ImageMagick

Crop image in R

江枫思渺然 提交于 2021-01-28 05:10:53
问题 I am trying to crop an image using the magick package in R. My goal is to crop the upper left corner portion of the image. So far my code seems to work for some images but the same dimensions do not work for other images.This is my code: library(magick) library(tidyverse) image_read("http://www.gettyimages.com/gi-resources/images/Plugins/Chrometab.jpg")%>% image_chop("0x185+190")%>%image_crop("50x55+1") I am doing this for several images all of which have the dimensions width 320 height 240.

How to crop the difference of two images?

拟墨画扇 提交于 2021-01-27 14:10:37
问题 I'd like to take these 2 images: And essentially produce this: I've gotten as far as using compare with fuzz to define the part that has changed. Is it possible to then get the bounding box of this area and crop the second frame? 回答1: I would do something along these lines: convert a.jpg b.jpg -colorspace gray -blur 0x2 \ -compose difference -composite \ -threshold 20% out.jpg Convert to greyscale and blur a little to hide small differences, then calculate the difference and threshold to make

Converting a PDF to JPG with ImageMagick in PHP Gives Odd Letter Spacing

佐手、 提交于 2021-01-27 07:28:13
问题 I am trying to convert a PDF to a JPG with a PHP exec() call, which looks like this: convert page.pdf -resize 716x716 page.jpg For some reason, the JPG comes out with janky text, despite the PDF looking just fine in Acrobat and Mac Preview. Here is the original PDF: http://whit.info/dev/conversion/page.pdf and here is the janktastic output: http://whit.info/dev/conversion/page.jpg The server is a LAMP stack with PHP 5 and ImageMagick 6.2.8. Can you help this stumped Geek? Thanks in advance,

Converting a PDF to JPG with ImageMagick in PHP Gives Odd Letter Spacing

假如想象 提交于 2021-01-27 07:27:08
问题 I am trying to convert a PDF to a JPG with a PHP exec() call, which looks like this: convert page.pdf -resize 716x716 page.jpg For some reason, the JPG comes out with janky text, despite the PDF looking just fine in Acrobat and Mac Preview. Here is the original PDF: http://whit.info/dev/conversion/page.pdf and here is the janktastic output: http://whit.info/dev/conversion/page.jpg The server is a LAMP stack with PHP 5 and ImageMagick 6.2.8. Can you help this stumped Geek? Thanks in advance,

Converting a PDF to JPG with ImageMagick in PHP Gives Odd Letter Spacing

一曲冷凌霜 提交于 2021-01-27 07:27:03
问题 I am trying to convert a PDF to a JPG with a PHP exec() call, which looks like this: convert page.pdf -resize 716x716 page.jpg For some reason, the JPG comes out with janky text, despite the PDF looking just fine in Acrobat and Mac Preview. Here is the original PDF: http://whit.info/dev/conversion/page.pdf and here is the janktastic output: http://whit.info/dev/conversion/page.jpg The server is a LAMP stack with PHP 5 and ImageMagick 6.2.8. Can you help this stumped Geek? Thanks in advance,

开源OA办公平台搭建教程:在O2OA中使用网络会议(一)

天涯浪子 提交于 2021-01-14 16:27:20
本文主要讲解Openmeetings-5.1.0安装的过程,O2OA服务器的相关配置教程将随后发布。 教程比较详细,可以按照步骤一步一步安装服务器的安装,如果您在安装过程中有遇到其他的问题,请及时联系我们,我们会进一步更新安装手册。 O2OA实际上是集成Openmeeting来实现网络会议的,Apache-Openmeeting是一个开源的网络会议系统,我们可以在Openmeeting官方网站上得到更多的信息。 介于Openmeetings的安装比较复杂,所以在这里,我们也把我们安装的过程共享出来,希望对大家有所帮助: Openmeetings官网: https://openmeetings.apache.org/ Openmeetings官网下载: https://openmeetings.apache.org/downl Openmeetings官方手册: https://openmeetings.apache.org/installation.html 从 Openmeeting官方发布的安装手册中可以看到,服务器的安装需要如下几个步骤: 本文后续就按照Openmeeting官方安装手册的要求逐步完成目前最新版本5.1.0的安装: Version 5.1.0 released! Release 5.1.0, provides following improvements:

imagemagick convert: how to tell if images need to be rotated?

别等时光非礼了梦想. 提交于 2021-01-01 04:40:35
问题 In my rails app, i let the user upload images to use as thumbnails for resources they've made. I do all the image processing with imagemagick's convert command: i convert to jpg, letterbox it to 800x600px and then make some smaller thumbnail versions of that. This is all working fine. The problem is that some images that have come off my iPhone, for example, have the wrong orientation. My desktop seems to variously deal with this: when i see the tiny thumbnail for the image in the file

如何在 Linux 终端查看图像 | Linux 中国

北城以北 提交于 2020-12-25 13:42:29
Linux 有很多用于查看图像的 GUI 应用。但我从来没有尝试过用任何命令行应用来查看它。 来源: https:// linux.cn/article-12948- 1.html 作者:Magesh Maruthamuthu 译者:geekpi (本文字数:2672,阅读时长大约:3 分钟) Linux 有很多用于查看图像的 GUI 应用。但我从来没有尝试过用任何命令行应用来查看它。 幸运的是,在使用 ImageMagick 工具 时,我得到了一个从终端查看图像的命令。命令名是 “display ,它是 ImageMagick 工具的一部分。这是一个很好的工具,允许类 UNIX 用户从终端查看图像。 此外,我还为此用途得到了另一个很好的工具,叫做 FIM。 我们将向你展示如何安装并使用它从 Linux 终端查看图像。这些命令使用系统的 帧缓冲(framebuffer) 直接从命令行显示图像。 如何使用 display 命令从终端查看图像 ImageMagick 是一个自由开源、功能丰富、基于命令行的图像处理工具。它用于创建、编辑、合成或转换位图图像。它可以读取和写入各种格式(超过 200 种)的图像,包括 PNG、JPEG、GIF、PDF、SVG 等。它可以调整图像的大小、镜像、旋转、转换图像、调整图像颜色、应用各种特殊效果等。它支持批处理,允许你一次处理所有图像。 如何安装

php中函数禁用绕过的原理与利用

早过忘川 提交于 2020-12-24 18:38:19
bypass disable function 是否遇到过费劲九牛二虎之力拿了webshell却发现连个scandir都执行不了?拿了webshell确实是一件很欢乐的事情,但有时候却仅仅只是一个小阶段的结束;本文将会以webshell作为起点从头到尾来归纳bypass disable function的各种姿势。 本文涉及相关实验: 绕过函数过滤 (通过本实验学会通过宽字节方式绕过mysql_real_escape_string()、addslashes()这两个函数。) 从phpinfo中获取可用信息 信息收集是不可缺少的一环;通常的,我们在通过前期各种工作成功执行代码 or 发现了一个phpinfo页面之后,会从该页面中搜集一些可用信息以便后续漏洞的寻找。 我谈谈我个人的几个偏向点: 版本号 最直观的就是php版本号(虽然版本号有时候会在响应头中出现),如我的机器上版本号为: PHP Version 7.2.9-1 那么找到版本号后就会综合看看是否有什么"版本专享"漏洞可以利用。 DOCUMENT_ROOT 接下来就是搜索一下 DOCUMENT_ROOT 取得网站当前路径,虽然常见的都是在/var/www/html,但难免有例外。 disable_functions 这是本文的重点,disable_functions顾名思义函数禁用,以笔者的kali环境为例

Imagemagick SVG to PDF conversion image quality is bad

我的未来我决定 提交于 2020-12-09 05:20:05
问题 We are trying to convert an SVG (width 737, height 521) to PDF of A4 dimensions. The problem is that the quality of images generated is really bad. Here's what we are doing SVG (with remote image URLs): <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="737" height="521"> <g class="background"> <title>Background</title> <image x="0" y="0" width="737" height="521" id="svg_1" xlink:href="http://static.inkive.com/assets/img/backgrounds/default.svg"/> </g><g