so we couldn't just shortcut to another instance of Pb3Reader here.
var path = VFS.GetDirectoryName (m_info.FileName);
name = VFS.CombinePath (path, name);
if (name.Equals (m_info.FileName, StringComparison.InvariantCultureIgnoreCase))
throw new InvalidFormatException();
// two files referencing each other still could create infinite recursion
using (var base_file = VFS.OpenBinaryStream (name))
{
var image_data = ImageFormat.Read (base_file);
int stride = image_data.Bitmap.PixelWidth * 4;
var pixels = new byte[stride * image_data.Bitmap.PixelHeight];
image_data.Bitmap.CopyPixels (pixels, stride, 0);
return pixels;
}
}
void BlendInput ()
{
int bit_src = 0x20 + LittleEndian.ToInt32 (m_input, 0xC);
int data_src = bit_src + LittleEndian.ToInt32 (m_input, 0x2C);
int overlay_size = LittleEndian.ToInt32 (m_input, 0x18);
var overlay = new byte[overlay_size];
LzssUnpack (bit_src, data_src, overlay, overlay_size);
int width = (int)m_info.Width;
int height = (int)m_info.Height;
bit_src = 8; // within overlay
data_src = 8 + LittleEndian.ToInt32 (overlay, 0); // within overlay
int bit_mask = 0x80;
int x_blocks = width >> 3;
if (0 != (width & 7))
++x_blocks;
int y_blocks = height >> 3;
if (0 != (height & 7))
++y_blocks;
if (0 == x_blocks)
return;
int h = 0;
int dst_origin = 0;
while (y_blocks > 0)
{
int w = 0;
for (int x = 0; x < x_blocks; ++x)
{
if (0 == bit_mask)
{
++bit_src;
bit_mask = 0x80;
}
if (0 == (bit_mask & overlay[bit_src]))
{
int dst = 8 * (dst_origin + 4 * x); // within m_output
int x_count = Math.Min (8, width - w);
int y_count = Math.Min (8, height - h);
for (int v30 = y_count; v30 > 0; --v30)
{
int count = 4 * x_count;
Buffer.BlockCopy (overlay, data_src, m_output, dst, count);
data_src += count;
dst += m_stride;
}
}
bit_mask >>= 1;
w += 8;
}
dst_origin += m_stride;
h += 8;
--y_blocks;
}
}
}
public sealed class JbpReader
{
byte[] m_input;
byte[] m_output;
int m_data_pos;
uint m_format;
int m_aligned_width;
int m_aligned_height;
int m_stride;
int m_blocks_x;
int m_blocks_y;
int m_dc_bits;
int m_ac_bits;
public int Width { get { return m_aligned_width; } }
public int Height { get { return m_aligned_height; } }
public int Stride { get { return m_stride; } }
public JbpReader (byte[] input, int offset)
{
m_input = input;
m_data_pos = LittleEndian.ToInt32 (input, offset+4) + offset;
m_format = LittleEndian.ToUInt32 (input, offset+8);
int width = LittleEndian.ToUInt16 (input, offset+0x10);
int height = LittleEndian.ToUInt16 (input, offset+0x12);
m_dc_bits = LittleEndian.ToInt32 (input, offset+0x1C);
m_ac_bits = LittleEndian.ToInt32 (input, offset+0x20);
switch ((m_format >> 28) & 3)
{
case 0:
m_aligned_width = (width + 7) & ~7;
m_aligned_height = (height + 7) & ~7;
break;
case 1:
m_aligned_width = (width + 0xF) & ~0xF;
m_aligned_height = (height + 0xF) & ~0xF;
break;
case 2:
m_aligned_width = (width + 0x1F) & ~0x1F;
m_aligned_height = (height + 0x0F) & ~0x0F;
break;
default:
throw new InvalidFormatException();
}
m_blocks_x = m_aligned_width >> 4;
m_blocks_y = m_aligned_height >> 4;
m_stride = 4 * m_aligned_width;
m_output = new byte[m_stride * m_aligned_height];
}
short[] quant_y = new short[0x40];
short[] quant_c = new short[0x40];
JBitStream bits_dc;
JBitStream bits_ac;
HuffmanTree tree_dc;
HuffmanTree tree_ac;
public byte[] Unpack ()
{
var tree_data = new byte[0x10];
int tree_pos = m_data_pos+0x80;
for (int i = 0; i < 0x10; ++i)
tree_data[i] = (byte)(m_input[tree_pos+i] + 1);
var freq = new uint[0x20];
Buffer.BlockCopy (m_input, m_data_pos, freq, 0, 0x40);
tree_dc = new HuffmanTree (tree_data, freq);
Buffer.BlockCopy (m_input, m_data_pos+0x40, freq, 0, 0x40);
tree_ac = new HuffmanTree (tree_data, freq);
int quant_pos = tree_pos+0x10;
if (0 != (m_format & 0x8000000))
{
for (int i = 0; i < 0x40; ++i)
{
quant_y[i] = m_input[quant_pos+i];
quant_c[i] = m_input[quant_pos+i+0x40];
}
}
int bits_offset = quant_pos + 0x80;
bits_dc = new JBitStream (m_input, bits_offset, m_dc_bits);
bits_ac = new JBitStream (m_input, bits_offset + m_dc_bits, m_ac_bits);
Decode();
return m_output;
}
static byte[] ZigzagOrder = new byte[64]
{
1, 8, 16, 9, 2, 3, 10, 17,
24, 32, 25, 18, 11, 4, 5, 12,
19, 26, 33, 40, 48, 41, 34, 27,
20, 13, 6, 7, 14, 21, 28, 35,
42, 49, 56, 57, 50, 43, 36, 29,
22, 15, 23, 30, 37, 44, 51, 58,
59, 52, 45, 38, 31, 39, 46, 53,
60, 61, 54, 47, 55, 62, 63, 0
};
void Decode ()
{
int total_blocks = m_blocks_x * m_blocks_y;
var blocks = new short[total_blocks, 6];
uint prev_v = 0;
for (int i = 0; i < total_blocks; ++i)
for (int j = 0; j < 6; ++j)
{
int bit_count = tree_dc.Read (bits_dc);
uint v = (uint)bits_dc.GetBits (bit_count);
if (v < (1u << (bit_count - 1)))
v -= (1u << bit_count) - 1;
prev_v += v;
blocks[i,j] = (short)prev_v;
}
var dct_table = new short[6][];
for (int i = 0; i < 6; ++i)
dct_table[i] = new short[64];
for (int y = 0; y < m_blocks_y; ++y)
{
int dst1 = y * m_stride * 16;
int dst2 = dst1 + m_stride * 9;
for (int x = 0; x < m_blocks_x; ++x)
{
for (int j = 0; j < 6; ++j)
for (int k = 0; k < 64; ++k)
dct_table[j][k] = 0;
for (int n = 0; n < 6; ++n)
{
dct_table[n][0] = blocks[y * m_blocks_x + x, n];
for (int i = 0; i < 63;)
{
int bit_count = tree_ac.Read (bits_ac);
if (15 == bit_count)
break;
if (0 == bit_count)
{
int node_idx = 0;
while (0 != bits_ac.GetNextBit())
node_idx++;
i += tree_ac.Base[node_idx];
}
else
{
uint v = (uint)bits_ac.GetBits (bit_count);
if (v < (1u << (bit_count - 1)))
v -= (1u << bit_count) - 1;
dct_table[n][ZigzagOrder[i]] = (short)v;
++i;
}
}
}
Dct (dct_table[0], quant_y);
Dct (dct_table[1], quant_y);
Dct (dct_table[2], quant_y);
Dct (dct_table[3], quant_y);
Dct (dct_table[4], quant_c);
Dct (dct_table[5], quant_c);
Ycc2Rgb (dst1, dst1+m_stride, dct_table[0], dct_table[4], dct_table[5], 0);
Ycc2Rgb (dst1+32, dst1+m_stride+32, dct_table[1], dct_table[4], dct_table[5], 4);
Ycc2Rgb (dst2-m_stride, dst2, dct_table[2], dct_table[4], dct_table[5], 32);
Ycc2Rgb (dst2-m_stride+32, dst2+32, dct_table[3], dct_table[4], dct_table[5], 36);
dst1 += 64;
dst2 += 64;
}
}
}
void Dct (short[] dct_table, short[] quant)
{
int a, b, c, d;
int w, x, y, z;
int s, t, u, v, n;
int p = 0;
int q = 0;
for (int i = 0; i < 8; ++i)
{
if (dct_table[p+0x08] == 0 && dct_table[p+0x10] == 0 &&
dct_table[p+0x18] == 0 && dct_table[p+0x20] == 0 &&
dct_table[p+0x28] == 0 && dct_table[p+0x30] == 0 &&
dct_table[p+0x38] == 0)
{
dct_table[p] = dct_table[p+0x08] =
dct_table[p+0x10] = dct_table[p+0x18] =
dct_table[p+0x20] = dct_table[p+0x28] =
dct_table[p+0x30] = dct_table[p+0x38] = (short)(dct_table[p] * quant[q]);
}
else
{
c = quant[q+0x10] * dct_table[p+0x10];
d = quant[q+0x30] * dct_table[p+0x30];
x = ((c + d) * 35467) >> 16;
c = ((c * 50159) >> 16) + x;
d = ((d * -121094) >> 16) + x;
a = dct_table[p+0x00] * quant[q+0x00];
b = dct_table[p+0x20] * quant[q+0x20];
w = a + b + c;
x = a + b - c;
y = a - b + d;
z = a - b - d;
c = dct_table[p+0x38] * quant[q+0x38];
d = dct_table[p+0x28] * quant[q+0x28];
a = dct_table[p+0x18] * quant[q+0x18];
b = dct_table[p+0x08] * quant[q+0x08];
n = ((a + b + c + d) * 77062) >> 16;
u = n + ((c * 19571) >> 16) + (((c + a) * -128553) >> 16) + (((c + b) * -58980) >> 16);
v = n + ((d * 134553) >> 16) + (((d + b) * -25570) >> 16) + (((d + a) * -167963) >> 16);
t = n + ((b * 98390) >> 16) + (((d + b) * -25570) >> 16) + (((c + b) * -58980) >> 16);
s = n + ((a * 201373) >> 16) + (((c + a) * -128553) >> 16) + (((d + a) * -167963) >> 16);
dct_table[p] = (short)(w + t);
dct_table[p+0x38] = (short)(w - t);
dct_table[p+0x08] = (short)(y + s);
dct_table[p+0x30] = (short)(y - s);
dct_table[p+0x10] = (short)(z + v);
dct_table[p+0x28] = (short)(z - v);
dct_table[p+0x18] = (short)(x + u);
dct_table[p+0x20] = (short)(x - u);
}
p++;
q++;
}
p = 0;
for (int i = 0; i < 8; ++i)
{
a = dct_table[p];
c = dct_table[p+2];
b = dct_table[p+4];
d = dct_table[p+6];
x = ((c + d) * 35467) >> 16;
c = ((c * 50159) >> 16) + x;
d = ((d * -121094) >> 16) + x;
w = a + b + c;
x = a + b - c;
y = a - b + d;
z = a - b - d;
d = dct_table[p+5];
b = dct_table[p+1];
c = dct_table[p+7];
a = dct_table[p+3];
n = ((a + b + c + d) * 77062) >> 16;
s = n + ((a * 201373) >> 16) + (((a + c) * -128553) >> 16) + (((a + d) * -167963) >> 16);
t = n + ((b * 98390) >> 16) + (((b + c) * -58980) >> 16) + (((b + d) * -25570) >> 16);
u = n + ((c * 19571) >> 16) + (((b + c) * -58980) >> 16) + (((a + c) * -128553) >> 16);
v = n + ((d * 134553) >> 16) + (((b + d) * -25570) >> 16) + (((a + d) * -167963) >> 16);
dct_table[p ] = (short)((w + t) >> 3);
dct_table[p+7] = (short)((w - t) >> 3);
dct_table[p+1] = (short)((y + s) >> 3);
dct_table[p+6] = (short)((y - s) >> 3);
dct_table[p+2] = (short)((z + v) >> 3);
dct_table[p+5] = (short)((z - v) >> 3);
dct_table[p+3] = (short)((x + u) >> 3);
dct_table[p+4] = (short)((x - u) >> 3);
p += 8;
}
}
void Ycc2Rgb (int dc, int ac, short[] dct_y, short[] dct_cb, short[] dct_cr, int cbcr_src)
{
int y_src = 0;
for (int y = 0; y < 4; ++y)
{
for (int x = 0; x < 4; ++x)
{
var cb = dct_cb[cbcr_src];
var cr = dct_cr[cbcr_src];
var r = ((cr * 0x166F0) >> 16);
var g = ((cb * 0x5810) >> 16) + ((cr * 0xB6C0) >> 16);
var b = ((cb * 0x1C590) >> 16);
var c0 = dct_y[y_src ] + 0x180;
var c1 = dct_y[y_src+1] + 0x180;
var c8 = dct_y[y_src+8] + 0x180;
var c9 = dct_y[y_src+9] + 0x180;
m_output[dc] = Clamp (c0 + b);
m_output[ac+1-m_stride] = Clamp (c0 - g);
m_output[ac+2-m_stride] = Clamp (c0 + r);
m_output[ac+4-m_stride] = Clamp (c1 + b);
m_output[ac+5-m_stride] = Clamp (c1 - g);
m_output[ac+6-m_stride] = Clamp (c1 + r);
m_output[ac] = Clamp (c8 + b);
m_output[ac+1] = Clamp (c8 - g);
m_output[ac+2] = Clamp (c8 + r);
m_output[ac+4] = Clamp (c9 + b);
m_output[ac+5] = Clamp (c9 - g);
m_output[ac+6] = Clamp (c9 + r);
y_src += 2;
dc += 8;
ac += 8;
cbcr_src++;
}
dc += m_stride * 2 - 32;
ac += m_stride * 2 - 32;
y_src += 8;
cbcr_src += 4;
}
}
static byte[] YccClampTable = Enumerable.Repeat<byte> (0, 0x100)
.Concat (Enumerable.Range (0, 0x100).Select (x => (byte)x))
.Concat (Enumerable.Repeat<byte> (0xFF, 0x100)).ToArray();
static byte Clamp (int c)
{
return YccClampTable[c];
}
internal class HuffmanTree
{
public byte[] Base;
private int[] Nodes = new int[0x400];
private int Root;
public int LeafCount { get { return Base.Length; } }
const uint MaxFreq = 2100000000u;
public HuffmanTree (byte[] input, uint[] freq)
{
Base = input;
int depth = Base.Length;
for (;;)
{
int l = -1;
uint min = MaxFreq - 1;
for (int i = 0; i < depth; ++i)
{
if (freq[i] < min)
{
min = freq[i];
l = i;
}
}
int r = -1;
min = MaxFreq - 1;
for (int i = 0; i < depth; ++i)
{
if ((i != l) && (freq[i] < min))
{
min = freq[i];
r = i;
}
}
if (l < 0 || r < 0)
break;
Nodes[depth] = l;
Nodes[depth+0x200] = r;
freq[depth++] = freq[l] + freq[r];
freq[l] = MaxFreq;
freq[r] = MaxFreq;
}
Root = depth - 1;
}
public int Read (JBitStream bits)
{
int v = Root;
while (v >= LeafCount)
v = Nodes[v + (bits.GetNextBit() << 9)];
return v;
}
}
internal class JBitStream
{
byte[] m_input;
int m_pos;
int m_end;
public JBitStream (byte[] input, int offset, int length)
{
m_input = input;
m_pos = offset;
m_end = offset + length;
}
int m_bits = 0;
int m_cached_bits = 0;
public int GetBits (int count)
{
while (m_cached_bits < count)
{
if (m_pos >= m_end)
throw new EndOfStreamException();
m_bits = (m_bits << 8) | ReverseByteBits (m_input[m_pos++]);
m_cached_bits += 8;
}
int mask = (1 << count) - 1;
m_cached_bits -= count;
return (m_bits >> m_cached_bits) & mask;
}
public int GetNextBit ()
{
return GetBits (1);
}
int ReverseByteBits (int x)
{
x = (x & 0xAA) >> 1 | (x & 0x55) << 1;
x = (x & 0xCC) >> 2 | (x & 0x33) << 2;
return (x >> 4 | x << 4) & 0xFF;
}
}
}
}