Rmagickeach_pixel，它是如何工作的？

发布于 2025-01-01 00:32:00 字数 340 浏览 3 评论 0原文

我需要在 rmagick 中操作图像的每个像素。我正在 IRB（交互式红宝石）中执行此操作，这就是我所拥有的：

require 'Rmagick'
include Magick
f = Image.new(100,100)
f.display #so far so good. A 100x100 white image is displayed

f.each_pixel {|pixel, c, r| pixel.red = 0}
f.display #the image is still white. It should really be a shade of blue.

我做错了什么？

原文

I need to manipulate each pixel of an image in rmagick. I am doing this in IRB(interactive ruby) This is what I have:

require 'Rmagick'
include Magick
f = Image.new(100,100)
f.display #so far so good. A 100x100 white image is displayed

f.each_pixel {|pixel, c, r| pixel.red = 0}
f.display #the image is still white. It should really be a shade of blue.

What am I doing wrong?

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

拥抱没勇气 2025-01-08 00:32:00

问题是，从each_pixel 返回的数组是一个新的数据集。数据需要存储回图像。

使用 get_pixels 和 store_pixels 代替：

img = Magick::ImageList.new('img.jpg').first
pixels = img.get_pixels(0,0,img.columns,img.rows)

for pixel in pixels
    avg = (pixel.red + pixel.green + pixel.blue) / 3
    pixel.red = avg
    pixel.blue = avg
    pixel.green = avg
end

img.store_pixels(0,0, img.columns, img.rows, pixels)
img.display

The thing is, the array you get back from each_pixel is a new dataset. The data needs to be stored back to the image.

Use get_pixels and store_pixels instead:

img = Magick::ImageList.new('img.jpg').first
pixels = img.get_pixels(0,0,img.columns,img.rows)

for pixel in pixels
    avg = (pixel.red + pixel.green + pixel.blue) / 3
    pixel.red = avg
    pixel.blue = avg
    pixel.green = avg
end

img.store_pixels(0,0, img.columns, img.rows, pixels)
img.display

回复收藏 0 原文

~没有更多了~