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improved DVD ripping guide by Jason Tackaberry <tack@sault.org>

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git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@12759 b3059339-0415-0410-9bf9-f77b7e298cf2
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diego 2004-07-05 16:27:53 +00:00
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@ -124,7 +124,7 @@ them. This section is about <emphasis role="bold">copying</emphasis>.
<listitem><para>
<emphasis role="bold">Video stream</emphasis> (option <option>-ovc copy</option>):
nice stuff can be done :) Like, putting (not converting!) FLI or VIVO or
MPEG1 video into an AVI file! Of course only
MPEG1 video into an AVI file! Of course only
<application>MPlayer</application> can play such files :) And it probably
has no real life value at all. Rationally: video stream copying can be
useful for example when only the audio stream has to be encoded (like,
@ -132,7 +132,7 @@ them. This section is about <emphasis role="bold">copying</emphasis>.
</para></listitem>
<listitem><para>
<emphasis role="bold">Audio stream</emphasis> (option <option>-oac copy</option>):
straightforward. It is possible to take an external audio file (MP3,
straightforward. It is possible to take an external audio file (MP3,
WAV) and mux it into the output stream. Use the
<option>-audiofile <replaceable>filename</replaceable></option> option
for this.
@ -267,7 +267,7 @@ An example, with MJPEG compression:
<para>
<application>MEncoder</application> is capable of creating movies from one
or more JPEG, PNG or TGA files. With simple framecopy it can create MJPEG
or more JPEG, PNG or TGA files. With simple framecopy it can create MJPEG
(Motion JPEG), MPNG (Motion PNG) or MTGA (Motion TGA) files.
</para>
@ -523,186 +523,420 @@ vcodec=mpeg2video:intra_matrix=8,9,12,22,26,27,29,34,9,10,14,26,27,29,34,37,
<title>Making a high quality MPEG4 (&quot;DivX&quot;) rip of a DVD movie</title>
<para>
Ripping a DVD title into a maximally high quality MPEG4 (DivX) file
involves many considerations. Below is an example of the process when
there is no file size goal (other than perhaps fitting the result into 2GB).
<systemitem class="library">libavcodec</systemitem>
will be used for the video,
and the audio will be copied as is without any changes.
One frequently asked question is "How do I make the highest quality DVD
rip possible? I don't care about file size, I just want the best
quality."
</para>
<para>
This question is perhaps at least somewhat wrongly posed. After all, if
you don't care about file size, why not simply copy the MPEG2 video
stream from the DVD whole? Sure, your AVI will end up being 5GB, give
or take, but if you want the best quality and don't care about size,
this is certainly your best option.
</para>
<para>
In fact, the reason you want to transcode a DVD into MPEG4 is
specifically because you <emphasis role="bold">do</emphasis> care about
file size.
</para>
<para>
It's difficult to offer a cookbook recipe on how to create a very high
quality DVD rip. There are several factors to consider, and you should
understand these details or else you're likely to end up disappointed
with your results. Below we'll investigate some of these issues, and
then have a look at an example. We assume you're using
<systemitem class="library">libavcodec</systemitem> to encode the video,
although the theory applies to other codecs as well.
</para>
<para>
The main assumption of this guide is that you have no specific file size
constraints and have no problem giving up bits in exchange for quality.
While much of the information presented here is useful in any case, some
of it may work against you if you have a file size goal, such as fitting a
video on a CD.
</para>
<sect2 id="menc-feat-dvd-mpeg4-2pass">
<title>Constant Quantizer vs. 2-pass</title>
<para>
There are three approaches to encoding the video: constant bitrate
(CBR), constant quantizer, and two-pass (ABR, or average bitrate).
</para>
<para>
In each of these modes, <systemitem class="library">libavcodec</systemitem>
breaks the video frame into 16x16 pixel macroblocks and then applies a
quantizer to each macroblock. The lower the quantizer, the better the
quality and higher the bitrate. The method
<systemitem class="library">libavcodec</systemitem> uses to determine
which quantizer to use for a given macroblock varies and is highly
tunable. (This is an extreme over-simplification of the actual
process, but the basic concept is useful to understand.)
</para>
<para>
When you specify a constant bitrate, <systemitem
class="library">libavcodec</systemitem> will encode the video, discarding
detail as much as necessary and as little as possible in order to remain
lower than the given bitrate. If you truly don't care about file size,
you could as well use CBR and specify a bitrate of infinity. (In
practice, this means a value high enough so that it poses no limit, like
10000Kbit.) With no real restriction on bitrate, the result is that
<systemitem class="library">libavcodec</systemitem> will use the lowest
possible quantizer for each macroblock (as specified by
<option>vqmin</option>, which is 2 by default). As soon as you specify a
low enough bitrate that <systemitem class="library">libavcodec</systemitem>
is forced to use a higher quantizer, then you're almost certainly ruining
the quality of your video. In general, you should avoid CBR altogether if
you care about quality.
</para>
<para>
With constant quantizer, <systemitem
class="library">libavcodec</systemitem> uses the same quantizer, as
specified by the <option>vqscale</option> option, on every macroblock. If
you want the highest quality rip possible, again ignoring bitrate, you can
use <option>vqscale=2</option>. This will yield the same bitrate and PSNR
(peak signal-to-noise ratio) as CBR with
<option>vbitrate</option>=infinity and the default <option>vqmin</option>
of 2.
</para>
<para>
The problem with constant quantizing is that it uses the given quantizer
whether the macroblock needs it or not. That is, it might be possible
to use a higher quantizer on a macroblock without sacrificing visual
quality. Why waste the bits on an unnecessarily low quantizer? Your
CPU has as many cycles as there is time, but there's only so many bits
on your harddisk.
</para>
<para>
With a two-pass encode, the first pass will rip the movie as though it
were CBR, but it will keep a log of properties for each frame. This
data is then used during the second pass in order to make intelligent
decisions about which quantizers to use. During fast action or low
detail scenes, higher quantizers will likely be used, and during
slow moving or high detail scenes, lower quantizers will be used.
</para>
<para>
If you use <option>vqscale=2</option>, then you're wasting bits. If you
use <option>vqscale=3</option>, then you're not getting the highest
quality rip. Suppose you rip a DVD at <option>vqscale=3</option>, and
the result is 1800Kbit. If you do a two-pass encode with
<option>vbitrate=1800</option>, the resulting video will have <emphasis
role="bold">higher quality</emphasis> for the <emphasis role="bold">same
bitrate</emphasis>.
</para>
<para>
Since you're now convinced that two-pass is the way to go, the real
question now is what bitrate to use? The answer is that there's no
single answer. Ideally you want to choose a bitrate that yields the
best balance between quality and file size. This is going to vary
depending on the source video.
</para>
<para>
A good starting point for a very high quality rip is about 2000Kbit plus
or minus 200Kbit. For fast action or high detail source video, or if
you just have a very critical eye, you might decide on 2400 or 2600.
For some DVDs, you might not notice a difference at 1400Kbit. It's a
good idea to experiment with scenes at different bitrates to get a feel.
</para>
</sect2>
<sect2 id="menc-feat-dvd-mpeg4-crop">
<title>Cropping</title>
<title>Cropping and Scaling</title>
<para>
Play the DVD and run the crop detection filter
(<option>-vf cropdetect</option>) on it. This gives you a crop rectangle
to use for encoding. The reason for cropping is that many movies are
not shot in a standard DVD aspect ratio (16/9 or 4/3), or, for whatever
reason, the picture does not properly fill the frame. So you want to crop
out the pointless black bars when you rip. It also improves the quality
of the rip since the sharp edge of the black bars wastes a lot of bits.
A common aspect is 2.35, which is cinescope. Most big blockbuster
movies have this aspect ratio.
Native DVD resolution is 720x480 for NTSC, and 720x576 for PAL, but
there's an aspect flag that specifies whether it's full-screen (4:3) or
wide-screen (16:9). Many (if not most) widescreen DVDs are not strictly
16:9, and will be either 1.85:1 or 2.35:1 (cinescope). This means that
there will be black bands in the video that will need to be cropped out.
</para>
<para>
<application>MPlayer</application> provides a crop detection filter that
will determine the crop rectangle (<option>-vf cropdetect</option>).
Because MPEG4 uses 16x16 macroblocks, you'll want to make sure that each
dimension of the video you're encoding is a multiple of 16 or else you
will be degrading quality, especially at lower bitrates. You can do this
by rounding the width and height of the crop rectangle down to the nearest
multiple of 16. When cropping, you'll want to increase the y-offset by
half the difference of the old and the new height so that the resulting
video is taken from the center of the frame. And because of the way DVD
video is sampled, make sure the offset is an even number. (In fact, as a
rule, never use odd values for any parameter when you're cropping and
scaling video.) If you're not comfortable throwing a few extra pixels
away, you might prefer instead to scale the video instead. We'll look
at this in our example below.
</para>
<para>
Also, be careful about "half black" pixels at the edges. Make sure you
crop these out too, or else you'll be wasting bits there that
are better spent elsewhere.
</para>
<para>
After all is said and done, you'll probably end up with video whose pixels
aren't quite 1.85:1 or 2.35:1, but rather something close to that. You
could calculate the new aspect ratio manually, but
<application>MEncoder</application> offers an option for <systemitem
class="library">libavcodec</systemitem> called <option>autoaspect</option>
that will do this for you. Absolutely do not scale this video in order to
square the pixels unless you like to waste your harddisk space. Scaling
should be done on playback, and the player will use the aspect stored in
the AVI to determine the correct resolution.
</para>
</sect2>
<sect2 id="menc-feat-dvd-mpeg4-quality">
<title>Quality level</title>
<sect2 id="menc-feat-dvd-mpeg4-audio">
<title>Audio</title>
<para>
Next you need to choose the desired quality level. When there is no
need to fit the resulting file on CDs or the like, using constant
quantizing AKA constant quality is a good choice. That way each frame
is given as much bits as its needs to keep the quality at the desired
level, but multiple encoding passes are not needed. With
<systemitem class="library">libavcodec</systemitem>,
you get constant quality by using
<option>-lavcopts vqscale=<replaceable>N</replaceable></option>.
<option>vqscale=3</option> should give you a file below 2GB in size,
depending mainly on the movie length and video noisiness (the more
noise, the harder it is to compress).
</para></sect2>
<sect2 id="menc-feat-dvd-mpeg4-2gb">
<title>Files over 2GB</title>
<para>
If the file resulting from constant quality encoding is over 2GB big,
you will have to create an index to be able to view it properly.
Either
<itemizedlist>
<listitem><para>
play the file with <option>-forceidx</option> to create an index
on the fly or
</para></listitem>
<listitem><para>
use <option>-saveidx</option> to write an index to a file once and
<option>-loadidx</option> to use it when playing the file.
</para></listitem>
</itemizedlist>
If this bothers you, you may want to keep the file size below 2GB.
Audio is a much simpler problem to solve: just leave it as is. Even AC3
5.1 streams are at most 448Kbit/s, and they're worth every bit. You
might be tempted to transcode the audio to high quality Ogg Vorbis, but
just because you don't have an A/V receiver for AC3 pass-through today
doesn't mean you won't have one tomorrow. Future-proof your DVD rips by
preserving the AC3 stream.
</para>
<para>
There are three ways to avoid this. You can try encoding again using
<option>vqscale=4</option> and see if both the resulting file size
and picture quality are acceptable. You can also use
<link linkend="menc-feat-mpeg4">2 pass encoding</link>.
As you will be copying the audio track as is and hence know its
bitrate, and you know the running time of the movie, you can
compute the required video bitrate to give to the
<option>-lavcopts vbitrate=<replaceable>bitrate</replaceable></option>
option without using
<link linkend="menc-feat-mpeg4">3 pass encoding</link>.
</para>
<para>
The third and possibly the best option may be to slightly scale down
the resolution. The uniform slight softening and loss of detail is
visually more appealing than the blockiness and other artifacts
caused by MPEG compression. Scaling down also effectively reduces the
noise of the picture, which is good, as noise is hard to compress.
</para></sect2>
<sect2 id="menc-feat-dvd-mpeg4-deinterlacing">
<title>Deinterlacing</title>
<para>
If the movie is interlaced, you may want to deinterlace it as part of
the ripping. It is debatable whether deinterlacing should be done at
this stage. The benefit is that deinterlacing when converting to
MPEG4 makes compression better, and viewing easier and less CPU
intensive on computer monitors as no deinterlacing is required at
that stage.
</para>
<para>
If deinterlacing at the ripping stage is a good idea depends on
the DVD. If the DVD is made from film, which was shot at 24 fps, you
can as well deinterlace while ripping. If, however, the original was
50/60 fps video, converting into deinterlaced 23.976/25 fps video
will lose information. If you do decide to deinterlace, you can further
experiment with different deinterlacing filters. See
<ulink url="http://www.wieser-web.de/MPlayer/">http://www.wieser-web.de/MPlayer/</ulink>
for examples. A good starting point is <option>-vf pp=fd</option>.
</para>
<para>
If you are both cropping and deinterlacing, deinterlace
<emphasis>before</emphasis> cropping. Actually, this is not necessary
if the crop offset is vertically a multiple of 2 pixels. However with
some other filters, like dering, you should always crop last, so it's a
good habit to put the crop filter last.
</para></sect2>
<sect2 id="menc-feat-dvd-mpeg4-telecine">
<title>Inverse telecine</title>
<para>
If you are ripping a PAL DVD, which is 25 fps, you do not need to
think about the fps. Just use 25 fps. NTSC DVDs on the other hand are
29.97 fps (often rounded to 30 fps, but that is not what they are).
If the movie was shot for TV, you again do not need to touch the fps.
But if the movie was shot on film, and hence at (exactly) 24 fps,
it has been converted to 29.97 fps when making the DVD. That
conversion where 12 fields are added to each 24 frames of film is
called telecine. For more info about telecine, see a
<ulink url="http://www.google.com/search?q=telecine+field+23.976">
Google search for &quot;telecine field 23.976&quot;</ulink>.
</para>
<para>
In case you have such a telecined DVD, you will want to do inverse
telecine, that is convert the movie to 23.976 fps (29.97*4/5).
Otherwise camera panning will look jerky and awful. You can use
<option>-ofps 23.976</option> for this. Anything that is shown in
theatres is shot on film and needs inverse telecine, TV shows do not.
</para></sect2>
<sect2 id="menc-feat-dvd-mpeg4-scaling">
<title>Scaling and aspect ratio</title>
<para>
For best quality, do not scale the movie while ripping. Scaling down
obviously loses detail, and scaling up causes artifacts and obviously
makes the file larger. Pixels in DVD movies
are not square, so DVD movies include info about the correct aspect
ratio. It is possible to store the aspect ratio in the MPEG4 header
of the output file. Most video players ignore this info, but
<application>MPlayer</application> honors it. So if you are only
going to use <application>MPlayer</application> for viewing the
ripped file, you do not need to scale the movie, just pass
<option>-lavcopts autoaspect</option> to
<application>MEncoder</application> and things will
automagically work right. If you must scale the movie, be
careful about getting the size right especially if you do cropping.
</para>
</sect2>
<sect2 id="menc-feat-dvd-mpeg4-summary">
<title>Summing it up</title>
<sect2 id="menc-feat-dvd-mpeg4-interlacing">
<title>Interlacing and Telecine</title>
<para>
With all of the above mentioned in mind, a suitable encoding command
might be
<screen>
mencoder dvd://1 -aid 128 -oac copy -ovc lavc -lavcopts vcodec=mpeg4:vqscale=3:vhq:v4mv:trell:autoaspect \
-ofps 23.976 -vf crop=720:364:0:56 -o Harry_Potter_2.avi
</screen>
Here <option>dvd://1</option> gives the DVD title to rip. Option
<option>-aid 128</option> says to use audio track 128, and
<option>-oac copy</option> to copy it as is. You'll have to use
<application>MPlayer</application> to find out the right values for
these options.
Almost all movies are shot at 24 fps. Because NTSC is 29.97 fps, some
processing must be done to this 24 fps video to make it run at the correct
NTSC framerate. The process is called 3:2 pulldown, commonly referred to
as telecine (because pulldown is often applied during the telecine
process), and, naively described, it works by slowing the film down to
23.976 fps, and repeating every fourth frame.
</para>
<para>
Options <option>vhq:v4mv:trell</option> for
<option>-lavcopts</option> improve quality versus bitrate, but make
encoding take longer. Especially <option>trell</option> slows
encoding down but also increases quality visibly. If you want to
deinterlace, add a <option>pp</option> filter to
<option>-vf</option>, for example
<option>-vf pp=fd,crop=720:364:0:56</option> (in that order). If you don't need
inverse telecine, leave out the <option>-ofps 23.976</option>.
No special processing, however, is done to the video for PAL DVDs, which
run at 25 fps. (Technically, PAL can be telecined, called 2:2 pulldown,
but this doesn't become an issue in practice.) The 24 fps film is simply
played back at 25 fps. The result is that the movie runs slightly faster,
but unless you're an alien, you probably won't notice the difference.
Most PAL DVDs have pitch-corrected audio, so when they're played back at
25 fps things will sound right, even though the audio track (and hence the
whole movie) has a running time that's 4% less than NTSC DVDs.
</para>
<para>
Because the video in a PAL DVD hasn't been altered, you needn't worry
much about frame rate. The source is 25 fps, and your rip will be 25
fps. However, if you're ripping an NTSC DVD movie, you may need to
apply inverse telecine.
</para>
<para>
For movies shot at 24 fps, the video on the NTSC DVD is either telecined
29.97 fps, or else it is progressive 24 fps and intended to be telecined
on-the-fly by a DVD player. On the other hand, TV series are usually
only interlaced, not telecined. This is not a hard rule: some TV series
are interlaced (such as Buffy the Vampire Slayer) whereas some are a
mixture of progressive and interlaced (such as Angel, or 24).
</para>
<para>
It's highly recommended that you read the section on <link
linkend="menc-feat-telecine">How to deal with telecine and interlacing
in NTSC DVDs</link> to learn how to handle the different possibilities.
</para>
<para>
However, if you're mostly just ripping movies, likely you're either
dealing with 24 fps progressive or telecined video, in which case you can
use the <option>pullup</option> filter <option>-vf
pullup,softskip</option>.
</para>
</sect2>
<sect2 id="menc-feat-dvd-mpeg4-filtering">
<title>Filtering</title>
<para>
In general, you want to do as little filtering as possible to the movie
in order to remain close to the original DVD source. Cropping is often
necessary (as described above), but do not scale the video. Although
scaling down is sometimes preferred to using higher quantizers, we want
to avoid both these things: remember that we decided from the start to
trade bits for quality.
</para>
<para>
Also, do not adjust gamma, contrast, brightness, etc. What looks good
on your display may not look good on others. These adjustments should
be done on playback only.
</para>
<para>
One thing you might want to do, however, is pass the video through a
very light denoise filter, such as <option>-vf hqdn3d=2:1:2</option>.
Again, it's a matter of putting those bits to better use: why waste them
encoding noise when you can just add that noise back in during playback?
Increasing the parameters for <option>hqdn3d</option> will further
improve compressibility, but if you increase the values too much, you
risk degrading the image visibily. The suggested values above
(<option>2:1:2</option>) are quite conservative; you should feel free to
experiment with higher values and observe the results for yourself.
</para>
</sect2>
<sect2 id="menc-feat-dvd-mpeg4-example">
<title>Example</title>
<para>
So, you've just bought your shiny new copy of Harry Potter and the Chamber
of Secrets (widescreen edition, of course), and you want to rip this DVD
so that you can add it to your Home Theatre PC. This is a region 1 DVD,
so it's NTSC. The example below will still apply to PAL, except you'll
omit <option>-ofps 23.976</option> (because the output framerate is the
same as the input framerate), and of course the crop dimensions will be
different.
</para>
<para>
After running <option>mplayer dvd://1</option>, we follow the process
detailed in the section <link linkend="menc-feat-telecine">How to deal
with telecine and interlacing in NTSC DVDs</link> and discover that it's
24 fps progressive video, which means that we needn't use an inverse
telecine filter, such as <option>pullup</option> or
<option>filmdint</option>.
</para>
<para>
Next, we want to determine the appropriate crop rectangle, so we use the
cropdetect filter:
<screen>mplayer dvd://1 -vf cropdetect</screen>
Make sure you seek to a fully filled frame (such as a bright scene), and
you'll see in <application>MPlayer</application>'s console output:
<screen>crop area: X: 0..719 Y: 57..419 (-vf crop=720:362:0:58)</screen>
We then play the movie back with this filter to test its correctness:
<screen>mplayer dvd://1 -vf crop=720:362:0:58</screen>
And we see that it looks perfectly fine. Next, we ensure the width and
height are a multiple of 16. The width is fine, however the height is
not. Since we didn't fail 7th grade math, we know that the nearest
multiple of 16 lower than 362 is 352.
</para>
<para>
We could just use <option>crop=720:352:0:58</option>, but it'd be nice
to take a little off the top and a little off the bottom so that we
retain the center. We've shrunk the height by 10 pixels, but we don't
want to increase the y-offset by 5-pixels since that's an odd number and
will adversely affect quality. Instead, we'll increase the y-offset by
4 pixels:
<screen>mplayer dvd://1 -vf crop=720:352:0:62</screen>
Another reason to shave pixels from both the top and the bottom is that we
ensure we've eliminated any half-black pixels if they exist. Note that if
your video is telecined, make sure the <option>pullup</option> filter (or
whichever inverse telecine filter you decide to use) appears in the filter
chain before you crop. If it is interlaced, deinterlace before cropping.
(If you choose to preserve the interlaced video, then make sure your
vertical crop offset is a multiple of 4.)
</para>
<para>
If you're really concerned about losing those 10 pixels, you might
prefer instead to scale the dimensions down to the nearest multiple of 16.
The filter chain would look like:
<screen>-vf crop=720:362:0:58,scale=720:352</screen>
Scaling the video down like this will mean that some small amount of
detail is lost, though it probably won't be perceptible. Scaling up will
result in lower quality (unless you increase the bitrate). Cropping
discards those pixels altogether. It's a tradeoff that you'll want to
consider for each circumstance. For example, if the DVD video was made
for television, you might want to avoid vertical scaling, since the line
sampling corresponds to the way the content was originally recorded.
</para>
<para>
On inspection, we see that our movie has a fair bit of action and high
amounts of detail, so we pick 2400Kbit for our bitrate.
</para>
<para>
We're now ready to do the 2-pass encode. Pass 1:
<screen>mencoder dvd://1 -ofps 23.976 -oac copy -vf crop=720:352:0:62,hqdn3d=2:1:2 -ovc lavc \
-lavcopts vcodec=mpeg4:vbitrate=2400:v4mv:mbd=2:trell:cmp=3:subcmp=3:mbcmp=3:autoaspect:vpass=1 \
-o Harry_Potter_2.avi</screen>
And pass 2 is the same, except that we specify <option>vpass=2</option>:
<screen>mencoder dvd://1 -ofps 23.976 -oac copy -vf crop=720:352:0:62,hqdn3d=2:1:2 -ovc lavc \
-lavcopts vcodec=mpeg4:vbitrate=2400:v4mv:mbd=2:trell:cmp=3:subcmp=3:mbcmp=3:autoaspect:vpass=2 \
-o Harry_Potter_2.avi</screen>
</para>
<para>
The options <option>v4mv:mbd=2:trell</option> will greatly increase the
quality at the expense of encoding time. There's little reason to leave
these options out when the primary goal is quality. The options
<option>cmp=3:subcmp=3:mbcmp=3</option> select a comparison function that
yields higher quality than the defaults. You might try experimenting with
this parameter (refer to the man page for the possible values) as
different functions can have a large impact on quality depending on the
source material. For example, if you find
<systemitem class="library">libavcodec</systemitem> produces too much
blocky artifacting, you could try selecting the experimental NSSE as
comparison function via <option>*cmp=10</option>.
</para>
<para>
For this movie, the resulting AVI will be 138 minutes long and nearly
3GB. And because you said that file size doesn't matter, this is a
perfectly acceptable size. However, if you had wanted it smaller, you
could try a lower bitrate. Increasing bitrates have diminishing
returns, so while we might clearly see an improvement from 1800Kbit to
2000Kbit, it might not be so noticeable above 2000Kbit. Feel
free to experiment until you're happy.
</para>
<para>
Because we passed the source video through a denoise filter, you may want
to add some of it back during playback. This, along with the
<option>spp</option> post-processing filter, drastically improves the
perception of quality and helps eliminate blocky artifacts in the video.
With <application>MPlayer</application>'s <option>autoq</option> option,
you can vary the amount of post-processing done by the spp filter
depending on available CPU. Also, at this point, you may want to apply
gamma and/or color correction to best suit your display. For example:
<screen>mplayer Harry_Potter_2.avi -vf spp,noise=9ah:5ah,eq2=1.2 -autoq 3</screen>
</para>
</sect2>
@ -775,7 +1009,7 @@ Notes:
quality is not within the scope of this document.
</para></listitem>
<listitem><para>
There are a couple footnotes specific to this guide, linked like this:
There are a couple footnotes specific to this guide, linked like this:
<link linkend="menc-feat-telecine-footnotes">[1]</link>
</para></listitem>
</itemizedlist>
@ -994,7 +1228,7 @@ Notes:
<screen>mencoder dvd://1 -nosound -ovc lavc -lavcopts ildct:ilme:mbd=2</screen>
</para></listitem>
<listitem><para>
<listitem><para>
Use a deinterlacing filter before encoding. There are several of
these filters available to choose from, each with its own advantages
and disadvantages. Consult <option>mplayer -pphelp</option> to see
@ -1027,13 +1261,13 @@ Notes:
use this method, then Reference the manual, and chose whichever
option looks best for your material. Note that when using
<option>tfields</option> you
<emphasis role="bold">have to</emphasis> specify both
<emphasis role="bold">have to</emphasis> specify both
<option>-fps</option> and <option>-ofps</option> to be twice the
framerate of your original source.
<screen>mencoder dvd://1 -nosound -vf tfields=2 -ovc lavc -fps 59.94 -ofps 59.94</screen>
</para></listitem>
<listitem><para>
<listitem><para>
If you plan on downscaling dramatically, you can excise and encode
only one of the two fields. Of course, you'll lose half the vertical
resolution, but if you plan on downscaling to at most 1/2 of the
@ -1159,7 +1393,7 @@ Notes:
59.94 fields per second, so the duplicate frames don't stand out as
much.
</para>
<para>
Either way, it's best to consider your content and how you intend to
display it. If your video is 90% progressive and you never intend to
@ -1168,7 +1402,7 @@ Notes:
interlaced.
</para>
</listitem>
<listitem><para>
Treat it as interlaced. Some frames of the progressive parts will
need to be duplicated, resulting in uneven jumpiness. Again,