Programs that can close GOPs in mkv and m2ts files without re-encoding?

[Deathbliss]

Yes I did search, most of what I found was DVD related and nobody offered program suggestions.

I am simply looking for any programs that can work with the video stream inside m2ts and mkv files, allowing the user to close GOPs without re-encoding anything.

Failing that a program that can work with the extracted h264 file is fine.

Appreciate the help!
- Deathbliss

[sneaker_ger]

You cannot simply "open" or "close" GOPs. That decision is done on encoding time and cannot be undone without re-encoding.

[Deathbliss]

Assuming that is true, then what programs can re-encode the video stream inside a mkv or m2ts file, using the same settings and quality, as well as close the GOPs in the process?
- Deathbliss

[a451guy451]

You cannot re-encode and keep the same quality.

[Guest]

@Deathbliss

Can you explain why you need to close the GOPs? Maybe if we understand your problem we can help you better.

[Deathbliss]

@sneaker_ger and a451guy451

OK, enough is enough. If you guys don't have anything more to contribute than what, in your opinion/experience I can't do, then please don't post, thank you!

@a451guy451

I know you are wrong. I suspect sneaker_ger might be, but I know you are. You can certainly re-encode a video using the same size and bitrate and come out with something the same as the original file. I know because I have done this, many, many times. I also know that it is possible to leave the settings in an original file the same for the output file. Therefore, no change would be made to the output file in re-encoding if you had a program with the option to close all GOPs and leave everything else the same.

@neuron2 and everyone else

I will not provide file specs because I don't need to. I have investigated this thoroughly and know this is my problem. I have some mkv and m2ts files I want to remux into mp4s to play on the Xbox 360. They will remux and play as they are, but you can't seek during playback (no fast forward or rewind.) If you try the video pauses indefinitely (on the computer) or stops or restarts (on the Xbox.)

Please just provide me a list of programs that allow you to close GOPs. It's that simple. So far it seems TMPGenc is the only one. I'm looking for freeware alternatives.

Thank you -
- Deathbliss

[Asmodian]

x264 defaults to closed GOP.

I have investigated this thoroughly and know this is my problem.

Not too thoroughly or you would know both sneaker_ger and a451guy451 are correct.

I will not provide file specs because I don't need to.

You did notice that neuron2 is a Moderator?

[Deathbliss]

Well I was anticipating his/her next question, but I did answer what they asked me, didn't I?

I find it hard to believe that sneaker_ger and a451guy451 know every program and option in these programs in existence. Therefore the possibility that they are wrong is just as real as the probability they are right.

I find it strange that nobody has just simply answered my question... Is there some "Open GOP" protection movement going on that nobody told me about?
- Deathbliss

[Guest]

So your player on the Xbox 360 doesn't seem to like open GOPs. OK, you have to re-encode with closed GOPS.

There is an exception where re-encoding would not be necessary. For example, an MPEG stream may be encoded with closed GOPs but the encoder erroneously sets the GOP flag as open. As you might expect, this error is very rare and I have seen it in only one use case, all I-frame MPEG2 mezzanine streams from a particular content provider. In that case, my software looks at the temporal reference of the I frame and if it is 0 marks the GOP as closed. To fix the stream, a simple utility could set all the GOP flags to closed.

Your likelihood of having this case is zero, given what you have told us. So you have to re-encode, unless you can find an alternate player that knows how to seek. If you must re-encode, then get on with it, and don't bother about debates about quality loss.

You cannot decode a leading B picture (which starts an open GOP) as if it is an I picture, because it depends on other pictures, including one in the previous GOP.

Is there some "Open GOP" protection movement going on that nobody told me about? I'm not aware of any such movement.

[hello_hello]

@sneaker_ger and a451guy451
OK, enough is enough. If you guys don't have anything more to contribute than what, in your opinion/experience I can't do, then please don't post, thank you!

You've not been given the answer you want so you're shooting the messenger.

@a451guy451
I know you are wrong. I suspect sneaker_ger might be, but I know you are. You can certainly re-encode a video using the same size and bitrate and come out with something the same as the original file. I know because I have done this, many, many times. I also know that it is possible to leave the settings in an original file the same for the output file.

You'll always lose quality when (re)encoding unless you choose a lossless method, but whether it's "noticeable" is another matter. Why would any one program be capable of re-encoding without losing quality while others can't, if they all use the x264 encoder and the same encoder settings? The best you can do is (re)encode using a high enough quality setting or bitrate to make the encode look "something the same as the original file".

Therefore, no change would be made to the output file in re-encoding if you had a program with the option to close all GOPs and leave everything else the same.

Of course the output file will be different. You're re-encoding.
http://mewiki.project357.com/wiki/X264_Settings#open-gop
"Open-GOP is an encoding technique which increases efficiency."
Even if your conclusion was correct, how do you expect to re-encode using a less efficient encoding method (or different encoder settings) and not lose quality? Of course you can compensate by increasing the bitrate etc but the way the output video is encoded is never going to be the same as the source.
The settings used to encode the original video aren't really relevant. You want to re-encode using whichever encoder settings, CRF value or bitrate etc looks "transparent" to you, and of course using whichever encoder restrictions are required for you to play the video on your Xbox.

Please just provide me a list of programs that allow you to close GOPs. It's that simple. So far it seems TMPGenc is the only one. I'm looking for freeware alternatives.

The x264 encoder uses closed GOP by default. Therefore any encoder GUI which uses the x264 encoder should be able to re-encode the video using closed GOP. MeGUI, HDConvertToX, RipBot, FFCoder.....

You don't leave the front door unlocked,
I do unless there's nobody home.
You don't leave the toilet seat up,
Yes I do. All the time.
So don't leave your GOPs open!
There's quite a wide variety of media players in this house. None of them (except maybe the Xbox which is never used as a media player) care if a video uses open GOP. You're of course able to encode your video using closed GOP if that's what your player requires, but to be honest I think we're at the stage where the need to use closed GOP is the exception, not the rule.

[Ghitulescu]

I find it hard to believe that sneaker_ger and a451guy451 know every program and option in these programs in existence. Therefore the possibility that they are wrong is just as real as the probability they are right.

I find it strange that nobody has just simply answered my question... Is there some "Open GOP" protection movement going on that nobody told me about?
- Deathbliss

They (and many other) don't know either what kind of video you have in "your" MKV and M2TS files, because they are just containers, and nothing more.

This is one reason you got no answers.

The second reason is that you insulted other people that were willing to help you, and they won't help you any longer now.

[Deathbliss]

If you had started this thread and received the kind of responses I did you would also be, at the very least, slightly annoyed. I'm afraid I just ran out of patience. I know that when I post an answer I only do so when I have an actual answer. I guess I expect others to do the same. My apologies to anyone offended.

@hello_hello

Thank you for giving me the information I needed. I really do appreciate it! Now all I have to do is figure out how to re-encode an h264/avc video stream using the same settings as the original file, and the end result should be something of equivalent quality. Of course I realize after I posted it that I am wrong here. You can cut the cake in the same place in the same way but you inevitable loose a little each time.

@everyone else

Inside the container is an h264/avc video file, and this is what I seek to close GOPs on. I understand that FFMPEG has a -cgop flag, that any use here?

Well I'm off to bed -
- Deathbliss

[Guest]

If you had started this thread and received the kind of responses I did you would also be, at the very least, slightly annoyed. I'm afraid I just ran out of patience. I know that when I post an answer I only do so when I have an actual answer. Every answer you received in this thread was correct and accurate. Each of the responders had "an actual answer" that was fully correct. You are way out of line here.

In other posts, you make clear your files are re-encoded BluRay movies, and that you did not do the encodes. In this thread you are coy about your sources. So I close this thread for rule 6. You can send me a PM with an explanation if you wish to get the thread re-opened.

Consider this a warning not to discuss such material at this forum.