Class: NuWav::WaveFile
- Inherits:
-
Object
- Object
- NuWav::WaveFile
- Defined in:
- lib/nu_wav/wave_file.rb
Instance Attribute Summary collapse
-
#chunks ⇒ Object
Returns the value of attribute chunks.
-
#header ⇒ Object
Returns the value of attribute header.
Class Method Summary collapse
- .calculate_mpeg_frame_size(info) ⇒ Object
- .calculate_mpeg_head_flags(info) ⇒ Object
- .calculate_mpeg_samples_number(file, info) ⇒ Object
-
.from_mpeg(file_name) ⇒ Object
method to create a wave file using the.
- .parse(wave_file) ⇒ Object
Instance Method Summary collapse
- #duration ⇒ Object
-
#initialize ⇒ WaveFile
constructor
A new instance of WaveFile.
- #is_mpeg? ⇒ Boolean
- #is_pcm? ⇒ Boolean
- #parse(wave_file) ⇒ Object
- #to_file(file_name, options = {}) ⇒ Object
- #to_s ⇒ Object
- #write_data_file(file_name) ⇒ Object
Constructor Details
#initialize ⇒ WaveFile
Returns a new instance of WaveFile.
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# File 'lib/nu_wav/wave_file.rb', line 11 def initialize self.chunks = {} end |
Instance Attribute Details
#chunks ⇒ Object
Returns the value of attribute chunks.
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# File 'lib/nu_wav/wave_file.rb', line 5 def chunks @chunks end |
#header ⇒ Object
Returns the value of attribute header.
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# File 'lib/nu_wav/wave_file.rb', line 5 def header @header end |
Class Method Details
.calculate_mpeg_frame_size(info) ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 245 def self.calculate_mpeg_frame_size(info) samples_per_frame = Mp3Info::SAMPLES_PER_FRAME[info.layer][info.mpeg_version] ((samples_per_frame / 8) * (info.bitrate * 1000))/info.samplerate end |
.calculate_mpeg_head_flags(info) ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 235 def self.calculate_mpeg_head_flags(info) flags = 0 flags += 1 if (info.header[:private_bit]) flags += 2 if (info.header[:copyright]) flags += 4 if (info.header[:original]) flags += 8 if (info.header[:error_protection]) flags += 16 if (info.mpeg_version > 0) flags end |
.calculate_mpeg_samples_number(file, info) ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 231 def self.calculate_mpeg_samples_number(file, info) (File.size(file.path) / calculate_mpeg_frame_size(info)) * Mp3Info::SAMPLES_PER_FRAME[info.layer][info.mpeg_version] end |
.from_mpeg(file_name) ⇒ Object
method to create a wave file using the
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# File 'lib/nu_wav/wave_file.rb', line 151 def self.from_mpeg(file_name) # read and display infos & tags NuWav::WaveFile.log "NuWav::from_mpeg::file_name:#{file_name}" mp3info = Mp3Info.open(file_name) NuWav::WaveFile.log mp3info file = File.open(file_name) wave = WaveFile.new # data chunk data = DataChunk.new_from_file(file) wave.chunks[:data] = data # fmt chunk fmt = FmtChunk.new fmt.compression_code = MPEG_COMPRESSION fmt.number_of_channels = (mp3info.channel_mode == "Single Channel") ? 1 : 2 fmt.sample_rate = mp3info.samplerate fmt.byte_rate = mp3info.bitrate / 8 * 1000 fmt.block_align = calculate_mpeg_frame_size(mp3info) fmt.sample_bits = 65535 fmt.extra_size = 22 fmt.head_layer = ACM_LAYERS[mp3info.layer.to_i-1] fmt.head_bit_rate = mp3info.bitrate * 1000 fmt.head_mode = CHANNEL_MODES[mp3info.channel_mode] # fmt.head_mode_ext = (mp3info.channel_mode == "JStereo") ? 2**mp3info.mode_extension : 0 fmt.head_mode_ext = (mp3info.channel_mode == "JStereo") ? 2**mp3info.header[:mode_extension] : 0 # fmt.head_emphasis = mp3info.emphasis + 1 fmt.head_emphasis = mp3info.header[:emphasis] + 1 fmt.head_flags = calculate_mpeg_head_flags(mp3info) fmt.pts_low = 0 fmt.pts_high = 0 wave.chunks[:fmt] = fmt # NuWav::WaveFile.log "fmt: #{fmt}" # fact chunk fact = FactChunk.new fact.samples_number = calculate_mpeg_samples_number(file, mp3info) wave.chunks[:fact] = fact # NuWav::WaveFile.log "fact: #{fact}" #mext chunk mext = MextChunk.new mext.sound_information = 5 mext.sound_information += 2 if mp3info.header[:padding] mext.frame_size = calculate_mpeg_frame_size(mp3info) mext.ancillary_data_length = 0 mext.ancillary_data_def = 0 wave.chunks[:mext] = mext # NuWav::WaveFile.log "mext: #{mext}" #bext chunk bext = BextChunk.new bext.time_reference_high = 0 bext.time_reference_low = 0 bext.version = 1 bext.coding_history = "A=MPEG1L#{mp3info.layer},F=#{mp3info.samplerate},B=#{mp3info.bitrate},M=#{CODING_HISTORY_MODE[mp3info.channel_mode]},T=PRX\r\n\0\0" wave.chunks[:bext] = bext # NuWav::WaveFile.log "bext: #{bext}" #cart chunk cart = CartChunk.new now = Time.now today = Date.today later = today << 12 cart.version = '0101' cart.title = File.basename(file_name) # this is just a default cart.start_date = today.strftime("%Y-%m-%d") cart.start_time = now.strftime("%H:%M:%S") cart.end_date = later.strftime("%Y-%m-%d") cart.end_time = now.strftime("%H:%M:%S") cart.producer_app_id = 'NuWav' cart.producer_app_version = '1.0' cart.level_reference = 0 cart.tag_text = "\r\n" wave.chunks[:cart] = cart # NuWav::WaveFile.log "cart: #{cart}" wave end |
Instance Method Details
#duration ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 79 def duration fmt = @chunks[:fmt] if (PCM_COMPRESSION.include?(fmt.compression_code.to_i)) data = @chunks[:data] data.size / (fmt.sample_rate * fmt.number_of_channels * (fmt.sample_bits / 8)) elsif (fmt.compression_code.to_i == MPEG_COMPRESSION) # <chunk type:fact samples_number:78695424 /> fact = @chunks[:fact] fact.samples_number / fmt.sample_rate else raise "Duration implemented for PCM and MEPG files only." end end |
#is_mpeg? ⇒ Boolean
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# File 'lib/nu_wav/wave_file.rb', line 94 def is_mpeg? (@chunks[:fmt] && (@chunks[:fmt].compression_code.to_i == MPEG_COMPRESSION)) end |
#is_pcm? ⇒ Boolean
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# File 'lib/nu_wav/wave_file.rb', line 98 def is_pcm? (@chunks[:fmt] && (PCM_COMPRESSION.include?(@chunks[:fmt].compression_code.to_i))) end |
#parse(wave_file) ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 15 def parse(wave_file) NuWav::WaveFile.log "Processing wave file #{wave_file.inspect}...." wave_file_size = File.size(wave_file) File.open(wave_file, 'r') do |f| #only for windows, make sure we are operating in binary mode f.binmode #start at the very beginning, a very good place to start f.seek(0) riff, riff_length = read_chunk_header(f) NuWav::WaveFile.log "riff: #{riff}" NuWav::WaveFile.log "riff_length: #{riff_length}" NuWav::WaveFile.log "wave_file_size: #{wave_file_size}" raise NotRIFFFormat unless riff == 'RIFF' || riff == 'RF64' riff_end = [f.tell + riff_length, wave_file_size].min riff_type = f.read(4) raise NotWAVEFormat unless riff_type == 'WAVE' @header = RiffChunk.new(riff, riff_length, riff_type) while (f.tell + 8) <= riff_end NuWav::WaveFile.log "while #{f.tell} < #{riff_end}" chunk_name, chunk_length = read_chunk_header(f) fpos = f.tell NuWav::WaveFile.log "found chunk: '#{chunk_name}', size #{chunk_length}" if chunk_name && chunk_length self.chunks[chunk_name.to_sym] = chunk_class(chunk_name).parse(chunk_name, chunk_length, f) parsed_chunk_size = self.chunks[chunk_name.to_sym].size NuWav::WaveFile.log "about to do a seek..." NuWav::WaveFile.log "f.seek #{fpos} + #{parsed_chunk_size}" f.seek(fpos + parsed_chunk_size) NuWav::WaveFile.log "seek done" if parsed_chunk_size.odd? NuWav::WaveFile.log("parsed_chunk_size is ODD #{chunk_name}: #{parsed_chunk_size}") pad = f.read(1) if (pad.nil? || pad.ord != 0) NuWav::WaveFile.log("NOT PADDED") self.chunks[chunk_name.to_sym].pad_byte = false f.seek(fpos + parsed_chunk_size) else self.chunks[chunk_name.to_sym].pad_byte = true end end else NuWav::WaveFile.log "chunk or length was off - remainder of file does not parse properly: #{riff_end} - #{fpos} = #{riff_end - fpos}" f.seek(riff_end) end end end @chunks.each{|k,v| NuWav::WaveFile.log "#{k}: #{v}\n\n" unless k.to_s == 'data'} NuWav::WaveFile.log "parse done" self end |
#to_file(file_name, options = {}) ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 110 def to_file(file_name, ={}) if [:add_extension] && !(file_name =~ /\.wav/) file_name += ".wav" end NuWav::WaveFile.log "NuWav::WaveFile.to_file: file_name = #{file_name}" #get all the chunks together to get final length chunks_out = [:fmt, :fact, :mext, :bext, :cart, :data].inject([]) do |list, chunk| if self.chunks[chunk] out = self.chunks[chunk].to_binary() NuWav::WaveFile.log out.length list << out end list end # TODO: handle other chunks not in the above list, but that might have been in a parsed wav riff_length = chunks_out.inject(0){|sum, chunk| sum += chunk.size} NuWav::WaveFile.log "NuWav::WaveFile.to_file: riff_length = #{riff_length}" #open file for writing open(file_name, "wb") do |o| #write the header o << "RIFF" o << [(riff_length + 4)].pack('V') o << "WAVE" #write the chunks chunks_out.each{|c| o << c} end end |
#to_s ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 102 def to_s out = "NuWav:#{@header}\n" out = [:fmt, :fact, :mext, :bext, :cart, :data ].inject(out) do |s, chunk| s += "#{self.chunks[chunk]}\n" if self.chunks[chunk] s end end |
#write_data_file(file_name) ⇒ Object
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# File 'lib/nu_wav/wave_file.rb', line 143 def write_data_file(file_name) open(file_name, "wb") do |o| o << chunks[:data].data end end |