There is a video (1280x720, 17 minutes) I want to show a group, but need to edit out an inappropriate bit at the end, and an inappropriate bit in the middle (towards the end). What's the simplest way to do this? This machine is a MacBook Air. I do have a Chromebook and also a Lenovo, but the Lenovo was just updated to Windows 10 and seems...well, it keeps losing the screen duplication particularly in PowerPoint and sometimes clicking doesn't work, I'd rather use the Mac.
MPEG Streamclip 1.9.3b8. The best “Quick N Dirty” little video clipper app. It’s for when you want to just clip out some tidbits here and there, and re-save WITHOUT re-encoding. [EDIT > “Select In”, “Select Out”, "Cut", <fix timecode breaks>, then "Save As"…] BUT Wait, it does so much more! (like re-encode/convert, etc., if you wish) Anyways, don’t worry that it is listed as a beta, its been a ‘beta’ release for about a decade… Squared 5 - MPEG Streamclip video converter for Mac OS X
I'm not familiar with the software, but are you sure you can make arbitrary cuts without reencoding? There's plenty of software than can make cuts along key frame positions (without reencoding) , but not between key frames. This means that some video that appears before or after a key frame will be included in the cut, which may not be desirable. The only way around that, as far as I know, is to reencode the entire video and then you can place key frames where you want them with absolute precision.
I'm also not familiar with MPEG Streamclip, and its website makes no claim to frame accurate cuts without reencoding. But frame accurate cuts of MPEG streams with (virtually) no reencoding can be done. I believe Womble Editor was the first to do it, and most full-out video editors still do not do it. You almost hit on the technique in your last sentence. In the various types of MPEG, the video is contained in packets of video frames called GOP, or group of pictures, which is a keyframe followed by a number of difference frames. This is fixed at 16 frames to a GOP for standard DVDs, but could be a different and even a varying number in other purposes. If the frame you want to cut at is within an MPEG GOP, Womble creates all the frames of that group, you make your cut at any frame you want, then Womble saves the edited file with keyframes for the uncut remaining frames that were in that group of frames. It only reencodes those specific frames, each becoming an individual full keyframe, the rest of the file that was not cut is copied over without reencoding, the original keyframes and GOPs exactly intact. This works for streaming and computer playback of the edited video file.
Yep, that would be the way to do it with an absolute minimum of reencoding, however Womble ain't freeware (it's kind of pricey actually). I routinely transcode video with ffmpeg and if I need to make cuts in the file, I tell ffmpeg to place a keyframe at whatever timecode, then I can make a clean snip post transcode.
Maybe it’s QuickTime I was thinking of. Create 2 clips and then drag them into a new quick time window together and save as 1 file.
Quicktime easiest and fastest. You used to need Quicktime Pro to do edits, maybe they give it away now? If your editing and export options are greyed out, then they're not giving it away, but all it takes to unlock Quicktime Pro is a serial number, which can be had. iMovie also, but it'll take longer.