The 0.7.2 version of PunkGraphicStream for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The actual developer of this free Mac application is David Connolly.
The application's installer is commonly called punkgraphicstream-macosx-0.dmg. The program lies within Audio & Video Tools, more precisely Streaming Media. The most popular version of the program is 0.7. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe.
From the developer:
PunkGraphicStream is a blu-ray subtitle encoder application. With this application, any user can create a blu-ray files from Advanced SubStationAlpha subtitles. In addition, if you wish to use the command line version, after the above installation pgs-cli.sh can be copied to /usr/local/bin.
You may want to check out more software for Mac, such as Oplayera, Machinima Respawn or Jenny FM, which might be related to PunkGraphicStream.