Exact splitting of MKV file

[pwes]

I have a series of DVD's where the episodes are not separated from each other. After ripping to MKV I need to cut where one episode ends and the next starts.

This can only be done with slight reencoding and generation og new keyframes in the selected area. That is acceptable.

SolveigMM Video Splitter for PC can do that but works very slowly and erraticly on my VMWare Fusion XP virtual machine.

So is there a Mac tool for this - or at least a reliable PC tool?

[Baldrick]

Make a mpg from the dvd with vob2mpg or mpeg streamclip instead and then use videoredo to cut the mpeg2 video.


Or are you reconverting(not just ripping) to mkv with h264 video? Then just give up. . Or cut when you are reconverting instead.

[hello_hello]

You probably should be splitting the DVD into episodes and encoding them individually rather than encoding the whole DVD and then trying to split it. If "ripping to MKV" means ripping and converting at the same time, it's probably better to do it in two steps. Rip first and then convert.

My post in this thread briefly explains how to divide a ripped DVD into individual episodes with DVD Shrink. You'll end up with a set of vob files per episode. The same procedure can be used when initially ripping the DVD, so you don't need to rip the whole disc and then divide it into episodes. DVD Shrink can't handle newer types of copy protection correctly, so for those discs you'll need something like AnyDVD running in the background doing the decrypting.

DVD Shrink is Windows software and I know nothing about Mac software, but another alternative might be to use MakeMKV as there's a Mac version. The free version will rip protected DVDs and it should let you rip one title (episode) at a time, giving you an MKV per episode containing the original video and audio. From there you could re-encode each to reduce the file size if you want to. If you still have the original DVDs ripped to your hard drive, you can also open the ripped files with MakeMKV.

[pwes]

The DVD's are formatted as one long movie consisting of the episodes. Talk about ill-authored discs!

But I get the feel to cut before converting to MKV. Seams MPEG Streamclip identifies errors in time codes and is able to fix them, but how to proceed? (edit: - now irrelevant - unless MPEG Streamclip can process all episodes at once

Edit: Using tools you know and at least partly understand is always good. Found another way using a tool I've got at hand. Choosing the relevant cells in DVD2oneX2 will create separate VIDEO_TS folders, that Handbrake can convert to MKV files. I've never found use for the Cells feature before!

[pwes]

Maybe those MKV's inherit a time code problem from the DVD. In the MKV's I cannot go to a given time in it but only play it from a start. So it seems I'm still in need of help here...!

[hello_hello]

The DVD's are formatted as one long movie consisting of the episodes. Talk about ill-authored discs!

Does the DVD just have one large title which is all the episodes? If that's the case, you can most likely still split them into individual episodes with DVD Shrink as the title will be divided into chapters.

Normally when you open an episodic DVD with DVD Shrink and use the re-author function you'll see a title per episode in the right pane (as well as other titles). If there's only one title, you can still drag it to the left pane, then use the editor to select the start and end chapter for the first episode. When that's done, drag the same title to the left pane a second time, then use the editor to select the start and end chapters for the second episode.... and repeat the process for episode three etc. When you're done, use the backup function and you'll have a set of vob files per episode ready for encoding.

[theewizard]

there is No Easy one step, way to do this
rip/copy the dvd to hd
convert to MPEG,no loss no recode
load files in an mpeg editor
mark the start and finish of each episode aka scene cuts
save each episode seperately
yes this is time snd labor intensive
since these are episodes, they will all have approximately the same run time
and you can fast fwd or slide the tine bar indicater up to each cut mark
they don't have to be played real realtime
but editing is 'time intensive' there is mo easy fast way

[pwes]

@hello_hello: I guess DVD2OneX2 does on a mac what DVDShrink is used for on a PC. So I found the Cell feature to split the Episodes. Problem is coming out of Handbrake as h.264 MKV's you cannot jump to any location in the file - only play it from a start.

@theewizard: as you can see I can isolate the episodes. Problem seems to be, that original time code problems from the discs live on in these new VIDEO_TS folders that DVD2OneX2 generates.

Next go is having MakeMKV MKVfi those VIDEO_TS folders, and THEN compress Mkvs in Handbrake.

Edit: That seems to do it: Isolate relevant cells in DVD2OneX2 and rip each episode that way to its own VIDEO_TS folder. Have MakeMKV make that folder into an MKV file and then have Handbrake compress it and mux in the .srt's, that have been synced with the MPEG-2 MKV.

[pwes]

Only fifty to go...!

[photonboy]

EASY SOLUTION!

Use MKVTOOLNIX:

1. Drag the MKV file in
2. "Global" -> "Splitting" -> "split after duration"
3. choose a time to split the video in TWO (the start or end of the part to cut out)
4. "Max number of files" (set to "2").
5. Note: You'll now have two new files split from the main file
6. REPEAT the above process with one of the main files (to split out the part you don't want)

Join the pieces you need back together:
1. Start with fresh MKVTOOLNIX input screen
2. Drag in first part of video
3. click "append"
4. Drag in the second part of the video
5. "Start muxing"

Summary:
You can quite easily and quickly cut out a section by doing the above steps. It works quite well. You may wish to COPY this for easy reference.

[pwes]

@photonboy: MMkvtoolnix can only split at keyframes not at exact time. That's where I started - but I didn't say that from a start!

[Selur]

btw. if the content is progressive x264 encoded content, MKV Cutter might be worth a try,..

[pwes]

@Selur: Thanks for bringing it to my attention (again). Think I heard about it earlier. And in dire need Windows apps are relevant, though I prefer to do things om Mac OS X, when I can. If I decomb NTSC to h.264, will that be progressive or still not?

[Selur]

If I decomb NTSC to h.264, will that be progressive or still not?

Decomb?, if you mean the option present in handbrake, then: yes, assuming it does what it is ment to do it should convert the telecined content to progressive content.

I prefer to do things om Mac OS X

hmm, if it works on windows for you I can probably create a mac version (will need some minor adjustments, but the main thing works cross platform)
-> doh forget that, I just remembered MVK Cutter is using Avisynth so it would require some rewriting to make it Mac compatible (porting the avisynth to Vapoursynth)

[pwes]

@Selur: Yeah I saw the avisynth issue. But it seems MKV cutter may very well be ported to mac one day! And thanks for making it clear to me that is what the Handbrake feature does!

[Selur]

it definitely will, I just need some time and motivation to look into the whole Vapoursynth thing more, the majority of the code of MKV Cutter is already crossplatform compatible,..

[photonboy]

@photonboy: MMkvtoolnix can only split at keyframes not at exact time. That's where I started - but I didn't say that from a start!

No, the above works perfectly. I used it myself. Perhaps you have an OLDER version of MKVTOOLNIX?

As I said above you can "split after duration" such as "01:34:48" (one hour, 34 minutes, 48 seconds).

I cut out the MIDDLE of an MKV video using the exact steps I provided.

[hello_hello]

No, the above works perfectly. I used it myself. Perhaps you have an OLDER version of MKVTOOLNIX?

It'll definitely only split on keyframes. Sometimes there's one right where you want it to be (at the beginning of a scene change etc) but often, there's not. Maybe you just got lucky?

[_Al_]

The DVD's are formatted as one long movie consisting of the episodes. Talk about ill-authored discs!

Just some info about this this, no need to respond to this, just trying to say something, ..., it is actualy well authored DVD. DVD's are not made so rippers press a button and they can convert everything to episodes, but they are encoded for better DVD performance, and those long VOB's can behave better with play all feature, no terrible sound heard making laser head go from the end of episode to the beginning of DVD and then going back to the beggining of other episode. Also using 2pass VBR you get better analyses for the whole video, and teoreticaly you get some more bitrate for some more bitrate demanding scene or actually the whole episode if analyses is done for the whole thing. Episode bitrate demand might differ from episode to episode. There is better bitrate distribution going on here then, it is especially better for home made DVD's, sure this is commercial DVD but rules are basically the same.

[photonboy]

No, the above works perfectly. I used it myself. Perhaps you have an OLDER version of MKVTOOLNIX?

It'll definitely only split on keyframes. Sometimes there's one right where you want it to be (at the beginning of a scene change etc) but often, there's not. Maybe you just got lucky?

Two points:
1) I can split with nano-seconds, not just seconds in the format: "HH.MM.SS.nnnnnnnnn"

2) If the resulting video is too early or too late I simply go back and modify this time

There's really no "lucky" to it since I can choose exactly where I need to be.

As per #2, the only issue is that the time chosen and new split doesn't always match up, but again I can just go back and change the split time. (I start with seconds only, then add non-seconds if needed using half-split method. For example, if 01:00:23 is too early but :01:00:24 is too late I choose 01.00.23.500000000 then split high/low again as needed.).

It seems like a lot of hassle but I don't think I've ever spent more than five minutes to remove a section of video.

Other:
When I use MPC-HC to show video I can show the TIME and the number of FRAMES. The number of FRAMES increases by 24 Frames if the video is 24FPS.

I see no reason why you couldn't split with the same method I use for seconds. Choose the number of FRAMES to split at, then raise or lower this number and repeat the split until you've split at the EXACT frame you want.

[pwes]

@photonboy: I will have to assume it's not h.264 content. That would make it possible AFAIK

[hello_hello]

Two points:
1) I can split with nano-seconds, not just seconds in the format: "HH.MM.SS.nnnnnnnnn"

2) If the resulting video is too early or too late I simply go back and modify this time

There's really no "lucky" to it since I can choose exactly where I need to be.

Well I picked a random MKV containing h264 video and tried different splitting methods. I used the split on frame number option and the split after duration option. For the first I specified frame number 24, then frame 48. I tried 3 seconds, 4 seconds and 5 seconds. Each and every time the MKV was split in exactly the same place.... at roughly the 10 second point. Obviously modifying the split point by a few nanseconds isn't going to change anything, but here's the first 10 seconds from the MKV if you'd care to try to split it further. If you do manage to split it I'd be interested to learn how you did it.

[Selur]

@hello_hello: (since it was encoded with x264) MKVCutter should be able to cut the mkv you posted.

[photonboy]

10-second split:
I could not split this 10-second file.
However, I tried SEVERAL random videos and they all worked with my above methods. And yes, they were H.264/AVC video codecs.

Perhaps there's a MINIMUM size for splitting?

After your 10-second video failed to split, I tried a 30-second video (Youtube download) and it worked just fine.

Not sure where it's failing for you, but I've tried a huge range of videos with no problems at all (except your 10-second one).

[photonboy]

Update:
I couldn't split that 10-second file even after converting it with Handbrake first (tried MKV and MP4 containers). No idea why.

I took a 9-second video of mine and split it into 4 pieces. There is some issue with YOUR VIDEOS (even after conversion with Handbrake) but I'm just not certain what that is.

[aedipuss]

quite possibly it's all one big gop and there is no place to cut it. mediainfo says.

fps is 24 x 10 seconds is 240 frames which is less than the gop length. you'd have to convert it to something like a lossless avi to cut it.

[hello_hello]

Not sure where it's failing for you, but I've tried a huge range of videos with no problems at all (except your 10-second one).

The reason for the existence of this thread is because the OP couldn't simply cut his MKVs where he wanted to. It's not an imaginary problem.
The reason you couldn't split the sample with MKVMergeGUI is because it'll only split on keyframes. As the entire clip was basically a static image there's only one keyframe..... at the beginning. You can't simply cut the clip in the middle because the rest of the frames rely on data from other frames in order to be decoded fully. The only frame which is encoded without referencing another frame is the first one. That's the way AVC encoding works. The i-frames aren't always where you want them to be.
The x264 encoder calculates the difference between frames and if they differ by more than a certain amount, it creates a keyframe. The parameter which adjusts this keyframe placement is scenecut (there's other keyframe patameters above scenecut on that page). The upshot of all that is if you're wanting to cut the video on distinct scene changes it's more likely you can do so because that's where the keyframes will be. However they're not always where you want them to be.

I just went to YouTube and downloaded the first video I saw and had a look at it. I've no idea what encoder setting they use but the longest interval between keyframes was around 2 seconds, so if the clip I uploaded was encoded using the same encoder settings as YouTube then it could probably be cut in 4 or 5 places.... but it wasn't. That's no doubt the reason why you still couldn't cut it after re-encoding it with Handbrake, as there was still only 1 keyframe. YouTube videos are no doubt encoded with streaming in mind so they use i-frames more regularly than video encoded with x264's default settings.

Anyway you can probably check for yourself. Take the 9 second video you split in four places and split it again in 4 different places. I'd be willing to bet you can't for the reason I've explained. If what your saying is correct, you should be able to split it on any frame you choose.

If you care to try Video to Video Converter and use the Commercial Cutter under the Tools menu you can open a video with it and use the navigation bar to preview the video. As you do it'll tell you what type of frame each one is in the status bar. When you release the navigation slider it'll automatically jump to the nearest keyframe as that's where it needs to cut. You can even make note of which frames numbers are keyframes. There's buttons on the navigation bar which simply jump from one keyframe to the next. Once you've made note of some of the frames which are keyframes, open the video with MKVMergeGUI and try splitting the video on a frame which isn't one. You won't be able to.

It's not a new problem. Other types of mpeg4 video have the same splitting limitations (ie Xvid encoded video). If you open an AVI with VirtualDub you'll notice it also has keyframe buttons on the navigation bar. If you want to split an AVI and resave it with VirtualDub (no re-encoding), once again you've got to split in on keyframes.