使用php从像素计算以英寸或dpi为单位的图像大小 [英] Calculating image size in inches or dpi from pixels using php

问题描述

我需要假设300dpi来计算以英寸为单位的近似图像大小。

I need to calculate an approximate image size in inches assuming 300dpi.

我有一个目标图像大小，我想向用户展示该图像他们已经上传了足够的图片，或者需要进行扩展，并根据此提供各种条件消息。

I have a target image size in mind, and i want to show the user if the image they have uploaded is adequate, or will need to be stretched, and offer various conditional messages based off of this.

我已经有像素的高度和宽度，只需要知道我猜的数学。

I already have the height and width in pixels, just need to know the math i guess.

推荐答案

DPI =每英寸点数。一个点=一个像素。

DPI = "dots per inch". One dot = one pixel.

300 dpi（300 dpi）：1英寸。您可以解决：-）

300 pixels in 300 dpi: 1 inch. You can work it out :-)

这篇关于使用php从像素计算以英寸或dpi为单位的图像大小的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！