Wednesday, October 30, 2013

debian 8 for wandboard

debian 8 for wandboard

You can download the image using the following links (part1) (part2) (part4) (part3)
Thank you Martin for the great job.


ssh debian@ or ssh root@
password: debian (for both, “debian” and “root” users)

The running webservices can be accessed by doing :
Owncloud —>
Ampache —>
Aria2       —->
Webmin  —->
Phpmyadmin —>

fix for message in kernel on wandboard (silences it anyway)

 to get rid of messages about voltage changes


echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

Hello There,

I am using 12.04.2 LTS, and I keep getting this error on console "COULD NOT SET SOC VOLTAGE BACK!!!!", it is flooding the logs.

Any idea what it is, and how to stop?

Posts: 3
Joined: Thu Oct 03, 2013 6:49 am

Re: Keep getting error on console COULD NOT SET SOC VOLTAGE BACK

Postby Tapani on Thu Oct 03, 2013 9:19 am
An unfortunate "bug" in the kernel. It is not dangerous, just someone at freescale making unexpected behaviour sound worse than it is.

Try changing the scaling governor, that usually makes it quiet:
Code: Select all
echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

Saturday, October 26, 2013

ffmpeg transcode of h.264 and ac3 encoded files to play on more devices

many devices won't play ac3 coded media.  this a discussion of recoding

Its been done, and you don't even need to whitelist your chromecast, you just have to enable 'developer mode' in the Google Cast extension. The guy even made a VLC transcoding option, but I just quickly repackage my files with FFmpeg if needed before playback.

I would first use mediainfo to see what your file is already, and check against the list of supported codecs for the Chromecast.
Assuming that you do need to convert, you need to figure out what exactly. For example, a lot of scene(aka pirate) releases that are in MKV are H.264 video(which works just fine on the Chromecast) and AC3 audio(which does not work on the Chromecast). So in a lot of cases, you will just be repacking the audio.
Depending on your FFmpeg, you will have different encoding and decoding libraries. The most surefire way is to just build it yourself - but I think if you're on Ubunut you can install packages for encoders.
But generally, what I do is repack the video(no conversion), and convert the audio to either AAC(preferred), or MP3(a better fallback option if you're using Windows).
I do:

ffmpeg -i <input file> -c:v copy -c:a libfdk_aac <output file>
if converting to MP3 audio, you need to specify a specific bitrate:

ffmpeg -i <input file> -c:v copy -c:a libmp3lame -b:a 320k <output file>
And lastly, if you video didn't come in H.264 to begin with, go ahead and just re-encode like this:

ffmpeg -i <input file> -c:v libx264 -c:a libfdk_aac <output file>
Hope this helps!
Edit: If you convert from a non-H.264 file, the audio may already be in MP3, and then you would only need to convert the video, like so:

ffmpeg -i <input file> -c:v libx264 -c:a copy <output file>

chromecast discussion

comment in thread about vlc stream to

It's actually not very hard, since VLC already supports transcoding and streaming to a socket. I found a Java project that was experimenting with it, but I don't have the link available at the moment. I tested it out by running VLC like this:

vlc -Irc --sout="#transcode{vcodec=VP80,vb=1000,width=500,acodec=vorb,ab=128,audio-sync,channels=2,samplerate=44100}:http{mux=webm,dst=:8000/cast.webm}"
And then told my Chromecast to stream  
(you need to write a custom app for that part), and it mostly-worked. I was having problems with video/audio sync, but that might be something I did wrong, I didn't spend very long on it. I imagine once we can release apps somebody will write a simple one that takes a URL and tells the Chromecast to stream it, and that's really all you need

Friday, October 4, 2013

snow leopard on virtual box 4



1) VirtualBox 4
2) iBoot and Multibeast.
3) An ISO of Snow Leopard retail version.
4) The DMG of the latest (10.6.6) combo updater.

1) Make a new OSX Server image in Virtualbox, call it "OSX", use all the defaults except make a bigger disk than 20GB - 40GB is a better number.
2) Go to settings and untick the "Enable EFI setting" in the System pane.
3) Mount iBoot.iso and boot from CD drive (you might have to press F12, then 'c').
4) Unmount iBoot, mount Snow Leopard ISO.
5) Press F5, then Enter. It will launch the SL installer.
6) Open Disk Utility. Partition your disk - GUID, Mac OS Journaled. Close Disk Utility. Select the new drive partition you made, and let the install continue.
7) After installation, mount iBoot.iso again and this time choose your new SL installation which will boot.
8) Run the 10.6.6 combo updater, do not allow it to reboot.
9) Run Multibeast, select EasyBeast and the System Utilities. Install it.
10) Unmount the iBoot iso in Virtualbox and reboot into Snow Leopard. iBoot is now no longer required.

Optional Virtualbox settings:
1) Raise the Video memory to 128MB and enable 3D acceleration.
2) Raise the main RAM to 2GB or more if you can spare it.
3) Install the Virtualbox Extension Pack to enable USB device support.

Known issues:
1) "About This Mac" will crash the Finder. System Profiler works properly when invoked directly.
2) Shut down/restart etc. will always kernel panic.
3) There is no choice of resolutions in the Display settings. Use the Virtualbox command line to do e.g. VBoxManage setextradata “OSX” “CustomVideoMode1″ “1600×960×32”
4) Shared Virtualbox folders can't be used due to there being no Virtualbox Guest Additions for Mac (yet?)
5) Sometimes fails to boot and sits on the Apple splash screen spinner forever. Just reset it.
6) Spotlight sometimes hangs, and sometimes has to do a full reindex for no apparent reason.


version 2
1) Virtualbox 4 with the Oracle VM VirtualBox Extension Pack installed.
2) Snow Leopard retail DVD or ISO.

1) Make a new OSX Server image in Virtualbox, call it "OSX", use all the defaults except make a bigger disk than 20GB - 40GB is a better number.
2) Go into the settings.
3) If you have enough RAM, change the RAM to 2048MB, but no more.
4) Change the Video RAM to 64MB, and enable 3D Acceleration.
5) Make sure that the Audio is set to Intel HDA, and make sure that the DVD is ahead of the Hard Disk in the boot device order.
6) In the Storage tab, either mount the Snow Leopard ISO, or direct it to your physical DVD drive with the Snow Leopard disk in it.
7) Quit the Virtualbox manager.
8) Open a command prompt and 'cd' to your Virtualbox install directory (Probably "c:/Program Files/Oracle/Virtualbox".
9) (The following step might not be necessary, or actually do anything. Unconfirmed)... If you are on a 64 bit host type: VboxManage modifyvm "OSX" --firmware efi64
10) Type: VBoxManage setextradata "OSX" VBoxInternal2/EfiGopMode 4
Alternatively use 0, 1, 2 or 3 to set the video resolution according to:
0 - 640x480
1 - 800x600
2 - 1024x768
3 - 1280x1024
4 - 1440x900
11) In a text editor, edit the OSX.vbox file found in ~USERNAME/VirtualBox VMs/OSX/
12) Find the line that says ExtraDataItem name="VBoxInternal2/EfiGopMode" value="4"/
13) Below this line, paste the following (exactly, all on one line, inside angled quotes as with the other entries*)
ExtraDataItem name="VBoxInternal2/SmcDeviceKey" value="ourhardworkbythesewordsguardedpleasedontsteal(c)AppleComputerInc"/
14) Save the file and close your text editor.
15) Double click on the OSX.vbox file to launch the virtual machine.
16) After a little while, the Snow Leopard installer will start.
17) Open Disk Utility. Partition your disk - GUID, Mac OS Journaled. Close Disk Utility. Select the new drive partition you made, and let the install continue.
18) Optionally customize your install to remove language support, X11 support, printer drivers etc.
19) At the end of installation, it may crash when trying to reboot. In any case, unmount the DVD or ISO before either rebooting or resetting the Virtual machine.
20) Snow Leopard will boot from hard disk, go through the initial setup steps such as choosing timezone.
21) Run Software Update and bring everything up to date.
22) Take a backup of the OSX.vbox file in case Virtualbox manager later makes a change to it that causes your installation not to boot (e.g. removing the SmcDeviceKey line).

After installation (optional, maybe risky):
1) If CPU usage is always 100%, delete /System/Library/Extensions/AppleIntelCPUPowerManagement.kext and run 'sudo kextcache -system-caches' and reboot.
2) Edit the OSX.vbox file and raise the VRAM to 128MB.
3) If you deleted the kext above, you can add an extra CPU in Virtualbox manager.
4) EpiGopMode 5 is 1920x1200 if you have a big enough monitor.
5) Enable 64 bit Kernel by editing /Library/Preferences/SystemConfiguration/
Kernel Flags

Kernel Flags

Known issues:
1) Bootup is a verbose textual process rather than the Apple logo and spinner. Seems to be due to '-v' being hardcoded as a boot option in the emulated NVRAM.
2) Shared Virtualbox folders can't be used due to there being no Virtualbox Guest Additions for Mac (yet?)

* Blogspot won't let me enter things that look like raw HTML/XML.