JpegTransforms
Ecng.Drawing
The arithmetic both JPEG decoders share: the inverse DCT and the conversion of decoded components to RGBA.
Propiedades
ZigZag
public static ReadOnlySpan<byte> ZigZag { get; }value = JpegTransforms.ZigZagPosition in a block of each coefficient, in the zigzag order coefficients are coded in.
Métodos
InverseDct
public static void InverseDct(ReadOnlySpan<int> block, byte[] samples, int stride, int left, int top)JpegTransforms.InverseDct(block, samples, stride, left, top)Turns the dequantized coefficients of one block into 8x8 samples.
- block
- 64 coefficients in natural order.
- samples
- The plane the samples go to.
- stride
- Length of a row of the plane.
- left
- Column of the block in the plane.
- top
- Row of the block in the plane.
ResolveColorModel
public static JpegColorModels ResolveColorModel(JpegComponent[] components, bool hasJfif, int adobeTransform)result = JpegTransforms.ResolveColorModel(components, hasJfif, adobeTransform)Decides what the components of a frame stand for, the way libjpeg does.
- components
- The components of the frame.
- hasJfif
- Whether the file has a JFIF segment.
- adobeTransform
- The transform flag of the Adobe segment, or -1 if the file has none.
ToImage
public static RasterImage ToImage(int width, int height, JpegComponent[] components, JpegColorModels model)result = JpegTransforms.ToImage(width, height, components, model)Builds the picture out of the decoded sample planes.