On a previous project I tested a lot of these on Windows and they either didn't work at all or still required rendering and re-encoding or seemed to work but messed up the file.

With long GOP formats, deleting frames requires reading the file, decoding and materializing the missing frames, updating the GOP and all relevant data structures, then closing the file and hoping nothing got messed up. So deleting a few frames is much more complex than deleting frames from an MJPEG video file where every frame is present as a separate JPG image. Most of the frames are not even there - they are eliminated during the encoding process, and only data about frame differences is stored. MP4 or any H.264 codec is a 'long GOP' format. If you are talking about specialized utilities to extract or delete frames within a video file without re-rendering, this is difficult to do. For Macs, possibly the least expensive best program is iMovie. You then must render and export the edited material. Any true video editing program will let you delete frames.

Avidemux 2.6 mac