Category: Linux
Flickr Downloadr that really works
Not my work. Get it here.
It does exactly what it says on the tin. This is letting me close a years-old open loop I had, which is that Flickr had a lot of my photos, but sucked so bad that I didn’t want to reward them with money in order to get my photos back.
As soon as the download is done, that Flickr account is toast.
Un-Ubuntuing Ubuntu, Again
Ubuntu makes no secret of the fact that they will choose something that looks good but doesn’t work over something that works. That’s pretty much the entire point of this blog post. Because xscreensaver uses an older X widget kit than light-locker, and so looks “antiquated”, they switched to light-locker for 14.04. Light-locker doesn’t atually work well, and causes many, many, many laptops to not return from suspend mode without a hard reset.
If you’d rather use software that works, you have to change some settings and remove a bunch of stuff. I removed light-locker, light-locker-settings, and gnome-screensaver. I also installed xscreensaver.
In order to lock on lid close, I started xfce4-settings-editor, selected xfce4-power-manager, and set/checked both lock-screen-suspend-hibernate and logind-handle-lid-swtich.
I currently get two login prompts when I unsuspend, one from xscreensaver and one from something else. I suspect the second one is logind, so I can get rid of the xscreensaver one by making xscreensaver not do screen locking.
Well THAT'S messy
for file in ../connections_2014-10-7-1*; do conn="-c ../connections_"`echo $file | cut -d "_" -f 2`; types="-t ../neuron_types_"`echo $file | cut -d "_" -f 2`; locs="-l ../locations_"`echo $file | cut -d "_" -f 2`; ./pickle_to_json.py $conn $types $locs; done
For all the connection files that were generated today, create three variables called “conn”, “types”, and “locs” that have a command line switch path in them generated from a fixed prefix and a cut from the connection file name. Then invoke the script “pickle_to_json.py” with those variables as arguments.
Effectively, the connection, neuron type, and location files are all related by their date, so this makes a single JSON file out of the multiple files. I just didn’t want to run pickle_to_json.py a bunch of times by hand, as that seemed error-prone.
I waste time to not waste time
I’m using a web server on my local machine plus an edited /etc/hosts file to serve up a page that reminds me to get back to work when I should be getting back to work, rather than, say, reading facebook. Yes, I can get around this by clearing my hosts file, but that makes it work to get to the blocked sites, and if I’m going to be doing work, it’s not time-wasting is it?
The hosts file looks like this:
ams@robot-lab7:~/weblock$ cat /etc/hosts
127.0.0.1 localhost.localdomain localhost
#I elided a couple of lines here
127.0.0.1 www.facebook.com facebook.com
127.0.0.1 www.dresdencodak.com dresdencodak.com
127.0.0.1 www.xkcd.com xkcd.com
127.0.0.1 www.boingboing.net boingboing.net
127.0.0.1 ab3nd.livejournal.com livejournal.com
127.0.0.1 www.questionablecontent.net questionablecontent.net
127.0.0.1 www.hackday.com hackaday.com
# The following lines are desirable for IPv6 capable hosts
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
That takes care of redirecting a lot of pages to localhost, rather than their real IP addresses. On my computer, I have a little web server, which is launched with the command
sudo webfsd -p 80 -f index.htm -u ams -r /home/ams/weblock/
Webfs, and it’s daemon part webfsd, is a static-file-only http server. In this invocation, it runs as my user after binding to port 80 as root, and serves the file index.htm out of the directory /home/ams/weblock. That file is a very simple HTML file:
<div style=”display: table; height: 100%; width: 100%; background: #fff; _position: relative; overflow: hidden;”>
<div style=”_position: absolute; _top: 50%; display: table-cell; vertical-align: middle; text-align: center;”>
<h1>What should you be doing?</h1>
</div>
</div>
It just shows the text “What should you be doing?” in the middle of the page. This is also interesting because it shows how to center HTML content in the middle of the page, at least for small content. I’m not sure how well this works with larger or more complex content.
Un-ubuntuing Ubuntu…
..post one of several million, no doubt. Ubuntu is pretty good, but persists in making what I’d regard as irritating desktop usability blunders. One of them is the use of “overlay scrollbars” which are scrollbars that are mostly hidden until you mouse over them. I found this annoying, but whatever, I can deal. It even more or less works, most of the time.
However, it breaks Inkscape. Inkscape’s color picker is a long strip of color patches, which you can click to select stroke and fill colors for drawings. The color picker has a scrollbar. If overlay scrollbars are on, then the entire area of the color picker ends up being the mouse-over area for the overlay scrollbar, so you can’t pick colors.
The fix is to issue the command “gsettings set com.canonical.desktop.interface scrollbar-mode normal” from the command line.
Useful mencoder invocation
mencoder -nosound mf://*.jpg -mf w=1280:h=800:type=jpg:fps=30 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=2400:mbd=2:keyint=132:v4mv:vqmin=3:lumi_mask=0.07:dark_mask=0.2:mpeg_quant:scplx_mask=0.1:tcplx_mask=0.1:naq -o output_filename.avi
Turns all the JPEG files in the directory you are currently in into a nice quality MPEG-4/AVI file. The width and height in the options after -mf should be changed to match the images. This command line also works for PNG files if you replace both instances of “jpg” with “png”.
Command Line Audio Editing With Sox
For my ritual spoken word software piece, I recruited a bunch of my friends to say the text of the ritual. Each “stanza” of the ritual has a call and a response, so I broke each recording up into individual clips for each call and response. That gave me about 28 files per person, and over 100 clips total.
The different participants all recorded on different hardware, and at different volume levels. I also wasn’t super-precise about trimming the clips, so each file had silence at the beginning.
This left me with two problems: some participants were much softer than others, and some of the clips lagged each other, which made for bad chorus effects.
To trim the clips, I used sox, a Linux tool for manipulating sounds, with the command:
for file in *.wav; do sox $file $file.wav silence 1 0.1 2%
This results in a file named foo.wav.wav for each foo.wav file in the directory, so I cleaned up with:
rename -f “s/.wav././g” *
Note that this scribbles over the originals, so keep backups. I’m glad I did, because 2% turned out to be a little aggressive, and trimmed off the beginning of clips starting with an “ma-” sound, such as “make us a…”. This is likely because the sound faded in slowly, and so got counted as part of the noise rather than the beginning of a sound.
There is useful documentation for the sox silence filter here.
Turning the volume up on the files was done with:
for file in *.wav; do sox $file $file.wav gain -l 8; done
and another pass of rename, as above. Adjust the “8” up or down to suit your needs. Positive numbers make it louder, negative make it quieter.
If you want to preview a sox effect, just replace “sox” in the command with “play”, and leave off the output file. For example,
play myfile.wav gain -l 8
will play myfile.wav with increased gain, but won’t change the file.
We Make Ritual Noise
For a festival that I attend, I’m writing a soundscape in boodler to provide the vocal component for a ritual. Here, I’m going to annotate what I need to do to run Boodler on my laptop, which I’ll have at the festival.
The main thing is that Boodler seems to default to OSS, and I use PulseAudio, so to invoke the ritual, you need to run:
boodler -o pulse –external disturbingrelics com.gizmosmith.disturbingrelics/Example
The -o option tells it to use PulseAudio, –external makes it load from a directory instead of a .boop package for testing purposes, and the rest is the agent to run.
To organize all the sound clips I’m using, I have a boodler package for each person’s reading of the ritual script. The script is in a call and response format, with 14 calls and responses, so each package has 28 audio clips, one each for the call and response. I named all the clips “call_N_…” and “response_N_…” (for N in 1..14) so that the program can figure out the call/response pairs by name.
Each package starts out as a directory with the 28 files and a metadata file in them. For the directory “sage”, I create the package with:
boodle-mgr –import create sage
and then install it with:
boodle-mgr install ./com.gizmosmith.sage.1.0.boop
Converting .MPG to .AVI with Linux programs
I am trying to convert .mpg files from a sony camera into other, smaller versions for distribution. The files are in the mpeg2video codec, with a resolution of 720×480 at 29.97 fps. Normally, I’d use ffmpeg for this, but apparently “This program is only provided for compatibility and will be removed in a future release. Please use avconv instead.” Thanks Ubuntu, I’m sure that won’t screw up a few thousand people’s video conversion scripts.
Anyway, let’s see what man avconv has to say. I want no sound, and I want to start 55 seconds into the film, to cut off most of a boring first minute. Seeking into the video is -ss 00:00:55. The option -an drops the audio. So, avconv -i blue_ball.mpg -an -ss 00:00:55 blue_ball.avi should do it. And, in fact, it does.
Cross-system chat log sync
I created a directory called “pidgin_logs” in my Dropbox folder, backed up my logs, removed the old log directory, and then created a link from where the log directory should have been to the Dropbox directory. Pidgin still starts up fine, and after I do this on all of my systems, they will all log chats to my Dropbox account.
I’m not sure I’m comfortable with the level of trust that this places in Dropbox, but it will be very convenient.
The commands to do it are:
cd ~/Dropbox/ mkdir pidgin_logs cd ~/.purple/ mv logs logs_backup mkdir logs ln -sfn ~/Dropbox/pidgin_logs ~/.purple/logs mv logs_backup/aim logs/ mv logs_backup/jabber logs/
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