GarciaPL Notes - Java and Others

Have you ever thought how receive the bitrate of your video/audio file using ffmpeg in command line ? Before I will show you a solution of this problem I would like to paste below some example output of video file which can be obtained using ffmpeg :

ffmpeg version git-2013-10-30-94a80e3 Copyright (c) 2000-2013 the FFmpeg developers
  built on Oct 30 2013 15:46:23 with gcc 4.8 (Ubuntu/Linaro 4.8.1-10ubuntu8)
  configuration: --prefix=/home/user/ffmpeg_build --extra-cflags=-I/home/user/ffmpeg_build/include --extra-ldflags=-L/home/luszcwoj/ffmpeg_build/lib --bindir=/home/luszcwoj/bin --extra-libs=-ldl --enable-gpl --enable-libass --enable-libfdk-aac --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-nonfree --enable-x11grab
  libavutil      52. 48.100 / 52. 48.100
  libavcodec     55. 39.100 / 55. 39.100
  libavformat    55. 19.104 / 55. 19.104
  libavdevice    55.  5.100 / 55.  5.100
  libavfilter     3. 90.100 /  3. 90.100
  libswscale      2.  5.101 /  2.  5.101
  libswresample   0. 17.104 /  0. 17.104
  libpostproc    52.  3.100 / 52.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'aquarium.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 0
    compatible_brands: isom3gp4
    creation_time   : 2013-09-08 23:38:41
  Duration: 00:00:03.44, start: 0.000000, bitrate: 3933 kb/s
    Stream #0:0(eng): Video: h264 (Baseline) (avc1 / 0x31637661), yuvj420p(pc), 640x480 [SAR 1:1 DAR 4:3], 2250 kb/s, 29.70 fps, 29.67 tbr, 90k tbn, 30 tbc (default)
    Metadata:
      creation_time   : 2013-09-08 23:38:41
      handler_name    : VideoHandle
    Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 123 kb/s (default)
    Metadata:
      creation_time   : 2013-09-08 23:38:41
      handler_name    : SoundHandle

ffmpeg -i aquarium.mp4 2>&1 | grep bitrate: | awk '{print $6}'

A few days ago I found very useful solution (thanks for Biomathematicus!) for deleting tables from a MySQL schema. I know that it could be quite difficult for some developers (also for me) to manually remove every table from schema without removing this schema itself. So, there is a two-step solution which is going to help you removing a lot of tables from SQL database.

1) List all tables in the MySQL schema :

SELECT CONCAT('drop table ',table_name,'; ')
FROM information_schema.tables
WHERE table_schema = 'yourDatabaseName';

drop table table1; 
drop table table2;

I really really would like to share with a video of my participation on conference called "Confitura" in the year 2013.

Confitura is the largest free conference for Java developers in Europe and even the largest event of its kind in Poland. 6 July this year on the campus of the University of Warsaw will be the next edition of our conference. From year to year we develop and we host a growing number of enthusiasts programming, a year ago there were more than 800. This year we expect nearly 1,000 people, for whom we have prepared five parallel tracks of almost 30 lectures.

More information you can find on : http://2013.confitura.pl/

Video : http://www.youtube.com/watch?v=HAuVAgeBqyQ



You can see when I am talking a lot of about many interesting and clever things starting from 0:34 second of this video ;) Enjoy.

I used to have a problem while I was developing some application using Django (Python Web Framework). This problem occurs when I received some data from some kind of source using for example JSON notation. When this data contains some custom characters which should be saved in Unicode notation, I received and error like this one :

Few days ago I had pleasure to install on my web server called XAMPP delivered by Apache Friends one of the management tool for PostgreSQL called PhpPgAdmin. I must to say that installation is very easy, all you have to do is to put extracted files of this tool to htdocs folder, edit config located on phpPgAdmin/conf/config.inc.php and just run index.php through your web browser.

Unfortunately in my case there was some issue with connecting to PostgreSQL database. I had message something like "Login disallowed". I spent a lot of time to figure out the right solution, which I am going to share with you.

Just go to file on this path - phpPgAdmin/conf/config.inc.php and just change

$conf['extra_login_security'] = true

$conf['extra_login_security'] = false

In the last days I was working on project which used one of the most powerful Javascript library jQuery in version 1.4.4. Yes, I know this version of jQuery is quite outdated. So, we decided to change it into jQuery 1.6.1. We expected some problems with change of library version, but what we discovered during looking for application errors was the change of handling of attributes and DOM object properties. I mean change function .attr to .prop

Before when we used jQuery 1.4.4 it was :

        
        
        
    
    
        
            Element 0
            Element 1
        
        Get property index
    

        
        
        
    
    
        
            Element 0
            Element 1
        
        Get property index