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Bridges-Java
3.4.2
Bridges(Java API)
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Bridges-Java
3.4.2
Bridges(Java API)
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This class provides support for reading, modifying, and playing, audio waveform.
This class provides a way to represent an AudioClip (think of a .WAV file) in Bridges as waveforms.
An AudioClip can be composed of multiple channels: a stereo sound would be composed of 2 channels (Left and Right), a mono sound would be composed of a single channel. A 5.1 sound would be composed of 6 channels. When building an AudioClip from a file, the number of channels is taken from the file; some constructors have a numChannels that enables to pass the number of channels explicitly. If unsure, one can know how many channels are in an audio clip using getNumChannels().
Each channel is essentially a 1D signal. That is to say, it is an array of values that represent how far the membrane of a speaker should be from its resting position. The quality of the sound is controlled by two parameters: sampling rate and sampling depth.
Sampling rate tells how many positions per second are encoded by the AudioClip. It is expressed in Hertz. CD quality is 44100Hz; while walkie-talkies use 8000Hz. It is set automatically if read from a file; or it can be passed as the sampleRate parameter to some of the constructors. The sampling rate can be obtained from an AudioClip using getSampleRate().
The length of an AudioClip is expressed in number of samples. So if an AudioClip is composed of 16,000 samples with a sampling rate of 8000Hz, the clip would be 2 seconds long. The number of samples can obtained with getSampleCount(); it is set from a file or can be passed as the sampleCount parameter of some of the constructor.
The sampling depth indicates how many different positions the membrane can take. It is typically expressed in bits with supported values being 8-bit, 16-bit, 24-bit, and 32-bit. If a clip is encoded with a depth of 8 bits, the membrane can take 2^8 different position ranging from -128 to +127, with 0 being the resting position. The sampling depth is read from files or passed as the sampleBits parameter of the constructor. The sampling depth of an existing clip can be obtained with getSampleBits().
The individual samples are accessed with the getSample() and setSample() functions. The samples are integer values in the [-2^(getSampleBits()-1) ; 2^(getSampleBits()-1)[ range. The functions allow to specify for channel and sample index.
A tutorial is available at: https://bridgesuncc.github.io/tutorials/AudioClip.html
Public Member Functions | |
| AudioClip (int sampleCount, int numChannels, int sampleBits, int sampleRate) | |
| create an audio clip More... | |
| AudioClip (WavFile wavFile) throws IOException | |
| create an audio clip from a WavFile object More... | |
| AudioClip (String file) throws IOException | |
| create an audio clip from a File More... | |
| AudioClip (int sampleCount, int numChannels) | |
| create an audio clip More... | |
| int | getNumChannels () |
| returns the number of channels of the clip More... | |
| int | getSampleRate () |
| returns the sampling rate of the clip More... | |
| int | getSampleCount () |
| returns the number of samples in the clip More... | |
| int | getSampleBits () |
| returns the sampling depth. More... | |
| int | getSample (int channelIndex, int sampleIndex) |
| access a particular sample More... | |
| void | setSample (int channelIndex, int sampleIndex, int value) |
| change a particular sample More... | |
| String | getDataStructType () |
| String | getDataStructureRepresentation () |
Additional Inherited Members | |
 Protected Attributes inherited from bridges.base.DataStruct | |
| String | QUOTE = "\"" |
| Package Attributes inherited from bridges.base.DataStruct | |
| String | COMMA = "," |
| String | COLON = ":" |
| String | OPEN_CURLY = "{" |
| String | CLOSE_CURLY = "}" |
| String | OPEN_PAREN = "(" |
| String | CLOSE_PAREN = ")" |
| String | OPEN_BOX = "[" |
| String | CLOSE_BOX = "]" |
| bridges.base.AudioClip.AudioClip | ( | int | sampleCount, |
| int | numChannels, | ||
| int | sampleBits, | ||
| int | sampleRate | ||
| ) |
create an audio clip
| numChannels | the number of channels |
| sampleCount | the total number of samples |
| sampleBits | the bits per sample |
| sampleRate | the sampling rate (Hz, or cycles per sec) |
| bridges.base.AudioClip.AudioClip | ( | WavFile | wavFile | ) | throws IOException |
create an audio clip from a WavFile object
| bridges.base.AudioClip.AudioClip | ( | String | file | ) | throws IOException |
create an audio clip from a File
| file | name of the file (should be a Wave file) |
| bridges.base.AudioClip.AudioClip | ( | int | sampleCount, |
| int | numChannels | ||
| ) |
create an audio clip
creates an AudioClip with numChannels channels, sampleCount samples at 44100 Hz with a depth of 32 bits
| numChannels | the number of channels |
| sampleCount | the total number of samples |
| String bridges.base.AudioClip.getDataStructType | ( | ) |
Reimplemented from bridges.base.DataStruct.
| String bridges.base.AudioClip.getDataStructureRepresentation | ( | ) |
Reimplemented from bridges.base.DataStruct.
| int bridges.base.AudioClip.getNumChannels | ( | ) |
returns the number of channels of the clip
| int bridges.base.AudioClip.getSample | ( | int | channelIndex, |
| int | sampleIndex | ||
| ) |
access a particular sample
| channelIndex | the index of the channel that will be accessed (in the [0;getNumChannels()-1] range). |
| sampleIndex | the index of the sample that will be accessed (in the [0;getSampleCount()-1] range). |
| int bridges.base.AudioClip.getSampleBits | ( | ) |
returns the sampling depth.
The sampling depth indicates how many bits are used to encode each individual samples. The values supported are only 8, 16, 24, and 32.
All samples must be in the [-2^(getSampleBits()-1) ; 2^(getSampleBits()-1)) range. that is to say, for 8-bit, in the [-256;255] range.
| int bridges.base.AudioClip.getSampleCount | ( | ) |
returns the number of samples in the clip
The length of the clip in second is getSampleCount()/((double) getSampleRate())
| int bridges.base.AudioClip.getSampleRate | ( | ) |
returns the sampling rate of the clip
| void bridges.base.AudioClip.setSample | ( | int | channelIndex, |
| int | sampleIndex, | ||
| int | value | ||
| ) |
change a particular sample
| channelIndex | the index of the channel that will be accessed (in the [0;getNumChannels()-1] range). |
| sampleIndex | the index of the sample that will be accessed (in the [0;getSampleCount()-1] range). |
| value | the sample value (in [-2^(getSampleBits()-1) ; 2^(getSampleBits()-1)) range). |
1.9.1