extra-dependencies/debian/transcode/transcode-1.1.7/docs/faq

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Q:	I am using version 0.6.x where x <= 14, and I'm having
	some sort of problem
A:	Upgrade to the CVS version, this is the only version
	that is supported.
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Q:	How do I obtain transcode from CVS
A:	There are instructions available at
	http://www.transcoding.org/#cvs (tibit)
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Q:	I now got transcode from CVS, how do I compile
	and install it?
A:	See the INSTALL file.
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Q:	So I got transcode from CVS and compiled it according
	to the directions in the INSTALL file, and now I (still)
	have some sort of problem
A:	Join the transcode-users mailing list
	(see www.transcoding.org) and check the archive if
	your problem has been discussed at the mailing list before.
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Q:	I still have a problem and it hasn't been discussed before.
A:	If your problem is that transcode "hangs" without doing anything,
	that is a known problem which is hard to solve. Often running
	transcode this way: "env LD_ASSUME_KERNEL=2.4.0 transcode ..."
	seems to help.
---
Q:	I still have a problem and it's not that transcode
	hangs.
A:	If your problem is that transcode is killed by a signal
	(e.g. segmentation fault), perform these steps (carefully!)
	- recompile transcode for debugging (see the INSTALL file
	  for details)
	- install it
	- start transcode from within gdb like this:
	  $ gdb transcode
	  (gdb) <transcode command line options>
	- when gdb stops, type these commands:
	  (gdb) where
	  (gdb) bt full
	- now file a bug report in transcode-users, including:
	  * the complete transcode command line your're using
	  * the complete output of the transcode run, with option -q 2
	  * the output of gdb
	- only with a full bug report we can do ANYTHING at all.
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Q:	How do I make a copy of a DVD-9
A:	For german reading users here is a link http://linuxwiki.de/DvdAuthoring (felix)
---
Q:	Finally, there's the questions about the justly infamous
	ffmpeg.cfg file. What are all the parameters and what do
	they mean?
A:	The easiest way to find out is to look at the mplayer manpage at
	http://www.mplayerhq.hu/DOCS/man/en/manpage.html#CODEC%20SPECIFIC%20ENCODING%20OPTIONS%20(MENCODER%20ONLY)
	and scroll down to "lavc"<br />
	If you\'re just going to encode to (S)VCD or DVD, you\'d better use the
	profile support.
	In transcode, you can put these options into a config file (use -q2 to
	generate one) called ffmpeg.cfg (ems, tibit)
---
Q:	What's the difference between -j and -Y?
A:	This one I know. The difference between -j and -Y is only
	the order that transcode does the clipping. In the manual
	page we find

	The video frame operations ordering is fixed:
	"-j -I -X -B -Z -Y -r -z -l -k -K -G -C"
	(executed from left to right).

	So if one needs to do frame clipping and resizing, in a
	specific order, he can choose the apropriate transcode
	options.

	For instance, if one wants to clip and then resize the
	video frame, in this order, he can use -j (clip) and
	-B (resize). In this case -Y and -B would not work, as
	the operation -Y is done after -B.

	There are still two other options for clipping:
	--pre_clip (executed before -j) and
	--post_clip (executed after -Y). (ems)
---
Q:	How do I transcode an avi to mpeg?
PA:	(Partial answer) In this form, your question cannot
	easily be answered. You're talking of _container_
	formats (avi, mpeg) while you probably mean _codec_
	formats.
	<br />
	A _container_ is a file format designed to hold both
	audio and video (and sometimes more) data in a way that
	a player application can play them back	properly (that
	means, with audio and video synchronised).
	<br />
	Examples of container formats are avi, mpeg-ps, mpeg-ts,
	asf, quicktime, mp4.
	<br />
	The _codec_ on the other hand, determines what's inside
	the _container_, it is the (compressed) video or audio
	data itself.
	<br />
	Examples of video codecs are: mpeg1, mpeg2,	mpeg4 (aka
	"divx", "xvid"), realvideo, wmv, dv.
	<br />
	Examples of audio codecs are: mpeg1-layer2 (aka "mp2"),
	mpeg1-layer3 (aka "mp3"), wma, aac, pcm.
	<br />
	BTW in avi container files, there's mostly mpeg4 video
	content and mp3 audio content (although this is
	absolutely not obligatory, use tcprobe to find out).
	If you want to burn material on a SVCD or DVD, you need
	to have the video in mpeg2, the audio in mp2 (or ac3 in
	case of DVD) and both of these in a mpeg-ps (program
	stream aka "vob") container.

	With this information you should be able to refrase
	your question a get a proper answer ;-) (ems)
---
Q:	Peoples' faces are purple!
A1:	This probably means that the u and v planes (Cr/Cb) are
	being swapped. As there is no clean definition whether u
	should be Cr or Cb (and vv), this easily happens. (ems)
A2:	I solved this problem with the -k option to transcode.
	People are no longer purple.  Hence, if you're transcoding
	from YUY2 to YV12 and you get purple people, you need
	to use the -k option. (ems)
---
Q:	People are upside-down!
A:      Use -z. Usually it goes away when you turn on YUV mode with -V. (tibit)
---
Q:	I have installed latest transcode tool from source and
	then from rpm. Whenever I run program it falls over as
	it cannot find export_mp2enc.so.
A:	RPM packages of some distributions are not complete. This is a
	general problem. If you want to use the mpeg2enc export module, you
	will have to compile transcode yourself, or try to find a complete rpm
	on the net. (ems)
---
Q:	Do I need the avifile library to write AVI files?
A:	No. Transcode has its own library for writing AVI files. The avifile
	library is used to enable support for win32 binary codecs. The libavcodec
	from the ffmpeg project has a free implementation for most of these codecs
	anyway. (tibit)
---
Q:	Help! I got lots of "no"s after running ./configure!
A:	This is not necessarily a bad thing. transcode has configure checks
	for some very "obscure" import and export codecs which you probably
	never use anyway. <br />
	If you are sure you have a specific library installed and transcode still
	does not find it, have a look at config.log to find out the reason. (tibit)
---
Q:	When trying to read a DVD I get something like
	<tt> (dvd_reader.c) no support for DVD reading configured - exit. </tt>
	What am I missing, ie what do I need to do to fix it?
A:	You have probably installed transcode from source and you are missing
	the dvdread library. This library (including the -devel packages) must be
	installed at compile time and transcode must find it. If transcode
	found it, it will print <tt>"DVD navigation support with libdvdread
	yes"</tt> at the end of the configure run. (tibit)
---
Q:	I am missing the mp3 import module (import_mp3.so)!
A:	You need to have a recent lame library installed. Including all header
	files (-devel package) (tibit)
---
Q:	How do I calculate the best tcrequant number from within a script
	when going from a DVD9 to a DVD5?
A:	Once you have separated (using tcextract) the audio and the video,
	get the file sizes of the audio and video files.  If you are burning to
	a DVD5, the maximum image size is 4700000000.  So the following
	equation will give you a 'best fit' number.  1.04 is a fudge factor to
	leave space for the file system and other overhead.
	<br />
	If you are including more that one audio stream or a subtitle stream,
	those filesizes must also be subtracted from the maximum dvd image size.

	<pre>
	requant_factor = (video_size / (dvdmax_size - audio_size)) * 1.04;
	tcrequant -i ofile.m2v -o movie.m2v -f requant_factor
	</pre> (cooper)
---
Q:      What options to set in ~/.transcode/ffmpeg.cfg for encoding to dvd with
        ffmpeg, when not using profile support
A:      <pre>vrc_minrate=0
        vrc_maxrate=9800
	vrc_buf_size=1792

        </pre>
	If ratecontrol still is insufficient, try:
	<pre>
	lmin=0
	lmax=10000

	</pre>
	(try lower lmax if still not right) (ems).
---
Q:	What does "Can't step back 17" (or similar) means?
A:	This message comes from the mp3 decoder (lame). It means (since
        mp3 has interdependent chunks) that one ore more previous mp3
	chunks are missing "Can't step back ...". This usually happens when
	the file was split at some time.
	There is not much you can do about it. (tibit)
---
Q:	I have problems encoding with the divx4linux libraries from divx.com
A:	Transcode ships two divx encoder modules. One is divx4 and one is divx5.
	Please note that the `4' in divx_4_linux only stands for the word "for"
	it does <b>not</b> denote the version number.<br />
	Use -y divx4 if you have a really old version of the divx4linux
	libraries installed. The divx5 export module is usuable depended on the
	divx4linux libraries you had installed when you compiled transcode. The
	Developers from divx.com changed their API in a backwards incompatible
	way causeing that -y divx5 either supports the new API or the old one.
	They are mutually exclusive. So if you have problems with -y divx4 try
	-y divx5.
	<br />
	Please note that the current version of the divx4linux libraries
	available form divx.com have a bug on they may segfault on Pentium4
	systems. There is another bug in older versions of divx4linux where it
	crashes when writting data to a FAT32 windows partition. Look at
	http://www.exit1.org/dvdrip/doc/faq.cipp#faq11
	<br />
---
Q:	transcode cannot find libdivxdecore.so/libdivxencore.so/libxvidcore.so ...
A:	The best place to put these libraries is the transcode libdir
	(/usr/local/lib/transcode/ by default). You can find out the libdir of
	your transcode installation by executing <tt>tcmodinfo -p</tt>.
	Transcode will look into this libdir first when searching for a
	library. When that fails, transcode will look at the standard library
	locations. You should make sure that the location of the library is in
	<tt>/etc/ld.so.conf</tt> and don't forget to run ldconfig afterwards.
	You do not need to put the transcode libdir into the dlloader config
	file.
---
Q:	I have VOB files from a DVD which transcode won\'t encode
	correctly. At some point, there\'s a \"broken stream\" error,
	and in the resulting AVI the picture exhibits some artifacts at
	that point and the AV sync is gone from there on. The VOB files
	can be played back perfectly without any problems with various
	players, though.
A:	First, concatenate the VOB files into a single file all.vob .
	Next, use mencoder to generate an AVI file:
	<pre>
	mencoder all.vob -o all.avi -ovc copy -oac copy

	</pre>
	Then process the AVI file with transcode. If mencoder crashes
	(as it did on my system), use
	<pre>
	mencoder all.vob -o all_noaudio.avi -ovc copy -nosound

	</pre>
	which will give you an AVI without sound. Transcode this:
	<pre>
	transcode -i all_noaudio.avi -x mpeg2,null -y xvid,null \\
	          -V -R 1 -o /dev/null --print_status 100
	transcode -i all_noaudio.avi -x mpeg2,null -y xvid,null \\
	          -V -R 2 -o transcoded_noaudio.avi --print_status 100

	</pre>
	Assuming that the \"broken\" AVI file transcode generated before
	is called broken.avi, extract the audio with
	<pre>
	tcextract -i broken.avi -x mp3 -a 0 > all.mp3

	</pre>
	and finally merge audio and video with

	<pre>
	avimerge -i all_noaudio.avi -p all.mp3 -o complete.avi

	</pre>
	This can probably be improved; I was happy enough that it
	worked.  (meier)
---
Q:	How can I save the audio track of a DVD directly to a WAVE file
	suitable for burning onto an AudioCD?
A:	Suppose you want the audio from title 2, all chapters and you want the
	second audio stream:
	<pre>
	  transcode -x null,dvd -i /dev/dvd -T2,-1 -a 1 \\
	  -y wav -J resample -E 44100 -o foo.wav

	</pre>
	The resampling is needed since DVD audio is usually sampled at 48
	kHz. (tibit)
---
Q:	How do I transfer my .avi .mpg .mov. asf .wmv etc. files to DVD so that
	they playback on my stand-alone DVD player ?
A:	A step by step howto can be found at
	http://mightylegends.zapto.org/dvd/dvdauthor_howto.php (rickfharris)
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Q:	What do I need to get the import_im and import_imlist modules?
A:	These modules use the ImageMagick library from
	http://www.imagemagick.org
---
Q:	I do have ImageMagick including the -devel package installed and still
	get no import_im and import_imlist module.
A:	Some distributions ship a ImageMagick-devel package which also needs
	bzip2-devel package installed. Check config.log for details.
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