The programs I used are as follows:

• dvdbackup (optional)
• xine (optional; only for cracking CSS)
• lsdvd
• transcode, mostly tcextract
• subtitleripper, for subtitle2vobsub
• ogmtools, for dvdxchap
• mkvtoolnix, for mkvmerge
• mplayer, for most of the stream dumping

Some Background

I don't know all the details of how data is stored on DVDs, but here's a rough overview. The video on DVDs is encoded in either MPEG-2 or MPEG-1 with a variable bit rate. The audio can be in raw PCM, DTS, MP2, or AC3. Most DVDs use AC3. Not all DVD players support DTS. Subtitles are stored as bitmaps with associated timecodes governing when to show them on screen.

In a DVD, the basic unit of video is a title. Each title consists of one or more video streams, zero or more audio streams, zero or more subtitle streams, and a list of timepoints to mark chapter boundaries. The titles on a DVD are grouped together into titlesets. All of the data for each titleset is concatenated together into VOB format and then split into 1GB chunks. The net result is that there's no one-to-one correspondence between files on the DVD and individual titles.

If a title has more than one video stream, one will be the primary stream while the others represent alternate angles. Few DVDs have multiple angles, so I'm not sure how the data for those works; all of the DVDs I've seen just have a single video stream for each title.

Also note that not all of the titles on a DVD are the feature content. Practically everything displayed by a DVD, including the splash image, copyright warning, ads and trailers, and even the menus is a DVD title.

Any of a DVD's titles may be encrypted with CSS. Either the DVD player or the DVD drive must have a licensed CSS decryption key in order to read the encrypted data. Fortunately, CSS is somewhat weak, and most Linux programs for accessing DVDs use libdvdcss to bypass the encryption.

Ripping the DVD

Ripping the DVD isn't strictly necessary, but it helps to have all of the data on your hard drive for processing. Even if you don't copy the videos to your hard drive, you'll have to mount the DVD and use its IFO files; I'll get to that later.

The easiest way to rip the DVD is with dvdbackup. It creates a directory for the DVD and then puts a VIDEO_TS subdirectory in the DVD directory. The VIDEO_TS directory contains all of the files in the DVD's VIDEO_TS directory. (Or, at least, it will if you use the -M option; other options give more restricted results.)

dest_dir=<destination directory>
dvd_name=<DVD name>
dvd_device=<DVD device, e.g. /dev/dvd>
dvdbackup -M -i $dvd_device -o $dest_dir -n $dvd_name

In theory, you could also mount the DVD and just copy all of the files over, but that has not worked well for me in the past, partly because of CSS problems, but also partly because my drive is a little wonky.

You can also just take an image of the DVD with dd. You'll need to disable the CSS beforehand. I've found that just running xine on the DVD is sufficient.

dest_dir=<destination directory>
dvd_name=<DVD name>
dvd_device=<DVD device, e.g. /dev/dvd>
xine dvd://
dd if=${dvd_device} bs=2048 conv=sync,noerror of=${dest_dir}/${dvd_name}.iso

If you have pv installed, you can get a fancy progress bar.

dest_dir=<destination directory>
dvd_name=<DVD name>
dvd_device=<DVD device, e.g. /dev/dvd>
xine dvd://
dd if=${dvd_device} bs=2048 conv=sync,noerror |
  pv -s $(fdisk -l $dvd_device |
          perl -nle 'm{^Disk '${dvd_device}': \d+ MB, (\d+) bytes$} and print $1') \
  >${dest_dir}/${dvd_name}.iso

Get Disc Info

Whether you've ripped the DVD to disk or not, you need to see what's on it. Change into your working directory and run lsdvd. (NB: From here on out, unless otherwise noted, all commands that reference a DVD will work equally well with a device (e.g. /dev/dvd), a disc image (like the one created with dd), or a directory containing a VIDEO_TS directory structure.)

dvd=<DVD device, image, or directory>
lsdvd -a -n -c -s -v $dvd > contents

Rip Each Title

The first order of business is to get the title data off of the DVD. mplayer's -dumpstream option will pull just the given title's stream out of the DVD. (Note that the resulting file has the possibility of exceeding 7GB in size; make sure your filesystem can handle files that large.)

title=<title number, e.g. 01>
dvd=<DVD device, image, or directory>
mplayer dvd://${title} -dvd-device $dvd -dumpstream -dumpfile ${title}.vob

The information about the title's chapters isn't in the VOB, so you'll have to extract that separately with dvdxchap. In my experience, dvdxchap never gets useful information for the chapter names (perhaps the DVD only contains the timepoints with no names associated), so you may want to edit the resulting file to put in more meaningful names. (Note that mplayer will output chapter information if you use its -identify option, but dvdxchap is more precise in its timing and also generates the data in the format that mkvmerge wants.)

dvdxchap -t $title $dvd > ${title}.chapters

I've seen DVDs where the TOC info as reported by lsdvd doesn't match the actual streams in the titles, so it's good to check the track directly with mplayer. mplayer gives audio stream ids in decimal, not hex, so the first audio stream will show as 128, not 0x80. It numbers the subtitle streams from zero, though, so you have to add 0x20 to the numbers it gives to get the actual subtitle stream ids.

mplayer -dvd-device $dvd -vo null -ao null -frames 0 -v dvd://${title} 2>&1 | egrep '[as]id' > ${title}.streams

In an ideal world, mkvmerge would be able to operate directly on the VOB, but when I tried that, it had problems demuxing the data and it died halfway through. So I'll use mplayer to pull out the individual components. Video first.

mplayer ${title}.vob -dumpvideo -dumpfile ${title}.video.m2v

Next up are the audio tracks. The VOB may contain more than one audio track. They should be labeled as to to their language, but check mplayer's info, not lsdvd's. mplayer's info will also tell what format the audio is in. mplayer will accept the audio stream ids in either decimal or hex.

lang=<language code>
track=<source audio track: 128, 129, 0x80, 0x81, etc.>
format=<extension for audio format; e.g. ac3, mp2>
mplayer ${title}.vob -aid $audio_track -dumpaudio -dumpfile ${title}.audio-${lang}.${format}

The VOB also contains subtitles, although most programs that query it won't see them. I tried using mplayer's -dumpsub command to get the subtitles, but it didn't work properly for me. So we'll just use the info from mplayer to get the language and stream id for each stream, but then use transcode's tcextract to actually pull the data out. Remember to add 0x20 to mplayer's stream ids. Some of the information for subtitles is stored in .IFO files on the DVD. Each titleset has its own .IFO file; check the contents file to see what titleset contains the track and use that titleset's .IFO file. It will be in the VIDEO_TS directory, named VTS_<titleset number>_0.IFO.

Matroska supports several subtitle formats, but VobSub is probably the easiest to use, because it's a series of bitmaps, just like the DVD subtitles. If you're not happy with VobSub, you'll need to OCR each image to get its text; there are instructions for doing so elsewhere on the Internet.

lang=<language code>
stream_id=<id of the subtitle stream>
ifo=<IFO file; e.g. /path/to/VIDEO_TS/VTS_nn_0.IFO>
<${title}.vob tcextract -t vob -x ps1 -a $stream_id >${title}.subs-${lang}.raw
subtitle2vobsub -p ${title}.subs-${lang}.raw -i $ifo -o ${title}.subs-${lang}

Finally, it's time to bring everything together with mkvmerge. When I use <title>, I mean the actual textual title for the video, like "Bob's House of Horror 2" or whatever. ${title} still refers to the title number on the DVD.

mkvmerge -o <final filename> \
         --title <title> \
         --chapters ${title}.chapters \
         ${title}.video.mpg \
         <audio clauses> \
         <subtitle clauses>

For each audio file, you'll need a clause giving the file and its language. The first file you list on the command line will be the default audio, unless you use mkvmerge's --default-track option to change it.

--language 0:${lang} ${title}.audio-${lang}.ac3

Likewise, you'll need a clause for each subtitle file. Since I generally don't want any subtitles displayed by default, I set things so that there isn't a default subtitle track.

--language 0:${lang} --default-track 0:0 ${title}.subs-${lang}.idx

And that should do it. After a fair bit of disk-churning, you should have a Matroska file containing all of the elements from the original DVD title. You can now delete all of your intermediate files and just keep the MKV on your computer and the DVD in its box.

I have a Treo 650. It has Bluetooth. I also have a USB Bluetooth Adapter. I originally planned to carry the bluetooth adapter around and hook it up to different computers whenever I wanted to talk to the Treo, but I've only been using it at work, so I've been leaving the adapter connected to my Linux computer at work. The thought occurred to me that I could use the Bluetooth adapter to see whether my phone was nearby and do things based on that information. At least to start, I decided to have the computer lock itself when I wasn't around.

I have the BlueZ Bluetooth stack installed. (On Debian, that's the bluez-utils package.) They include a l2ping program, but that establishes a full Bluetooth connection with the device, which makes my Treo turn on the screen, play a little sound, and show a pop-up dialog. That's a little intrusive for something that I want checked several times a minute. Some people use hcitool rssi to find out the strength of the phone's (or other device's) Bluetooth signal. That also requires a full Bluetooth connection. I ended up using hcitool name, which returns the name of the device if it's found and nothing if it's not. More importantly, it doesn't cause the Treo to do anything but silently send its response, and it works even if the Treo screen is off.

So I now have a stupid little shell script that looks like this:

#!/bin/sh

PHONE_ADDR=01:23:45:67:89:AB
PHONE_NAME="glamdring"
WAIT_TIME=15

while true; do
  if [ "$(hcitool name $PHONE_ADDR)" \!= "$PHONE_NAME" ]; then
    xscreensaver-command -lock
  fi
  sleep $WAIT_TIME
done

There are programs for Windows that do similar things. Possibly one of the simplest is Blue Lock, which is also open-source (and written in Delphi). I'm probably just going to write a simple Windows program to listen on the network for a message from my Linux computer to tell it to lock the screen.

How free is their speech? Read their Abuse page:

"A NearlyFreeSpeech.NET member site is defaming me or otherwise injuring me civilly."

Please forward a copy of your legal finding from a court of competent jurisdiction to our contact address. If you have not yet obtained such a finding, a preliminary injunction or court order is also sufficient.

If you are not able to obtain the above, you will need to work directly with the site operator to resolve your differences. We will have to fall back on our members' contractual assertion that the content they upload is legitimate and therefore we will not be able to get involved

How affordable is their hosting? You pay only for the bandwidth and storage that you actually use: $1 per gigabyte of bandwidth and $0.01 per megabyte-month of storage. (Plus the bandwidth cost goes down the more you use.)

They support a variety of CGI scripting languages, including C, PHP, Perl, Python, and Ruby. Oh, but also Fortran, Tcl, Lisp, Scheme, OCaml, and Haskell.

We'll see how it goes, but I think I'll like it here.

I'm working on a project for the class where I have to accept input in several different units of heat (BTUs, calories, and joules) and output the measurement in joules. I've made an abstract base class for the various units and created concrete classes for each unit the program has to read. I'd like to just have a list of available classes and have my program enumerate them automatically (rather than hardcoding the behavior for each), but the way I would normally think about doing this is painful in Java.

In Delphi, I'd do something like this:

type
  THeatUnits = class
   public
    constructor Create(Value : Real); virtual;
    class function GetUnitsName : String; virtual; abstract;
    function ConvertToJoules : Real; virtual; abstract;
  end;

  THeatUnitsClass = class of THeatUnits;

  TBTUs = class(THeatUnits);
  TCalories = class(THeatUnits);
  TJoules = class(THeatUnits);

const
  availableUnits : array [1..3] of THeatUnitsClass
                 = (TBTUs, TCalories, TJoules);

...

procedure DoStuff(Index : Integer; Value : Real);
  var
    Units : THeatUnits;
begin
  Units := availableUnits[Index].Create(Value);
  // Now do things polymorphically with Units.
end;

Delphi's class types often seem like a quick hack to me, but they beat what Java does in the same situation. For one thing, there doesn't seem to really be a class type in the same way that Delphi does it. There are instead objects of type Class. As far as I can tell, the best way to get one of those is to call Class.forName("ClassName"). But the painful part is that there's no specialization of class types at compile time, so the Java code equivalent to my Units := availableUnits[Index].Create(Value); above would be something like this:

static final AVAILABLE_UNITS = new String[] ("BTUs", "Calories", "Joules");

public void doStuff(int index, double value) {
  Class unitClass = Class.forName(AVAILABLE_UNITS[index]);
  Constructor unitConstructor = unitClass.getConstructor(new Class[] (double.class));
  HeatUnits units = (HeatUnits)unitConstructor.newInstance(new Object[] (new Double(value)));
  // now do things polymorphically with units.
}

(Common Lisp, of course, would be more succinct than Delphi, because everything is first-class; I would probably do something like this:

(defclass heat-units () ())

(defgeneric get-units-name (unit-class))
(defgeneric convert-to-joules (unit-class))

(defclass btus (heat-units) ())
(defclass calories (heat-units) ())
(defclass joules (heat-units) ())

(defparameter +available-units+ #(btus calories joules))

(defun do-stuff (index value)
  (let ((units (make-instance (svref +available-units+ index)
                              :value value)))
    ;; Now do things polymorphically with units.
    ))

)

As I said, though, I think this is just an artifact of not thinking in Java to the appropriate degree. Most of Java's reflection stuff seems set up to be useful at run-time while Delphi's run-time reflection is much uglier than Java's. And I think I'm going to approach my Java problem from a different direction, with an enum and a factory method. I was still struck by how annoyingly wordy (and not entirely typesafe) my first approach turned out to be in Java.

• 2 eggs, slightly beaten
• 1-3/4 cups pumpkin puree (1 can)
• 3/4 cup sugar
• 1/2 teaspoon salt
• 1 teaspoon cinnamon
• 1/2 teaspoon ground ginger
• 1/4 teaspoon ground cloves
• 1-2/3 cups evaporated milk (1 12-oz can)
• 1 9" pie crust, unbaked

Preheat oven to 425°F. Mix all ingredients. Pour into pie crust. Bake at 425°F for 15 minutes, then reduce temperature to 350°F and bake for 45 more minutes or until a toothpick inserted in center comes out clean.

• 3-4 lb. potatoes
• 4 eggs
• 1 medium white onion, diced
• mayonnaise
• pickle juice
• curry powder
• salt
• pepper
• yellow mustard
• paprika

Scrub and boil the potatoes. Hard boil the eggs. When the potatoes are done, let them cool then peel them--the skins should rub right off. Cut the potatoes into roughly 1" pieces. Dice the eggs. Mix together potatoes, eggs, and onion.

In a separate bowl, mix the mayonnaise and pickle juice until the mixture is the right consistency. Add the curry powder, salt, pepper, and mustard to taste.

Mix the dressing with the potatoes, then sprinkle paprika over the salad.

• 2 cups milk
• 4-6 tablespoons sugar
• 1 teaspoon salt
• 8 tablespoons butter (one stick), divided
• 2 packets yeast
• flour

In a small saucepan, mix the milk with the sugar, salt, and 6 tablespoons of butter. Heat to just below a boil, then allow to cool to room temperature.

Proof the yeast in some water with a little sugar. Mix the yeast into the milk, then add enough flour to get the right consistency.

Knead the bread, then allow it to rise until doubled in size, about an hour.

Preheat the oven to 375°F.

Melt the remaining 2 tablespoons of butter. Flatten the dough, then roll it out to about 1/4" thick. Cut circles in the dough with a biscuit cutter or the opening of a glass. For each circle, dip half of one side in the butter, then fold it in half with the butter on the inside. Place the rolls on baking sheets and allow to raise until increased in size by roughly 50%.

Bake at 375°F until done, roughly 8-10 minutes.