Marcus Hellberg » Software

Textile to XHTML converter

admin — Fri, 22 Jan 2010 11:42:07 +0000

A while back, I needed to quickly write some documentation that needed to be in XHTML format. Writing in plain XHTML is a pain, so I decided to write the documentation in Textile and then convert it to XHTML before publishing.

The problem I found was that all Textile converters were made for use in blogs and other online tools. What I needed was a good old-fashioned command line program to convert a given textile file into XHTML.

Fortunately, using Ruby and the excellent RedCloth gem, I could write a small script to accomplish this in a few minutes.

If you have any similar needs, copy the source into a file named textile2html, make it executable (chmod +x) and place it somewhere in your path. Then all you have to do is call textile2html with the textile file as an argument:

$ textile2html documentation.textile

#!/usr/bin/env ruby -wKU
require "rubygems"
require "RedCloth"

if ARGV.size != 1
puts "Usage: textile2html file.textile"
exit
end

# Read input file
textile_string = ""
begin
  input_file = File.new(ARGV[0], "r")
  input_file.each do |line|
    textile_string+=line
  end
  input_file.close
rescue
  puts "Could not read input file."
  exit
end

# Create output file
filename = ARGV[0].gsub(/\.\w+$/, "")
begin
  output_file = File.new("#{filename}.html", "w")
rescue
  puts "Could not create output file."
  exit
end

html_header = <




DOC

html_header += filename;
html_header += <<DOC



DOC

html_footer = <

DOC

html_output = RedCloth.new(textile_string).to_html
output_file.puts(html_header)
output_file.puts(html_output)
output_file.puts(html_footer)
output_file.close

puts "Done."

Questions? Comments? Post them below.

Converting MKV files for the Xbox 360 or PS3 on a Mac

admin — Sun, 03 Jan 2010 17:52:56 +0000

I use my Xbox 360 for most of my media viewing in the living room. This can sometimes be a hassle since I’m using a Mac, and Microsoft hasn’t exactly made it easy to share media from a mac to an Xbox 306. I use a third party program, Connect360, that easily allows me share media from my computer to my Xbox. In reality, though, the Xbox fails to find my Mac about 75% of the time.

What is more annoying, is that the Xbox 360 doesn’t play Matroska Video containers, even though the video itself is encoded in h.264 or MPEG-4. There are several ways of playing the videos on the Xbox, but unfortunately all of them require converting the video.

HandBrake, previously only a DVD ripper, is an easy tool for converting videos. Unfortunately, HandBrake always transcodes the video, even though the video itself is in a format that is playable by the Xbox 360. This method will work, but the process is very time-consuming. On an upside, the program is free and works very well. Hopefully, they’ll add support for passing through the original video from the MKV container to a MPEG-4 video (m4v) container.

A better solution would be to only package the video in a new container that the Xbox 360 can understand. This process can be done with several tools. Using QuickTime Pro 7, you can export the file to another format passing though the video. You only need to re-encode the audio track, which makes this a much faster process than the Handbrake method. The QuickTime Player X bundled with Snow Leopard seems to have lost this functionality. It should be possible to install the older version of QuickTime, but the Pro license is pretty expensive if this is the only use you’ll have for it.

The easiest way I have found to do the conversion is by using MKVtools. This is a small program, specifically designed to do this task as easy as possible. It uses several open source tools to extract and re-encode the file and comes with presets both for the Xbox 360 and PlayStation 3. While it is possible to use the tools directly, MKVtools really takes the hassle out of the process. The best part is that the program is only $5 and has a fully functional trial.

The resulting mp4 or m4v file should play on the Xbox 360 or PS3 without a problem. The only downside is that you lose the multichannel soundtrack, and have to settle for stereo. For most programs, this really isn’t a big problem in my opinion.

Do you have any better ways of viewing MKV files on a Xbox 360 that I’m unaware of? Please post them in the comments!

My top free apps for Android

admin — Wed, 30 Dec 2009 13:38:00 +0000

Sure, there are a lot of top lists for Android applications. But there is not yet one for my top Android apps. So here are my top 5 (or so) applications for Android:

1. MyTracks

MyTracks is Google’s sports tracking software for Android, much like Nokia Sports Tracker is for S60 devices. With this application you can track your sporting (or other) routes and see statistics over your performance. The application lets you upload routes to Google maps and statistics to a Google Docs spreadsheet for easy analysis.

I really like this application as I bicycle a lot. Being able to measure routes and see average speeds, resting time vs moving time and other statistics really make working out more interesting (and geeky). It allows you to concentrate on the sports performance without having to worry about pausing the application every time you take a break for instance.

[Image courtesy of Google]

2. Fring

Even though I mostly use Google Talk on my HTC Hero, I occasionally need to contact people without Google Talk accounts. Fring is by far the best application I have found to do this on the Android platform. Fring lets you access contacts on pretty much any imaginable instant messaging network, like MSN, AOL, Yahoo, Skype, as well as its own Fring protocol. To make things even better, the application has support for making Skype calls over 3G and WLAN, which has come in handy while traveling.

[Image courtesy of Fring]

3. Google Maps

I want to mention Google Maps even though it comes with the phone. I use the application almost daily, looking up nearby services or routes to places. The Maps application on the HTC Hero lacks navigation, which would definitely place this application at the top of the list. Once you have gotten used to having a GPS in your pocket, there is no going back.

4. handyCalc

This is probably the best calculator I have found for Android. It allows you to do simple calculations easily, but also supports much more. For instance, it supports solving equations, plotting graphs and converting currency. This application is a must-have for anyone that has to do some more advanced math once in a while and doesn’t like lugging around a Texas Instruments calculator all the time.

5. ConnectBot

ConnectBot is a very handy SSH client for Android. It allows you to easily connect to SSH servers and perform maintenance tasks without having to bring along your laptop everywhere. Combined with the large screen of the Hero, this application is really useful.

[Image courtesy of ConnectBot]

6. Bebbled

The final application on this list is a game. The game is much like Bejewled, and easily as addicting. The major difference is that it supports turning around the device have the blocks move to the “ceiling.” This brings a new dimension to the game and makes it really addictive.

[Image courtesy of Bebbled]

What are your favorite Android Apps? Please share any apps that you have found useful in the comments.

Google wave invitation giveaway

admin — Wed, 23 Dec 2009 18:57:11 +0000

As a present to all readers, I’m handing out 17 invitations to Google Wave. All you have to do to get your invitation is to be among the 17 first non-spambot commenters in this post.

Update: There are still 11 invites left.

Digital TV in Linux

admin — Wed, 23 Dec 2009 18:23:39 +0000

Watching digital tv in Linux with em2880 devices

Note: This post is from my earlier site. I moved it over here because I see that a lot of people are trying to access it without finding it. It is written in 2007, so all content may not be up to date. You can report successes/failures in the comments so I know if it needs to be updated.

I found a really cheap refurbished Pinnacle PCTV USB DVB-T receiver in my local computer store and after googling to make sure it supported Linux I bought it. Here’s how I made it work in Linux.

The USB stick itself is fairly small, although it is just wide enough to block the other USB port on my laptop. It came with a small antenna with a magnetic stand and a tiny remote. The antenna is connected to the USB stick with a regular antenna connector, you can easily connect it to a better antenna if needed.

In this article I’ll show you how I first set up the drivers for the tuner, then setting up kaffeine for viewing TV and lastly configuring the remote. The steps should be fairly easy to follow if you’ve used the console before – if not, just copy n paste and you should be fine.

This article is about the Pinnacle PCTV USB Stick DVB-T receiver, but the same steps should work for any device using the em2880 driver. According to the em28xx wiki, these devices should also work:

Digital devices:

Pinnacle/800e|Pinnacle HD Pro Stick (North American version, NTSC/ATSC)
Kworld 350 U DVB-T
Kworld 310 U
MSI DigiVox A/D (USB2.0)
Hauppauge HVR 950 (NTSC/ATSC)
Hauppauge WinTV HVR 900 M/R: 65008/A1C0
Terratec Cinergy Hybrid T XS – ZL10353
Terratec Cinergy Hybrid T XS – MT352
Terratec Cinergy Hybrid T XS France
Terratec Prodigy Hybrid T XS
Terratec Cinergy T XS – xc3028
Terratec Cinergy T XS – mt2060
Pinnacle PCTV USB Stick
DNT DA2 Hybrid
Pinnacle PCTV Hybrid Pro Stick
Empire USB 2.0 Pen Dual TV
BestBuy Easy TV USB hybrid

Analog devices:

Usbgear VD204v9
Leadtek Winfast USB II deluxe
SIIG AVTuner-PVR
Prolink PlayTV USB 2.0
Terratec Cinergy 250 USB
Pinnacle PCTV USB 2
Hauppauge WinTV USB 2
MSI VOX USB 2.0
Pinnacle Dazzle DVC 90
Kworld PVR TV 2800 RF
Hercules Smart TV USB 2.0
MSI Movie Vox
D-Link DUB-T210 TV Tuner
Gadmei UTV 330
Gadmei UTV 310
Supertronindia Supercomp TV USB 2.0

Programs needed

You will need the following programs for this to work, we’ll install everything up front so we can concentrate on the more interesting stuff later.

a recent kernel with sources, 2.6.15 and newer should be fine (install kernel-sources in SuSE)
Hg from http://www.selenic.com/mercurial/ (in SuSE you should find a package named mercurial)
kaffeine with the xine engine (in SuSE, add packman and guru repositories and install kaffeine, libxine and libxine-dvb)
lineak with kde plugin (on SuSE, install lineakd, lineakd_kde and lineak_defaultplugin)
gcc compiler, is included on most distros by default
dvb package (dvb in SuSE)

For Ubuntu (Edgy) you’ll need the following packages:

All should be available from the default repositories, make sure to have the “Universe” repositories enabled (under System>Administration>Software Sources).

mercurial
gcc
build-essential
linux-source
linux-headers-`uname -r` (the linux headers for your specific kernel version)
kaffeine (version 0.8 or above. Other dvb watching applications will work as well but only kaffeine will be covered here)

Otherwise the install works the same as for SuSE.

Downloading and compiling the driver

Some users will need a firmware file to make their devices work, if you see your device listed here follow the directions, if not continue on to installing the driver.

These devices need firmware version 1:

Terratec Cinergy Hybrid T XS (french edition)
Terratec Cinergy T XS
DNT DA2 Hybrid
Kworld 350U

These devices need firmware version 2:

MSI DigiVox A/D
Kworld 310U
Terratec Cinergy Hybrid T XS (USB ID=0ccd:005e)

These devices need firmware version 3:

HVR 900 B2C0(sticker on the dev.)
HVR 900 A1C0
Terratec Cinergy Hybrid T XS
Pinnacle PCTV Hybrid Pro
Pinnacle PCTV Hybrid Pro Stick (320e) (USB ID=eb1a:2881)

These devices need firmware version 4:

Pinnacle HD Pro Stick (North American version, NTSC/ATSC)

These firmware files can be obtained from here.

IMPORTANT: Download the file into /lib/firmware, then extract them with “sudo tar zxvf filename.tar.gz”
Getting and installing the driver

Create a folder somewhere convenient.

mkdir driver

Now, go into that directory and type

hg clone http://mcentral.de/hg/~mrec/v4l-dvb-kernel

Which will download a copy of the driver sources to your directory.

Compiling the driver varies a bit depending on if you had to download the firmware or not. If you had to download it keep reading here, if not skip on to part b.

Compiling:

cd v4l-dvb-kernel/v4l
make
sudo make install

You now need to reboot (bookmark this page so you’ll find it again).

The fun part

Hi and welcome back, I hope the boot didn’t take too long.

If everything has gone well you should be a few short steps away from viewing tv on your computer.

We still need to load the driver we compiled earlier, as root type in the following.

modprobe em28xx

You shouldn’t get any messages, just be returned to the prompt.

Open up kaffeine either from the menu, or from the console by typing ‘kaffeine’. It should recognize that you

have a dvb adapter and ask you for some additional info.

Select your location and check that everything else is in order and then continue.

In kaffeine you have in the menu bar a DVB menu, select channels from that. Now just press scan and hope. If all went well you’ll soon start seeing all the channels that have been found. If you can’t find any channels its most likely because of the tiny little antenna that came with the tuner, either try going to some place with better reception, or plug the antenna cable to a roof-top antenna.

If you’re happy controlling your viewing with a mouse and keyboard, you’re done. If you want to get the remote to work as well stay with me for a little while longer.

Setting up the remote

The remote is just another input device to the system, just like the extra buttons on newer keyboards, so I decided to use lineak for the task.

I used xev to get the different key codes the buttons on the remote are sending, unfortunately not all of them sent anything. I don’t know if this is just something that’s wrong with my remote, or a “feature”.

Anyway, here is the section to that I added to /etc/lineakkb.def:

#### Pinnacle PCTV USB Stick Remote ####

[PCTV]

  brandname = "Pinnacle"

  modelname = "PCTV USB Stick Remote Control"

  [KEYS]

    Mute             = 160

    Record           = 177

    Power            = 222

    Rewind           = 152

    Stop             = 232

    Play|Pause       = 110

    Forward          = 233

    VolumeUp         = 176

    VolumeDown       = 174

  [END KEYS]

[END PCTV]

#### END Pinnacle PCTV USB Stick Remote ####

If you find the missing key codes, please leave a comment and I’ll update this.

Save the lineakkb.def file and as a regular user type:

lineakd -c PCTV

It will create a configuration file for your keyboard in ~/.lineak/ named lineakd.conf

In this file you can set up what you want all the buttons to do, below is a mine as a sample:

 # LinEAK - Linux support for Easy Access and Internet Keyboards

#  Copyright (c) 2001,2002, 2003

#     Sheldon Lee Wen  (Current Maintainer)

#      and Mark Smulders 

#  http://lineak.sourceforge.net

#

# lineakd configuration file

#

# example key configuration:

#     play    = "xmms --play-pause"

#     eject    = EAK_EJECT

#

# Lineakd supports the following modifier keys:

#    control alt shift mod2 mod3 mod4 mod5

CdromDevice = /dev/cdrom

Display_align = center

Display_color = 0aff00

Display_font = -adobe-helvetica-bold-r-normal-*-*-240-*-*-p-*-*-*

Display_hoffset = 0

Display_plugin = internal

Display_pos = bottom

Display_soffset = 1

Display_timeout = 3

Display_voffset = 50

KeyboardType = PCTV

MixerDevice = /dev/mixer

RAWCommands = 

Screensaver = 

conffilename = /home/marcus/.lineak/lineakd.conf

keystate_capslock = 

keystate_numlock = 

keystate_scrolllock = 

Forward = "dcop kaffeine KaffeineIface posPlus"

Mute = "KMIX_MUTE"

Play|Pause = "dcop kaffeine KaffeineIface pause"

Power = "kaffeine DVB"

Record = "dcop kaffeine KaffeineIface fullscreen"

Rewind = "dcop kaffeine KaffeineIface posMinus"

Stop = "dcop kaffeine KaffeineIface stop"

VolumeDown = "KMIX_VOLDOWN"

VolumeUp = "KMIX_VOLUP"

As you see, I had to put the record button to control full screen toggling, as I couldn’t get the key code for the real full screen button. Please check the lineak documentation for additional commands, as well as typing ‘dcop kaffeine KaffeineIface’ to get a list of all the commands you can send to kaffeine.

To start type

 lineakd&

To start lineak automatically with KDE make a symbolic link like this:

 ln -s /usr/bin/lineakd /home/marcus/.kde/Autostart/

So that’s it, now you should be able to enjoy your favorite tv shows on your computer and control it with the remote (although the effective distance on the remote is probably less than the length of your arm

References

The em28xx wiki check this wiki if you have any problems, they are probably solved there.

Lineak documentation

Google Nexus One rumors and walkthough

admin — Wed, 23 Dec 2009 11:02:46 +0000

Lately, there have been a huge buzz around the internet about Google starting to sell their own Android-based handset. Apparently, Google has given out phones, called Nexus One, to Google employees for internal testing before the launch. This has resulted in a lot of blurry pictures and descriptions of the new mystery device.

If this is a marketing stunt by Google, which I think it is, its very effective. The device certainly looks good.

Engadget had managed to get their hands on one of the devices and seemed to be very impressed. They noted that the Nexus One has: “… probably the best screen we’ve seen on a smartphone so far.” They were also impressed by the speed of the device, something that has been a major issue for most Android devices so far. Comparing browsing speeds they noted:

When comparing the three phones in loading a webpage over Wi-Fi, the Nexus One loaded first, the iPhone 3GS came in a few seconds later, and the Droid came in a little while after that. This was constant throughout many webpage loads, so it’s indicative of something going on inside with the hardware.

A video walkthough of the interface looks very promising. The interface moves quickly, and the screen seems very spacious compared to my HTC Hero.

The Nexus One is rumored to be sold without contract, for $199 or $99 for existing Google account holders. If this is true and Google sells the phone to Finland, I’m definitely getting one. The low price point seems too low to be true. If it is true, I’m sure that Google will have some ads and/or usage monitoring to recoup the hardware costs.

Reuters reported that the phone should go on sale directly from Google on January 5th. We’ll just have to wait until then and see which rumors are true.

WordPress LaTeX plugin

admin — Mon, 21 Dec 2009 09:25:48 +0000

Now that I have code highlighting working, I thought that I should still look into getting some easy way to display mathematical notation. Turns out that WordPress once again delivered, there are in fact several different LaTeX plugins available.

The plugin I settled for is WP LaTeX, since it allowed me to use wordpress.com’s LaTeX server. This was an easier alternative, as Dreamhost does not have dvipng installed. On a side note, I’m impressed that they have LaTeX installed by default.

Now I only have to insert the following to create a nice looking equation:

H(z) = \frac{1}{1-2 cos(2 \pi k / N) z^{-1} + z^{-2}}

Bonus points for anyone who can identify the transfer function

Transferring Gmail to Google Apps with own domain

admin — Sun, 20 Dec 2009 15:24:35 +0000

My hosting plan with Dreamhost had an option of using Google Apps with my own domain. In practice, what I wanted was using Gmail, only with my own domain in the address.

The process of setting up Google Apps with an own domain was straight forward. All I had to do was enable Google Apps for my domain in the Dreamhost admin interface and then sign up for a Google Apps account. I had to upload a HTML-file to the root of my domain to assure that I in fact own the domain.

The big problem I had was that I currently have a Google account that I use both for my HTC Hero and for Gmail. What I really wanted was to be able to migrate that account to my own domain. This was unfortunately not possible as the two accounts are entirely separate.

I could import all of my previous mails from Gmail to the new Gmail through POP, even though it was a big pain. I could also set my old Gmail to forward any new messages automatically to the new address.

I still decided to keep using my Gmail as my primary email address because it is most convenient. The new address will, at least for the time being, stay as a secondary email mainly for this site. It is still very convenient to have an email address with an own domain and still be able to use it from anywhere using the Gmail interface and 7+ GB of storage.

Short review of the Grooveshark Android application

admin — Sat, 19 Dec 2009 16:37:29 +0000

Grooveshark recently released a “sneak peak” of their Android app. The application had already been shown in the Android Developer Challenge, but it got finally released for the general public to use.

The application is still a “sneak peak,” so many of the bugs I found are surely already being worked on. The application only works for VIP Grooveshark users, so if you want to try it out, you have to pay $3 a month.

The app opens up with a splash screen with the same yellow-blue background as the Grooveshark flash player has by default. The splash screen lasts for quite a while, making sure that you notice that the application is still in alpha.

I have to admit that I like the interface of the app. I don’t have a rooted Android device, so I couldn’t take real screen shots, these will have to do for now:

As you can see, the interface is dark and, at least in my opinion, quite nice. The application is very rough still. The parsing of the search results seems to take very long. Also, since the first day I used the app, I haven’t been actually able to listen to music with it. This seems like a big problem still. The application has also other issues, like the splash screen being displayed every time the application is taken into the foreground. The application does not seem to start buffering the following track while playing the previous, so there is a long gap between songs.

So, it’s quite evident that the application is indeed a “sneak peek,” not a finished application. It does, however, show great potential for future versions. Like Spotify, it supports offline playlists. It also has the radio feature from the flash application enabled by default, which makes it ideal for just choosing a couple of songs and leaving in the pocket to play.

I’m eagerly awaiting an updates to the app, and will update this post with new impressions as the application is developed.

Why i moved from Spotify to Grooveshark

admin — Sat, 19 Dec 2009 14:56:45 +0000

I recently switched from using Spotify for Grooveshark.”Why?,” you may ask. Well let me tell you.

I have been using Spotify for quite a while, I got an invitation back in October of 2008. At first, I was very happy. The promise of cloud computing seemed to come to life, I had access to all the music I could ever hope to listen to. But gradually the service started degrading. Finally, last month I had enough and canceled my premium subscription and moved to grooveshark.

The thing that I liked most about Spotify in the beginning was the ability to easily access any music I wanted at a particular moment. If I was feeling indecisive, I could always choose a top-list and listen to that. Slowly the country restrictions started rolling in. At one moment I remember closing Spotify with an artist’s listing open. When I opened Spotify the following morning, all but one album had disappeared from the list.

To make matters worse, top lists would show all songs that I couldn’t listen to in pink. The real problem was, however, that the songs that weren’t allowed to be played in Finland seemed to be chosen arbitrarily from different versions of a song. For instance, if I clicked on an artist’s name in the list, I could choose another version of the song to listen to without problems.

So, not only did not Spotify’s country restrictions not work, but they also made my experience worse.

This fall I was happy that Spotify released an Android app, I immediately purchased Spotify premium to try it out. The first big hurdle was that the Spotify app wasn’t anywhere to be found in the Android market. As it turned out, Finland didn’t have, and still doesn’t have, an official Android Market. This isn’t in any way Spotify’s fault, it’s Google being slow in realizing that the world extends beyond the United States.

Sorry, got a bit sidetracked there. Anyway, the Android app was alright, but not really worth the 10€ a month it cost. The offline playlists were a welcome addition, as I often listen to music while bicycling and at times I’m not within HSPA coverage. The app was a bit buggy, stopping between tracks until the app was taken to the foreground again. This made it impractical while doing anything else since I had to take out the phone every once and again to resume the music.

When I decided that the Android app wasn’t worth paying for, I canceled my Spotify premium subscription. To my horror, I found out that during the two months I had been premium the amount of ads had exploded. Not only had the banners grown larger and more obnoxious, but the audio ads had introduced a bug that caused the next song to start from the time that the previous song had ended on. This meant that if I listened to a long song, Spotify would skip through half of my playlist until it started a commercial.

I finally had enough and decided to check out Grooveshark, a service I’d used on occasion before. The interface had gotten a radical improvement since my last try and I really liked it.

If you clicked the Grooveshark link, you probably already noticed the first advantage that Grooveshark holds against Spotify: a web-based interface. Now I could listen to my playlists anywhere, without having to install any software.

The player interface on Grooveshark is different than on Spotify. When searching for songs you can click on any song to start playing it. But instead of continuing with the next song in the list, you can drag and drop songs into the play queue on the bottom of the screen. The queue remains there across searches and is in my opinion a very nice way to organize my listening. When I’m satisfied with a queue, I can save it as a playlist.

Even better, if you get tired of selecting songs for your self, you can press the “radio” button and let Grooveshark continue your list with similar music. You can then like/dislike the suggested songs to teach Grooveshark what you like.

Grooveshark also released an Android application recently. But as this post is starting to get way too long already, I’ll do another post about that shortly. Stay tuned.