I have a LaTeX math equation that I have been trying to convert it into a rich .png image by compiling the .tex file into .dvi and then from .dvi to .png. But I noticed that the Image is small and the background of the image is dark. Below is my code:
\documentclass[30pt]{article}
\DeclareMathSizes{30}{30}{30}{30}
\usepackage{amsmath}
\begin{document}
\pagenumbering{gobble}
\begin{displaymath}
\int\frac{d\theta}{1+\theta^2} = \tan^{-1}\theta+ C
\end{displaymath}
\end{document}