The importance of codecs
Everything that has been written about the bit rate is valid
“with the same codec”, ie with the same algorithm
Coding, but the quality of the algorithms is very variable,
since the perception model, fundamental control of the levels of
compression.
Those who are best able to mimic natural perception will get it
the best results since the cutoff frequencies will be
least audible and significant, while a codec with a perceptual model
Unrealistic creates flat and empty passages of important frequencies.
In addition, a bad codec easily introduces “artifacts”; or
Sounds that are not available in the original originate from poor quantization
of some frequencies, especially if the original is not perfect.
Like most things in the computer world, codecs are evolving
In addition to the codec type, it is important that it is current and updated
for increasingly powerful algorithms.
Codecs fall into two categories: “fast”
and slow “. The most important fast codecs include blade,
QDesign and Xing, fast compression, but low to medium quality,
among the slow but high quality Fraunhofer and Lame are these
latest free and especially valid for high bit rates.
You can achieve good results with Fraunhofer coding
Most listeners cannot do this even at 128 Kbit / s and 320 Kbit / s
Distinguish MP3 from the original while compressing with Xing
o Blade with 128 Kbit / s can detect obvious artifacts and only with 256 Kbit / s
Audio reaches the quality of an MP3 compressed with 128 Kbit / s
Fraunhofer.
The just released Xing algorithm had the advantage of lower costs
Rights compared to Fraunhofer and faster coding speed
(It was also the first to implement variable bit rate VBR coding), but
Today’s processor performance is like that. for this
Factor is less important.
The lame algorithm has the advantage that no fees have to be paid
and of remarkable quality, especially at high bit rates – an MP3 from
128 Kbit / s encoded with Lame are less than one compressed with Fraunhofer.
but significantly better than Xing, and 256 Kbit / s Lame has the same quality
Fraunhofer.
At the moment, Lame is the best option for those who
You can afford larger files, while those that need to be careful
about the size, maybe because they have to offer files on an amateur website
or because they have an MP3 player with limited memory, they can pay well
Get a Fraunhofer encoder.
Xing, Blade, and other faster algorithms are not recommended, though
Pay attention to quality.
General quality and bit rate considerations
So that most listeners are of acceptable quality,
using a quality codec like Fraunhofer the bit rate that is normally used
(128 kbps, 1 MB per minute) is usually sufficient, especially if
Songs have a limited frequency range.
For some traces or for more sensitive ears a
highest bit rate, e.g. B. 256 Kbit / s (2 MB per minute, 1/5 of
Corresponding WAV).
64 kbit / s bit rates are always insufficient and with low quality codecs
like Xing or Blade are practically unknown.
Finally, we have to dispel a false myth: it is not possible to point it out
Music genres that need a higher bit rate, classical music too
Sometimes it can be made acceptable at 128 kbps because
Use restricted frequencies, while some rock or pop songs can
suffer because synthesizer tones and human voices are
easily exposed to the “artifact” effect.
Only lyrical music that has always been the most difficult
play and jazz (with cymbals,
Artifacts easy to suffer) certainly not suitable for MP3 and require bit rates
higher.
However, the results vary from song to song and are not
possible to give a general rule. It must be remembered that the audiophile,
The hi-fi musician or hobbyist can almost always
Distinguish an MP3 file with 320 Kbit / s from the original on the audio CD.
So if you have storage space, WAV files or codecs without loss of information
like WMA9 Lossless or FLAC (Free Lossless Audio Codec) always have a quality
Consider MP3, even if they are two to four times larger than
an MP3 with 320 Kbit / s.
