Digital audio formats on the network


Free Download Mp4Gain
picture

Digital audio formats on the network:

WAV: Waveform files (or simply wave) are the most common sound formats on Windows platforms. WAV files can also be played on Mac and other systems with player software.

MPEG (MP3): The Motion Pictures Experts Group (MPEG) format is a standard format with significant compression capability. MPEG level 3 or MP3 files are frequently used for web music distribution. However, due to their size, MPEG files must be downloaded completely before playing them.

RealAudio (.rm): Real Audio is the technology that currently predominates on the Web. You need a proprietary player, but the basic versions of the player are available for free.
MIDI: The Musical Instrument Digital Interface format is not a digital audio format. It represents notes and other information so that music can be synthesized. MIDI has good support and its files are very small, but it is only useful for certain applications because of the quality of its sound when played on PC hardware.

AU: The u-law format is one of the oldest sound formats on the Internet. Players are available for almost all platforms.

RMF: The Rich Music Format supported by Beatnik (www.beatnik.com) is a high quality audio format, primarily for “download-and-play”, which is becoming increasingly popular.

AIFF: The Audio Interchange File Format is very common on Macs. It is widely used in multimedia applications, but it is not very common on the Web.

Flac: Free Lossless Audio Codec (FLAC) (Lossless audio compression codec) Ogg project format without loss. The initial file can be completely recomposed with the disadvantage that the file occupies much more space than would be obtained when applying lossy compression or Lossy.

Digital audio on the network:

The digital sound is measured by the sampling frequency, or how many times the sound is digitized over a certain period of time. The sampling frequencies are indicated in kilohertz (kHz), which indicate the number of times the sound is sampled per second. The CD sound quality is obtained with 44.1 kHz, or 44,100 samples per second. For stereo sound, two channels are required, each 8 bits; At 16 bits per sample, this results in 705,600 bits of data on a CD, producing high quality sound, at the request of the end user. In reality, the transmission of this amount of data would occupy almost half the bandwidth of the T1 network. As the average user of the Web does not have this bandwidth, another solution is necessary. One possible solution is to decrease the sampling rate when digital sound is created for sending through the Web. A sampling frequency of 8 kHz, in mono, would produce acceptable results for simple applications, such as language, especially if we consider that the playback hardware generally consists of a combination of a simple sound card and a small speaker. Low quality audio does not require more than 64,000 bits of data per second, but the end user still has to wait to download the sound. Modern users need several seconds to receive, even in the best conditions, a single second of low quality sound, making continuous sound impossible.


Free Download Mp4Gain
picture


Mp4Gain Main Window
picture


Mp4Gain Features
picture


Free Download Mp4Gain
picture

Digital audio: a simple but deep explanation about digital audio. Part 1

Sound is a phenomenon that implies a propagation of waves generally produced by a vibratory movement of a body. The propagation of sound implies a transport of energy without carrying out a transport of matter.

digital audio

As the sound is produced by a wave movement when applying the Fourier transform we can express it by a sum of sinusoidal curves that correspond to pure tones that can be characterized by the magnitudes of any wave such as:

-Period It is the time elapsed between two equivalent points of a wave.
– Wavelength It is the real distance a wave travels from its highest point to the next equivalent point.
-Frequency It is the magnitude that measures the number of repetitions in a space of time.
-Amplitude It is the distance between the furthest point of the wave with the equilibrium point.

These magnitudes give the sound a series of characteristics such as:

-Duration: Determines the length or short of the sound due to the time, measured in seconds, it occupies.
-Intensity: Determines the high or low sound due to what we know in relative terms as volume, which is measured in decibels (it is a logarithmic scale).
-Timbre: Determines the proper nuance of each instrument or sound source due to the different harmonics that compose it.
– Hue: Determines the acute or serious sound due to the frequency it has. The frequency is measured in hertz (Hz).

If we carefully consider it, we will see that the initial concept of Mp3Gain was intensity, which is measured in decibels and represents the loudness we perceive.

digital audio

Digital audio

Digital audio is the digital coding of an electrical signal that represents any sound wave. This electrical signal is picked up for example by a microphone, which takes the sound whose nature is analog and transforms it into electricity that still has the same type of analog nature, then through the necessary hardware and software it can be transformed into binary information, turning Something continuous in discreet. This process involves two tasks: sampling and digital quantification of the electrical signal.

Within the digital audio there are different types of formats to represent the audio:

-PCM: They contain all the information received from the analog to digital converter, without any omission of data. This makes the type of formats that have the best quality in the digital world. WAV is an example of this type of format in question.

-Compressed: It is similar to the previous one, but specific compression techniques are used in which “non-essential” information can be lost to reduce the size of the final file. They usually have good quality in relation to the weight of the file, but as noted above, information is lost, so those with sufficiently developed / trained ears might perceive that there is something strange in a song for example. On the one hand we have formats such as MP3 and OGG that compress with loss, compared to FLAC that compresses without loss. Obviously between one format and the other there is a notable difference in the size of the final file.

-Descriptive: They are used primarily to make music and contain mainly a description of what would be the “score” of the song. With this description, the algorithm, which reproduces the song, can take a sound source with samples of the instruments that the composition needs, to synthesize the final sound based on the indications of the “score”. Examples of this format are MIDI and tracker formats (MOD, XM, IT, etc.). The difference between MIDI and tracker formats is that the latter bring built-in sound sources into the file, so the final file weighs more than using MIDI. However, with MIDI we will need to obtain a sound source on our own or use the one that brings the default sound card (which is not usually too good).