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Scale an image to certain dimension

Posted: Thu Feb 23, 2012 1:52 pm
by mmasroorali
Dear All,
I can do this by trial and error. But I was wondering whether I can do this precisely using some automatic technique.

I have imported an image (say png) inside qcad. I know that a certain edge in the image in 100 meters in actual dimension. What will be the best way to scale the image so that that particular edge becomes 100 meters inside qcad.

At this moment, all I can do is try one scaling factor and then go through trial and error.

Any tips will be appreciated.

Posted: Thu Feb 23, 2012 3:28 pm
by andrew
- Insert the bitmap
- Use tool 'Info' - 'Distance Point to Point' to measure the length of the edge that has to be 100m. The result is printed in the QCAD command line history, for example '176'.
- Scale image by factor f = (desired value) / (measured value). For example f = 100 / 176 = 0.568181818.

Posted: Thu Feb 23, 2012 3:40 pm
by mmasroorali
Thanks a lot. It worked, perfectly.