ImageExtensionsSaveAsPng(Image, Stream) Method

public static void SaveAsPng(
	this Image image,
	Stream stream
)

<ExtensionAttribute>
Public Shared Sub SaveAsPng ( 
	image As Image,
	stream As Stream
)

public:
[ExtensionAttribute]
static void SaveAsPng(
	Image^ image, 
	Stream^ stream
)

[<ExtensionAttribute>]
static member SaveAsPng : 
        image : Image * 
        stream : Stream -> unit 

Parameters

image  Image

The image to save. If contains multiple images, then only the current frame will be saved.

stream  Stream

The stream to save the image into.

Usage Note

The image can only be saved if a built-in PNG encoder is available in the current operating system.

The saved PNG image will have 32 BPP format if the source image can have transparency; otherwise, it will have 24 BPP format.

On Windows PNG is never saved with indexed format.

Images with different PixelFormats are handled as follows (on Windows, unless specified otherwise):

Format1bppIndexed

On Windows, when reloading the saved image the pixel format will turn Format32bppArgb. On Linux, when reloading the saved image the pixel format is preserved, though transparency will be lost.

Format4bppIndexed

On Windows, when reloading the saved image the pixel format will turn Format32bppArgb. On Linux, when reloading the saved image the pixel format is preserved, though transparency will be lost.

Format8bppIndexed

On Windows, when reloading the saved image the pixel format will turn Format32bppArgb. On Linux, when reloading the saved image the pixel format is preserved, though transparency will be lost.

Format16bppGrayScale

Before saving the image pixel format will be converted to Format24bppRgb because otherwise GDI+ would throw an exception.

Format16bppRgb555

Before saving the image pixel format will be converted to Format24bppRgb because the built-in encoder would save a 32 BPP image otherwise, which is just a waste of space.

Format16bppRgb565

Before saving the image pixel format will be converted to Format24bppRgb because the built-in encoder would save a 32 BPP image otherwise, which is just a waste of space.

Format16bppArgb1555

When reloading the saved image the pixel format will turn Format32bppArgb.

Format24bppRgb

When reloading the saved image the pixel format is preserved.

Format32bppRgb

When reloading the saved image the pixel format will turn Format32bppArgb.

Format32bppArgb

When reloading the saved image the pixel format is preserved.

Format32bppPArgb

On Windows, when reloading the saved image the pixel format will turn Format32bppArgb. On Linux, before saving the image pixel format will be converted to Format32bppArgb; otherwise, the alpha channel in the saved image would be corrupted.

Format48bppRgb

Before saving the image pixel format will be converted to Format24bppRgb because the built-in encoder would save a 32 BPP image with incorrect colors otherwise.

Format64bppArgb

Before saving the image pixel format will be converted to Format32bppArgb because the built-in encoder would save the image incorrectly otherwise.

Format64bppPArgb

Before saving the image pixel format will be converted to Format32bppArgb because the built-in encoder would save the image incorrectly otherwise.

Reference