Converting .str files to .mp4 format.
Converting PlayStation Video Streams directly to MPEG-4 Videos (.str to .mp4 conversion) might be possible.
Use a video editing software or (online) conversion tool, such as SUPER or FFmpeg, which should allow users to import STR files and export them in a more common video format, such as MP4.
Program for multimedia streaming and conversion
A universal all-purpose free media, audio & video converter