It is difficult, if not impossible, to cut the movie before encoding it, because the MVC decoders do not support seeking. You MUST therefore encode everything. (The only thing that you can easily do is limit the total number of frames, and therefore cut the end of the movie, but you cannot easily cut something in the middle during the encoding to 3D-SBS or T&B.) Furthermore, you have to cut the audio, subtitles and chapters too, so cutting the video is not sufficient.
IMO, the easiest way to cut the movie at more or less precise points is the split feature of MkvMerge. Here is the explanation of the method. Since you know already the frame numbers where the movie must be cut, I will not explain how to find them.
- Begin by creating a BD3D2MK3D project for your movie. Do not encode it immediately.
- Here, you should determine exactly the frame numbers and time codes of the parts you want to cut. You know them already.
- Edit the file "chapters_3D.qpfile" (in the project directory) with notepad. That file contains the frame numbers of the beginnings of all chapters. Verify if the frame numbers of your cut points are in that file, and if it's not the case, add them at the right places, followed by a space and the letter i in upper case. (The frame numbers must be in increasing order, one per line!) This will force x264 to create an I-frame at the specified frames. Since you can cut the video only at i-frames, it's important for precise cut points. But as I wrote above, you can omit this part, and hope that the final cut points will be approximately where you want them, if you don't know the exact frame numbers.
- You can now encode the 3D movie normally by launching __ENCODE_3D_LAUNCHER.cmd as usual. The whole movie will be encoded, and the complete MKV will be created.
- When the final 3D MKV has been created, open it in the MkvToolnix GUI. Go to the Multiplexer -> Output tab, and enable Splitting by selecting the split mode "After specific timecodes". In the Timecodes field, adds the timecodes of your cut points, separated by comas. You need the time codes here, not the frame numbers! But you can compute them easily by dividing the frame numbers by 24/1.001. There are several syntax for the time codes, but usually I prefer to specify them as a number of ms. In your case, you can use: 14139ms,6744529ms,6882125ms,6957158ms . Leave the Maximum number of files to "Unlimited".
- Then, remux the MKV by clicking the "Start multiplexing" button. Several MKV files will be created.
- When it's finished, play each file to verify if the cut points are at the right positions, and delete the parts you don't need (the credits). If some cut points are not perfect, you can try to change slightly the time codes and go back to step 5, but if you have not specified the I frames of the cut points in the qpfile, you may not be able to cut exactly where you want.
- Finally, relaunch MkvToolnixGUI, and drag and drop the first part of the movie on its window. Then, drag and drop the second part, and when prompted, select the option "append to an existing source frame". Do this for all parts that must be present in the final MKV.
- When all parts you want to keep have been added that way, change the output file name, and launch the multiplexing. The final file will be created, with only the parts you want.
That seems complex, but in fact, it's really simple, and IMO it's the best way to do what you want. There may be other methods (such as using commercial programs like
VideoReDo) but they are not free or not as precise as the method I've explained here.
Good luck!