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Portable Network Graphics Formats (PNG and MNG)

LEADTOOLS reads and writes the following Portable Network Graphics formats:

PNG (Portable Network Graphics)

Is a replacement for the GIF format (single page). It is a full-featured (non-LZW) compressed format intended for widespread use without legal restraints.

LEADTOOLS supports reading and writing PNG 1+1 files.

LEADTOOLS supports reading (but not writing) interlaced PNG files. To implement the paint-while-load feature, set the LOADFILEOPTION. structure's Passes field to paint the image in more than one pass. Passes

You can read the following bits per pixel: 1, 4, 8, 16, 24, 32, 48, 64.

You can write the following bits per pixel: 1, 4, 8, 24, 32, 48, 64.

The file constant associated with this file format is:

Constant	Read Support (BPP)	Write Support (BPP)	Description
FILE_PNG	1, 4, 8, 16, 24, 32, 48, 64	1, 4, 8, 24, 32, 48, 64	[75] Portable Network Graphics (PNG).

MNG (Multiple-image Network Graphics)

Is a raster format was developed in PNG development group and supported by IrfanView, XnView, and ImageConverter. It is a member of the PNG (Portable Network Graphics) format family. It can contain animations, slide shows, complex still frames, comprised of multiple PNG or JNG single-image datastreams.

LEADTOOLS supports progressive reading and writing MNG files, multipage files (adding, replacing, inserting, and appending), and Lossless JPEG compression. The default extension is MNG.

LEAD supports version 1.0 of this format.

You can read the following bits per pixel: 24.

You can write the following bits per pixel: 1, 2, 4, 8, 16, 24, 32, 48, and 64.

It is possible to speed up the loading of large PNG and MNG files. For more information, refer to Using Filter Data to Speed up Loading Large Files.

For more information on the format, refer to http://www.libpng.org/pub/mng/spec/.

The file constants associated with these file formats are:

Constant	Read Support (BPP)	Write Support (BPP)	Description
FILE_MNG	24	1, 2, 4, 8, 24, 32, 48, 64	[327] Multiple-image Network Graphics (MNG).
FILE_MNG_GRAY	24	1, 2, 4, 8, 16	[329] Multiple-image Network Graphics (MNG) Grayscale.
FILE_MNG_JNG	24	8, 24	[330] Multiple-image Network Graphics (MNG) JNG format.
FILE_MNG_JNG_411	24	24	[331] Multiple-image Network Graphics (MNG) JNG format with JPEG 4:2:2 Compression.
FILE_MNG_JNG_422	24	24	[332] Multiple-image Network Graphics (MNG) JNG format with JPEG 4:1:1 Compression.

NOTE: MNG file format is based in part on libmng library. MNG file format is based in part on the work of the Independent JPEG Group.

Required DLLs and Libraries

LFPNG for PNG
LFMNG and LFCMP for MNG
For a listing of the exact DLLs needed, based on the toolkit version, refer to Files To Be Included With Your Application.