Maemo icon sizes

I had a hard time finding out which icon sizes one has to provide and where to install them for Maemo applications (I'm currently developing for OS2008 "chinook", might be different for other releases). Here is what I found out by looking at the contents of other GUI packages:

26x26 icon goes to /usr/share/icons/26x26/hildon/appname.png
40x40 icon goes to /usr/share/icons/40x40/hilson/appname.png
64x64 icon goes to /usr/share/icons/scalable/hildon/appname.png

The 64x64 icon will be used in the menu, so be sure to make it really 64x64, otherwise the icon will look out of place in the menu. Also, be sure to create an executable "postinst" file in the "debian/" subdirectory of your package source that has at least the following two commands:

gtk-update-icon-cache -f /usr/share/icons/hicolor
maemo-select-menu-location appname.desktop

Where of course "appname" is the name of your application and how you named your icon and .desktop file.

Fixing Macbook problems

Today, I've set out to fix some problems and annoyances that I had with my MacBook (August 2006) for several months:

• Suspend-to-RAM not working
• CD-ROM drive works unreliably (hda: drive appears confused)
  
• Newer kernels don't boot ("NMI appears to be stuck (0->0)!")
• Random lock-ups when VT switching from Xorg to text console

Kernel command-line parameters
I figured some of these problems were related to having obsolete/old kernel command line parameters that were needed for older 2.6 kernels to get things working, but are not needed for recent kernels. I'm currently using Debian's stock 2.6.22-2-686 kernel. The "append=" line in my /etc/lilo.conf for the kernel was "noapic acpi=force irqpoll resume=/dev/sda4". Removing the "noapic" option fixed the "NMI appears to be stuck" problem. Additionally, removing the "irqpoll" option fixed the CD-ROM drive problem ("drive appears confused"). Now, I can boot newer (2.6.22) kernels and have a working CD-ROM drive again (previously, the CD-ROM drive spontaneously "detected" an inserted Audio CD when there really was no CD inserted).

Compiz Fusion/Beryl and the intel driver bug
I've been running Compiz Fusion (and previously Beryl) and it worked great, except that when VT switching to the text console, the whole Macbook locked up sometimes. This bug is described in bug #127101 on Launchpad.net. So, I have now disabled the whole Compiz Fusion stuff and things seem to be working fine now, I have not yet had a random lock-up and garbled screen since. Sure, Metacity is not as nice as Compiz Fusion, and some Compiz features are really useful (Scale plug-in and Expo plug-in among some others), but it's better to have reliable shutdown than some Desktop bling-bling. With this text VT switch bug fixed, I've tried Suspend-to-RAM, which also seems to work okay-ish now. That would make Linux (Debian) awesome on that Apple MacBook :)

Hauppauge WinTV Nova-T Stick under Linux

I just got myself a Hauppauge WinTV Nova-T Stick (USB) and tried to get it working in Linux. With a bit of fiddling, I've got everything working, and also found an application to extract EPG info that can be displayed with OnTV.

First of all, you need to get the correct firmware. The file you need should be in the "dmesg" output after plugging in the stick. For me, the firmware file I needed was dvb-usb-dib0700-01.fw, so I googled around for it, found it and placed it in /lib/firmware/. After re-connecting the stick, the "dmesg" output should tell you that the firmware has been loaded. To get a working list of channels, I used w_scan with the "-X" parameter to generate a channels.conf.

Then, I downloaded xine (actually, I installed xine-ui in Debian) and placed the previously-generated channels.conf into ~/.xine/. This should already make things working: Start up xine, select "DVB" and wait for the channel to load. I had to change my window manager from Compiz to Metacity to prevent some errors related to the video stuff. With Metacity as window manager and xine, I get very good and performant video.

For EPG/XMLTV, I checked out the current Subversion trunk head of tv_grab_dvb. Compile it. To get the EPG data, you can't just simply tv_grab_dvb (or you can, but you would have to tune in somehow, which I didn't figure out). I solved this problem by simply running xine and watching TV, which tunes in into the right station, then running "tv_grab_dvb -e utf-8 -t 2 > ~/tv-guide.xml". This should result in a nice XMLTV file that can be parsed by other applications to give you EPG info. You can load this file into OnTV and have an EPG. To get OnTV for Debian, I downloaded the Ubuntu source package for "ontv" and compiled it on Debian. Then, add "OnTV" to your gnome-panel and configure it with the XMLTV you generated above. Then, select the TV channels to monitor and click on the TV icon. You should see the list of current programs.

So, DVB-T on Linux works fine with the Hauppauge WinTV Nova-T Stick. Neat!

Update: The stick was only for testing compatibility on Linux, I don't use it anymore. Please see the Linux TV websites for more information.