Tim Roberts wrote: > "Lad" <[EMAIL PROTECTED]> wrote: > > >from > >> image: > >> http://www.pythonware.com/library/pil/handbook/image.htm > >> > >> This is some example code: > >> > >> from PIL import Image > >> im = Image.open("1.jpg") > >> nx, ny = im.size > >> im2 = im.resize((int(nx*1.5), int(ny*1.5)), Image.BICUBIC) > >> im2.save("2.png") > >> > >> Bye, > > bearophile, > >Thank you for your reply. > >But the above code increases size only , but not DPI resolutions( > >vertical nad horizontal).I need a higher vertical and horisontal > >resolutions. > > I'm not convinced that you know what you are asking for. > > Let's say you have an image that is 300x300 pixels, that is tagged as being > 100 dpi. Such an image is expected to be printed at a 3" x 3" size. > > Now, if you want to increase the dpi to 300 dpi, what does that mean? Does > it mean you want that same picture to be printed at a 1" x 1" size? If so, > then all you need to change is the picture header. It will still be > 300x300 pixels, and the file will be the same number of bytes. > > Or, do you mean that you want the picture to continue to print as 3" x 3", > but to have three times as many pixels in each direction? That means you > have to increase the number of pixels to 900x900. That's exactly what the > code above is doing. The image file will be 9 times larger.
Tim , Thank you for the explanation, And I must also thank you all you others, who helped me. Particularly, bearophile and Max. Now I use the following code , that provided bearophile, from PIL import Image im = Image.open("output3.jpg") nx, ny = im.size im2 = im.resize((int(nx*2.5), int(ny*2.5)), Image.BICUBIC) im2.save("2000.png",dpi=(520,520)) and very important thing was dpi=(520,520) that provided Max, L. -- http://mail.python.org/mailman/listinfo/python-list