Sugus » experiments

Video speed controls on youtube’s HTML5 player

Pedro Assuncao — Thu, 18 Feb 2010 14:12:44 +0000

I don’t know if you noticed, but youtube introduced speed controls to their HTML5 video player. I have no idea if it was there from the beginning, actually, but it’s a really cool feature indeed

Bomb This Country

Pedro Assuncao — Tue, 16 Feb 2010 08:08:15 +0000

After an awesome Japanese dinner with my good friend Luizzz, we came to the conclusion that the website that was missing was one where you could bomb any country in the world. The motivation for this was part statistical curiosity and part plain bastardness (did i just make up another word?).

So over the course of about 8 hours – the next day – we came up with bombthiscountry.com, a meaningless website where you can bomb any country in the world (yes, China, Tibet is a country). If you follow it on twitter you get daily statistics on the most bombed countries in the world.

Websockets tutorial/example with pywebsocket

Pedro Assuncao — Fri, 18 Dec 2009 12:37:24 +0000

As everyone already knows, Google Chrome now supports websockets. In essence, this allows you to keep a connection open with a webserver indefinitely (analogous to typical sockets) and send data bi-directionally. Unfortunately Chrome is the only browser currently supporting this, but I’m pretty sure this will change.

So I decided to give this a try and experiment a bit with it. This is my step by step process on getting a web page opening a websocket to a server and receiving the server’s date and time every second. It is based on an article by Joe Armstrong, though he uses Erlang for the server, while I decided to follow the easy road and use Google’s pywebsocket – an apache module (uses mod_python) that allows you to create handlers for websocket connections in a easy-to-use fashion. The code also contains a way to start a standalone server (i.e. not requiring apache) for testing purposes.

So here are the steps I took to get this working:

1. Create a web page

This is the code I borrowed from Joe, though slightly modified to fit my purposes (it requires jquery, by the way):












Interaction experiment

Debug



Clock
I am a clock

2. Download and install pywebsocket

Checkout the code with

svn checkout http://pywebsocket.googlecode.com/svn/trunk/ pywebsocket-read-only

Then do python setup.py build and sudo python setup.py install inside the src folder. This will install it into your python environment.

3. Being lazy, means we will change an example handler

The way pywebsocket works is delegating the connections to something they call handlers. In the pywebsocket-read-only/src/example folder you will find a file named echo_wsh.py. They have this convention where handlers are named _wsh.py. This means that when you later call (from your web page) the url http://localhost:9998/echo the server will delegate the processing of that connection to that file.

I modified that file to something like this:

# Copyright 2009, Google Inc.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
#     * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
#     * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

from mod_pywebsocket import msgutil
from datetime import datetime
import time

_GOODBYE_MESSAGE = 'Goodbye'

def web_socket_do_extra_handshake(request):
 print 'Connected.'
 pass  # Always accept.

def web_socket_transfer_data(request):
 while True:
 time.sleep(1)
 date = datetime.now()
 #try:
 #    line = msgutil.receive_message(request)
 #except Exception, e:
 #    print 'Foi com os porcos'
 #    raise e
 #print 'Got something: %s' % line
 #msgutil.send_message(request, line)
 msgutil.send_message(request, 'clock!%s' % date)
 #if line == _GOODBYE_MESSAGE:
 #    return

So basically whenever a new connection is made to this entry point, a call to web_socket_do_extra_handshake is made. After that, web_socket_transfer_data is called and it’s your responsibility to create the loop that receives messages and handles the flow (as you can see in the commented lines). I don’t care about that right now, since I only want to push the date and time to the client every second.

3. Start the standalone server

Go to the pywebsocket-read-only/src/mod_pywebsocket folder and run the following command:

sudo python standalone.py -p 9998 -w ../example/

This will start the server in port 9998 and use the handlers directory specified by the -w option. That is where our echo_wsh.py lives.

4. Test it

So now open your browser (remember, only chrome supports websockets currently) and open the html file your created in the beginning. Voilá, server’s date and time every second in the clock div.

World’s deadliest ping pong cannon

Pedro Assuncao — Wed, 11 Nov 2009 17:00:10 +0000

I want one of these. I wonder who comes up with these things. Maybe the same guy that thought it was a good idea to shoot a satellite against the moon.

Dutch break world domino record

Asimo robot’s adaptative learning

Pedro Assuncao — Mon, 09 Nov 2009 10:27:38 +0000

Watch this video. Show some impressive developments on the artificial intelligence of the robot Asimo: Identifying objects, using features to extrapolate to other unknown ones.

The robot war is near

Dig a hole through Earth

Pedro Assuncao — Fri, 06 Nov 2009 23:01:07 +0000

Turns out that a hole made in my home country, Portugal, would end up in New Zealand:

Check the source website here, and figure out where your country leads to on the other side of the world

Shopping cart stunt failed

Pedro Assuncao — Fri, 06 Nov 2009 17:00:58 +0000

Every daring endeavor is prone to small hiccups along the way

Shopping bicycle. I want one.

“Early riser” experiment conclusions

Pedro Assuncao — Thu, 08 Oct 2009 11:56:35 +0000

In case you didn’t read my entry on becoming an “early riser” (i.e. someone that gets up every day at the same (early) hour), I started a 30 day experiment to see what would happen to me both physically and mentally if I did. These are the conclusions.

Let me start by giving some background: I’ve always been one of those people that said they require – at least – 9 hours of sleep every night. The reason for this, for me, was that I always felt sleepy during my work days, so another purpose of the experiment was to try to refute this myth of mine.

During the 30 days there was only one when I broke the “always get up at the same time without hitting the snooze button” rule. And it was a Saturday, so don’t hold it against me . Just kidding. The reason why I did it was to demonstrate to myself how hard it is to give up on the infamous snooze button in the morning. I know it happens to everyone: “just 5 more minutes”. And then you just do the same 5 minutes later. Let me tell you: It’s bad!!! It’s evil!!! It will help crush your motivation for pretty much everything else.

But I digress, let’s go back. During the experiment the minimum amount of hours I slept in any given night was 5. It did, however, happen in one of the first nights so I will ignore it and assume the next value as the minimum: 6 hours and 30 minutes. The longest I slept was 9.30 (also in the first days, probably to recover from the previous 5). My average sleep time, all nights considered, was 7:35.

Minimum	Maximum	Average
6:30	9:30	7:35

There are a couple of interesting small conclusions that I can take from a look at the complete sleep data:

As you move along in the experiment, you body starts to regulate itself: Since you basically control your waking up time, your body will start asking to sleep when it’s actually really tired. This makes, in my opinion, a better way of regulating your sleep pattern (1). As a side effect, it seems that you will indeed start to get low sleeping time deviations. I.e., there are no “freak” sleep occurrences, like sleeping 20 hours, or 2 hours (2);
My actual sleep needs are actually less than what I had expected. And physically I don’t feel any more tired than before. If anything, I feel more awake and energized.

Data apart, I am sure that you will:

Feel more energized every morning after waking up instantly;
Usually wake up 1-2 minutes before the alarm clock triggers;
Experience a greater motivation, especially to work on personal stuff (pet projects, for instance);
Have a lot more time on your hands. Your weekends will feel like an entire week, with everything you can accomplish instead of being asleep for 4 more hours like I used to;

I also read in the post that motivated this that, generally, your mind would slowly start to give you a broader picture on your problems, instead of focusing so much on the details. I cannot say I have experienced this shift, but I do agree that a little more motivation goes a long way to make you think harder about the problems and their solutions, and that might have been what Steve referred to when he wrote that.

I hope you found the article interesting and I would definitely like to hear about your experiences on the subject

Peace.

NOTES:

(1) If you think about it the other way around you can understand it better. Imagine that you always go to bed at the same time. The problem with this is that you usually have a schedule of some sort to keep. Which forces you do one of two things: Either you don’t sleep enough or you go to bed when you still are not sleepy enough (and basically stay in bed wasting time). This approach makes it much harder for your body to regulate the sleep pattern. On the other hand, if you always wake up at the same time, you will never have problems with being on time for your appointments and you still make sure that you sleep enough (and only the required amount) because your body will be the one to tell you when it needs to sleep.

(2) Provided, of course, you don’t stay up getting hammered with friends at the local bar. But fear not, your body will ask to recover the next night, by making you sleep a lot earlier. The main thing to keep in mind is that you should never break the getting up rule.

Trying to become an early riser

Pedro Assuncao — Tue, 08 Sep 2009 09:34:02 +0000

After reading a post by Steve Pavlina I thought if I could become a natural early riser, i.e, someone that gets up really early in the morning and has no problem with that. I felt curious when I read that, after turning into an early riser, he became more productive and felt more refreshed throughout the day.

Being someone who always thought that I *really* need 9 hours of sleep everyday (no matter the time I get up or go to sleep), I just had to try for myself.

I must say that I’m usually not into that whole “personal development” thing that Steve Pavlina advertises and sells, but I decided to give his advice a try. In essence:

Get up every day at the same time (I chose 7am), no matter the time you go to bed;
Go to bed only when you are really sleepy. Like when you can’t read one page of a book without dozing off.

I’m currently in day 4 of the experiment and the first 2 days were – for obvious reasons – a bit chaotic. Although I was really productive, it felt like I didn’t sleep enough. Did I mention these 2 days were Saturday and Sunday?

Let me know if you tried something like this and what were your results.