ode></em> must be a known compressed image format (such as <code class="constant">GL_RGTC</code>)
            or an extension-specified compressed-texture format.
            The <em class="parameter"><code>format</code></em> of the compressed texture
            image is selected by the GL implementation that compressed it (see
            <a href="glTexImage1D"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>), and should be queried at the time the texture was
        