Q:

How to hide/remove a picture in footline on title slide only, as a template using beamer class

I am designing a latex template for presentation slides for my company. I use beamer class.
I made the following codes to show a footline on every slide. It is a image on the left, and some words on the right, and the words and image are aligned in the center. However, I want to just remove the image in the title slide.
I have made the following codes
 \setbeamertemplate{footline}{%
         \ifnum\insertframenumber=1
         %
         \else
         \includegraphics[align=c, height=1.5cm]{sim-ci-logo-2.png}%
        \fi        
        \hfill%
        \usebeamercolor[fg]{myfootlinetext}       
        Company confidential. \textcopyright\, 2018 All rights reserved.\hspace*{1em}
        \insertdate{}\hspace*{2em}
        \insertframenumber\kern1em
 }

However, it does not work properly. In the title page, the image is gone, but the words moved to the bottom edge. See the two screenshots below:
This is the title slide's footline, where the words moved to the bottom edge

This is the normal slide's footline.

Do you know how to keep the words in the title slide in the same position as other slides? Thanks in advance.
Note that I have used \ifnum\insertframenumber=1, assuming title slide is always the first slide. As 
@samcarter pointed out How to make the end slide use the same background as title page, while the normal slide use different background?, it is usually a bad idea to make such an assumption, but I do not know how to make it. Any suggestion on that is also appreciated.

A:

In exactly the same way as for the background templates, you can have different footlines:
\documentclass{beamer}
\usepackage{tikz}

\defbeamertemplate{background}{special frames}{%
      \begin{tikzpicture}
      \useasboundingbox (0,0) rectangle(\the\paperwidth,\the\paperheight);
      \fill[color=gray] (0,2) rectangle (\the\paperwidth,\the\paperheight);
      \end{tikzpicture}
}

\setbeamertemplate{background}{
  \begin{tikzpicture}
   \fill[white,opacity=1] (0,0) rectangle(\the\paperwidth,\the\paperheight);
  \end{tikzpicture}
}

\defbeamertemplate{footline}{special frames}{text for special footline}

\setbeamertemplate{footline}{text for normal footline}

\newcommand{\insertendpage}{%
    \setbeamertemplate{background}[special frames]
    \setbeamertemplate{footline}[special frames]
    \begin{frame}
            bla bla
    \end{frame}
}

\setbeamertemplate{title page}{%
    \setbeamertemplate{background}[special frames]
    \setbeamertemplate{footline}[special frames]
    \begin{frame}
            text text
    \end{frame}
}

\begin{document}

\titlepage

\begin{frame}
  Slide 2
\end{frame}

\insertendpage

\end{document}

Quick hack: If you don't want to worry about the vertical position, replace the image by some invisible element of the same height, e.g. a \rule{0pt}{1.5cm}

