So, if I have an image that is rotated, scaled, skewed, how could I get the matrix decomposed?
If my matrix contains all the possible transformation, have I to decompose the matrix (obtaining some intermediate matrix subtracting something) or could I find my values (rotating degrees, scaling factor, etc….) in another manner?
Below there is written “if the image is rotated” and then I find the scaling value. What could I do with it?
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A:
thank you for the explanation, it’s been very useful for me.
Only a question.
We usually work with PDF files without visualizing them in a pdfviewer. So I think the “visual factor” could be excluded.
Given a Matrix2D on an image, could I understand if it contains a translation, a rotation, a scaling or a shear matrix only looking at it?
Because if I want the image as its original state (before being included in a PDF…) I have to understand its data.
So I should understand if looking at a given matrix I can find out if the image is rotated, is scaled, only looking at it. Is it correct?
If the image is only translated, it’s simple, also if it’s only rotated. But if the image is either rotated, scaled, translated, could I understand it in order to extract the image and compare it with the one included in the pdf?