/// <summary> Create Color[] from PNG file, async </summary>
public static async Task <ReadColorsResult> ReadColorsAsync
(
string filePath
)
{
ReadColorsResult results = new ReadColorsResult {
pixels = null,
width = -1,
height = -1,
textureFormatInfered = 0
};
PngReader reader = null;
try
{
reader = FileHelper.CreatePngReader(filePath);
var info = reader.ImgInfo;
results.height = info.Rows;
results.width = info.Cols;
results.pixels = new Color[results.width * results.height];
int channels = info.Channels;
int bitDepth = info.BitDepth;
//select appropriate texture format:
results.textureFormatInfered = GetTextureFormat(bitDepth, channels, info.Indexed);
//create pixel array:
await Task.Run(() => {
ReadSamples(reader, results);
});
}
catch (System.Exception ex)
{
Debug.LogException(ex);
if (results.pixels == null)
{
results.width = 2;
results.height = 2;
results.pixels = new Color[results.width * results.height];
}
if (results.textureFormatInfered == 0)
{
results.textureFormatInfered = TextureFormat.RGBA32;
}
}
finally
{
if (reader != null)
{
reader.Dispose();
}
}
return(results);
}
/// <summary> Create Color[] from PNG file </summary>
public static ReadColorsResult ReadColors
(
string filePath
)
{
ReadColorsResult results = new ReadColorsResult {
pixels = null,
width = -1,
height = -1,
textureFormatInfered = 0
};
PngReader reader = null;
try
{
reader = FileHelper.CreatePngReader(filePath);
var info = reader.ImgInfo;
results.height = info.Rows;
results.width = info.Cols;
results.pixels = new Color[results.width * results.height];
int channels = info.Channels;
int bitDepth = info.BitDepth;
if (info.Indexed)
{
throw new System.NotImplementedException("indexed png not implemented");
}
//select appropriate texture format:
results.textureFormatInfered = GetTextureFormat(bitDepth, channels);
//create pixel array:
for (int row = 0; row < results.height; row++)
{
ImageLine imageLine = reader.ReadRowInt(row);
var scanline = imageLine.Scanline;
if (imageLine.SampleType == ImageLine.ESampleType.INT)
{
for (int col = 0; col < results.width; col++)
{
var color = new Color();
for (int ch = 0; ch < channels; ch++)
{
int raw = scanline[col * channels + ch];
float rawMax = GetBitDepthMaxValue(bitDepth);
float value = (float)raw / rawMax;
//
if (ch == 0)
{
color.r = value;
}
else if (ch == 1)
{
color.g = value;
}
else if (ch == 2)
{
color.b = value;
}
else if (ch == 3)
{
color.a = value;
}
else
{
throw new System.Exception($"channel { ch } not implemented");
}
}
results.pixels[IndexPngToTexture(row, col, results.height, results.width)] = color;
}
}
else
{
throw new System.Exception($"imageLine.SampleType { imageLine.SampleType } not implemented");
}
}
}
catch (System.Exception ex)
{
Debug.LogException(ex);
if (results.pixels == null)
{
results.width = 2;
results.height = 2;
results.pixels = new Color[results.width * results.height];
}
if (results.textureFormatInfered == 0)
{
results.textureFormatInfered = TextureFormat.RGBA32;
}
}
finally
{
if (reader != null)
{
reader.End();
}
}
return(results);
}
/// <summary> Reads samples using given reader </summary>
static void ReadSamples(PngReader reader, ReadColorsResult results)
{
var info = reader.ImgInfo;
int channels = info.Channels;
int bitDepth = info.BitDepth;
int numCols = results.width;
int numRows = results.height;
Color[] pixels = results.pixels;
float max = GetBitDepthMaxValue(bitDepth);
if (!info.Indexed)
{
if (!info.Packed)
{
for (int row = 0; row < numRows; row++)
{
ImageLine imageLine = reader.ReadRow(row);
ProcessNByteRow(imageLine, pixels);
}
}
else
{
if (bitDepth == 4)
{
for (int row = 0; row < numRows; row++)
{
ImageLine imageLine = reader.ReadRowByte(row);
Process4BitRow(imageLine, pixels);
}
}
else if (bitDepth == 2)
{
throw new System.Exception($"bit depth {bitDepth} for {channels} channels not implemented\n");
}
else if (bitDepth == 1)
{
for (int row = 0; row < numRows; row++)
{
ImageLine imageLine = reader.ReadRowByte(row);
Process1BitRow(imageLine, pixels);
}
}
else
{
throw new System.Exception($"bit depth {bitDepth} for {channels} channels not implemented\n");
}
}
}
else
{
var plte = reader.GetMetadata().GetPLTE();
if (bitDepth == 8)
{
if (info.Alpha)
{
var trns = reader.GetMetadata().GetTRNS(); // transparency metadata, can be null
for (int row = 0; row < numRows; row++)
{
ImageLine imageLine = reader.ReadRow(row);
Process8BitIndexedRow(imageLine, plte, trns, pixels);
}
}
else
{
for (int row = 0; row < numRows; row++)
{
ImageLine imageLine = reader.ReadRow(row);
Process8BitIndexedRow(imageLine, plte, pixels);
}
}
}
else if (bitDepth == 4)
{
for (int row = 0; row < numRows; row++)
{
ImageLine imageLine = reader.ReadRow(row);
Process4BitIndexedRow(imageLine, plte, pixels);
}
}
else
{
throw new System.Exception($"bit depth {bitDepth} for {channels} channels not implemented\n");
}
}
}
