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• Revisiting the Belco Alpha-400

  26 août 2010, par Multimedia Mike — General

  Relieved of the primary FATE maintenance duties, I decided to dust off my MIPS-based Belco Alpha-400 and try to get it doing FATE cycles. And just as I was about to get FATE running, I saw that Mans already got his MIPS-based Popcorn Hour device to run FATE. But here are my notes anyway.

  
  
  

  Getting A Prompt
  For my own benefit, I made a PDF to remind me precisely how to get a root prompt on the Alpha-400. The ‘jailbreak’ expression seems a little juvenile to me, but it seems to be in vogue right now.

  alpha-400-jailbreak.pdf

  Toolchain
  When I last tinkered with the Alpha-400, I was trying to build a toolchain that could build binaries to run on the unit’s MIPS chip, to no avail. Sometime last year, MichaelK put together x86_32-hosted toolchains that are able to build mipsel 32-bit binaries for Linux 2.4 and 2.6. The Alpha-400 uses a 2.4 kernel and the corresponding toolchain works famously for building current FFmpeg (--disable-devices is necessary for building).

  FATE Samples
  Next problem : Making the FATE suite available to the Alpha-400. I copied all of the FATE suite samples onto a VFAT-formatted SD card. The filename case is not preserved for all files which confounds me since it is preserved in other cases. I tried formatting the card for ext3 but the Alpha-400 would not mount it, even though /proc/filesystems lists ext3 (supporting an older version of ext3 ?).

  Alternative : Copy all of the FATE samples to the device’s rootfs. Space will be a little tight, though. Then again, there is over 600 MB of space free ; I misread earlier and thought there were only 300 MB free.

  Remote Execution
  To perform FATE cycles on a remote device, it helps to be able to SSH into that remote device. I don’t even want to know how complicated it would be to build OpenSSH for the device. However, the last time I brought up this topic, I learned about a lighter weight SSH replacement called Dropbear. It turns out that Dropbear runs great on this MIPS computer.

  Running FATE Remotely
  I thought all the pieces would be in place to run FATE at this point. However, there is one more issue : Running FATE on a remote system requires that the host and the target are sharing a filesystem somehow. My personal favorite remote filesystem method is sshfs which is supposed to work wherever there is an SSH server. That’s not entirely true, though– sshfs also requires sftp-server to be installed on the server side, a program that Dropbear does not currently provide.

  I’m not even going to think about getting Samba or NFS server software installed on the Alpha-400. According to the unit’s /proc/filesystems file, nfs is a supported filesystem. I hate setting up NFS but may see if I can get that working anyway.

  Residual Weirdness
  The unit comes with the venerable Busybox program (BusyBox v1.4.1 (2007-06-01 20:37:18 CST) multi-call binary) for most of its standard command line utilities. I noticed a quirk where BusyBox’s md5sum gives weird hex characters. This might be a known/fixed issue.

  Another item is that the Alpha-400′s /dev/null file only has rwxr-xr-x per default. This caused trouble when I first tried to scp using Dropbear using a newly-created, unprivileged user.

• Optical Drive Value Proposition

  28 août 2010, par Multimedia Mike — General

  I have the absolute worst luck in the optical drive department. Ever since I started building my own computers in 1995 — close to the beginning of the CD-ROM epoch — I have burned through a staggering number of optical drives. Seriously, especially in the time period between about 1995-1998, I was going through a new drive every 4-6 months or so. This was also during that CD-ROM speed race where the the drive packages kept advertising loftier ‘X’ speed ratings. I didn’t play a lot of CD-ROM games during that timeframe, though I did listen to quite a few audio CDs through the computer.

  
  
  

  I use “optical drive” as a general term to describe CD-ROM drives, CD-R/RW drives, DVD-ROM drives, DVD-R/RW drives, and drives capable of doing any combination of reading and writing CDs and DVDs. In my observation, optical media seems to be falling out of favor somewhat, giving way to online digital distribution for things like games and software, as well as flash drives and external hard drives vs. recordable or rewritable media for backup and sneakernet duty. Somewhere along the line, I started to buy computers that didn’t even have optical drives. That’s why I have purchased at least 2 external USB drives (seen in the picture above). I don’t have much confidence that either works correctly. My main desktop until recently, a Mac Mini, has an internal optical drive that grew flaky and unreliable a few months after the unit was purchased.

  I just have really rotten luck with optical drives. The most reliable drive in my house is the one on the headless machine that, until recently, was the main workhorse on the FATE farm. The eject switch didn’t work correctly so I have to log in remotely, 'sudo eject', walk to the other room, pop in the disc, walk back to the other room, and work with the disc.

  Maybe optical media is on its way out, but I still have many hundreds of CD-ROMs. Perhaps I should move forward on this brainstorm to archive all of my optical discs on hard drives (and then think of some data mining experiments, just for the academic appeal), before it’s too late ; optical discs don’t last forever.

  So if I needed a good optical drive, what should I consider ? I’ve always been the type to go cheap, I admit. Many of my optical drives were on the lower end of the cost spectrum, which might have played some role in their rapid replacement. However, I’m not sold on the idea that I’m getting quality just because I’m paying a higher price. That LG unit at the top of the pile up there was relatively pricey and still didn’t fare well in the long (or even medium) term.

  Come to think of it, I used to have a ridiculous stockpile of castoff (but somehow still functional) optical drives. So many, in fact, that in 2004 I had a full size PC tower that I filled with 4 working drives, just because I could. Okay, I admit that there was a period where I had some reliable drives.

  That might be an idea, actually– throw together such a computer for heavy duty archival purposes. I visited Weird Stuff Warehouse today (needed some PC100 RAM for an old machine and they came through) and I think I could put together such a box rather cheaply.

  It’s a dirty job, but… well, you know the rest.

• Failed to build gem native extension while installing rmovie gem

  12 janvier 2013, par Dmitry

  I am trying to install rmovie gem on Ubuntu Desktop 12.04 LTS. ffmpeg is installed but I'm getting this error :

  $ gem install rmovie
  
  Building native extensions.  This could take a while...
  
  ERROR:  Error installing rmovie:
  
      ERROR: Failed to build gem native extension.
  
  
  
          /home/ror_dev/.rvm/rubies/ruby-1.9.3-p362/bin/ruby extconf.rb
  
  gcc -c -fpic -g  qp_movie.c -o qp_movie.o
  
  In file included from qp_movie.c:4:0:
  
  qp_util.h:4:28: fatal error: ffmpeg/avcodec.h: No such file or directory
  
  compilation terminated.
  
  make: *** [qp_movie.o] Error 1
  
  checking for avcodec_init() in -lavcodec... yes
  
  checking for av_register_all() in -lavformat... yes
  
  checking for quadrupel_init() in -lquadrupel... no
  
  *** extconf.rb failed ***
  
  Could not create Makefile due to some reason, probably lack of
  
  necessary libraries and/or headers.  Check the mkmf.log file for more
  
  details.  You may need configuration options.
  
  
  
  Provided configuration options:
  
      --with-opt-dir
  
      --with-opt-include
  
      --without-opt-include=${opt-dir}/include
  
      --with-opt-lib
  
      --without-opt-lib=${opt-dir}/lib
  
      --with-make-prog
  
      --without-make-prog
  
      --srcdir=.
  
      --curdir
  
      --ruby=/home/ror_dev/.rvm/rubies/ruby-1.9.3-p362/bin/ruby
  
      --with-ffmpeg-dir
  
      --without-ffmpeg-dir
  
      --with-ffmpeg-include
  
      --without-ffmpeg-include=${ffmpeg-dir}/include
  
      --with-ffmpeg-lib
  
      --without-ffmpeg-lib=${ffmpeg-dir}/lib
  
      --with-quadrupel-dir
  
      --without-quadrupel-dir
  
      --with-quadrupel-include
  
      --without-quadrupel-include=${quadrupel-dir}/include
  
      --with-quadrupel-lib
  
      --without-quadrupel-lib=${quadrupel-dir}/lib
  
      --with-avcodeclib
  
      --without-avcodeclib
  
      --with-avformatlib
  
      --without-avformatlib
  
      --with-quadrupellib
  
      --without-quadrupellib
  
   extconf failed: need quadrupel library

  First attempt was to relocate avcodec to where installer is searching for it. No success. Next - correcting paths in quadrupel files to point it to where avcodec is located. No success.

  What is this quadrupel thing and how to force it to work ?

  Or maybe there is some replacement for rmovie ?