下列维基百科图像属于公共领域:
使用\includegraphics
,我将图像合并到一些 LaTeX 代码中,编辑掉边框,然后将剩余部分保存为 PDF。
现在,考虑以下代码:
\documentclass[12pt]{book}
\usepackage{graphicx,tikz}
\begin{document}
\begin{tikzpicture}
\thispagestyle{empty}
\node at (0,8){I would like to darken this sentence.};
\node at (0,7){I would like to darken this sentence.};
\node at (0,7){I would like to darken this sentence.};
\node at (0,7){I would like to darken this sentence.};
\node at (0,7){I would like to darken this sentence.};
\node at (0,7){I would like to darken this sentence.};
\node at (0,5.5){But now I would like to darken this IMAGE:};
\node at (0,-1){\includegraphics[width=.75\linewidth,angle=0,page=2]{clipping.pdf}};
\end{tikzpicture}
\end{document}
生成结果:
我想锐化(变暗)图像;不幸的是,由于它是 PDF,我无法以类似于使代码中的某个句子变暗的方式来做到这一点。
问题:如何使用 LaTeX 锐化(变暗) PDF 图像(例如这个)?
谢谢。
答案1
正如 David 所写,最好在位图编辑器中完成此操作。如果您确实想要,可以使用如下混合:
\documentclass[tikz, border=1cm]{standalone}
\usepackage{graphicx}
\begin{document}
\begin{tikzpicture}
\node at (0,0){\includegraphics{sheep.jpg}};
\begin{scope}[blend mode=color burn, yshift=-16cm]
\foreach \a in {0,60,...,300}
\node at (\a:0.5pt){\includegraphics{sheep.jpg}};
\end{scope}
\end{tikzpicture}
\end{document}