102 lines
2.4 KiB
Markdown
102 lines
2.4 KiB
Markdown
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Some possible API concepts for dealing with files
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=================================================
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Notes
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-----
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* requires libflac for flac decoding
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Use Cases
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---------
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* Play a file through the speakers
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* Use a file as input to an AudioNode for processing
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* Read a file into an array
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* Write an array into a file
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* Write the output of an AudioNode to a file
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IOStream API
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------------
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* users use standard julia "open" function to create an IOStream object
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* FilePlayer <: AudioNode takes an IOStream and uses `sf_open_fd` to open and
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play
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* play(io::IOStream) creates a FilePlayer and plays it (just like ArrayPlayer)
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* FileStream
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### Play a file through the speakers
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sndfile = open("myfile.wav")
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play(sndfile)
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close(sndfile)
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### Use a file as input to an AudioNode for processing
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sndfile = open("myfile.wav")
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# maybe FilePlayer also takes a string input for convenience
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node = FilePlayer(sndfile)
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mixer = AudioMixer([node])
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# etc.
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### Read a file into an array
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# TODO
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### Write an array into a file
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# TODO
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### Write the output of an AudioNode to a file
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node = SinOsc(440)
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# ???
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Separate Open Function API
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--------------------------
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* users use an explicit `af_open` function to open sound files
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* `af_open` takes mode arguments just like the regular julia `open` function
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* `af_open` returns a AudioFile instance.
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### Play a file through the speakers
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sndfile = af_open("myfile.wav")
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play(sndfile)
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close(sndfile)
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or
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play("myfile.wav")
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### Use a file as input to an AudioNode for processing
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sndfile = af_open("myfile.wav")
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# FilePlayer also can take a string filename for convenience
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node = FilePlayer(sndfile)
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mixer = AudioMixer([node])
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# etc.
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### Read a file into an array
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sndfile = af_open("myfile.wav")
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vec = read(sndfile) # takes an optional arg for number of frames to read
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close(sndfile)
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### Write an array into a file
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sndfile = af_open("myfile.wav", "w") #TODO: need to specify format
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vec = rand(Float32, 441000) # 10 seconds of noise
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write(sndfile, vec)
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close(sndfile)
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### Write the output of an AudioNode to a file
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sndfile = af_open("myfile.wav", "w") #TODO: need to specify format
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node = SinOsc(440)
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write(sndfile, node, 44100) # record 1 second, optional block_size
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# note that write() can handle sample depth conversions, and render() is
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# called with the sampling rate of the file
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close(sndfile)
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