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  • Stef 11:36 am on 11 June, 2013 Permalink | Reply
    Tags: activity board, ,   

    OpenStack Activity Board in the news 

    I think this is the first time a reporter quotes data from OpenStack Activity Board. It makes me proud that Sean Michale Kerner aka @TechJournalist noticed how open the data is.

    Drilling down into the data that OpenStack (true to its nature) keeps very open – in the last month alone there were 313 unique authors and 2,512 code commits.

    Can’t wait to take the project to its next phase.

    via OpenStack Open Source Cloud Crosses 1000 Author Threshold

     
  • Stef 11:52 am on 7 June, 2013 Permalink | Reply
    Tags: , , , ,   

    How to survive to high traffic mailing lists 

    From the Metrics Grimoire mailing list, I have found out about this masterpiece by Joey Hess: how to subscribe to mailing lists with a combined total posts of 2000 or more per day, and live. I enjoyed reading it although now I’m getting the depressing thoughts of bad email clients :(

     
  • Stef 4:26 pm on 5 May, 2013 Permalink | Reply
    Tags: , , , , , workspace   

    Ubuntu is getting closer to Windows and Mac (in a dumb way) 

    I’ve always thought that the Ubuntu team “got it right”: I found Unity beautiful, the whole integration of different pieces among different projects, the simplifications and removal of unnecessary options was good. Then I started noticing the over-removal of things. First went CTRL-Alt-Backspace, the very useful combo that kills the windows server. I almost never need it but when I needed I realized it was disabled by default some time ago. I didn’t complain too much as the feature is pretty advanced and I have found myself killing the session unintentionally hitting the combo with fat-fingers a couple of times. So I thought the choice made sense. But today the line between simplification and dumbification  has been crossed: Ubuntu Raring Ringtail 13.04 has disabled the virtual workspaces by default.

    Today I upgraded to Ubuntu 13.04. At reboot I wanted to start my apps in the usual workspaces : 1 for the browser and mail, 3 for xchat… but OMG! CTRL-Alt-DOWN doesn’t work… Quick search first to learn what the heck those things are called then the sad truth: workspaces are disabled! What a moronic choice to disable them by default. Guys, come on! I understand making things simple, but dumbing down on Mac and Windows on their limitations is a stupid choice.

    To enable them again there is a settings in the panel as described on Ask Ubuntu. I feel like my respect for Ubuntu’s team is at its lowest point ever and this makes me unhappy.

    I think removing the workspaces is the dumbest idea ever, on par with grouping windows from the same app in the Alt-Tab cycle. Please somebody explains why. Is this because Microsoft doesn’t have workspaces, so we should copy them, right? Wrong! What’s next? Disable paste with middle-click? I might as well go buy a Mac then or learn how to live with Windows if I have to learn and live with moronic systems.

     
    • Pranav Salunke 8:14 pm on 5 May, 2013 Permalink | Reply

      Well, just imagine non-geeky non-techy guys switching to Ubuntu it is very confusing at start. May be it is because of that they disable work-spaces by default. I just hope that they don’t do more changes like this. Although agree with you on how dumb this release can get.

      • Stef 8:30 am on 6 May, 2013 Permalink | Reply

        Even if disabling workspaces is for new Ubuntu users, why on earth does the installer disables them for *old* users like me during the *upgrade* (not a fresh install)? I found this bug https://bugs.launchpad.net/ayatana-design/+bug/868423 where the rationale for this move is explained… The answer is not convincing and there is no evidence to support the decision. If this was my product I would have preferred to keep the option and worked on teaching new users how to make advantage of it: you gain users by showing the power of a tool, not by dumbing it down to the lowest common denominator.

    • AleLorenzi 11:48 pm on 5 May, 2013 Permalink | Reply

      I used unity once, it wasn’t my laptop and there was tons of notifications. That gets me crazy, notifications for emails (mostly spam), notifications for tweets (spam again), gTalk notifications, facebook notifications, facebook chat notifications.

      …and…

      tons of windows opened in a single workspace. ARGH! :x

  • Stef 9:46 am on 10 April, 2013 Permalink | Reply  

    Fun With OpenStack Visualizations 

    The visual representations of activity in source code repositories seem to be appreciated by many people. I started to play a bit with gource, a software version control visualization tool and update the videos made to represent the activity on OpenStack repositories.

    git log –pretty=format:user:%aN%n%ct –reverse –raw –encoding=UTF-8 –no-renames –no-merges |\
    gource \
    –title “OpenStack Block Storage – A Visual Development History”\
    -1280×720 \
    -f \
    –hide mouse,filenames \
    –logo /home/reed/Documents/lavoro/openstack/openstack-logo-small.png \
    –background-image /home/reed/Documents/lavoro/openstack/openstack-page-bkg.jpg \
    –font-colour 535353 \
    –highlight-users \
    –highlight-colour CF2F19 \
    –selection-colour 325C6B \
    –dir-colour 325C6B \
    –seconds-per-day .5 \
    -c 2 \
    –max-file-lag 0.1 \
    -o – | \
    ffmpeg -y -r 60 -f image2pipe -vcodec ppm -i – -vcodec libvpx -b 10000K cinder-2013-04.webm

    The challenge is to make the videos the same length or at least an acceptable ‘web’ length (closer to 3 minutes than 12 minutes). I played with the –seconds-per-day option and the -c of gource trying to find an acceptable speed.

    There is very good music on ccMixter, especially in the Music for Games and Videos section appropriate for this sort of projects and OpenShot helped made the titles and mixing the audio and video tracks. Results will appear soon on OpenStack Foundation’s YouTube channel.

     
  • Stef 4:16 pm on 23 March, 2013 Permalink | Reply
    Tags: , , , , ,   

    Streaming Audio from Raspberry Pi – part 2 

    Episode two of my experiment with the Raspberry Pi I have received at Pycon 2013. On the way back from Santa Clara I stopped by Fry’s and bought the only USB sound card they had in store, a weird looking Creative and a powered USB hub.  I ordered also a case from Adafruit industries (not convinced of the case though).

    Raspberry Pi and USB sound card
    The output of lsusb:

    Bus 001 Device 006: ID 147a:e03d Formosa Industrial Computing, Inc.

    Hooked them all together, installed avahi-daemon on the Pi so I can ssh into it easily from any lan (ssh raspberrypi.local, although I should change its name to something more unique). Tested arecord locally first. It took me a while to figure out how to use arecord, it’s old stuff that I’m not very used to. You need to specify the hardware device. If you get this sort of error:

    arecord: main:682: audio open error: No such file or directory

    probably you haven’t specified that you want to record from the card that actually has an input device

    pi@raspberrypi ~ $ arecord -l
    **** List of CAPTURE Hardware Devices ****
    card 1: Audio [2 Channel USB Audio], device 0: USB Audio [USB Audio]
    Subdevices: 1/1
    Subdevice #0: subdevice #0

    I hooked my phone’s audio player to the mic input of the USB card so that there would be constantly audio coming in the Pi, then started recording

    pi@raspberrypi ~ $ arecord -D hw:1,0 -f s16_le -c 2 > test.wav

    I have specified the hardware device I want to use, the format and the number of channels. Playing back that file worked.

    pi@raspberrypi ~ $ aplay -D hw:1,0 test.wav

    Next step was to capture live audio from the line input of the USB card, transcode that to OGG Vorbis and ship the bits to the remote Icecast server I setup last week. I quickly gave up on ezstream and started using ices2, the Icecast client: it seems easier to manage as it takes care of the encoding. This is the input module I used for the Pi:

    <input>
    <module>alsa</module>
    <param name=”rate”>16000</param>
    <param name=”channels”>2</param>
    <param name=”device”>hw:1,0</param>
    <!– Read metadata (from stdin by default, or –>
    <!– filename defined below (if the latter, only on SIGUSR1) –>
    <param name=”metadata”>1</param>
    <param name=”metadatafilename”>liveaudio</param>
    </input>

    The USB soundcard I’m using sends 16000hz samples. I chose not to resample that, only to downmix stereo to mono to save bandwidth.

    <–  stereo->mono downmixing, enabled by setting this to 1 –>
    <downmix>1</downmix>

    And all seems to work: the Pi sends a clear signal up to the streaming server and it’s been doing that for a while. Big success so far. Next step for me will be to write a script that grabs data from the OpenStack Summit schedule for one room and adds that information as metadata for the streaming: this way the listeners will have an idea of who is speaking or what the session is about.

    Update: the stream was having a wide latency, around 20 seconds so I decided to play a little bit with the sampling rates. The latency went down to around 1 second using  <param name=”rate”>48000</param> in the input module and  <samplerate>48000</samplerate> in the encode module, with no resampling. Unfortunately the USB card dies every now and then when not connected through a powered USB hub. Too bad, because the USB hub looks ugly.

     
    • Ole N 11:58 pm on 14 May, 2013 Permalink | Reply

      Could you please give som more information about that soundcard? Can’t find it at Creative.

    • stefano zorzanello 4:31 pm on 15 May, 2013 Permalink | Reply

      Hi Stef,
      thank you for your great report about Pi audio streaming…..
      I’m completely new to this great world
      I would like to know if you think the Raspberry Pi would be the right shield for my project.

      I am a musician and sound designer, using Max/Msp, particularly interested on soundscape projects and researches, and this project is for an interactive sound installation in a real environment, with the sound produced by cicadas. As I’d prefer not to abandon a computer in a field, I assumed to use a microcontroller for this purpose.

      So Raspberry Pi should be involved in steps 1-2-4-5 of the following:

      1) sampling the sound locally produced by cicadas males during summer: mono signal is fine.
      2) sending a stream of samples through the web in real time: Raspberry Pi should be connected to the web via 3G (no ethernet cable).
      3) another computer placed in a studio should get this stream, making the audio treatments, re-sending it trough the web (splitted possibly into four independent synchronized channels-signals)
      4) downloading the 4 processed streams;
      5) distributing the sounds on a local multi speaker system, 4 channels basically.

      If you think that all this is feasible through a Raspberry Pi plus a proper internet networking shield, I would buy it as soon as possible. Could you also tell me in case it would be possible with only 2 channels (stereo) playing?

      I thank you very much for your attention, I stay waiting form an answer from you.

      Best regards

      stefano zorzanello

      • Stef 4:40 pm on 15 May, 2013 Permalink | Reply

        Hi Stefano, your project sounds interesting. I think you can do step 2 with the Pi but you’ll need to find a USB GPRS modem that supports ARM Linux drivers. I have no idea about that though. Also, I found the soundcard I bought not to be very stable: at times the driver seems to crash and the streaming stops. Unfortunately I have very little time to debug this. I’m considering shopping for a board that has native audio input and similar cost.

    • stefano zorzanello 5:10 pm on 15 May, 2013 Permalink | Reply

      thank you for your interest!
      yes I’ve to look for this USB GPRS modem that supports ARM Linux drivers……. maybe this will be the rock to climb…. I’, pretty sure you will find a more stable sound card…
      I was wandering for arduino plus audio codec shields… but it seems that arduino has not enough resources to support both 3g shield and audio codec at the same time……
      any way I’ll keep on studying the feasibility…

      in the while thank you very much..

      ciao

      stefano (so I have to avoid to sign myself “Stef” as I usually do!!)

  • Stef 3:41 pm on 17 March, 2013 Permalink | Reply
    Tags: , , ,   

    Simple live audio streaming from OpenStack Summit using RaspberryPi 

    I have always wanted to have a simple way to stream audio from the OpenStack Design Summits, much like Ubuntu used to do for its Ubuntu Design Summit. Since every participant to Pycon 2013 was kindly given a Raspberry Pi and having a couple of hours to kill, I have started playing with a simple idea: configure a Raspberry Pi to capture audio and stream it to a public icecast server.

    First thing: spin up a virtual machine on a public cloud that will be serving as public icecast server. I have used my UniCloud account, created a small server, 512Mb ram, Ubuntu LTS 32bit. I updated the default security groups to allow traffic on port 22 (SSH) and 8000 (icecast), and I also needed to assign a public floating IP.  Once the machine is up, simple apt-get install icecast2 took care of starting the audio streaming server. That’s it, streaming server part is done.

    Back to the RasPi, in order to test the streaming server, I installed ezstream, copied the config files from /usr/share/doc/ezstream/examples. I copied ezstream_vorbis.xml to pi home dir:

    <ezstream>
    <url>http://INSTANCE_NAME:8000/armin</url&gt;
    <sourcepassword>TheSecret</sourcepassword>
    <format>VORBIS</format>
    <filename>playlist.m3u</filename>
    <!– looping the stream forever, for testing purposes –>
    <stream_once>0</stream_once>
    <svrinfoname>OpenStack Test Streaming Rradio</svrinfoname>
    <svrinfourl>http://radio.openstack.org</svrinfourl&gt;
    <svrinfogenre>OpenStack Test Streaming</svrinfogenre>
    <svrinfodescription></svrinfodescription>
    <svrinfobitrate>320</svrinfobitrate>
    <svrinfochannels>2</svrinfochannels>
    <svrinfosamplerate>44100</svrinfosamplerate>
    <!– advertising on public YP directory –>
    <svrinfopublic>1</svrinfopublic>
    </ezstream>

    The playlist.m3u is a simple text file with one .ogg file in there, enough to test it. Start the stream to be sent to the icecast server with

    ezstream -c ezstream_vorbis.

    And go play the audio in your favorite icecast player, the URL is something like http://YOUR_INSTANCE_NAME:8000/vorbis.ogg.m3u

    Simple, rudimentary but I like because it seems to be easy. The next step for me is to buy a USB microphone to stream live audio captured in a room. The optimal configuration though is to use this system to stream audio easily from the OpenStack Summit rooms. I need a way to connect the USB input to a regular audio mixer: any idea on how to do that?

     
  • Stef 11:05 am on 1 March, 2013 Permalink | Reply
    Tags: glass, ,   

    The Google Glass creepy feature 

    Interesting read The Google Glass feature no one is talking about.

    Just think: if a million Google Glasses go out into the world and start storing audio and video of the world around them, the scope of Google search suddenly gets much, much bigger, and that search index will include you.

    Google Glass is one step above and beyond personal espionage: your face captured and archived, your voice, including the things you say when nobody watches, stored forever without you knowing, matched with your full name, as you specified it in Google+ or on your Android phone… Definitely this is the conversation the tech community should have.

     
  • Stef 1:04 pm on 28 February, 2013 Permalink | Reply
    Tags: , ,   

    Being first to market may not be an advantage 

    A short video from MinuteMBA shows how Apple won being getting there second. It’s a good reminder that being first doesn’t mean always winning.

    3 Ways Apple Actually Innovates – OnlineMBA.com.

     
    • Ben Tremblay 3:55 pm on 11 April, 2013 Permalink | Reply

      What haunts me: to deploy my system in one form only to have the design re-factored and deployed elsewhere, scooping future growth.

      Gotta start up running full speed!

      –@bentrem | @ITGeek

  • Stef 4:05 am on 31 January, 2013 Permalink | Reply  

    Surface travels 

    20130131-130316.jpg

    As opposed to flying. The landscape is beautiful just the same, crossing the Apennines on a slow train between Foggia heading to Roma.

     
  • Stef 1:59 am on 15 January, 2013 Permalink | Reply
    Tags: , car, , laptop, weird, wheel   

    Car dashboards are ready for disruption 

    The Wheelmate Laptop Steering Wheel Desk on Amazon seems like a joke but I believe it highlights how bad the dashboards of current cars are. I drive rarely but when I do I realize that in normal cars there is no easy way to take a fast note on a laptop *while parked* after a meeting. There is a place to put your travel mug, all sort of electric outlets and adapters but no retractable desk, not even for the passenger/shotgun seat. I think dashboards are ready for disruption.

    PS comments and pictures on Amazon are hilarious

     

     
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