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resolutionimageresizer

Image re sizing

I have an image which 330 px width and 472 px height . I want to plot this image inn to a bigger canvas which is 55% bigger than the current picture .. How can I fount the final image width and height .

Solution

  • This is more of a math problem than a programming problem. Let's work on it abstractly to get a formula:

    Our variables are:

    oldWidth, oldHeight, newWidth, newHeight, percentBigger

    The original canvas size is

    oldCanvasSize = oldWidth * oldHeight

    The new canvas size is

    newCanvasSize = newWidth + newHeight

    55% bigger means 155% or 1.55 so

    percent = (percentBigger + 1)

    The new canvas is some percent of the old canvas so we have

    newCanvasSize = percent * oldCanvasSize

    or

    newCanvasSize = (percentBigger + 1) * oldCanvasSize

    I'll assume we want the proportions to stay the same so

    oldWidth / oldHeight = newWidth / newHeight

    By substitution and solving the above equations we get

    newWidth = SquareRoot(percentBigger + 1) * oldWidth

    newHeight = SquareRoot(percentBigger + 1) * oldHeight

    I'll let the reader plug in the values.