DPI for imported bitmaps

Question

I am importing a number of .png files into my document as follows:

\usepackage{wrapfig}
    \begin{wrapfigure}{r}{0.5\textwidth}
    \centering
    \vspace{-1.5cm}
    \scalebox{0.5}{\includegraphics{./X.png}}
    \caption{Mycaption.}
    \label{mylabel}
    \end{wrapfigure}

Now, my figures are rather small, as ypu can see I scale them down quite a bit. Still, after adding a few of these figures my document gets rather large (seemingly increasing by just a bit more than the sizes of the figures).

I suspect latex adds them with their full DPI, instead of remapping them to the DPI of the document (thus keeping extra detail).

I havve 2 questions:

• How can I check whether it is so?
• Supposing it were so, what can I do to stop my document from getting so very very huge?

Answer 1

To sum up the comments: TeX doesn't have any concept of a 'document DPI' as it fundamentally does not make sense. DPI in print depend on the output device but that should only have an effect during the actual output. Thus if you want to fiddle with images you have to pre-process with a suitable third-party tool.