TPortableNetworkGraphic class
Implements support for the PNG image format.
Declaration
TPortableNetworkGraphic = class(TFPImageBitmap)Inheritance
- TPortableNetworkGraphic
- TFPImageBitmap
- TCustomBitmap
- TRasterImage
- TGraphic
- TPersistent
- TObject
Description
TPortableNetworkGraphic is a
TFPImageBitmap descendant
which implements support for the
PNG (
Portable Network
Graphics) image format. PNG is a raster graphic file format that supports
loss-less data compression. PNG was developed as an improved, non-patented
replacement for GIF (Graphics Interchange Format).
PNG supports palette-based images (using 24-bit RGB or 32-bit RGBA colors), grayscale images (with or without alpha channel transparency), and full-color non-palette-based RGB or RGBA images. A PNG file contains a single image in an extensible chunk structure, and uses encoding to compress repetitive pixel values in the image.
PNG image files use the file extension PNG or png, and uses the MIME media type 'image/png'.
See also
Methods
GetReaderClass | protected | Gets the class reference used to create new instances of the FCL-compatible image reader. |
GetWriterClass | protected | Gets the class reference used to create new instances of the FCL-compatible image reader. |
InitializeWriter | protected | Configures the writer class instance for the image type. |
GetSharedImageClass | protected | Gets the class reference used to create new shared image instances in the class. |
IsStreamFormatSupported | public | Determines if the specified stream contains image data supported for the image type. |
GetFileExtensions | public | Returns a list of the file extensions available. |
Inherited
From TFPImageBitmap (8)
FinalizeReader FinalizeWriter GetMimeType InitializeReader IsFileExtensionSupported LazarusResourceTypeValid ReadStream WriteStream
From TCustomBitmap (35)
Assign BitmapHandleAllocated CanShareImage Changed Clear Create CreateDefaultBitmapHandle Destroy FreeImage FreeMaskHandle GetBitmapHandle GetMaskHandle GetPalette GetPixelFormat GetRawImageDescriptionPtr GetRawImagePtr Handle HandleNeeded HandleType InternalReleaseBitmapHandle InternalReleaseMaskHandle InternalReleasePalette MaskHandleAllocated MaskHandleNeeded Monochrome PaletteAllocated PaletteNeeded RawimageNeeded ReleaseHandle SetHandle SetHandles SetPixelFormat SetSize UnshareImage UpdateHandles
From TRasterImage (47)
ApplyTransparent BeginUpdate BitmapHandle BitmapHandleNeeded Canvas CreateIntfImage Draw EndUpdate FreeSaveStream GetEmpty GetHandle GetHeight GetMasked GetSize GetSupportedSourceMimeTypes GetTransparent GetWidth HandleAllocated LoadFromBitmapHandles LoadFromDevice LoadFromIntfImage LoadFromMimeStream LoadFromRawImage LoadFromStream Mask Masked MaskHandle PixelFormat RawImage ReadData ReleaseBitmapHandle ReleaseMaskHandle ReleasePalette RequestTransparentColor SaveStreamNeeded SaveToStream ScanLine SetBitmapHandle SetHeight SetMasked SetMaskHandle SetTransparent SetTransparentMode SetWidth TransparentColor TransparentMode WriteData
From TGraphic (25)
DefineProperties Empty Equals GetResourceType Height LoadFromClipboardFormat LoadFromClipboardFormatID LoadFromFile LoadFromLazarusResource LoadFromResourceID LoadFromResourceName MimeType Modified OnChange OnProgress Palette PaletteModified Progress SaveToClipboardFormat SaveToClipboardFormatID SaveToFile SetModified SetPalette Transparent Width
From TPersistent (6)
AssignTo FPOAttachObserver FPODetachObserver FPONotifyObservers GetNamePath GetOwner
From TObject (39)
AfterConstruction BeforeDestruction CheckDisposed ClassInfo ClassName ClassNameIs ClassParent ClassType CleanupInstance DefaultHandler DefaultHandlerStr Dispatch DispatchStr Disposed DisposeOf FieldAddress Free FreeInstance GetDisposed GetHashCode GetInterface GetInterfaceByStr GetInterfaceEntry GetInterfaceEntryByStr GetInterfaceTable GetInterfaceWeak GetLastCastErrorInfo InheritsFrom InitInstance InstanceSize MethodAddress MethodName newinstance QualifiedClassName SafeCallException StringMessageTable SystemHasExtendedRTTI ToString UnitName
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.