c# When does System.Drawing.Bitmap decompress the image stream? -

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right using system.drawing.bitmap take image , divide regions. assume bitmap must decompress image in order perform operations on it.

however, bitmap class accepts these formats: bmp, gif, exif, jpg, png , tiff

some of these formats compressed, if data in stream compressed, doesn't have decompressed perform manipulations? if so, mean bitmap class allocates more memory decompressed version of stream?

i feel if bitmap class makes data modifications stream have decompress stream should make bitmap class take same amount of memory working bmp streams when works png streams, despite fact png streams smaller.

in fact does, gdi needs raw pixel data feed graphic card and/or represent it, yes, it's being decompressed, may don't see memory rising because it's done system/graphic card.

some special cases dxt textures , other special types understood hardware , don't need decompressed work.


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