What's the difference between MP3 and AAC?

MP3 takes advantage of the insensitivity of human ears to high-frequency sound signals, converting time-domain waveform signals into frequency-domain signals, and dividing them into multiple frequency bands. Different compression rates are adopted for different frequency bands, which improves the compression rate for high-frequency signals (even ignores the signals) and adopts a small compression rate for low-frequency signals to ensure that the signals are not distorted.

AAC adopts a brand-new algorithm for coding, which is more efficient and more cost-effective. Using AAC format, people can feel that the sound quality is getting smaller without obvious reduction.

2. Different audio quality

The performance of AAC format at 96Kbps exceeds that of MP3 format at 128Kbps. The same is 128Kbps, and the sound quality of AAC format is obviously better than that of MP3. AC is the only network broadcast format that can get "excellent" in all EBU audition test items.

3. Different coding systems

Because MP3 is a lossy compression format, it provides various "bit rate" options-that is, it is used to represent the number of bits of encoded data required for audio per second. Typical speeds are between 128kbps and 320kbps(kbit/s).

In contrast, the uncompressed audio bit rate on CD is1411.2 kbps (16 bits/sampling point × 44 100 sampling point/second× 2 channels). MP3 files encoded at lower bit rates usually have poor playback quality. If the bit rate is too low, "compression noise" (sound not found in the original recording) will appear during playback.

References:

Baidu encyclopedia -AAC

Baidu Encyclopedia -MP3