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TJPEGImage - a class for handling images stored in JPEG (compressed) format
Source position: graphics.pp line 1628
type TJPEGImage = class(TFPImageBitmap) |
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protected |
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procedure InitializeReader(); override; |
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procedure InitializeWriter(); override; |
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procedure FinalizeReader(); override; |
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function GetReaderClass; override; |
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function GetWriterClass; override; |
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function GetSharedImageClass; override; |
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public |
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constructor Create; override; |
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function GetFileExtensions; override; |
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property CompressionQuality: TJPEGQualityRange; [rw] |
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Determine the compression quality for this image |
property GrayScale: Boolean; [r] |
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Is this a grayscale image? |
property ProgressiveEncoding: Boolean; [r] |
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Is progressive encoding used for this JPEG? |
property Performance: TJPEGPerformance; [rw] |
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Set for best quality or best speed |
end; |
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TJPEGImage - a class for handling images stored in JPEG (compressed) format |
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A class of Bitmap using the FPImage reader and writer (ie customised for FreePascal) |
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TCustomBitMap - the base class for TBitmap |
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TRasterImage - base class for a number of graphic controls, including TCustomBitmap and TCustomIcon, which use a raster of dots to display graphic information |
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Base class for dealing with Graphic images |
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TObject |
JPEG images are very commonly used for storing digital photographs. They can represent detailed colour photos using a high degree of compression, resulting in very efficient storage, though with some loss of quality.
The properties CompressionQuality (an integer between 1 and 100, with 100 representing the best quality) and Performance (an enumerated variable with two states: BestQuality or BestSpeed ie compression) can be used to determine the balance between efficiency of storage and quality of picture.
lazarus-ccr.sourceforge.net |