c++ - GDI+ : Changing DPI -


i have 2 points need clarifief on :

  • changing image dpi 200 100 mean have resize image half or keep actual dimensions decrease dpi.

  • i herd gdi+ nice alternative change image dpi, googled in way found no example showing how change dpi gdi+.

any idea questions, , thank you.

changing dpi of existing image doesn't make sense. records resolution of device created image. can displayed @ same physical size on device different dpi setting. how image drew in painting program on monitor 96 dpi doesn't turn postage stamp one-sixth size when print on printer 600 dpi resolution.

by changing in code when have image, trying change characteristics of device created image. doesn't make sense, code cannot reach and, say, change ccd in camera or change monitor resolution.

it's reference number.

you can display or print image @ size want, doesn't have match original size.


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