mpgtx faq


Q: I tried to split a file using the ranges option. mpgtx wont split and always will print "results in an empty chunk".
A: Check if you really wrote {650M}. Without the M the value will be possibly read as Byte and not as Megabyte.

Q: I have an elgato EyeTV. mpgtx has problems with the files made by this hardware. Splits wont playback in Quicktime, small segments play only from several seconds from the start.
A: Check The Beta Version of mpgtx 1.4, It should work better. Also its strongly recommended before making splits with any software, use the elgato supplied software and export the clips to "VCD" or "Quicktime". If you dont, the mpeg will have no valid system header, which will make the handling of mpegs by any mpeg splitting software troublesome.

Q: I try to install the Package which comes with mpgtx from this homepage, but the installer wont ask me to authenticate, nothing will happen. What can i do to install the Software?
A: Goto mpgtx-tgz, carefully read the instructions there, download the appropriate version and install. I currently dont know what the problem is, but it looks like only people running OSX prior to 10.2 are the Victims. I guess the package-maker of the 10.2 Developer tools is not 100% compatible to earlier versions of the OS.

Q: How do I make a VCD out of chunks I splitted with mpgtx ?
A: First, try to use the -P option on the split, then try burn with Toasts Video-CD option. If that does not work, convert the chunks with vcdgear -mpg2mpg -toast option, then try again to burn with Toast. One of these methods should be successfull if you mpeg is really VCD-Compatible. If mpeginfo of a mpeg looks like this, its likely it is:
Mpeg 1 System File [Video/Audio]
Muxrate : 1.41 Mbps
Estimated Duration: 03:03.34s
Size [352 x 288] 25.00 fps 1.15 Mbps
Audio : Mpeg 1 layer 2
224 kbps 44100 Hz
Stereo, No emphasis

The above example is an output of a PAL muxed mpeg-1. NTSC will show identical values exept the framerate will be about 29 fps.
If the file is not VCD compatible. you must reencode it with some other tools.

Q: What mpeg-2 formats are supported by mpgtx ?
A: Currently mpeg-2 support is limited to an mpeg-2 video stream + one mp2 audio stream. Ac3 is not supported. Demuxing an unencrypted VOB is possible, but will produce unexpected results. Future versions maybe will not have this problem.

Q: I dont understand the various options like "[-500M]" or "{300M}" or they dont work as expected !
A: If you use the OSX commandline version of mpgtx, make shure you include ranges in double quotes! It seems the shell wont pass them correctly to mpgtx as arguments if not included in the double quotes. You dont need the quotes in the GUI for OSX!
"[]" explained:
A range of "[10M-20M]" will cut out one piece between the two locations.
A range of "]10M-20M[" will cut out one piece between the two locations but will omit the GOPs at 10M and 20M, "[10M-20M[" or "]10M-20M]" are also valid options.
"[-10M]" will simply cut out the start until 10M, "[10M-]" will give you all from 10M to the end of the file.
You are able to use more then 1 "[]" argument for a split: mpgsplit xyz.mpg "[-10M]" "[20M-]" will give you the first 10 and the last 10M of the mpeg. Important Note: In the MacOSX GUI App, you must use a "," as a delimiter between two ranges!
"{}" explained:
"{10M}" will give you 2 parts, one from the beginning to 10M and the rest. If you use a split command like {10M-20M-30M} on a 40M file, you get 4 about 10M size splits.
Important: if you use values like {"00:00:20.10"} mpgtx will split by hours, minutes, seconds, pictures. So if you want to cut of the first 2 seconds of a mpeg the command would be: mpgsplit xyz.mpg "[00:00:02-]". Pictures are numbered from 1 to 60 so they are about 1/60 second. Most times it is not neccessary to specify pictures.

You got it now ? I hope!

Q: mpgtx works fine, but where is the source code ?
A: I will put the source code on the souceforge-site, as soon as the GUI is finished. Also I have to check if it still compiles and works under i386 Linux as before. please wait. note: as of 30 August 2002, the source is now availible at sourceforge!

Q: I try to split several files with mixed kinds, some of them are .mp2 other are .mpg. mpgtx will split some, then it complains about empty chunks and aborts or it will silently process futher without generating output.
A: Looks like its currently not possible to split mixed kind of files in one session with mpgtx. I try to fix this with the next release. As a workaround for now, you should not mix audio and video-files together in the List and do them seperately. This is not a bug of the GUI.

Q: I want to split a muxed mpeg2. mpgtx splits, but the resulting second and further chunks are not playable or are only just plain black.

A:If you got mpgtx Version 1.2 Splitting muxed mpeg2 will most times not work good. Download a newer Version from here. Since 1.3 mpeg2 support is much improved. If this does not help, you could try to first demux the mpeg2 in a .m2v and a .mp2 file. Then split these. Afterwards to get a playable quicktime-movie, convert the .mp2 with madplay to aiff. Then open the Audio in quicktime, select all, copy. Then open video in quicktime, in the edit menu select "add scaled" (needs quicktime pro). You then are able to process the movie with quicktime-tools.

Q: Why is mpgtx needed for splitting or joining mpeg-files anyway, I am able to split or join a mpeg files with rosetta or even zipit?
A: This is not true. If you split a mpeg into chunks by just cutting the file, the original timestamps are still present. Some DVD-Players, Video-Players for PC and Quicktime will refuse to play the Movie correct. Even a very nice player like Videolan will have problems if you try to play a mpeg which is incorrectly joined.

Q: I want to join several mpeg-files, but mpgtx tells me "Specified files are not compatible, if you still want to join them use --force switch".
A: Its most likely, the mpeg files you want to join, have not the same properties. In case of audio files, try to reencode them with the same compression algorithm (mp2, mp3).In case of Video Files, demux the files, then reencode them and mux with the same mux-rate.



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