Posts Tagged ‘Convert’

Squid Proxy log timestamp human readable / Convert and beautify Proxy unixtime logs in human-readable form howto

Thursday, February 21st, 2019

Reading Time: 3minutes


If you have installed Squid Cache Proxy recently and you need to watch who is accessing the proxy and what Internet (website is viewed) under /var/log/squid/access.log /var/log/store.log /var/log/access.log etc., you will be unpleasently surprised the log's records are logged in a weird human unreadable format called UTC as Squid Proxy server does not store the date / year / hour time information in a human readable format.

Squid uses the format:
<UNIX timestamp>.<Centiseconds> and you have to be a robot of a kind or a math genious to read it 🙂

To display Squid Proxy log in a human readable, luckily you can use below one-liner  regular expression.

cat access.log | perl -p -e 's/^([0-9]*)/”[“.localtime($1).”]"/e'

If you have to review squid logs multiple times and on a regular basis you can either set some kind of cmd alias in $HOME/.bashrc such as:

alias readproxylog='cat access.log | perl -p -e 's/^([0-9]*)/”[“.localtime($1).”]"/e'

Or for those who prefer beauty install and use a log beatifier / colorizer such as ccze

root@pcfreak:/home/hipo# apt-cache show ccze|grep -i desc -A 3
Description-en: robust, modular log coloriser
 CCZE is a robust and modular log coloriser, with plugins for apm,
 exim, fetchmail, httpd, postfix, procmail, squid, syslog, ulogd,
 vsftpd, xferlog and more.

Description-md5: 55cd93dbcf614712a4d89cb3489414f6
Tag: devel::prettyprint, implemented-in::c, interface::commandline,
 role::program, scope::utility, use::checking, use::filtering,

root@pcfreak:/home/hipo# apt-get install –yes ccze


tail -f /var/log/squid/access.loc | ccze -CA

ccze is really nice to view /var/log/syslog errors and make your daily sysadmin life a bit more colorful


tail -f -n 200 /var/log/messages | ccze

tail-ccze-syslog-screenshot viewing in Colors your Linux logs

For a frequent tail + ccze usage with ccze you can add to ~/.bashrc following shell small function

tailc () { tail $@ | ccze -A }

Below is a list of supported syntax highlighting colorizer:

$ ccze -l
Available plugins:

Name      | Type    | Description
apm       | Partial | Coloriser for APM sub-logs.
distcc    | Full    | Coloriser for distcc(1) logs.
dpkg      | Full    | Coloriser for dpkg logs.
exim      | Full    | Coloriser for exim logs.
fetchmail | Partial | Coloriser for fetchmail(1) sub-logs.
ftpstats  | Full    | Coloriser for ftpstats (pure-ftpd) logs.
httpd     | Full    | Coloriser for generic HTTPD access and error logs.
icecast   | Full    | Coloriser for Icecast(8) logs.
oops      | Full    | Coloriser for oops proxy logs.
php       | Full    | Coloriser for PHP logs.
postfix   | Partial | Coloriser for postfix(1) sub-logs.
procmail  | Full    | Coloriser for procmail(1) logs.
proftpd   | Full    | Coloriser for proftpd access and auth logs.
squid     | Full    | Coloriser for squid access, store and cache logs.
sulog     | Full    | Coloriser for su(1) logs.
super     | Full    | Coloriser for super(1) logs.
syslog    | Full    | Generic syslog(8) log coloriser.
ulogd     | Partial | Coloriser for ulogd sub-logs.
vsftpd    | Full    | Coloriser for vsftpd(8) logs.
xferlog   | Full    | Generic xferlog coloriser.

At many cases for sysadmins like me that prefer clarity over obscurity, even a better solution is to just change in /etc/squid/squid.conf
the logging to turn it in human-readable form
, to do so add to config somewhere:


Logformat squid %tl.%03tu %6tr %>a %Ss/%03Hs %

You will get log output in format like:


18/Feb/2019:18:38:47 +0200.538 4787 y.y.y.y TCP_MISS/200 41841 GET – DIRECT/x.x.x.x text/html

SQUID's format recognized parameters in above example are as follows:


%    a literal % character
>a    Client source IP address
>A    Client FQDN
>p    Client source port
la    Local IP address (http_port)
lp    Local port number (http_port)
sn    Unique sequence number per log line entry
ts    Seconds since epoch
tu    subsecond time (milliseconds)
tl    Local time. Optional strftime format argument
default %d/%b/%Y:%H:%M:%S %z
tg    GMT time. Optional strftime format argument
default %d/%b/%Y:%H:%M:%S %z
tr    Response time (milliseconds)
dt    Total time spent making DNS lookups (milliseconds)


Converting .crt .cer .der to PEM, converting .PEM to .DER and convert .PFX PKCS#12 (.P12) to .PEM file using OpenSSL

Friday, September 1st, 2017

Reading Time: < 1minute


These commands allow you to convert certificates and keys to different formats to make them compatible with specific types of servers or software. For example, you can convert a normal PEM file that would work with Apache to a PFX (PKCS#12) file and use it with Tomcat or IIS.

  • Convert a DER file (.crt .cer .der) to PEM


    openssl x509 -inform der -in certificate.cer -out certificate.pem
  • Convert a PEM file to DER


    openssl x509 -outform der -in certificate.pem -out certificate.der
  • Convert a PKCS#12 file (.pfx .p12) containing a private key and certificates to PEM


    openssl pkcs12 -in keyStore.pfx -out keyStore.pem -nodes

    You can add -nocerts to only output the private key or add -nokeys to only output the certificates.

  • Convert a PEM certificate file and a private key to PKCS#12 (.pfx .p12)


    openssl pkcs12 -export -out certificate.pfx -inkey privateKey.key \
    -in certificate.crt -certfile CACert.crt

How to add (.srt , .sub) subtitles to .flv flash movie video on Linux

Friday, April 15th, 2011

Reading Time: 2minutes

If you're on Linux the questions like, how can I convert between video and audio formats, how to do photo editing etc. etc. have always been a taugh question as with it's diversity Linux often allows too many ways to do the same things.

In the spirit of questioning I have been recently curious, how can a subtitles be added to a flash video (.flv) video?

After some research online I've come up with the below suggested solution which uses mplayer to do the flash inclusion of the subtitles file.

mplayer your_flash_movie.flv -fs -subfont-text-scale 3

While including the subtitles to the .flv file, it's best to close up all the active browsers and if running something else on the desktop close it up.
Note that above's mplayer example for (.srt and .sub) subtitle files example is only appropriate for a .flv movie files which already has a third party published subtitle files.

What is interesting is that often if you want to make custom subtitles to let's say a video downloaded from Youtube on Linux the mplayer way pointed above will be useless. Why?

Well the Linux programs that allows a user to add custom subtitles to a movie does not support the flv (flash video) file format.

My idea on how to create custom subtitles and embed them into a flv movie file is very simple and it goes like this:

1. Convert the .flv file format to let's say .avi or .mpeg
2. Use gnome-subitles or subtitleeditor to create the subtitles for the .avi or .mpeg file
3. Convert back the .avi/.mpeg file with included subtitles to .flv (flash video format)

This methodology is really long and time consuming, but pitily as far as my understanding goes it's the only way to do that on your Linux until now.

To make the conversations between .flv and .avi format you will need to use the ffmpeg – (FFMpeg command line tool video converter), here is how:

– Convert .flv to .avi

debian:~# /usr/bin/ffmpeg -i input_flvfilename.flv output_avifilename.avi

– Convert .avi file to .flv

debian:~# /usr/bin/ffmpeg -y -i /path/to/your/avi/input_avifilename.avi -acodec mp3 -ar 22050 -f flv

The required overall tools which you will have to have installed on your Debian or Ubuntu Linux are:

1. ffmpeg
2. gnome-subtitles
3. subtitleeditor
4. mplayer

You will also have to spend some time to get to know gnome-subtitles or subtitleeditor, but it won't be that long until you get the idea on how to use them.

Convert png files to ico on Linux – Create “icon” files from pictures

Tuesday, November 2nd, 2010

Reading Time: < 1minute
You will need png2ico

First you will have to download the png2ico source

Now you will have to download compile and install the program by issuing:

debian:~# wget
debian:~# tar -zxvf png2ico-src-2002-12-08.tar.gz...
debian:~# cd png2ico/
debian:/root/png2ico# make
debian:/root/png2ico# cp -rpf png2ico /usr/local/bin/

Convertion is pretty easy and it comes to executing simply:

debian:/home/hipo$ png2ico favicon.ico png_picture_to_convert.png

Note that your png_picture_to_convert.png has to be in a graphic dimensions of 16×16
That’s all now you should have your favicon.ico on your Linux created.

Convert WAV to MP3 in command line with LAME on Linux

Friday, April 8th, 2011

Reading Time: < 1minute
I needed to convert a bunch of files from WAV to MP3 format on my Linux desktop.

I’ve placed all my wav files to the directory /home/hipo/wav

And then I issued the small one liner script to convert the .wav files to .mp3 using the niftly lame linux mp3 convertor.

Here is how I did it:

linux-desktop:~$ cd wav
linux-desktop:/home/hipo/wav$ for i in *.wav; do
new_name=$(echo $i |sed -e 's#wav#mp3#g');
lame -V0 -h -b 160 --vbr-new "$i" "$new_name";

After executing the little script you might go and have a coffee, if you have thousands of files, each file convertion takes about 10-15 seconds of time (speed depends on your CPU).

Here is some output from a lame convertion to mp3 taking place:

Encoding as 8 kHz single-ch MPEG-2.5 Layer III VBR(q=0)
Frame | CPU time/estim | REAL time/estim | play/CPU | ETA
27237/27237 (100%)| 0:12/ 0:12| 0:12/ 0:12| 155.89x| 0:00
64 [27237] ***************************************************************
kbps mono % long switch short %
64.0 100.0 84.1 8.9 7.0
If you want to save my convertion quickly for a later, download my Convert WAV to mp3 from a directory with lame shell script here

Actually there are plenty of other ways to convert wav to mp3 on Linux through mplayer, ffmpeg even with mpg123.

There are also some GUI programs that could do the convertion like winff , however for some weird reason after installing WinFF on my debian it was not able to complete convertion to mp3?!
But it doesn’t matter, the good news is I did what I wanted to via the simple lame program and the above script, hope it helps somebody out there.

Convert PDF .pdf to Plain Text .txt files on GNU / Linux and FreeBSD / pdftotext

Friday, November 16th, 2012

Reading Time: 2minutes

Convert PDF .pdf to .txt Plain Text on GNU / Linux Redhat, Debian, CentOS, Fedora and FreeBSD with pdftotext poppler-utils

If you need to convert Adobe PDF to Plain Text on Linux or FreeBSD, you will have to take a look at a poppler-utils – (PDF Utilities).

For those who wonder why you need at all a .PDF in .TXT, I can think of at least 4 good reasons. 

PDF to text convertion on Linux and other UNIX-es is possible through a set of tools called poppler-utils

poppler-utils is installable on most Linux distributions on Debian Ubuntu based Linux-es it is installable with the usual:

noah:~# apt-get install --yes poppler-utils

On Fedora it is available and installable from default repositories with yum

[root@fedora~]# yum -y install poppler-utils 

On Mandriva Linux:
[root@mandriva~] # urpmi poppler

On FreeBSD (and possibly other BSDs) you can install via ports or install it from binary with:

freebsd# pkg_add -vr poppler-utils

Here is a list of poppler-utils contents from the .deb Debian package, on other distros and BSD the /bin content tools are same.
noah:~ # dpkg -L poppler-utils|grep -i /usr/bin/

1. Converting  .pdf to .txt 

Converting whole PDF document to TXT is done with:

$ pdftotext PeopleWare-Productive_Projects.pdf PeopleWare-Productive_Projects.txt
2. Extracting from PDF to Text file only selected pages

 Dumping to .TXT only specific pages from a PDF file: is done through -f and -l arguments (First and Last) pages number.

$ pdftotext -f 3 -l 10 PeopleWare-Productive_Projects.pdf PeopleWare-Productive_Projects.txt

3. Converting PDF to TXT  protected with password

  $ pdftotext -opw 'Password' Password-protected-file.pdf Unprotected-file-dump.txt

the -opw arguments stand for 'Owner Password'. As suggested by man page -opw will bypass all PDF security restrictions. In PDFs there are file permission password protection as well as user password. 

To remove permissions password protection of file

$ pdftotext -upw 'Password' Password-protected-file.pdf Unprotected-file-dump.txt

4. Converting .pdf to .txt and setting type of end of file

Depending on the type of Operating System the TEXT file will be red further, you can set the type of end of lines (for those who don't know it here is the 3 major OSes UNIX, Windows, and MAC end of line codes:

DOS & Windows: \r\n 0D0A (hex), 13,10 (decimal)
Unix & Mac OS X: \n, 0A, 10
Macintosh (OS 9): \r, 0D, 13

$ pdftotext -eol unix PeopleWare-Productive_Projects.pdf

The -eol accepts (mac, unix or dos) as options

A bit off topic but very useful thing is to then listen to converted .txt files using festival.

5. Reading .PDF in Linux Text Console and Terminals

$ pdftotext PDF_file_to_Read.pdf -

Btw it is interesting to mention Midnight Commander( mcview ), component which supports opening .pdf files in console uses pdftotext for extracting PDFs and visualizing in plain text in exactly same way

Well that's it happy convertion.

Convert .doc to .pdf on Linux and BSD using console / Convertion of PDF to DOC inside scripts

Tuesday, November 13th, 2012

Reading Time: 4minutes

how to Convert .doc to .PDF using console / terminal on Linux and FreeBSD

On Linux, there are plenty of ways nowadays to convert Microsoft Word or OpenOffice .DOC documents to Adobe's PDF (Postscript). However most of the ways require a graphical environment. As I'm interested in how convertion is done mainly from console to suit shell scripts and php which has to routinely convert a bunch of .DOC files to .PDF. I've checked today how PDF to DOC is possible on Debian, Ubuntu, Arch Linux  and FreeBSD..

There are few tools one can use from console, that doesn't requiere you to have running Xorg on the convertion host. The quality of the produced converted document, may vary and with some Microsoft Office doc files, there might be some garbage. But generally for simplistic and well written "macros" free documents the quality of PDF is satisfactory with few of the tools.

Here I will list the few tools, one can use for convertion:

  • abiword – you probably know abiword GUI program which is a good substitute for people who doesn't want the huge openoffice on the host. interestingly abiword supports converts with no need for GUI
  • wvPDF (you have to have install wv package and usually this converter works well only with very old .DOC (MS Office 97) – I was not impressed with those convert results
  • oowriter / swriter (whether LibreOffice installed) or writer (on LibreOffice), on some Ubuntus and derivatives the equivalent cmd is lowriter
  • unoconv – this tool produces really good DOC to  PDF converts, it is a python script using openoffice / libreoffice as backend convertion engine so produced PDFs will be identical like the ones produced with oowriter, the pros of the tool is its syntax is very user friendly and along with PDF to DOC it supports easy syntax converting to  bunch of other file formats. Actually unoconv supports same convertions which supported by, the advantage is however you can use it within console and even schedule convertion to be processed by a remote host.


1. Convertion of DOC to PDF with abiword

abiword --to=pdf doc_file_to_convert.doc

2. Convert DOC to PDF with wvPDF

apt-get install --yes wv texlive-base texlive-latex-base ghostscript

wvPDF doc-file-to-convert-to-pdf.doc converted-to-pdf.pdf

wvPDF doc-file-to-convert-to-pdf.doc convert-to-pdf.pdf

Current directory: /home/hipo/Desktop
"doc-file-to-convert-to-pdf.eps" exists - skipping...
Some problem running latex.
Check for Errors in steinway.log


The produced .pdf was not useful most of the text inside was completely missing as well as some weird probably PostScript convertion characters were in the .PDF. Seeing its output I would as of time of writing wvPDF Debian's verion 1.2.4 is crap.

3. Convert DOC to PDF with oowriter / swriter / lowrite

a) convert with oowriter and swriter

I saw posts online claiming DOC to PDF convertion is possible directly with oowriter or swriters with commands:

oowriter -convert-to pdf:writer_pdf_Export input-doc-file-to-convert.doc


swriter -convert-to pdf:writer_pdf_Export steinway.doc - as named on some Linux-es

As long as I tested it on my Debian Squeeze, neither of the two works
.I saw some suggestions that PDF can be generated by installing and using cups-pdf debian package:

apt-get install cups-pdf oowriter -pt pdf your_word_file.doc b) convert DOC to PDF with lowriter I've seen in Ubuntu documentation and in Ubuntu forums, users saying they had some good results using lowriter, which is a sort of front-end program to ImageMagick's convert. I never tested that but I doubt of any satisfactory results, as I tried converting to PDF earlier using convert and often converts failed. Anyways you try it with:

lowriter --convert-to pdf *.doc


4. Converting PDF to DOC  with unoconv

As of time of writing it seemsunoconv is best Linux console tool for converting .doc to .pdf

It produces good readable text, as well as pictures and elements looks exactly as in OpenOffice.

To install it I run:

# apt-get install --yes unoconv

To use it:

$ unoconv -fpdf any-file-to-convert.doc

If you don't get errors or it doesn't crash a .doc file with same name any-file-to-convert.doc is created.

What unoconv, does is precisely the same as if using OpenOffice GUI's  to convert to PDF:


  • Open -> Open Office (3.2 in my case)
  • Open Document to export
  • File->Export as PDF
  • Click: Export
  • Choose file namefor output PDF

An interesting feature of unoconv is its possibility to run and convert as a port listening server. I never used this but noticed it mentioned in manual EXAMPLE section:


       You can use unoconv in standalone mode, this means that in absence of an OpenOffice listener, it will starts its own:

       unoconv -f pdf some-document.odt
       One can use unoconv as a listener (by default localhost:2002) to let other unoconv instances connect to it:

       unoconv --listener &
       unoconv -f pdf some-document.odt
       unoconv -f doc other-document.odt
       unoconv -f jpg some-image.png
       unoconv -f xsl some-spreadsheet.csv
       kill -15 %-
       This also works on a remote host:

       unoconv --listener --server --port 4567
       and then connect another system to convert documents:

       unoconv --server --port 4567

unoconv does not recognize wildcards like ' * ' , so in order to convert multiple DOC to PDF files one has to use the usual shell loop:

for i in *.doc; do unoconv -fpdf $i; done

From all my tests, I think unoconv is preferred tool for Linux and BSD users (good time to mention unoconv is available on FreeBSD too. BSD users can install it via port  /usr/ports/textproc/unoconv)

How to convert Adobe PDF file format to Microsoft Word DOC on MS Windows 2000 / XP / Vista / 7

Tuesday, July 24th, 2012

Reading Time: 2minutesHow to convert PDF to DOC on Microsoft Windows XP, MS Windows 7, Win Vista convert PDF to MS DOC 2003, ABBYY Covert Page
I had to convert Adobe PDF file to Microsoft Word ( .doc) file on Microsoft Windows OS for a friend. There is plenty of software available to convert PDF to DOC on Windows, as well as few web-site services claiming to convert correcly PDF to DOC. Converting PDF to DOC is easy and can be done with Open Office, however the reverse process is a real pain in the ass. I tried a dozen of free web serviecs to convert an ancient Latin writting PDF to DOC but none of them couldn’t properly convert it. Failing with the web services as a tool to convert, I’ve turned to seeking a tool that will do the trick. After trying few PDF to DOC converters which failed to produce a properly structed edittable DOC from the PDF file, I’ve come across ABBYY PDF Transformer 2.0. Abbyy PDF Transformer finally did it …

I’ve tried hard to look for a free software good PDF to DOC converter alternative for Windows but it seems as of time of writing this post there is no GPLed free software that does properly convert PDFs to MS WORD DOC ….

Using Abbyy PDF Transformer 2.0 is a piece of cake all I had to do is select the PDF file (pressing Open PDF) and then click on Convert (in right bottom corner). Below is a shot of Abby PDF transformer in action.

How to convert PDF to DOC on Microsoft Windows XP, MS Windows 7, Win Vista convert PDF to MS DOC 2003, abby pdf converter in action

Convert single PDF pages to multiple SVG files on Debian Linux with pdf2svg

Sunday, February 26th, 2012

Reading Time: 2minutes

In my last article, I've explained How to create PNG, JPG, GIF pictures from one single PDF document
Convertion of PDF to images is useful, however as PNG and JPEG graphic formats are raster graphics the image quality gets crappy if the picture is zoomed to lets say 300%.
This means convertion to PNG / GIF etc. is not a good practice especially if image quality is targetted.

I myself am not a quality freak but it was interesting to find out if it is possible to convert the PDF pages to SVG (Scalable Vector Graphics) graphics format.

Converting PDF to SVG is very easy as for GNU / Linux there is a command line tool called pdf2svg
pdf2svg's official page is here

The traditional source way compile and install is described on the homepage. For Debian users pdf2svg has already existing a deb package.

To install pdf2svg on Debian use:

debian:~# apt-get install --yes pdf2svg

Once installed usage of pdf2svg to convert PDF to multiple SVG files is analogous to imagemagick's convert .
To convert the 44 pages Projects.pdf to multiple SVG pages – (each PDF page to a separate SVG file) issue:

debian:~/project-pdf-to-images$ for i in $(seq 1 44); do \
pdf2svg Projects.pdf Projects-$i.SVG $i; \

This little loop tells each page number from the 44 PDF document to be stored in separate SVG vector graphics file:

debian:~/project-pdf-to-images$ ls -1 *.svg|wc -l

For BSD users and in particular FreeBSD ones png2svg has a bsd port in:


Installing on BSD is possible directly via the port and convertion of PDF to SVG on FreeBSD, should be working in the same manner. The only requirement is that bash shell is used for the above little bash loop, as by default FreeBSD runs the csh. 
On FreeBSD launch /usr/local/bin/bash, before following the Linux instructions if you're not already in bash.

Now the output SVG files are perfect for editting with Inkscape or Scribus and the picture quality is way superior to old rasterized (JPEG, PNG) images

Create PNG, JPG, GIF pictures / images from PDF on Linux

Saturday, February 25th, 2012

Reading Time: 2minutes

I've received a PDF file with a plan for development of a bundle of projects, My task was to evaluate this plan and give feeback on the 44 pages PDF document.

Since don't know of program to directly be able edit PDF files on GNU / Linux ?, my initial idea was to open and convert the PDF to ODT / DOC with OpenOffice (Libre Office) and then edit the ODT file.
Unfortunately Open Officeoowrite program was unable to open / visualize the PDF file. My assumption is OO failure to open the PDF is because the PDF was generated on Microsoft Windows with Adobe illustrator or smth.

The idea that came to my mind as alternative, way to edit the PDF file was to convert it in pictures edit and then convert the pictures to PDF.
In other words to follow these 3 steps:
1. Convert the PDF document to multiple images
2. Edit each of the images with GIMP or Inkscape
3. Convert back all images to a single PDF file

Some time ago, I've written an article how to create PDF file from many image files in JPEG, PNG or GIF on Linux

. This prior article was exactly describing how to complete Step 3.Therefore all left was to find a way to convert the PDF file to multiple JPEG / PNG / GIF images.

convert command to convert PDF document to multiple pictures which you can take from my earlier article is:

$ convert *.jpg outputpdffile.pdf
Actually in Step 1 I was aiming to do the opposite of what I've previously done.

Hence, in order to convert the singe Project.PDF file to multiple PNG images, I just switched convert IN / OUT arguments order.

hipo@noah:~/project-pdf-to-images$ convert Project.pdf Project.png

I've done the PDF to pictures conversion on my notebook running Debian Squeeze (6.0.2) GNU / Linux.Convertion of the PDF file to 44 images, took 25 seconds on my dual core 1.8 Ghz / 2GB RAM Thinkpad r61.
Afterwards, I've had at hand 44 PNG files generated, e.g.:

hipo@noah:~/project-pdf-to-images$ ls -al Project-*.png |wc -l

convert was also smart enough to produce correct file naming. The output file names were:

Nicely each number (-1.png) was corresponding to the respective PDF page. For instance Project-10.png was corresponding to page 10 of the Projects.PDF file

Rather ironically, after convertion of the PDF to pictures, while opening the Project-1.png, I've noticed The GIMP – (The GNU Image Manipulation Program) is capable of directly reading PDF files. GIMP has both the option to open files in layers or separate images 😉
Anyways even if GIMP is used to modify the different PDF pages as layers, once completed GIMP doesn't have the ability to save the file as PDF and therefore once saved the file if merging of layers is done the resulting picture becomes ONE BIG MESS.
Therefore it seems my the 3 steps way e.g.:

1. convertion PDF to pictures
2. picture edit with GIMP or Inkscape
3. convertion of pictures back to PDF

is still the only way to "modify PDF" in Linux or BSDs. I will be glad to hear if someone has come up with a better solution?