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A modern, network-enabled music player platform built on Rockbox technology. rockboxd.tsiry-sandratraina.com
rust deno navidrome airplay libadwaita zig mpris snapcast mpd rockbox audio subsonic
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require "json"
module RockboxFFI # Decode a local audio file to interleaved-stereo S16 PCM, one chunk at a # time, using the Rockbox codec engine. # # The codec state is process-wide, so only one Decoder may decode at a time # and it must be used from one thread. Call #close when done, or use the block # form Decoder.open(path) { |dec| ... }. class Decoder # Open a Decoder for +path+; if a block is given, close it automatically # afterwards. def self.open(path) dec = new(path) return dec unless block_given?
begin yield dec ensure dec.close end end
def initialize(path) @ptr = Lib.rb_decoder_open(path.to_s) raise "could not open decoder for #{path.inspect}" if @ptr.null?
@finalizer = self.class.send(:finalizer, @ptr) ObjectSpace.define_finalizer(self, @finalizer) end
# -- lifecycle -------------------------------------------------------- def close return if @ptr.nil?
ObjectSpace.undefine_finalizer(self) Lib.rb_decoder_free(@ptr) @ptr = nil end
def closed? @ptr.nil? end
def self.finalizer(ptr) proc { Lib.rb_decoder_free(ptr) } end private_class_method :finalizer
# -- metadata --------------------------------------------------------- # Tags and stream properties (same shape as Metadata.read). Returns a Hash # with symbol keys. Raises on failure. def metadata s = RockboxFFI.take_string(Lib.rb_decoder_metadata_json(@ptr)) raise "rb_decoder_metadata_json returned NULL" if s.nil?
JSON.parse(s, symbolize_names: true) end
# -- decoding --------------------------------------------------------- # Next buffer of decoded PCM as +[samples, sample_rate]+, where +samples+ # is an Array of interleaved stereo int16 Integers. Returns nil at end of # track (or after a codec error — see #finished). def next_chunk out_len = "\0" * Fiddle::SIZEOF_VOIDP # size_t* out-param (i16 count) out_rate = "\0" * Fiddle::SIZEOF_INT # uint32_t* out-param (Hz) ptr = Lib.rb_decoder_next_chunk(@ptr, out_len, out_rate)
produced = out_len.unpack1(Fiddle::SIZEOF_VOIDP == 8 ? "Q" : "L") return nil if ptr.null? || produced.zero?
rate = out_rate.unpack1("L") begin ptr.size = produced * 2 [ptr[0, produced * 2].unpack("s<*"), rate] ensure Lib.rb_buffer_free(ptr, produced) end end
# Yield each +[samples, sample_rate]+ chunk until end of track. Returns an # Enumerator when no block is given. def each_chunk return enum_for(:each_chunk) unless block_given?
while (chunk = next_chunk) yield chunk end end
# Request a seek to +ms+ milliseconds. def seek_ms(ms) Lib.rb_decoder_seek_ms(@ptr, Integer(ms)) end
# Playback position last reported by the codec, in milliseconds. def elapsed_ms Lib.rb_decoder_elapsed_ms(@ptr) end
# +[done, code]+: +done+ is true once the track has ended; +code+ is the # exit status (0 = clean end, negative = codec error), valid only when # +done+. def finished out_code = "\0" * Fiddle::SIZEOF_INT # int32_t* out-param r = Lib.rb_decoder_finished(@ptr, out_code) done = r == true || r == 1 [done, out_code.unpack1("l")] end endend