ImageData ReadV5(Stream stream, TlgMetaData info)
{
using (var src = new ArcView.Reader(stream))
{
int width = (int)info.Width;
int height = (int)info.Height;
int colors = info.BPP / 8;
int blockheight = src.ReadInt32();
int blockcount = (height - 1) / blockheight + 1;
// skip block size section
src.BaseStream.Seek(blockcount * 4, SeekOrigin.Current);
int stride = width * 4;
var image_bits = new byte[height * stride];
var text = new byte[4096];
for (int i = 0; i < 4096; ++i)
{
text[i] = 0;
}
var inbuf = new byte[blockheight * width + 10];
byte [][] outbuf = new byte[4][];
for (int i = 0; i < colors; i++)
{
outbuf[i] = new byte[blockheight * width + 10];
}
int z = 0;
int prevline = -1;
for (int y_blk = 0; y_blk < height; y_blk += blockheight)
{
// read file and decompress
for (int c = 0; c < colors; c++)
{
byte mark = src.ReadByte();
int size;
size = src.ReadInt32();
if (mark == 0)
{
// modified LZSS compressed data
if (size != src.Read(inbuf, 0, size))
{
return(null);
}
z = TVPTLG5DecompressSlide(outbuf[c], inbuf, size, text, z);
}
else
{
// raw data
src.Read(outbuf[c], 0, size);
}
}
// compose colors and store
int y_lim = y_blk + blockheight;
if (y_lim > height)
{
y_lim = height;
}
int outbuf_pos = 0;
for (int y = y_blk; y < y_lim; y++)
{
int current = y * stride;
int current_org = current;
if (prevline >= 0)
{
// not first line
switch (colors)
{
case 3:
TVPTLG5ComposeColors3To4(image_bits, current, prevline,
outbuf, outbuf_pos, width);
break;
case 4:
TVPTLG5ComposeColors4To4(image_bits, current, prevline,
outbuf, outbuf_pos, width);
break;
}
}
else
{
// first line
switch (colors)
{
case 3:
for (int pr = 0, pg = 0, pb = 0, x = 0;
x < width; x++)
{
int b = outbuf[0][outbuf_pos + x];
int g = outbuf[1][outbuf_pos + x];
int r = outbuf[2][outbuf_pos + x];
b += g; r += g;
image_bits[current++] = (byte)(pb += b);
image_bits[current++] = (byte)(pg += g);
image_bits[current++] = (byte)(pr += r);
image_bits[current++] = 0xff;
}
break;
case 4:
for (int pr = 0, pg = 0, pb = 0, pa = 0, x = 0;
x < width; x++)
{
int b = outbuf[0][outbuf_pos + x];
int g = outbuf[1][outbuf_pos + x];
int r = outbuf[2][outbuf_pos + x];
int a = outbuf[3][outbuf_pos + x];
b += g; r += g;
image_bits[current++] = (byte)(pb += b);
image_bits[current++] = (byte)(pg += g);
image_bits[current++] = (byte)(pr += r);
image_bits[current++] = (byte)(pa += a);
}
break;
}
}
outbuf_pos += width;
prevline = current_org;
}
}
PixelFormat format = 4 == colors ? PixelFormats.Bgra32 : PixelFormats.Bgr32;
return(ImageData.Create(info, format, null, image_bits, stride));
}
}
ImageData ReadV6(Stream stream, TlgMetaData info)
{
using (var src = new ArcView.Reader(stream))
{
int width = (int)info.Width;
int height = (int)info.Height;
int colors = info.BPP / 8;
int max_bit_length = src.ReadInt32();
int x_block_count = ((width - 1) / TVP_TLG6_W_BLOCK_SIZE) + 1;
int y_block_count = ((height - 1) / TVP_TLG6_H_BLOCK_SIZE) + 1;
int main_count = width / TVP_TLG6_W_BLOCK_SIZE;
int fraction = width - main_count * TVP_TLG6_W_BLOCK_SIZE;
var image_bits = new uint[height * width];
var bit_pool = new byte[max_bit_length / 8 + 5];
var pixelbuf = new uint[width * TVP_TLG6_H_BLOCK_SIZE + 1];
var filter_types = new byte[x_block_count * y_block_count];
var zeroline = new uint[width];
var LZSS_text = new byte[4096];
// initialize zero line (virtual y=-1 line)
uint zerocolor = 3 == colors ? 0xff000000 : 0x00000000;
for (var i = 0; i < width; ++i)
{
zeroline[i] = zerocolor;
}
uint[] prevline = zeroline;
int prevline_index = 0;
// initialize LZSS text (used by chroma filter type codes)
int p = 0;
for (uint i = 0; i < 32 * 0x01010101; i += 0x01010101)
{
for (uint j = 0; j < 16 * 0x01010101; j += 0x01010101)
{
LZSS_text[p++] = (byte)(i & 0xff);
LZSS_text[p++] = (byte)(i >> 8 & 0xff);
LZSS_text[p++] = (byte)(i >> 16 & 0xff);
LZSS_text[p++] = (byte)(i >> 24 & 0xff);
LZSS_text[p++] = (byte)(j & 0xff);
LZSS_text[p++] = (byte)(j >> 8 & 0xff);
LZSS_text[p++] = (byte)(j >> 16 & 0xff);
LZSS_text[p++] = (byte)(j >> 24 & 0xff);
}
}
// read chroma filter types.
// chroma filter types are compressed via LZSS as used by TLG5.
{
int inbuf_size = src.ReadInt32();
byte[] inbuf = src.ReadBytes(inbuf_size);
if (inbuf_size != inbuf.Length)
{
return(null);
}
TVPTLG5DecompressSlide(filter_types, inbuf, inbuf_size, LZSS_text, 0);
}
// for each horizontal block group ...
for (int y = 0; y < height; y += TVP_TLG6_H_BLOCK_SIZE)
{
int ylim = y + TVP_TLG6_H_BLOCK_SIZE;
if (ylim >= height)
{
ylim = height;
}
int pixel_count = (ylim - y) * width;
// decode values
for (int c = 0; c < colors; c++)
{
// read bit length
int bit_length = src.ReadInt32();
// get compress method
int method = (bit_length >> 30) & 3;
bit_length &= 0x3fffffff;
// compute byte length
int byte_length = bit_length / 8;
if (0 != (bit_length % 8))
{
byte_length++;
}
// read source from input
src.Read(bit_pool, 0, byte_length);
// decode values
// two most significant bits of bitlength are
// entropy coding method;
// 00 means Golomb method,
// 01 means Gamma method (not yet suppoted),
// 10 means modified LZSS method (not yet supported),
// 11 means raw (uncompressed) data (not yet supported).
switch (method)
{
case 0:
if (c == 0 && colors != 1)
{
TVPTLG6DecodeGolombValuesForFirst(pixelbuf, pixel_count, bit_pool);
}
else
{
TVPTLG6DecodeGolombValues(pixelbuf, c * 8, pixel_count, bit_pool);
}
break;
default:
throw new InvalidFormatException("Unsupported entropy coding method");
}
}
// for each line
int ft = (y / TVP_TLG6_H_BLOCK_SIZE) * x_block_count; // within filter_types
int skipbytes = (ylim - y) * TVP_TLG6_W_BLOCK_SIZE;
for (int yy = y; yy < ylim; yy++)
{
int curline = yy * width;
int dir = (yy & 1) ^ 1;
int oddskip = ((ylim - yy - 1) - (yy - y));
if (0 != main_count)
{
int start =
((width < TVP_TLG6_W_BLOCK_SIZE) ? width : TVP_TLG6_W_BLOCK_SIZE) *
(yy - y);
TVPTLG6DecodeLineGeneric(
prevline, prevline_index,
image_bits, curline,
width, 0, main_count,
filter_types, ft,
skipbytes,
pixelbuf, start,
zerocolor, oddskip, dir);
}
if (main_count != x_block_count)
{
int ww = fraction;
if (ww > TVP_TLG6_W_BLOCK_SIZE)
{
ww = TVP_TLG6_W_BLOCK_SIZE;
}
int start = ww * (yy - y);
TVPTLG6DecodeLineGeneric(
prevline, prevline_index,
image_bits, curline,
width, main_count, x_block_count,
filter_types, ft,
skipbytes,
pixelbuf, start,
zerocolor, oddskip, dir);
}
prevline = image_bits;
prevline_index = curline;
// Array.Copy (image_bits, curline, prevline, 0, width);
}
}
unsafe
{
fixed(void *data = image_bits)
{
int stride = width * 4;
PixelFormat format = 32 == info.BPP ? PixelFormats.Bgra32 : PixelFormats.Bgr32;
var bitmap = BitmapSource.Create(width, height, ImageData.DefaultDpiX, ImageData.DefaultDpiY,
format, null, (IntPtr)data, height * stride, stride);
bitmap.Freeze();
return(new ImageData(bitmap, info));
}
}
}
}
