How to trim a vid precisely?

[Paultx]

I have this vid that starts with a guy speaking for about 14~15 seconds. I want to cut this part off.

I tried Format Factory and VLC and both don't give me a precise way to do it. Since FF started to show annoying errors, I uninstalled it.

But VLC is working well, though it can't do the job perfectly. Let me explain.

When I set 14 secs, the cut vid still showed, like, one frame with the guy's face. So I tried 15, 16, 17 secs, but that damn frame is always there!

I guess there's something wrong with VLC. Any ideas how can I get it done? TIA.

[davexnet]

You'll have to re-encode the video (Avidemux)
or videoredo ($$), TmpgEnc smart renderer ($$)

[blud7]

Can't remember the name of the program here but it just encodes a few frames at the end and beginning of clips so you get accurate cuts without re-encoding the entire thing.

[hello_hello]

I have this vid that starts with a guy speaking for about 14~15 seconds. I want to cut this part off.

I tried Format Factory and VLC and both don't give me a precise way to do it. Since FF started to show annoying errors, I uninstalled it.

But VLC is working well, though it can't do the job perfectly. Let me explain.

When I set 14 secs, the cut vid still showed, like, one frame with the guy's face. So I tried 15, 16, 17 secs, but that damn frame is always there!

I guess there's something wrong with VLC. Any ideas how can I get it done? TIA.

It's because without re-encoding, the video can be only cut on a keyframe (an independently encoded frame). Other frames rely on keyframes and also each other, for information so they can be decoded correctly. If you could cut on a non-keyframe, some of the remaining frames around the cut point wouldn't decode properly. Keyframes aren't always where you want them to be. By default, the maximum distance between keyframes for the x264 encoder is roughly 10 seconds (250 frames), and the minimum distance between them is one second.

A program such as VideoRedo (I think) can cut anywhere, as it re-encodes the frames around the cut point, if you don't cut on a keyframe.

[ProWo]

Mkvcutter claims to cut frame accurate without re-encoding. Try it.

[Paultx]

Can't remember the name of the program here but it just encodes a few frames at the end and beginning of clips so you get accurate cuts without re-encoding the entire thing.

That would be an interesting solution! Hope you can (or other fellows here) remember the name of the program!

[Paultx]

You'll have to re-encode the video (Avidemux)
or videoredo ($$), TmpgEnc smart renderer ($$)

I just tried Avidemux and it did it!

Thank you all guys! Not only for the solution (davexnet), but for introducing me to more tools and possibilities (ProWo, hello_hello, and blud7). You are all great!

[Capuchin]

You should use a proper video editing software like powerdirector or camtasia, they are easy to use and you can get the result you want.

[johnmeyer]

I've spent the last 24 hours trying to find a tool which can cut h.264 on any frame, only re-encode to the next or previous GOP, and then "smart render" (i.e., lossless copy) the rest. VideoRedo (which I own) is the only tool I've found so far and, unfortunately, the video it produces can still be "glitchy" at the points which have been re-encoded (Vegas shows blank frames).

My reason for posting is to let the OP know that, having just tried AVIDemux for the first time, while it lets you cut on any frame, it makes no attempt to re-encode which means you will have pixelization at the beginning of the video if you cut on anything other than the GOP boundary. The good news is that the program warns you, so you can go ahead and fix it before you create slightly corrupted video.

I have a great solution for cutting on GOP boundaries using Vegas to do the cuts; exporting to an EDL list; importing that into Excel where I've written a macro that takes the entire list and creates a ffmpeg batch file that creates all the cuts. However, when I need frame-accurate cuts, this doesn't work, I'm still looking for a solution.

LosslessCut and VidCutter looked like they might work, but they don't.

[davexnet]

https://tmpgenc.pegasys-inc.com/en/product/tmsr5.html
30 day free trial

[johnmeyer]

https://tmpgenc.pegasys-inc.com/en/product/tmsr5.html
30 day free trial

Thanks for that! I got my start in video editing over twenty years ago with TMPGEnc. It will be fun to re-visit it.

[davexnet]

https://tmpgenc.pegasys-inc.com/en/product/tmsr5.html
30 day free trial

Thanks for that! I got my start in video editing over twenty years ago with TMPGEnc. It will be fun to re-visit it.

Yes me too, the old encoder 2.5. Those were the days.
I installed the Smart Renderer myself. There are a ton of options in the clip edit tab,
but to get started for a basic edit, it's pretty simple.
Here's one I did to test it; the key frame at frame 66 is where the old footage was copied.
In the original file, the previous key frame was 3 seconds before frame one here.

You can see a degradation in frames 1-65, but I looked in the source
and you can it there also. There's a clear key frame "bounce" in the original file

[ponens]

Smart Cutter Ps-Ts ($$) usually does a pretty good job. It will sometimes fail if the cuts are short (only 1 or 2 frames in total). Far from perfect, but it usually does okay and is easy to use on mp4 and ts containers directly (which contain avchd or mpeg2).

[mugz8391]

MKVToolNix works great for me and has several useful split modes. Should be easy to split by parts after 00.00.14 and it will cut on the nearest key frame.

EDIT: I just noticed what you said about it not cutting on the frame you want - the tool I've used for that is here:

https://www.solveigmm.com/en/products/video-splitter/

[johnmeyer]

Just looked at MKVToolNix, but it doesn't appear to do anything with h.264 MP4 files. so that won't work.

I tried Smart Cutter Ps-Ts and it crashed when trying to open the h.264 MP4 60 fps video from my Sony CX-700. I tried various settings and options, including changing the GOP setting, but nothing worked. For me, the software is completely useless.

I'll be trying TMPGEnc later today.

[jagabo]

Just looked at MKVToolNix, but it doesn't appear to do anything with h.264 MP4 files. so that won't work.

It will only produces mkv file but it accepts mp4 file as input.

[johnmeyer]

Just looked at MKVToolNix, but it doesn't appear to do anything with h.264 MP4 files. so that won't work.

It will only produces mkv file but it accepts mp4 file as input.

Ah, that wasn't clear to me. Thanks.