What is the format of m4a (how to record it as an m4a file)
Talk about several commonly used audio formats.
What is a . WAV file?
File extension: . Sound Resource File
Format: No Compression No Loss
Waveform files (also known as WAV files) are a popular digital audio format that is the gold standard for studio recordings . WAV was one of the first digital audio formats and quickly became a staple across all platforms. Despite decades, it still maintains its status as one of the world’s leading professional audio formats.
WAV files capture and reconstruct the original audio waveform in higher quality without affecting or changing the sonic character of the sound in any way. WAV encodes the data using PCM (Pulse Code Modulation), chopping it up into small chunks to give the highest possible quality. It is a lossless file format, which means no data is lost. Thus, the closest mathematical/digital representation of the original audio waveform is captured and recorded, and no appreciable loss of audio quality occurs in the process.
WAV files are also uncompressed, which means that the data is stored in its full original format and does not require decoding.
What is it? AIFF files?
File extension: . aif or. aiff
Format: No Compression No Loss
AIFF (Audio Interchange File Format) works the same way: it provides studio-quality audio recording and playback. AIFF offers the same sample rate and bit depth options as WAV files. AIFF uses PCM to record audio waveforms into precise samples (slices) to provide higher audio recording quality and sound reproduction. Just like WAV, AIFF stores data in an uncompressed lossless format, meaning no quality is lost, just pure sound.
So what is the difference between the two? It mostly comes down to history. WAV was created jointly by Microsoft Windows and IBM, so WAV files can only be played locally on Windows computers. AIFF, on the other hand, was the Macintosh’s answer to WAV files, allowing full studio-quality audio recording and playback on Macs. Both formats can be natively recorded and played back on any operating system these days, so they’re easily interchangeable and provide the same high-quality audio regardless of format.
What is a .mp3 file?
File extension: .mp3
Format: Compressed and Lossy
Uncompressed audio formats such as WAV and AIFF can provide excellent sound quality, but The tradeoff is a larger file size. With the rise of Internet file sharing in the mid-1990s, people quickly realized that sending unsolicited files over dial-up connectionsCompressed files are impractical and often impossible. This is why MP3 (MPEG-2 Audio Layer 3) was born.
A three-minute song needs about 30MB to output in WAV or AIFF format, but converting it to MP3 only needs one-tenth of the empty space, about 3MB. Thanks to efficient compression algorithms, MP3 has become the main content of the Internet age and has maintained a strong position.
PS: Earlier everyone called all music players “MP3”. Say, “Did you buy an MP3?”
Like images, smaller audio files lose clarity and detail.
However, small files come at the expense of sound quality. Image taken above. On the left, you can vividly see every little wrinkle and color. However, the highly compressed image (on the right) becomes very pixelated and all sharpness and detail are lost (but the meaning of the picture is still understandable). The same happens when compressing audio files.
Different compression formats use different methods to re-encode data in a space-efficient manner. However, this method of saving empty means that some data is bound to be lost in the process. Usually the high frequency is one of the lost frequencies, because most people’s hearing can’t really hear the details in the high frequency. The lower the encoding quality, the more frequencies and details are lost in the audio.
Having said that, modern compression algorithms allow for higher bitrates, which in turn means that they can achieve high compression ratios with little noticeable loss in audio quality. Bit rate indicates the amount of data transmitted per second for audio content. The general rule of thumb is: smaller bitrate = smaller file size. So if you want to keep good quality but still take advantage of the easy sharing of MP3s, you need to keep bitrates above 128Kbps (thousands of bits per second).
What is an M4A/MP4 file?
File extensions: .m4a, .mp4
Format: Lossy compression
M4A (MPEG-4 Part 14) files are Apple’s answer to MP3 . This Mac-centric compressed audio format is often seen as the successor to MP3. With the birth of the iTunes Store, its popularity also increased. In the iTunes Store, M4A has become the main form of purchasing music through online music stores. It remains the preferred format for all audio contained in apps published on the Mac and iOS app stores, as well as on Nintendo and PlayStation products.
M4A files are encoded using the lossy Advanced Audio Coding (AAC) codec, which provides the same bitrate as MP3 but with better compression. This reduces file size and provides higher audio quality.
While many audio players can play on various platformsM4A files, but they are still not as compatible as MP3, which is why MP3 is still the most common one.