Edge speed table

All About Edge/Gprs multislot classes

When buying a phone with GPRS/EDGE modem, you have to have a clear idea on the GPRS/EDGE multi classes. There are 17 classes in GPRS/EDGE system. If your requirement is basic you can go with GPRS/EDGE Class 10. If you need something to do with content uploads, class 10 will not sufficient, you need either Class 12/11/32/33 or 34. Ideally for uploads Class 12 is the cost effective option. You will get a clear picture on which model to choose on the basis of the tables below.  Most of the websites explain the speed of GPRS / EDGE in Time Slots. One Time Slot is equal to 59.2 Kilo Bits. Based on this calculation there are 3 tables.

  1. Timeslot table
  2. Kilobits table
  3. Kilobytes table

GPRS/EDGE Timeslot table

Multislot Class Downlink TS Uplink TS Active TS
1 1 1 2
2 2 1 3
3 2 2 3
4 3 1 4
5 2 2 4
6 3 2 4
7 3 3 4
8 4 1 5
9 3 2 5
10 4 2 5
11 4 3 5
12 4 4 5
30 5 1 6
31 5 2 6
32 5 3 6
33 5 4 6
34 5 5 6

GPRS/EDGE Kilobits table

Bandwidth is measured in Kilobits always. Eight bits are one byte. So if your ISP offer you a 1 MBPs speed, it means that you will get a download rate in 1024 divided by 8, which is 128 KiloBytes.

Multislot Class Downlink/Kbits Uplink/Kbits Active/Kbits
1 59.2 59.2 118.4
2 118.4 59.2 177.6
3 118.4 118.4 177.6
4 177.6 59.2 236.8
5 118.4 118.4 236.8
6 177.6 118.4 236.8
7 177.6 177.6 236.8
8 236.8 59.2 296
9 177.6 118.4 296
10 236.8 118.4 296
11 236.8 177.6 296
12 236.8 236.8 296
30 296 59.2 355.2
31 296 118.4 355.2
32 296 177.6 355.2
33 296 236.8 355.2
34 296 296 355.2

EDGE/GPRS Kilobytes table

If you download something over internet, your browser (such as Firefox / Chrome / internet explorer etc. ) will show the file transfer rate in Kilobytes.

Multislot Class Downlink KBytes Uplink Kbytes Active Kbytes
1 7.4 7.4 14.8
2 14.8 7.4 22.2
3 14.8 14.8 22.2
4 22.2 7.4 29.6
5 14.8 14.8 29.6
6 22.2 14.8 29.6
7 22.2 22.2 29.6
8 29.6 7.4 37
9 22.2 14.8 37
10 29.6 14.8 37
11 29.6 22.2 37
12 29.6 29.6 37
30 37 7.4 44.4
31 37 14.8 44.4
32 37 22.2 44.4
33 37 29.6 44.4
34 37 37 44.4

FFmpeg / MEncoder commands

FFmpeg is a BIG tool inn video editing. With FFmpeg, you can split / cut / join / convert your videos with just commands in the text console. Many video converting / editing software using FFmpeg and Mencoder in their back-ends. Hers is some useful ffmpeg / mencoder commands which I used so many times earlier.

How to convert avi format to mpg format with mencoder

mencoder input.avi -of mpeg -ovc lavc -lavcopts vcodec=mpeg1video -oac copy other_options -o output.mpg

How to combine two avi files to single avi file using mencoder

mencoder -forceidx -ovc copy -oac copy -o file.avi p1.avi p2.avi
mencoder -forceidx -ovc copy -oac copy -o myfilename.avi \home\tom\Documentries\Movies\converted\cvt_VTS_01_1.avi \home\tom\Documentries\Movies\converted\cvt_VTS_01_2.avi

How to cut an avi file using mencoder

mencoder -ss 00:00:20 -endpos 00:00:50 -ovc copy -oac copy bigvideo.avi -o result.avi

To Rip VCD to .avi

ffmpeg, ffmpeg -i yourVCD.dat -y output.avi

To cut an mp3 file

ffmpeg -acodec copy -ss 00:00:31 -t 00:01:00 -i input.mp3 out.mp3

To convert wmv to flv

ffmpeg -i sourceFile.wmv -sameq -acodec libmp3lame -ar 22050 -ab 96000 -deinterlace -nr 500 -s 640x480 -aspect 4:3 -r 20 -g 500 -me_range 20 -b 270k -deinterlace -f flv -y DestinationFile.flv

To split from vob to mp4 without losing quality

ffmpeg -i sourcdFile.vob -sameq -ss 00:00:02 -t 42 DestinationFile.mp4
ffmpeg -i sourcdFile.vob -sameq -ss [start time] -t [total seconds] DestinationFile.mp4
eg: ffmpeg -i \home\tom\TVCs\One.VOB -sameq -ss 00:00:02 -t 32 \home\tom\TVCs\Two.mp4

To convert from mp4 to wmv

ffmpeg -i \home\tom\tomLog4\WEB_0386.MP4 -sameq \home\tom\wmv\WEB_0386.wmv

To convert from mp4 to mpg

ffmpeg -i E:\tomLog4\100VIDEO\WEB_0386.MP4 -sameq \home\tom\movies\WEB_0386.mpg

To convert mp3 file to video with jpg frame

ffmpeg -f image2 -loop_input -i pic.jpg -i pic.mp3 -vcodec mpeg1video -qscale 2 -acodec copy -shortest newvideo.avi

To join three .mp3 files

ffmpeg -i concat:"File1.MP3|File2.MP3" -acodec copy File_Joined1.mp3
ffmpeg -i concat:"File_Joined1.mp3|File3.MP3" -acodec copy File_Joined2.mp3

FFmpeg official site | MEncoder official site

Ubuntu problem rectified.

Last Sunday evening, I was checking some photographs in my SD card in my Ubuntu 11.10 Dell laptop. After 20 minutes the battery backup indicated too low and I got the red signal warning. So that I was about to shutdown the system using the tty commandline “shutdown -h now”. But the “u” key did not work. Q,R,T keys also were not functioning correctly. In stead of giving the assigned characters, those keys were printing some numeric values on monitor. Initially I thought this may be something related with keyboard assembly, so that keyboard assembly should be replaced soon. Then I reboot the system using cntrl+alt+del. The same problem repeated after I logged in to the graphical terminal. Then I reboot the system, and logged in the tty. To my surprise, all the keys were working properly. But whenever I log into the graphical terminal the same problem repeats.
What should be the problem, anyone guess?
It was silly. It was not the problem of keyboard assembly, nor keyboard layout. And what? It was nothing but the user profile was corrupt. I renamed the home folder of the current user and logged in again, all the keys started working fine. It took more than 2-3 hours to find the real issue. In my experience silly issues like profile-related problems may consume more time to identify than complicated problems.

The Malayalam font related issues in GNU/Linux systems

This is a story about four people named Everyone, Someone, Anyone and No-one. There was an important job to be done and Everyone was expected to do it. Everyone was sure Someone would do it. Anyone could have done it, but No-one did it. Someone got angry about it because it was Everyone’s job. Everyone thought Anyone could do it, but No-one realised that Everyone wouldn’t do it. It ended up that Everyone blamed Someone when No-one did what Anyone could have done.

Fixing the issues are everyone’s job. And there are so many issues are there with GNU/Linux systems that handles Malayalam Unicode and so called ASCII / ISCII fonts. Most people in Kerala who use Malayalam fonts suffers this issue. Majority publishing houses and newspapers still use the non-standard ASCII fonts. This ASCII Fonts are nothing but a gimmick done in the ISO/IEC 8859-1 code table.  This code table handles the complex characters in Latin script.  What ASCII Malayalam font does is really funny – it replaces Malayalam glyphs instead of the whole glyphs in the ISO/IEC 8859-1 code table! So the computer system identifies the text just as some junk characters in Latin script.  So what is ISO/IEC 8859-1 code table? Wikipedia says:

ISO 8859-1 was based on the Multinational Character Set used by Digital Equipment Corporation in the popular VT220 terminal. It was developed within ECMA, the European Computer Manufacturers Association, and published in March 1985 as ECMA-94, by which name it is still sometimes known. The second edition of ECMA-94 (June 1986) also included ISO 8859-2, ISO 8859-3, and ISO 8859-4 as part of the specification.

In 1985 Commodore adopted ISO 8859-1 for its new AmigaOS operating system. The Seikosha MP-1300AI impact dot-matrix printer, used with the Amiga 1000, included this encoding.

In 1992, the IANA registered the character map ISO_8859-1:1987, more commonly known by its preferred MIME name of ISO-8859-1 (note the extra hyphen over ISO 8859-1), a superset of ISO 8859-1, for use on the Internet. This map assigns the C0 and C1 control characters to the unassigned code values thus provides for 256 characters via every possible 8-bit value.

ISO-8859-1 is (according to the standards at least) the default encoding of documents delivered via HTTP with a MIME type beginning with “text/” (however the draft HTML 5 specification requires that documents advertised as ISO-8859-1 actually be parsed with the Windows-1252 encoding.) It is the default encoding of the values of certain descriptive HTTP headers, and defines the repertoire of characters allowed in HTML 3.2 documents (HTML 4.0, however, is based on Unicode). It and Windows-1252 are often assumed to be the encoding of text on Unix and Microsoft Windows in the absence of locale or other information, this is only gradually being replaced with Unicode encoding such as UTF-8 or UTF-16.

Currently various DTP tools including Scribus, GIMP etc does not support Unicode. Persons like me who use extensive Malayalam text regularly suffers a lot due to such huge issues. And Unicode itself has some disputes regarding the codepoints like zwj, zwnj, atomic chillu etc.

I am attaching a presentation done for a group discussion earlier in 2010. Some png files generated from Oo.Impress:

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

Malayalam Font issues in GNU/Linux systems

The presentation was planned to deliver in Malayalam. But the fact is that I could not present it properly in the discussion because the schedule was so tight so that I could not enough time to deliver my speech. Lets “Everyone” of us  join hands together to fix the issues the Unicode Malayalam.

Opening note

The word “Hacking” is not at all negative. If you check the word with wikipedia, following result will you get

Hacking may refer to:

Computer hacking, including the following types of activity:
Hacker (programmer subculture), activity within the computer programmer subculture
Hacker (computer security), to access computer networks, legally or otherwise
Computer crime
Illegal taxicab operation
Pleasure riding, horseback riding for purely recreational purposes
The act of stealing jokes
Hacking, an area within Hietzing, a municipal district of Vienna, Austria
Ian Hacking, Canadian philosopher of science

What I mean with hacking is based on computer security.

Hacking means finding out weaknesses in a computer or computer network and exploiting them, though the term can also refer to someone with an advanced understanding of computers and computer networks

As of what wikipedia says, I am not a hacker at all. But I try to learn about the weakness and powers of system security. Thats all. I am running a blog with same name in blogger also. Its address is: http://hackingtom.blogspot.com

This blog is a continuation of that blog. Kindly read on. Happy hacking.