How to convert .h264 videos to .mpg format.
Converting H.264 Encoded Video Files directly to MPEG Videos (.h264 to .mpg conversion) should be possible and quite straightforward.
Use one of several video editing programs or (online) conversion tools, such as the Freemake Video Converter or MediaCoder, which allow users to import H264 videos and re-save them in MPG format.
Video converting software