dvd::rip documentation - FAQ
Author: Joern Reder
Description: All about dvd::rip - the full featured DVD Ripper GUI for Linux, written in Perl - dvd::rip documentation - FAQ
Keywords: dvd, rip, linux, perl, divx, transcode, video, mpeg, gtk, DVD, RIP, LINUX, PERL, DIVX, TRANSCODE, VIDEO, MPEG, GTK

# DOCUMENTATION | dvd::rip - Copyright © Jörn Reder, All Rights Reserved

# 6. FAQ
6.1 dvd::rip sometings hangs during transcoding 6.2 I have trouble with a specific DVD. What should I do? 6.3 dvd::rip can't read my DVD. I get strange error messages after ripping (movie ripped short, chapter is useless) and scrambled preview images / movies. 6.4 What about encrypted DVD's? 6.5 Why complains transcode about a missing VIDEO_TS.IFO file? 6.6 DivX encoding does not work 6.7 Is dvd::rip scriptable? 6.8 dvd::rip often rips the wrong audio channel 6.9 Why is the A/V sync of my transcoded NTSC AVI's so bad? 6.10 Why are the transcoded AVI files often bigger or smaller than adjusted? 6.11 My transcoded movie has colored artefacts 6.12 Is it possible to get a WAV file from my music DVD? 6.13 Can I use different dvd::rip versions in parallel? 6.14 What about the name? dvd::rip, dvdrip and Video-DVDRip. Which one is correct?
## 6.1 dvd::rip sometings hangs during transcoding
That's most likely due to a transcode issue related to NPTL. Try most recent transcode versions (1.0.2 or better) and don't use NPTL with 2.4 kernels but a recent 2.6 kernel. If that doesn't help, you can try to workaround transcode NPTL bugs by enabling the correspondent option in dvd::rip's Preferences dialog.
## 6.2 I have trouble with a specific DVD. What should I do?
First try executing the corresponding command by hand. You can grab if from the logfile, which is presented on the Log page. Sometimes dvd::rip is unable to provide a good error message, this way you often can see, what's going wrong (and please consider this FAQ item to learn what's not going wrong ;) Most problems with specific DVDs are transcode related, so consider quering the transcode mailing list archives resp. subscribe to the transcode mailing list and ask your question there. If you're not sure, you always can post your question to the dvdrip-user mailing list, but be aware that you may be pointed to the transcode list ;)
## 6.3 dvd::rip can't read my DVD. I get strange error messages after ripping (movie ripped short, chapter is useless) and scrambled preview images / movies.
Most probably the DVD is encrypted and your system isn't able to handle this. For the rest of the story please read the next FAQ item.
## 6.4 What about encrypted DVD's?
Copying encrypted DVD's is illegal in many countries. Also it's illegal to provide information about how this could be accomplished. So don't send any questions regarding encrypted DVD's or DVD cracking to the author of dvd::rip or to the dvd::rip mailing list. Corresponding mails will be silently ignored, correspondent posts will be removed from the mailing list archive without notification.
## 6.5 Why complains transcode about a missing VIDEO_TS.IFO file?
That's Ok. The corresponding messages are printed by libdvdread if you transcode files on harddisk (which is the default case with dvd::rip). You see something like this:
      libdvdread: Couldn't find device name.
      libdvdread: Can't open file VIDEO_TS.IFO.
but these are only (very confusing) warning messages of libdvdread, which naturally can't find any DVD device or VIDEO_TS.IFO file if started from a directory with only VOB files in it. Just ignore these messages, and please don't report this as a bug.
## 6.6 DivX encoding does not work
First: the proprietary DivX codec often makes problems under Linux. XviD is the better alternative, so I'd always suggest to use XviD instead of DivX. If you really want to use DivX, read on, hopefully it helps. If you're using the 2003 release of DivX (5.01, resp. 20030428) and have a Pentium IV processor, you need to downgrade to the 2002 version. The Linux versions don't make big differences here anyway. The Pentium IV bug is a known problem and ignored by divx.com, as with other fatal Linux bugs in their software. If you're using the 2002 version (5.01, resp. 20020418) already, there is also a nasty bug. It tries to create a file c:\trace_b.txt, which fails if you work on a vfat filesystem, because this filename is illegal here. For this one a workaround exists. Execute the following Perl one-liner as root (thanks to Christian Marillat) to patch the codec library file (probably the location differs on your system).
       perl -pi.bak -e 's|c:\\trace_b.txt|/dev/null\0\0\0\0\0|' \
       	/usr/lib/libdivxencore.so
This command also creates a .bak file.
## 6.7 Is dvd::rip scriptable?
Yes, somewhat. dvd::rip has command line options which enable you to write small scripts to transcode several projects in a row. Refer to the documentation for details.
## 6.8 dvd::rip often rips the wrong audio channel
Most likely dvd::rip does it right, but you're playing the ripped VOB files with a movie player which is wrong. Do a test transcode of a few hundred frames, play the resulting movie and you'll see, that you have the right audio channel. Note: dvd::rip always copies all audio channels of the movie to the harddisk. It extracts only the selected viewing angle and scans the volume of the selected audio channel in the same run. With the volume scan information it's possible to rescale the volume to the maximum during later transcoding.
## 6.9 Why is the A/V sync of my transcoded NTSC AVI's so bad?
First try the PSU core of transcode resp. enable the corresponding checkbox on dvd::rip's Transcode page. This should fix most NTSC A/V sync issues. If this still doesn't work as expected, please post your issue to the transcode mailing list and provide example material, so the developers can reproduce the problem.
## 6.10 Why are the transcoded AVI files often bigger or smaller than adjusted?
Modern video codecs (like DivX) work with variable bitrate encoding. So the desired bitrate is in fact an average bitrate. But currently most codecs have problems hitting this bitrate overall. Regularly the effective bitrate is somewhat smaller, which is no problem, but sometimes it's bigger, so the files won't fit on the desired number of discs. You can enable multipass encoding for optimizing this. But often the effective bitrate differs nevertheless. We just can wait on better codecs, which hopefully solve this problem finally.
## 6.11 My transcoded movie has colored artefacts
Most codecs don't support frame dimensions which are not divisible by 16. dvd::rip's presets take care of this restriction, but because you can modify Clip & Zoom values by hand, this may still happen. In that case you usually get strange colored shadow or other effects. If you followed this rule, but still get artefacts, please report this as a bug, because this shouldn't happen anymore, since dvd::rip takes care of the correspondent internal options to prevent this (keyword: YUV colorspace resp. transcode's -V option).
## 6.12 Is it possible to get a WAV file from my music DVD?
Yes it is, refer to the corresponding documentation chapter for details.
## 6.13 Can I use different dvd::rip versions in parallel?
Yes, you can. Refer to the corresponding chapter in the installation docs.
## 6.14 What about the name? dvd::rip, dvdrip and Video-DVDRip. Which one is correct?
Depending on the environment all names are correct. The program in general is called dvd::rip, note the lower case and the colons. Because the colons have to be escaped in most shells, the executable is called dvdrip, just to make your life easier. dvd::rip is also an OO Perl program, so it occupies some namespace: Video::DVDRip. From this name the distribution file names are derived: Video-DVDRip-version.tar.gz. That's all ;) In short: write dvd::rip if you're talking about dvd::rip and say dvdrip if your're talking about dvd::rip ;) Ah, I forgot the colons. Perl uses them to separate nested namespaces. Yes, you're right, the name dvd::rip is obviously no Perl namespace, so this is the wrong reason. The true reasons are: the colons look nice and this way dvd::rip distinguishes from many other tools, which call themselves DVDRIP, dvd-rip or whatever ;)

DOCUMENTATION | dvd::rip - Copyright © Jörn Reder, All Rights Reserved