如何生成特定现实世界大小的映像

Question

我需要生成的图像上，将线表示吉他上的烦恼之间的距离。它应该在以后印刷，并作为标记烦恼的面具。因此，距离必须精确

如何生成特定大小的图像（以厘米/毫米为单位），以便在打印时具有相同的大小

我可以使用Python／JS/java／C++ +<

Answer 1

正如@Chris G在评论中写道的：

Generating an image is pixel based. If you create an image that has a line every 300 pixels and print it at 300dpi, the lines will be exactly one inch apart. (dpi = dots per inch). You can set the dpi in Photoshop for instance, then make sure the image is printed @ 100% scaling. (in case it's not clear: the "digital distance" doesn't matter, since you can always adjust the dpi to achieve a specific millimeter distance in the printout)

例如，如果我制作一个大小为6*300px和9*300px的图像，并用300dpi打印，它在纸上的尺寸将是6x9英寸