Function is_gallery_image 

pub fn is_gallery_image(filename: &str, size_bytes: i64) -> bool

Whether a file of a simulation revision is shown as a picture in the gallery: PNG, JPEG or WebP (by file name) of at most GALLERY_MAX_BYTES. Rendered result pictures are the cheap way to show a CFD or FEA result – nothing is parsed, the browser draws the file.