how to auto scale images to fit into a slide in org mode export to beamer?

Question

When I insert an image into the slide it gets cropped to fit into the slide. How do make an image to scale to fit in without cropping or padding?

To include an image I use:

#+LaTeX:\includegraphics{curves.jpg}

org file header:

#+startup: beamer
#+LaTeX_CLASS: beamer
#+LaTeX_CLASS_OPTIONS: [bigger]
#+BEAMER_FRAME_LEVEL: 2
#+OPTIONS: toc:nil

and config file contains the following:

; allow for export=>beamer by placing

;; #+LaTeX_CLASS: beamer in org files
(unless (boundp 'org-export-latex-classes)
  (setq org-export-latex-classes nil))
(add-to-list 'org-export-latex-classes
  ;; beamer class, for presentations
  '("beamer"
     "\\documentclass[11pt]{beamer}\n
      \\mode<{{{beamermode}}}>\n
      \\usetheme{{{{beamertheme}}}}\n
      \\usecolortheme{{{{beamercolortheme}}}}\n
      \\beamertemplateballitem\n
      \\setbeameroption{show notes}
      \\usepackage[utf8]{inputenc}\n
      \\usepackage[T1]{fontenc}\n
      \\usepackage{hyperref}\n
      \\usepackage{color}
      \\usepackage{listings}
      \\lstset{numbers=none,language=[ISO]C++,tabsize=4,
  frame=single,
  basicstyle=\\small,
  showspaces=false,showstringspaces=false,
  showtabs=false,
  keywordstyle=\\color{blue}\\bfseries,
  commentstyle=\\color{red},
  }\n
      \\usepackage{verbatim}\n
      \\institute{{{{beamerinstitute}}}}\n          
       \\subject{{{{beamersubject}}}}\n"

     ("\\section{%s}" . "\\section*{%s}")

     ("\\begin{frame}[fragile]\\frametitle{%s}"
       "\\end{frame}"
       "\\begin{frame}[fragile]\\frametitle{%s}"
       "\\end{frame}")))

  ;; letter class, for formal letters

  (add-to-list 'org-export-latex-classes

  '("letter"
     "\\documentclass[11pt]{letter}\n
      \\usepackage[utf8]{inputenc}\n
      \\usepackage[T1]{fontenc}\n
      \\usepackage{color}"

     ("\\section{%s}" . "\\section*{%s}")
     ("\\subsection{%s}" . "\\subsection*{%s}")
     ("\\subsubsection{%s}" . "\\subsubsection*{%s}")
     ("\\paragraph{%s}" . "\\paragraph*{%s}")
     ("\\subparagraph{%s}" . "\\subparagraph*{%s}")))

Answer 1

Another option is to use

#+ATTR_LATEX: :width 1.06\textwidth
[[file:curves.jpg]]

This is described here: https://orgmode.org/manual/Images-in-LaTeX-export.html

For specifying image ‘:width’, ‘:height’, and other ‘:options’, use this syntax:

#+ATTR_LATEX: :width 5cm :options angle=90
[[./img/sed-hr4049.pdf]]

Answer 2

after countless hours of research here is the solution. includegraphics accepts width parameter and by using textwidth variable we could set the correct size.

#+LaTeX:\includegraphics[width = 1.06\textwidth]{curves.jpg}