NorQualizer V1.50 GTK GUI - 2020 - V.Portet
* PURPOSE:
NorQualizer is a smart self-adaptative equalizer / normalizer which operates on multimedia files
for audio processing, in a way that they all sound as similar in terms of audio spectrum and volume level.
It is easily launched by a simple command line.
Especially useful for preparing audio CDs and audio MP3 libraries, NorQualizer prevent the listener
from having to do annoying equalization and volume ajustements each time that he plays a new audio track.
NorQualizer is not intended to be an audio FX generator but a true physiological normalizer which not
only adjusts the volume level. Its use is much faster than manual edition means that can be used for
equalizing and normalizing series of audio files.
This GTK version hs a graphical interface while previous versions of NorQualizer were command line utilities.
* INSTALL:
Pre-requisites:
* libgtk2.0-dev installed
* pkg-config installed
* ffmpeg installed
* LAME installed (to use MP3 re-encoding)
Compilation can easily be made by launching the provided script:
./build.sh
The executable file "norqualgui" can then be moved, as well as the "norqualizall" shell script (made
executable) in /usr/local/bin/ or ~/bin/
* USE of norqualizer:
Button "PROCESS" allows to select one single multimedia file to be processed.
Button "PROCESS FOLDER" allows to process all the multimedia files present in the folder to be selected
The checkboxes allow the following options:
- Encode / re-encode the final result to MP3.
Anyway at least a WAV file will be generated (to be prefered for audio CD burning).
- Reduces bass profile. To be used only for tracks having no bass line nor beats at all.
- Activates the click and pop discriminator in case where soundtracks have been extracted from vinyl records.
(In this case clicks and pops are not taken into account for normalization because they can be clamped.
Note that clips and pops are not removed. This is not the purpose of NorQualizer.)
- Select 224/192k in case where MP3 re-encoding is used
- Create a log file during the process
NB: For MP3 re-encoding LAME must be installed.
* TIPS:
The less conversions are done, the better final quality will be. Therefore if the audio track has to
be extracted for example from an FLV file, directly use the FLV as input file.
For the same reasons, when burning an audio CD use the "norqualized" WAV file instead of using the
MP3 one. (Else it will be discretely converted back to WAV-like format by the burning software).
* FAQ (Or: Possibly asked questions)
- My source file has volume level variations resulting from an annoying dynamic compression caused
by improper recording conditions. What can I do ?
Norqualizer cannot solve that kind of problem, and this will even disturb it when trying to
analyze the acoustic perception of the audio track.
You must first use "WAV audio compressor" ( http://sourceforge.net/projects/compressor/ ) called
with this parameters (re-compression with fast attack and decay time):
"compress my_extracted_file.wav 15 8 4" will return "Cmy_extracted_file.wav"
Then launch: norqualizer Cmy_extracted_file.wav
Note that anyway it will never be possible to recover the track as "hi-fi" in that case...
(It will sound quite like an FM radio recording)
- My source file has clipped audio signals which causes ugly crackling. What can I do ?
Unfortunately, you can do nothing.
- I processed a terribly trebbleless audio track. The result is better but trebbles sound bad,
metallic, or almost scratchy.
In case of drastically attenuated high frequencies (eg. low encoding bitrate in source file), it
will never be possible to recover them correctly, by any existing way.
- Can norqualizer be used to correct stereo asymetries ?
Yes, it does. Especially for recordings from cassette tapes where channels are often different in
terms of volume and bandwidth. It will not alter true stereo quality since it does not compress
and usual true stereo recordings are not based on bass/trebble discrimination.
- When I "norqualize" WAV files recorded from analog audio inputs, the "norqualized" file has no
more trebbles at all !
Probably you recorded from your analog source with improper parameter settings for your recording
software (eg. 32 bits format with a 16 bits input). This has resulted in a right-left swap on each
sample, causing a very high amplitude unaudible high frequency component in your soundtrack. Note
that anyway you must solve this problem to keep your amplifier and tweeters in good conditions,
whatever you use or not norqualizer. You can check for this in an audio editor (e.g. Audacity)
by zooming on a very small part of the track.
- Does norqualizer uses some psycho-acoustic well known theories, as used in MP3 algorythms ?
No. Norqualizer performs a time domain peak and quasi-peak analysis on 3 channels containing
prefiltered bands (Low, medium and high). Considering this levels monitored on the whole track,
it applies a correction factor for each channel before re-mixing. This level analysis principle
results from experience and observation and has not been justified by any theoretical work,
although the use of quasi-peak detection as one of the normalization criteria could be compared
to one of the well known perception phenomenons explained by theories of psycho-acoustics.
V.P. Paris, FR.
vincentportet_95@hotmail.com
Version 1.50 GTK Linux of the 30th of November 2020
