/// <summary>
/// Encodes the specified image data to png.
/// </summary>
/// <param name="pixels">
/// The pixel data (bottom line first).
/// </param>
/// <param name="dpi">
/// The image resolution in dots per inch.
/// </param>
/// <returns>
/// The png image data.
/// </returns>
public static byte[] Encode(OxyColor[,] pixels, int dpi = 96)
{
int height = pixels.GetLength(0);
int width = pixels.GetLength(1);
var bytes = new byte[(width * height * 4) + height];
int k = 0;
for (int i = height - 1; i >= 0; i--)
{
bytes[k++] = 0; // Filter
for (int j = 0; j < width; j++)
{
bytes[k++] = pixels[i, j].R;
bytes[k++] = pixels[i, j].G;
bytes[k++] = pixels[i, j].B;
bytes[k++] = pixels[i, j].A;
}
}
var w = new MemoryWriter();
w.Write((byte)0x89);
w.Write("PNG\r\n\x1a\n".ToCharArray());
WriteChunk(w, "IHDR", CreateHeaderData(width, height));
WriteChunk(w, "pHYs", CreatePhysicalDimensionsData(dpi, dpi));
WriteChunk(w, "IDAT", CreateUncompressedBlocks(bytes));
WriteChunk(w, "IEND", new byte[0]);
return(w.ToArray());
}
/// <summary>
/// Encodes the specified image data to png.
/// </summary>
/// <param name="pixels">The pixel data indexed as [x,y] (bottom line first).</param>
/// <returns>The png image data.</returns>
public byte[] Encode(OxyColor[,] pixels)
{
int width = pixels.GetLength(0);
int height = pixels.GetLength(1);
var bytes = new byte[(width * height * 4) + height];
int k = 0;
for (int y = 0; y < height; y++)
{
bytes[k++] = 0; // Filter
for (int x = 0; x < width; x++)
{
bytes[k++] = pixels[x, y].R;
bytes[k++] = pixels[x, y].G;
bytes[k++] = pixels[x, y].B;
bytes[k++] = pixels[x, y].A;
}
}
var w = new MemoryWriter();
w.Write((byte)0x89);
w.Write("PNG\r\n\x1a\n".ToCharArray());
WriteChunk(w, "IHDR", CreateHeaderData(width, height));
WriteChunk(w, "pHYs", CreatePhysicalDimensionsData(this.options.DpiX, this.options.DpiY));
WriteChunk(w, "IDAT", CreateUncompressedBlocks(bytes));
WriteChunk(w, "IEND", new byte[0]);
return(w.ToArray());
}
/// <summary>
/// Creates the uncompressed blocks.
/// </summary>
/// <param name="bytes">
/// The data.
/// </param>
/// <returns>
/// The output data.
/// </returns>
private static byte[] CreateUncompressedBlocks(byte[] bytes)
{
// http://www.w3.org/TR/PNG-Compression.html
const int MaxDeflate = 0xFFFF;
var w = new MemoryWriter();
const uint CompressionMethod = 8;
const uint Check = (31 - ((CompressionMethod << 8) % 31)) % 31;
w.Write((byte)CompressionMethod);
w.Write((byte)Check);
for (int i = 0; i < bytes.Length; i += MaxDeflate)
{
var n = (ushort)Math.Min(bytes.Length - i, MaxDeflate);
var last = (byte)(i + n < bytes.Length ? 0 : 1);
w.Write(last);
w.Write((byte)(n & 0xFF));
w.Write((byte)((n >> 8) & 0xFF));
var n2 = ~n;
w.Write((byte)(n2 & 0xFF));
w.Write((byte)((n2 >> 8) & 0xFF));
w.Write(bytes, i, n);
}
WriteBigEndian(w, Adler32(bytes));
return(w.ToArray());
}
/// <summary>
/// Creates the physical dimensions data.
/// </summary>
/// <param name="dpix">
/// The horizontal resolution.
/// </param>
/// <param name="dpiy">
/// The vertical resolution.
/// </param>
/// <returns>
/// The data.
/// </returns>
private static byte[] CreatePhysicalDimensionsData(int dpix, int dpiy)
{
var ppux = (int)(dpix / 0.0254);
var ppuy = (int)(dpiy / 0.0254);
var w = new MemoryWriter();
WriteBigEndian(w, ppux);
WriteBigEndian(w, ppuy);
w.Write((byte)1); // Unit: metre
return(w.ToArray());
}
/// <summary>
/// Creates the header data.
/// </summary>
/// <param name="width">
/// The width.
/// </param>
/// <param name="height">
/// The height.
/// </param>
/// <returns>
/// The header.
/// </returns>
private static byte[] CreateHeaderData(int width, int height)
{
// http://www.w3.org/TR/PNG-Chunks.html
var w = new MemoryWriter();
WriteBigEndian(w, width);
WriteBigEndian(w, height);
w.Write((byte)8); // bit depth
w.Write((byte)6); // color type RGBA
w.Write((byte)0); // compression method
w.Write((byte)0); // filter method
w.Write((byte)0); // interlace method
return(w.ToArray());
}
/// <summary>
/// Encodes the specified image data to png.
/// </summary>
/// <param name="pixels">
/// The pixel data (bottom line first).
/// </param>
/// <param name="dpi">
/// The image resolution in dots per inch.
/// </param>
/// <returns>
/// The png image data.
/// </returns>
public static byte[] Encode(OxyColor[,] pixels, int dpi = 96)
{
int height = pixels.GetLength(0);
int width = pixels.GetLength(1);
var bytes = new byte[(width * height * 4) + height];
int k = 0;
for (int i = height - 1; i >= 0; i--)
{
bytes[k++] = 0; // Filter
for (int j = 0; j < width; j++)
{
bytes[k++] = pixels[i, j].R;
bytes[k++] = pixels[i, j].G;
bytes[k++] = pixels[i, j].B;
bytes[k++] = pixels[i, j].A;
}
}
var w = new MemoryWriter();
w.Write((byte)0x89);
w.Write("PNG\r\n\x1a\n".ToCharArray());
WriteChunk(w, "IHDR", CreateHeaderData(width, height));
WriteChunk(w, "pHYs", CreatePhysicalDimensionsData(dpi, dpi));
WriteChunk(w, "IDAT", CreateUncompressedBlocks(bytes));
WriteChunk(w, "IEND", new byte[0]);
return w.ToArray();
}
/// <summary>
/// Creates the uncompressed blocks.
/// </summary>
/// <param name="bytes">
/// The data.
/// </param>
/// <returns>
/// The output data.
/// </returns>
private static byte[] CreateUncompressedBlocks(byte[] bytes)
{
// http://www.w3.org/TR/PNG-Compression.html
const int MaxDeflate = 0xFFFF;
var w = new MemoryWriter();
const uint CompressionMethod = 8;
const uint Check = (31 - ((CompressionMethod << 8) % 31)) % 31;
w.Write((byte)CompressionMethod);
w.Write((byte)Check);
for (int i = 0; i < bytes.Length; i += MaxDeflate)
{
var n = (ushort)Math.Min(bytes.Length - i, MaxDeflate);
var last = (byte)(i + n < bytes.Length ? 0 : 1);
w.Write(last);
w.Write((byte)(n & 0xFF));
w.Write((byte)((n >> 8) & 0xFF));
var n2 = ~n;
w.Write((byte)(n2 & 0xFF));
w.Write((byte)((n2 >> 8) & 0xFF));
w.Write(bytes, i, n);
}
WriteBigEndian(w, Adler32(bytes));
return w.ToArray();
}
/// <summary>
/// Creates the physical dimensions data.
/// </summary>
/// <param name="dpix">
/// The horizontal resolution.
/// </param>
/// <param name="dpiy">
/// The vertical resolution.
/// </param>
/// <returns>
/// The data.
/// </returns>
private static byte[] CreatePhysicalDimensionsData(int dpix, int dpiy)
{
var ppux = (int)(dpix / 0.0254);
var ppuy = (int)(dpiy / 0.0254);
var w = new MemoryWriter();
WriteBigEndian(w, ppux);
WriteBigEndian(w, ppuy);
w.Write((byte)1); // Unit: metre
return w.ToArray();
}
/// <summary>
/// Creates the header data.
/// </summary>
/// <param name="width">
/// The width.
/// </param>
/// <param name="height">
/// The height.
/// </param>
/// <returns>
/// The header.
/// </returns>
private static byte[] CreateHeaderData(int width, int height)
{
// http://www.w3.org/TR/PNG-Chunks.html
var w = new MemoryWriter();
WriteBigEndian(w, width);
WriteBigEndian(w, height);
w.Write((byte)8); // bit depth
w.Write((byte)6); // color type RGBA
w.Write((byte)0); // compression method
w.Write((byte)0); // filter method
w.Write((byte)0); // interlace method
return w.ToArray();
}
/// <summary>
/// Encodes the specified image data to png.
/// </summary>
/// <param name="pixels">The pixel data indexed as [x,y] (bottom line first).</param>
/// <returns>The png image data.</returns>
public byte[] Encode(OxyColor[,] pixels)
{
int width = pixels.GetLength(0);
int height = pixels.GetLength(1);
var bytes = new byte[(width * height * 4) + height];
int k = 0;
for (int y = 0; y < height; y++)
{
bytes[k++] = 0; // Filter
for (int x = 0; x < width; x++)
{
bytes[k++] = pixels[x, y].R;
bytes[k++] = pixels[x, y].G;
bytes[k++] = pixels[x, y].B;
bytes[k++] = pixels[x, y].A;
}
}
var w = new MemoryWriter();
w.Write((byte)0x89);
w.Write("PNG\r\n\x1a\n".ToCharArray());
WriteChunk(w, "IHDR", CreateHeaderData(width, height));
WriteChunk(w, "pHYs", CreatePhysicalDimensionsData(this.options.DpiX, this.options.DpiY));
WriteChunk(w, "IDAT", CreateUncompressedBlocks(bytes));
WriteChunk(w, "IEND", new byte[0]);
return w.ToArray();
}
