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I have a TV set that allows me to plug in a USB hard drive and will play movies in it. It supports a surprisingly wide range of codecs, but as I learned yesterday (the ugly way), while it'll play files over 2Gb, it can't read past the 2Gb mark, so it'll jump to the next movie without playing the ending...

I now have a whole bunch of 1080p movies over 2 hours long that I want to watch, and it doesn't look like there's a firmware update for my TV that'll fix this, so...

Does anyone know of some free program that'll split a movie file in two?

I'm looking for something that will "remake the header" and actually split the file in two, not something that'll treat it as a stream of frames and re-encode it (ie, something that'll take seconds to run, not hours, and will keep image quality intact).

If said program could also do the same for the subtitle file, that'd be ideal, although if it doesn't, I can probably code something that'll do that for me, if I know the exact point at which the movie was cut.

The movies in question are all either "mkv" or "mp4", and the subtitle files are all .srt

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For which operating system? – Flimzy Jul 3 '11 at 19:49
up vote 2 down vote accepted

SplitMKV will do this: SplitMKV Development thread at

It is a command-line tool however, but fairly simple to use - and importantly has the subtitle support you require. It is based on MKVMerge, which performsthe video splitting, and SplitMKV itself takes care of the subtitles; correcting the offsets for the split output.

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Thanks!! Will it also split an MP4 file? – Daniel Magliola Jul 3 '11 at 12:17
This thread will answer that particular question (assuming you are comfortable with command-line tools!):… – Ruairi Fullam Jul 3 '11 at 17:59
Yes, awesome, that ffmpeg command line did it, thanks! I now need to play around with the subtitle files, because the split isn't exact, there is some overlap (i'm assuming, because of keyframes), but those are text files, so that's the easy part. Thank you! – Daniel Magliola Jul 4 '11 at 8:07

In LINUX (Ubuntu) mkvmerge GUI is an excellent tool, but...

Depending on WHERE you are going to play the split files (blurays, tvs, especially), you MIGHT have problems with header compression. remove compression in GUI (older versions) or at command line:

mkvmerge --split 1G --compression 0:none --compression 1:none --clusters-in-meta-seek -o "output.mkv" "input.mkv"

This command will split the input.mkv file into 1GB segments input-001.mkv, input-002.mkv, etc.

In general, if the file plays on your computer but does NOT play on tv or disc player (bluray, dvd), your problem will usually be header compression.

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It certainly worked for me, so +1 – sme Sep 15 '14 at 19:53

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