[Audio]
The voice that the ears can hear is at 20Hz ~ 20 kHz
SonicIt is called audio.
[Sampling frequency]
That is, the sampling frequency, which refers
Number of times a sound sample is obtained per second. The higher the sampling frequency, the better the sound quality, and the more authentic the sound is. However, at the same time, it occupies more resources than the others. Because the resolution of human ears is very limited, it cannot be determined at a too high frequency.
The sampling frequency of 22050 is frequently used, and 44100 is the CD sound quality. The sampling frequency of more than 48000 or 96000 is meaningless to human ears. This is similar to the principle of 24 frames per second for a movie.
For example, if it is a dual-channel (STEREO), the dual copy is used, and the file size is almost doubled.
[Number of samples]
That is
Signature ValueOr sample value (that is, quantize the sample amplitude ). It is used to measure the number of audio fluctuations, or the resolution of the sound card. The larger the value, the higher the resolution, and the stronger the sound.
Each sample data records the amplitude, and the accuracy of the sample depends on the size of the number of digits of the sample:
- 1 byte (8 bit) can only record 256 records, that is, it can only divide the amplitude into 256 levels;
- 2 bytes (that is, 16 bit) can be subdivided into 65536 numbers, which is now the CD standard;
- 4 bytes (that is, 32 bit) can segment the amplitude to 4294967296 levels. Is it necessary.
[Number of channels]
That is
Number of sound channels. It is often divided into single-channel and stereo sound. The single-channel sound can only use one speaker to sound (some also process two speakers to output the same sound channel ), stereo Sound can make both speakers speak (generally there is a division of labor in the left and right audio channels), better space effect, of course there are many other channels.
[Frame]
Frame records
Sound UnitThe length is the product of the sample length (number of digits of the sample) and the number of channels.
[Cycle]
Audio Device
Number of frames required for one ProcessingThis is the unit for audio device data profiling and storage of audio data.
[Staggered mode]
Digital Audio Signal storage method. Data
Sequential frame storageFirst, record the left and right channels of frame 1, and then start the record of Frame 2...
[Non-staggered mode]
The first record is the left-channel sample of all frames within a cycle, and then all right-channel samples are recorded.
Bit Rate]
Transmission Rate per second(Bit rate, also called bit rate ). For example, 705.6 kbps or 705600bps, where B is bit, PS indicates the capacity of 705600bit per second.
Audio attributes (including the sampling rate, number of channels, digits, bit rate, and frames)
