通过像素数量调整图像大小 [英] Resize image by pixel amount

问题描述

我试图找到答案，但我不能。

I tried to find out, but I couldn't.

有一个形象，例如， 241x76 共拥有的18316像素（241 * 76）。 调整大小规则，像素数无法通过 10,000 。 然后，我怎么能得到新的大小保持纵横比和获得小于 10,000 像素？

A image, for example, 241x76 has a total of 18,316 pixels (241 * 76). The resize rule is, the amount of pixels cannot pass 10,000. Then, how can I get the new size keeping the aspect ratio and getting less than 10,000 pixels?

推荐答案

伪code：

pixels = width * height
if (pixels > 10000) then
  ratio = width / height
  scale = sqrt(pixels / 10000)
  height2 = floor(height / scale)
  width2 = floor(ratio * height / scale)
  ASSERT width2 * height2 <= 10000
end if

记住使用浮点运算涉及比和比例实施的时候。

的Python

import math

def capDimensions(width, height, maxPixels=10000):
  pixels = width * height
  if (pixels <= maxPixels):
    return (width, height)

  ratio = float(width) / height
  scale = math.sqrt(float(pixels) / maxPixels)
  height2 = int(float(height) / scale)
  width2 = int(ratio * height / scale)
  return (width2, height2)

这篇关于通过像素数量调整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！