Crappy ffmpeg script to create a 720 movie from .png image frames. Transparency in .png images is removed using ImageMagick (mogrify) before creating the video.
Usage: Download the .bat file raw. Drag and drop a .png image onto the .bat and conversion will start. Note that all .png files in the folder will be flattened so put only the files you want to convert in one folder before using the script.