Add source to figure caption

Question

How can I add a source to a figure? I need to add \ref, \cite or just free text. Something like that:

\begin{figure} [ht]
  \centering
  \includegraphics[width=0.95\textwidth]{res/figure.pdf}
    \caption{Caption}
    \source{\ref{},\cite{} or free Text}
  \label{fig:gliederung}
\end{figure}

Should give me:

The source shouldn't appear in \listoffigures.

Answer 1

There are many ways to do this. The source could be put inside the caption. LaTeX puts the caption in one line, if it fits there. This can be prevented by \hspace{\linewidth} in the following example. When LaTeX tests the width by putting it in a \hbox, then \hspace is taken into account. LaTeX concludes that the caption does not fit into one line and by setting it in several lines, the line break is executed and the white space right after it (\hspace{\linewidth}) is ignored:

\documentclass{article}

\newcommand*{\captionsource}[2]{%
  \caption[{#1}]{%
    #1%
    \\\hspace{\linewidth}%
    \textbf{Source:} #2%
  }%
}

\begin{document}
\begin{figure} [ht]
  \centering
  \captionsource{Caption}{ref, cite or free Text}
  \label{fig:gliederung}
\end{figure}
\end{document}

Alternatively package caption provides an option singlelinecheck, where the testing for fitting into a line can be disabled, using possible multi-line mode always.

Answer 2

I know it makes a lot of time from this post but I had the same problem and found the solution you where looking for. I will post it just in case someone founds it useful.

I took the idea from Gonzalo Medina's post A: How to write a source description under the loaded picture?.

Solution: load the caption package (i.e. write \usepackage{caption} at the preamble of your document) and add this line:

\newcommand{\source}[1]{\caption*{Source: {#1}} }

How to use it: The way I defined this command, it couldn't be more intuitive:

\begin{figure}
    \includegraphics{./imageName}
    \caption{Caption of the image.} \label{imageLabel}
    \source{Source of the image.}
\end{figure}

How it works: The added line creates a new command \source{} with a single input parameter (your source). The * in \caption*{} prevents the figure caption to be accounted for LaTeX and shown in \listoffigures In fact if you type:

\begin{figure}
    \includegraphics{./imageName}
    \caption{Caption of the image.}\label{imageLabel}
    \caption*{Source: Source of the image.}
\end{figure}

Style modification:

I personaly like having all my sources aligned to the right, so I usually define the command above like that:

\newcommand{\source}[1]{\caption*{\hfill Source: {#1}} }

Also the vertical spacing between Caption and Source can be modified adding a \vspace{} command like that:

\newcommand{\source}[1]{\vspace{-3pt} \caption*{ Source: {#1}} }

([+] value will add space and [-] value will reduce it)

I hope it helps!

Answer 3

Alternative command that could be used for achieving similar results based on @Xavi's answer could look like that:

\usepackage{caption}
\newcommand{\captionwithsource}[2]{
    \caption{#1}
    \vspace{-0.5\baselineskip}
    \caption*{Źródło: {#2}}
}

Then when one needs a caption with source one can use a command \captionwithsource{Caption text}{Source text} otherwise normal \caption{Caption text}. The benefit of that command is that you don't have 2 separate commands to use.

One can also rename the command to whatever they want as I understand that captionwithsource can be quite a mouthful. :)

Additionally in my solution instead of using negative \vspace with hardcoded value I've decided to use \vspace{-0.5\baselineskip} which should look just fine for the most font sizes. (Given that one changes it using \captionsetup[font=<size>] command.)

MWE:

\documentclass{article}

\usepackage{blindtext}
\usepackage{caption}
\captionsetup{font=footnotesize}
\newcommand{\captionwithsource}[2]{
    \caption{#1}
    \vspace{-0.5\baselineskip}
    \caption*{Source: {#2}}
}

\begin{document}

\begin{table}[h]
    \centering
    \captionwithsource{This is a table}{https://example.com/}
    \begin{tabular}{|c|c|c|}
        \hline
        Lorem ipsum dolor & Lorem ipsum & dolor sit amet \\
        \hline
        1                          & 2           & 3              \\
        \hline
    \end{tabular}
\end{table}

\blindtext

\begin{figure}[h]
    \centering
    \rule{0.5\textwidth}{0.5\textwidth}
    \captionwithsource{This is a figure}{https://example.com/}
\end{figure}

\end{document}

Result: