Peterbe.com

I have an application where I need to resize huge digital camera pictures down to 800x600 pixels. To do this I used ImageMagick's convert program which I feel gives much better quality than Python PIL. To reduce the file size I make sure I use the -strip option to convert but the really interesting question was what quality option should I use?

Goal: the image should be as small (in bytes) as possible without too reduced in picture quality.

To get the optimal picture quality of course the right option is -quality 100 and to get the smallest file size I should use -quality 10. To find out what quality setting to use I converted an original image with the following command 10 times:

convert vase.jpg -strip -quality <X> -resize 800x600 vase.quality-95.jpg

where <X> is the varying value between 10 to 100.

For the print.css stylesheet I wanted to hide away several of the "interactive" things such as some forms and stuff. This is the code I used:

img.camera,
img.edit,
table.expenses input, 
#shownfields, 
input[type="submit"],
.exportlinks 
{ display: none }

Works like a charm in Firefox but in IE (version 6 at least) none of them were applied. If I removed the input[type="submit"] selector the other ones worked. Is this a bug in Internet Explorer? Or have I declared it incorrectly. The W3C CSS validator sure doesn't hold me guilty. Here's what the code looks like now:

img.camera,
img.edit,
table.expenses input, 
#shownfields, 
.exportlinks 
{ display: none }
/* If you run Firefox or like you won't have to see 
   the submit buttons when you print this page. */
input[type="submit"] { display: none }

Don't do the silly misstake that I did today. I improved my code to better support unicode by replacing all plain strings with unicode strings. In there I had code that looked like this:

if type_ is 'textarea':
   do something

This was changed to:

if type_ is u'textarea':
   do something

And it no longer matched since type_ was a normal ascii string. The correct wat to do these things is like this:

if type_ == u'textarea':
    do something
elif type_ is None:
    do something else

Remember:

>>> "peter" is u"peter"
False
>>> "peter" == u"peter"
True
>>> None is None
True
>>> None == None
True

"Scientists say the global energy crisis can be solved by using the desert sun"

I've been wondering for a long time why the open deserts in north Africa isn't used for solar energy. There's 3 times as much sun there as there is in Europe. Unlike wind power plants in Europe, there's plenty of space for solar energy mirrors on the vast stretches of the north African desert.

This Guardian article is really interesting for me. Here are some interesting facts:

"[the two German scientists] calculate that covering just 0.5% of the world's hot deserts with a technology called concentrated solar power (CSP) would provide the world's entire electricity needs"

"Together the region could provide all its electricity needs by 2050 with barely any fossil fuels and no nuclear power. This would allow a 70% reduction in carbon dioxide emissions from electricity production over the period."

The article also sheds some light on the comparison of fusion reactors compared to solar power.

"The outlook is not promising. More than 30 countries last week agreed to spend £7bn on an experimental fusion reactor in France which critics say will not produce any electricity for 50 years, if at all."

I often use the Zope management interface but not to do much ZMI like stuff. Just simple things like creating new base objects, changing properties or testing a change to a template. For some reason I seem to lack the ability to spell the word manage_main. I can't remember how many times I've accidently typed manage-main , mange_main, manag_main, manage)_main etc.

There's got to be an end to that! Hence the MUnderscorePatch monkey patch. Now, all I have to do is to type in m_ at the end of the URL and it becomes the same as manage_main. Ie. I go to http://localhost:8080/ then I append m_ so that it becomes http://localhost:8080/m_ and it redirects automatically to http://localhost:8080/manage_main

Silly but actually quite useful for me. Want to download it too?

Zope is really great with it's publisher transform things that automatically cast HTTP GET or HTTP POST variables as proper python variables on the fly. I needed a form that asks for a Title and Description in multiple languages. The result I wanted passed into the saving method was variables like this:

>>> titles
{'en': u'London', 'sv': u'Stockholm'}
>>> descriptions
{'en': u'Capital', 'sv': u'Huvudstad'}

How did I write that form? Easy, here's the code:

<b>Title</b><br />
Svenska: <input name="title.sv:record" /><br />
English: <input name="title.en:record" /><br />
<b>Description</b>
Svenska: <input name="description.sv:record" /><br />
English: <input name="description.en:record" /><br />

As some of my friends on this website have might have noticed, I was threatened by Carphone Ware because of supposed defamatory comments made on this page

Here's an interesting article on BBC News about a case (in USA I should add) where a blogger could not be sued for the comments other people placed on her blog.

"Overturning a decision by the San Francisco appeal court, the court ruled that people claiming they were defamed online could now only seek damages from the original author of the comments - and not the website which re-posted it."

I need to think a bit more about it before I resurrect the currently removed comments from the page about Carphone Warehouse.

What a good little website this is! It's a database with nutritional information about different kinds of food, like bran flakes, meatballs or hot dogs

The search isn't great but it could just be because it's a limited database they have to work with. One immediate piece of feedback; it'd be great if when you do a search that it shows the search form again if you want to change your search term when you're confronted by the results. Look for example at this search result

Here are some amazing images of a less than safe road somewhere in China. I get an uncomfortable feeling in my stomage of just watching these but still deep inside I really want to go there and experience it myself. ...if my mom would let me, that is.

I know that they've got some similar roads in Spain but I can't remember where so I can't dig up any pictures.

My Firefox froze in one of the tabs when in another tab I had a long Fry-IT intranet blog half finished. To avoid having to rewrite the whole text again Jan showed me how to dump the RAM memory onto disk which I could then look through with standard tools. For this to work you have plenty of diskspace since the dump file is about 1Gb big:

$ sudo su -
# df -h
# cat /proc/kcore > /usr/kcore.dump
# strings /usr/kcore.dump > /usr/kcore.strings
# ls -lh | grep kcore
-rw-r--r--   1 root    root    1016M 2006-10-30 10:18 kcore.dump
-rw-r--r--   1 root    root      74M 2006-10-30 10:19 kcore.strings
# less kcore.strings | grep 'Bla bla bla'

Was this the most boring blog item I've written in a long time? Maybe, but it's good to have it noted the next time Firefox crashes.