- RaspberryPi Notes
- Installing the precompiled package
- Compiling libavg from source
This is outdated. There are current cross-compile instructions at RaspberryPISourceInstall
These are temporary notes on how to get libavg running on a Raspberry Pi. The easy way is to simply install the precompiled package, but this might not always be up-to-date. Alternatively, you can also compile libavg yourself.
Installing the precompiled package¶
We have a tarball that you can copy to /usr/local to install libavg for now. The tarball is just a build of an svn snapshot and thus beta, but passes all but a few minor tests. To get this running, install the dependencies first:
$ sudo apt-get install libxml2 libpango1.0-0 librsvg2-2 libgdk-pixbuf2.0-0 \ libavcodec53 libavformat53 libswscale2 libboost-python1.49.0 \ libboost-thread1.49.0 libsdl1.2debian libxxf86vm1
Then, download libavg-raspberry.tar.bz2 and unpack it to /usr/local:
$ tar -C /usr/local -xjf libavg-raspberry.tar.bz2
Compiling libavg from source¶
libavg needs to be compiled on a separate machine because the Raspberry would a) take hours to do it and b) gives up with an out of memory error before it's done. So we take a stock Raspberry disk image, mount it on the host computer, install libavg prerequisites there and compile in a chroot environment. This is not nearly as complicated as it sounds and gives you compile times of about 20 mins for a complete compile on a modern computer.
The procedure described below has been tested under Ubuntu 12.04 LTS, but should work with other releases/distros, too. QEMU version >= 1.0 is required.
Command lines starting with a "
$" are executed on the x-build host system, lines starting with "
#" inside QEMU or the chroot environment.
Install QEMU (from universe repository)¶
$ sudo apt-get install qemu qemu-user-static qemu-system
Download raspbian wheezy image¶
Download the image from http://www.raspberrypi.org/downloads/. The hard float one is the image we want.
$ unzip 2013-09-10-wheezy-raspbian.zip
Create larger root file system image, copy data to image¶
As-is, the file system image downloaded doesn't have enough free space, so we copy the data to a new, larger image.
$ qemu-img create wheezy-raspbian-devel.ext3 4G $ mkfs.ext3 wheezy-raspbian-devel.ext3 $ mkdir rootfs tmp $ sudo mount wheezy-raspbian-devel.ext3 rootfs/ -t ext3 -o loop $ sudo mount 2013-09-10-wheezy-raspbian.img tmp/ -o loop,offset=$[122880*512] $ sudo cp -a tmp/* rootfs/ $ sudo cp /usr/bin/qemu-arm-static rootfs/usr/bin/ $ sudo umount tmp $ rmdir tmp
Note: All raspbian images newer than
2012-12-16-wheezy-raspbian don't work with QEMU without a minor tweak: Before unmounting
rootfs/etc/ld.so.preload and comment out the single line it contains. Older images can be found at http://mirrors.arizona.edu/raspberrypi/images/raspbian/.
Download linux kernel¶
$ wget http://xecdesign.com/downloads/linux-qemu/kernel-qemu
Start emulation, prepare libavg build:¶
Always unmount image before starting QEMU! If you forget this, you will very likely have a trashed image and need to start over again.
$ sudo umount rootfs $ qemu-system-arm -kernel kernel-qemu -cpu arm1176 -m 256 -M versatilepb -serial stdio -append "root=/dev/sda panic=1" -hda wheezy-raspbian-devel.ext3 -clock dynticks
Emulation starts, drops to maintenance shell because of wrong file system mount time (on 1st boot only). Do a file system check:
# fsck.ext3 /dev/sda # reboot
In qemu emulation
# sudo apt-get update # sudo apt-get install subversion automake autoconf libtool libxml2-dev \ libpango1.0-dev librsvg2-dev libgdk-pixbuf2.0-dev libavcodec-dev libavformat-dev \ libswscale-dev python-dev libboost-python-dev libboost-thread-dev g++ libSDL-dev \ libxxf86vm-dev linux-libc-dev
Checkout libavg (still in qemu)
# cd /home/pi/ # mkdir -p devel/libavg # cd devel/libavg/ # git clone https://github.com/libavg/libavg.git
Stop the emulation.
Chroot, x-compile libavg¶
Make sure the emulation is stopped, then:
$ sudo mount wheezy-raspbian-devel.ext3 rootfs/ -t ext3 -o loop $ sudo chroot rootfs/ # export LANG=en_GB.utf8 # cd /home/pi/devel/libavg/libavg # ./bootstrap # ./configure --enable-rpi --prefix=/home/pi/devel/libavg/install # make -j9 # make install
For some QEMU configurations
chroot fails to start
bash with a xmalloc error ("cannot allocate x bytes"). To remedy this, run:
$ sudo chroot rootfs/ /bin/sh # QEMU_RESERVED_VA=0 bash
Move the compiled libavg to the Raspberry¶
make install, there is a tree of files in
devel/libavg/install that can be copied to
/usr/local/ on the Raspberry. Rename
dist-packages. For the uninstalled version (e.g. to run
src/test/Test.py), copy devel/libavg/libavg to the raspberry.
I use this simple script for the task:
#!/bin/bash cd devel/libavg/install/lib/python2.7 sudo rm -rf dist-packages sudo mv -T site-packages/ dist-packages cd ../.. scp -r * email@example.com:/usr/local
Further development / testing notes¶
To get rid of ALSA sound buffer underruns, change avgrc: