How to Vertically Join Images?

Question

I know how to horizontally join images together; for example:

\documentclass[12pt]{book}
\usepackage{graphicx}

\begin{document}
\thispagestyle{empty}   
\includegraphics[width=0.25\linewidth]{example-image-a}\includegraphics[width=0.25\linewidth]{example-image-b}\includegraphics[width=0.25\linewidth]{example-image-c}
\end{document}  

yields this:

How may I analogously produce a vertical joining of these three images?

Answer 1

Put them, e.g., in paragraphs on their own:

\documentclass[12pt]{book}
\usepackage{graphicx}

\begin{document}
\thispagestyle{empty}
\lineskip=0pt% allow vertical boxes to touch each other

\includegraphics[width=0.25\linewidth]{example-image-a}

\includegraphics[width=0.25\linewidth]{example-image-b}

\includegraphics[width=0.25\linewidth]{example-image-c}
\end{document} 

Note: The default value of \lineskip, which is the minimum vertical distance of boxes, is 1pt with the standard classes, but can be different with other classes. And if your document contains not only the stacked images, you should limit the change of \lineskip using, e.g., an environment like center, flushleft, raggedright, minipage or a \parbox or \begingroup …\par\endgroup or { … \par}:

\documentclass[12pt]{book}
\usepackage{graphicx}

\begin{document}
\thispagestyle{empty}

\centering
\begin{minipage}{.25\linewidth}
\lineskip=0pt% allow vertical boxes to touch each other

\includegraphics[height=.25\textheight]{example-image-a}

\includegraphics[height=.25\textheight]{example-image-b}

\includegraphics[height=.25\textheight]{example-image-c}
\end{minipage}\hfill
\begin{minipage}{.25\linewidth}
\lineskip=0pt% allow vertical boxes to touch each other

\includegraphics[page=1,height=.25\textheight]{example-image-letter-numbered}

\includegraphics[page=2,height=.25\textheight]{example-image-letter-numbered}

\includegraphics[page=3,height=.25\textheight]{example-image-letter-numbered}
\end{minipage}
\end{document} 

Any other environment, i.e., a figure, would also limit the change to the group of that environment.

As an alternative to paragraphs, you can put them just or on lines on their own, e.g., in a center(or flushleft or flushright) environment (or inside a minipage or \parbox):

\documentclass[12pt]{book}
\usepackage{graphicx}

\begin{document}
\thispagestyle{empty}
\begin{center}
\includegraphics[width=0.25\linewidth]{example-image-a}\\[-\lineskip]
\includegraphics[width=0.25\linewidth]{example-image-b}\\[-\lineskip]
\includegraphics[width=0.25\linewidth]{example-image-c}
\end{center}
\end{document} 

(same result as shown above but horizontally centered in the text area).

In this example, the vertical distance is explicitly reduced by -\lineskip, so that the automatic inserted distance of \lineskip for the touching images, is compensated. You can use this also to do real overlapping:

\documentclass[12pt]{book}
\usepackage{graphicx}

\begin{document}
\thispagestyle{empty}
\begin{center}
\includegraphics[width=0.25\linewidth]{example-image-a}\\[-1ex]
\quad\includegraphics[width=0.25\linewidth]{example-image-b}\\[-1ex]
\qquad\includegraphics[width=0.25\linewidth]{example-image-c}
\end{center}
\end{document} 

Note: Just for better visualization of the overlapping I've added an additional horizontal offset to the second and third image.

You could alternatively also use a tikzpicture or picture to place the images wherever you want. But in this case, this would IMHO be an extravagant solution.

Answer 2

Can be achieved with \offinterlineskip within a \parbox. This also ensures that the scope of the line skip manipulation is kept local.

\documentclass[12pt]{book}
\usepackage{graphicx}

\begin{document}
\thispagestyle{empty}
\parbox{0.25\linewidth}{%
  \offinterlineskip%
  \includegraphics[width=\linewidth]{example-image-a}
  \includegraphics[width=\linewidth]{example-image-b}
  \includegraphics[width=\linewidth]{example-image-c}%
}
\end{document}

Answer 3

The joinbox package uses l3coffins to horizontally or vertically join boxes. (Scroll down in the pdf for English documentation.) The outlen option sets the final width. See the doc for more options like setting the alignment.

\documentclass{article}

\usepackage{joinbox}
\usepackage{duckuments} % for random ducks!

\begin{document}

\joinfigs[outlen=0.25\linewidth]{example-image-duck,example-image-duck,example-image-duck}

\end{document}

Answer 4

Set \lineskip to zero.

\documentclass[12pt]{book}
\usepackage{graphicx}

\begin{document}

\begin{figure}[htp]
\centering

\includegraphics[width=0.25\linewidth]{example-image-a}%
\includegraphics[width=0.25\linewidth]{example-image-b}%
\includegraphics[width=0.25\linewidth]{example-image-c}

\caption{Three images in a row}

\end{figure}

\begin{figure}[!htp]
\centering
\setlength{\lineskip}{0pt}

\includegraphics[width=0.25\linewidth]{example-image-a}

\includegraphics[width=0.25\linewidth]{example-image-b}

\includegraphics[width=0.25\linewidth]{example-image-c}

\caption{Three stacked images}

\end{figure}

\end{document}

Answer 5

You can rule out the placing of vertical \lineskip glue by placing horizontal rules of zero height, zero width and zero depth. Via \vskip-\parskip you can cancel out the insertion of vertical \parskip-glue.

This way images occurring on the same page are joined together but breaking the page between images is possible.

This way you don't need to (temporarily) change values of TeX-parameters like \lineskip.

This also works out in the edge case of height and depth of images being smaller than \baselineskip.

\documentclass[12pt]{book}
\usepackage{graphicx}

\parskip=1cm

\begin{document}

%Make sure TeX is in (internal) vertical mode.

%\null \vskip 12cm % when you uncomment this line while paper-format is a4paper
                   % you can see the behaviour regarding page-breaks between images.

\includegraphics[width=0.25\linewidth]{example-image-a}

\hrule height 0pt width 0pt depth 0pt \vskip-\parskip

\includegraphics[width=0.25\linewidth]{example-image-b}

\hrule height 0pt width 0pt depth 0pt \vskip-\parskip

\includegraphics[width=0.25\linewidth]{example-image-c}

\end{document}