NodeJS module for streaming subsections of FLAC files
npm install flac-substreamNodeJS module for streaming subsections of FLAC files.
This module is intended to accompany the flac-seektable module.
``sh`
npm install flac-substream
The module returns a single function:
`javascript`
substream(
writable, // A stream.Writable object for the output
seekdata, // Metadata object from flac-seektable module
start, // Start position (index into seekpoints)
end, // End position (index into seekpoints)
get_read_stream // Function with signature: (start, end), must return stream.Readable
)
The get_read_stream function must return a stream.Readable object that provides data from the FLAC file from offset start to offset end.
`javascript
// Demonstrates the usage to perform random access on a file.
// This is by no means a practical example (most usecases would involve storage of the FLAC metadata beforehand).
const fs = require('fs');
const seektable = require('flac-seektable');
const substream = require('flac-substream');
const FLAC_IN = 'input.flac';
const FLAC_OUT = 'output.flac';
const START_SECONDS = 10;
const END_SECONDS = 20;
var reader = fs.createReadStream(FLAC_IN);
reader.pipe(new seektable(function(data) {
var output = fs.createWriteStream(FLAC_OUT, { flags: 'w' });
substream(output, data, START_SECONDS, END_SECONDS, function(start, end) {
var stream = fs.createReadStream(
FLAC_IN,
{
start: start,
end: end
}
);
return stream;
});
})).pipe(
devnull() // Or this could go to somewhere useful.
);
``