Best free way to split or join .MP4 files?

[Nagashi]

So what are some good hassle free programs out there that I can use to split and join .MP4 video files (with audio)?

[Baldrick]

Mymp4boxgui. Or if you want a preview use avidemux.

[pumpysworld]

I'm using the latest version of Freemake Video Converter, which can use the original video and audio settings of the files to be joined.

[yetanotherlogin]

I was looking for the same thing, and will try Freemake Video Converter to join several MPG files (MPEG-1/2 mpgv 720x576 50fps + A52 AC3 a52 48KHz).

Am I correct in understanding that, due to variable bit rates, it's not safe to simply run "copy /b file1.mpg+file2.mpg output.mpg"?

Thank you.

[doroty76]

honestly i tried freemake and does not work, no much quality as any wanna be freeware (that i am not sure it is).
Splitting a mp4 means that you have to cut at the GOP, but GOP accuracy is not so good.
I know only one software that can split a video (and eventually rejoin it) and that is second-wise precise and that is compatible with MP4 and, most of all, does not need to re-encode.
It's called SPAMALOT and so far is the best one i could find.

[roderickllewellyn]

Hello All! I've tried a number of these programs; most of them simply don't work... and I'm a VERY experienced software engineer.
avidemux: extremely confusing, had a lot of difficulties synchronizing on a key frame. It would often get into loops of the form "can't advance to point <X>" from which the only escape was to use task manager to terminate the program. Once I got that part to work, it split off the section I wanted and saved it. Only problem was it consisted of 24 mins of black frame, which was not the original!
AIM's splitter-joiner: couldn't even open an MP4 file, simply said "cannot play <filename>". Failed after merely 10 secs of testing.
Freemake: failed a test but I don't remember which.
CUDA video converter: cannot load .VOB files correctly; it will often tell you that a file of 24 mins duration, say, (which plays fine in other programs) is of 2 mins duration, or sometimes zero and that's all the program will recognize.
I'm actually willing to pay for a good solution to general conversion, splitting, and joining, but it's nice to be able to evaluate them first. So far, I haven't seen one program that correctly does it all. Handbrake appears to encode to .mp4 correctly, but has no splitting or joining capabilities. All other programs I've tried for that latter functionality failed in some way within minutes of my trying them. Overall software quality in this field appears to this engineer to be shockingly low. Even modest testing in the lab should have revealed these problems.

[Baldrick]

You wont find any good free mp4 editor.

I would try a commercial editor like Solveigm video splitter or videoredo h264 suite...but even they aren't perfect.

[roderickllewellyn]

Hello Baldrick, Thanks for reply. I'm willing to spend reasonable money - I don't demand free lol. I've been evaluating programs which give free eval copies. Yesterday, I tried Aimrsoft's program "Total Video Converter". It appeared to actually work correctly (it's about $60). Then, when I cancelled an operation, it froze my machine. Several reboots and tries later, with freezes occurring pretty much upon doing anything inside that program, my machine no longer makes it thru the Windows startup; even the startup recovery has failed; my computer is now effectively dead. It's possible this is a pure coincidence and there is a hardware problem. Some of these programs including this one use the NVidia GPUs to accelerate encoding and it is conceivable that this is related, as I did notice during the reboot and fix-attempt sequence one blue screen involving the video driver.

I have gotten a reply from AimOne (NOT same as Aimrsoft lol) about their splitter/joiner recommending I install the K-Lite Codec.

Once I get my pc running again, I will look at the program you recommend.

Thanks!

[Baldrick]

It sounds really good....

[GlenMeiring]

I have finally found a solution to this issue that worked for me. I have had similar problems to others with the audio sync problem, but I just tried this using the -f concat option with ffmpeg and it worked - with no audio sync issue.

I had to download the latest version of ffmpeg for this to work. Here is a link to the ffmpeg documentation describing how to join .MP4 files:
How to concatenate (join, merge) media files

Good luck, hope it works for you.

By the way, in my case, I was trying to concatenate 150 files from my Canon HF M50. Every time you hit the pause button, you get a new file, which is ok. But I want to merge all of the clips into one file when I'm all done. Since all of my files used the same codecs, I used the first example in the document above. Since it uses -c copy (-c is what codec to use, copy means just copy existing, don't transcode) it goes very fast, AND there is no loss in quality since it is not transcoded.

The hardest part is creating a text file with all of the files you want concatenated. It's not hard, just a pain.

Well, I hope this works for you all.

[glenpinn]

avidemux: extremely confusing, had a lot of difficulties synchronizing on a key frame. It would often get into loops of the form "can't advance to point <X>" from which the only escape was to use task manager to terminate the program. Once I got that part to work, it split off the section I wanted and saved it. Only problem was it consisted of 24 mins of black frame, which was not the original!

Freemake: failed a test but I don't remember which.

Avidemux works brilliantly with splitting and joining mkv / mp4 files, never have an issue, even 1080/50p files.

Freemake is the biggest piece of crap i think i have ever seen, looks like a kid created the user interface while playing in a candy store (horrid looking thing it is) and it might be free, but the makers actually get paid to incorporate 2 apps into its installer, forcing you to "untick" the boxes for those other apps during installation, and when you get it installed and open it, a big box appears asking you to install the "black bar removal" tool" which they then ask for a $9.99 donation to do it ????

[yetanotherlogin]

I have finally found a solution to this issue that worked for me. I have had similar problems to others with the audio sync problem, but I just tried this using the -f concat option with ffmpeg and it worked - with no audio sync issue.

Thanks for the info.

My camcorder saves files as MPEG-PS with video MPEG2 and audio AC-3 6 channels. I'd like to join the multiple 2GB files it creates, and to shrink the file, convert video to H264 and audio to stereo.

Can ffmpeg do this?

[glenpinn]

You wont find any good free mp4 editor.

I would try a commercial editor like Solveigm video splitter or videoredo h264 suite...but even they aren't perfect.

hi, i actually started using VideoRedo 2 days ago, because of my frustration with some of the open source software i have been using, not for encoding/conversions, but for file splitting inaccuracy.

tsMuxer is a great tool to join m2ts files with, no issues, but splitting is not very frame accurate so i gave up.

XMedia Recode is great to convert, but file cutting, again not great.

handbrake is only for mp4 and mkv conversions.

Redo, in my opinion is the best of the file cutting tools, it appears to be more accurate than anything i have used, and it joins just about any type of files brilliantly, and outputs to just about any format as well.

for my testing over 2 days, i was able to confidently walk away and say that Redo does every single job i need any tool to do, where i needed a combination of at least 3 open source tools to do everything i needed confidently.

i love handbrake and XMedia Recode as conversyion tools, but for the best all in one, my $100 was very well spent on Redo, bought a license today, best thing i have bought for years.

solveigmm, i actually tried that several times, and it has the most rediculous user interface for file cutting i have seen, having to "add markers" every time you select a start/end point.

Redo just uses 2 markers, and you have buttons you click on depending on the action you require the markers to perform.

cheers

[JazJon]

You wont find any good free mp4 editor.

I would try a commercial editor like Solveigm video splitter or videoredo h264 suite...but even they aren't perfect.

+1

I have both, if one doesn't work the other will.

[verizon]

If you have a Mac, use Quicktime to split the MP4 files. Open the MP4 file with Quicktime Player. Edit -> Trim. Move the yellow line where you want to have the clip divided in to 2 parts. Select Trim button. Done !

[Michael REMY]

Mymp4boxgui. Or if you want a preview use avidemux.

My MP4Box GUI just managed to split a broken mp4 file that yamb and boilsoft spliter failed to split it !

thank for this free software ! long life to My MP4Box GUI

[steve6]

I have been using mp4 joiner to join some files, and found it very good. it does have ffmpeg within it's directory.
The only thing i don't like about it is that you have to keep clearing the previous list of files one at a time. or close the program, and start again.
But from what i can see it does the job well. it took about 2 minutes to join 13 files of about ten minutes each together.

[steve6]

free video joiner.
supposed to work with more than mp4s. I tried joining 4 mp4 files together. You can output it to a specific video format too. i chose mp4. But the program decided to convert the files from mp4 to mp4. I found it too slow, so gave up on it.

to join flv files together.
flvjoin does the trick
freeware

[glenpinn]

free video joiner.
supposed to work with more than mp4s. I tried joining 4 mp4 files together. You can output it to a specific video format too. i chose mp4. But the program decided to convert the files from mp4 to mp4. I found it too slow, so gave up on it.

the problem with joiner tools, if the videos you want to join do not share the same attributes, the output file will not be created unless it gets re-encoded, and the time it takes depends on the type of pc you have, and the software you are using.

[racer-x]

MpegStreamClip works great for this even on 4k sources. Make sure to cut on key-frames only.

[muncrief]

You can use ffmpeg. Following is an example if you're using windows:

Make a text file with all input videos like this:

# This is a comment
file 'G:\adir\part1.mp4'
file 'G:\adir\part2.mp4'

Assuming that you named it "input.txt" execute this command:

ffmpeg -f concat -i input.txt -codec copy output.mp4

That's it! Your joined file is output.txt. Note that you may get a warning like "[mp4 @ 0000000002bfb480] track 1: codec frame size is not set" but everything should work fine.

Note that you could also execute the command:

ffmpeg -f concat -i input.txt -acodec ac3 -vcodec copy output.mp4

And you wouldn't receive a warning, but the audio may not be selected correctly. For example when I used this command I got Dolby Digital 5.1 audio instead of the full Dolby Digital 5.1 EX audio. The first command works better because it automatically selects the correct codecs.

I hope this works for everyone! Cheers!

[Michael REMY]

well, since a bunch of years i use Boilsoft video splitter which have in my head 2 drawback only :
- cost 30€ but do the job
- only split in 3 parts each time (or 2 part if you begin from start or to the end), so it can't just split & extract a middle part, you will always got 3 files... (very boring for big file split cause you need to forecast many disk space)

i wish so much there will be a day in my dream a tool for mp4 like "TSSplitter.exe" whichj is free and portable and do the job but only for TS video file.....
if someone knew a such TSSplitter.exe for MP4, please do my dream !

have a good day
Mike

[jbellies]

Like many of the early posters in this thread, I had trouble with free utilities in joining MP4 files. In particular, Yamb and My MP4 Box GUI did not work for me. I also tried tsMuxeR, but the error was mine, as I don't believe it is designed to join MP4 files at all. The more recent MP4 joiner did work, although its interface is clunky.

However, if you can contrive to receive your files to be joined in MKV (such as in a popular yew-tube 4ownloader, you can select MP4 or MKV), it is much smoother. In mkvmerge 8.2.0 (distributed as part of mkvtoolnix), you "add" the first file to be joined, then "append" all the others. In appending, you can choose multiple files, and mkvmerge will sort them alphabetically. (This is unlike MP4 joiner which makes you append one file at a time, and unlike some other utilities which contrive to add the files in reverse or random order). The only other adjustment I make is to change the output filename (though the one they suggest is unique (unlike Yamb) and good enough). Then click "start muxing" and the result is almost instant. I've not seen it take more than 1 second.

I also find the MKV files are smaller at equal or better quality than MP4. I am tempted to go even more off-topic, but will stop.

[jgg]

Video to Video (v.2.9.6.10) joins mp4 files just fine. I don't think there's a "split" function, though.

Under "Tools" it says "Join Video Files".

I guess it's only for Windows, though. I'm using it on a Win 7prox64 machine with 12gb RAM.

[nick1357]

VideoReDo will work for joining, splitting, etc.
I have used it for several years. I believe it is the best out there (couple issues, but overall has helped me out tremendously)

the JOIN function allows you to join two or more files as a simple operation.

to CUT sections, you operate on the specific MP4 (or whatever) file you wish; there is CUT or SCENE mode, in the program, and you select the sections you want to save (can be multiple ones in a single file), then SAVE the final video, and the sections you did not select won't be in the final file.
It has an Ad Detective to scan files to automatically remove ads (fairly decent, sometimes some ov movie gets clipped, so do a manual check of te final results)

but overall an excelent program

One issue I just found is that I have some MP4 files that have been captured at variable rate. When I cut/trim them, there are audio and video sync frames that get removed. (it actually did not affect the quality, and was not a re-code for this project). The reason is that VideoReDo (and other programs) have problems handling variable rate.

BUT, overall, fantastic program

[Pawpcorn]

OMG!!! After EVERY OTHER WAY, EVERY other program FAILED....!!! Your advice worked FANTASTIC, with ZERO loss of resolution!!!

Thank you SO MUCH!!!!!

{major hugs},
Pawpcorn

You can use ffmpeg. Following is an example if you're using windows:

Make a text file with all input videos like this:

# This is a comment
file 'G:\adir\part1.mp4'
file 'G:\adir\part2.mp4'

Assuming that you named it "input.txt" execute this command:

ffmpeg -f concat -i input.txt -codec copy output.mp4

That's it! Your joined file is output.txt. Note that you may get a warning like "[mp4 @ 0000000002bfb480] track 1: codec frame size is not set" but everything should work fine.

Note that you could also execute the command:

ffmpeg -f concat -i input.txt -acodec ac3 -vcodec copy output.mp4

And you wouldn't receive a warning, but the audio may not be selected correctly. For example when I used this command I got Dolby Digital 5.1 audio instead of the full Dolby Digital 5.1 EX audio. The first command works better because it automatically selects the correct codecs.

I hope this works for everyone! Cheers!

[pumpysworld]

For converting MP4 to MKV and then splitting it, I first used Video Container Switch to convert MP4 to MKV, then MKVMerge GUI to split the MKV.

[Baldrick]

For converting MP4 to MKV and then splitting it, I first used Video Container Switch to convert MP4 to MKV, then MKVMerge GUI to split the MKV.

You can add mp4s directly in mkvmergegui. And then split.

[frugalbrutus]

Same here - tried many things, this is the ONLY thing that has worked.
THANK YOU from me too!!!!!!!

OMG!!! After EVERY OTHER WAY, EVERY other program FAILED....!!! Your advice worked FANTASTIC, with ZERO loss of resolution!!!

Thank you SO MUCH!!!!!

{major hugs},
Pawpcorn

You can use ffmpeg. Following is an example if you're using windows:

Make a text file with all input videos like this:

# This is a comment
file 'G:\adir\part1.mp4'
file 'G:\adir\part2.mp4'

Assuming that you named it "input.txt" execute this command:

ffmpeg -f concat -i input.txt -codec copy output.mp4

That's it! Your joined file is output.txt. Note that you may get a warning like "[mp4 @ 0000000002bfb480] track 1: codec frame size is not set" but everything should work fine.

Note that you could also execute the command:

ffmpeg -f concat -i input.txt -acodec ac3 -vcodec copy output.mp4

And you wouldn't receive a warning, but the audio may not be selected correctly. For example when I used this command I got Dolby Digital 5.1 audio instead of the full Dolby Digital 5.1 EX audio. The first command works better because it automatically selects the correct codecs.

I hope this works for everyone! Cheers!

[gcharal]

i tried

ffmpeg -f concat -safe 0 -i mylist.txt -c copy output

(see: https://trac.ffmpeg.org/wiki/Concatenate)
but failed with strange errors.

The pure dos command do the job perfectly:

copy /b segment1.ts + segment2.ts + segment3.ts + segment4.ts output.ts