lib/scissor/writer.rb in scissor-0.2.9 vs lib/scissor/writer.rb in scissor-0.3.0

@@ -26,14 +26,17 @@
     end
 
     def join_fragments(fragments, outfile, tmpdir)
       position = 0.0
       cmd = %w/ecasound/
+      is_mono = {}
 
       fragments.each_with_index do |fragment, index|
         fragment_filename = fragment.filename
 
+        is_mono[fragment_filename] ||= mono?(fragment_filename)
+
         if !index.zero? && (index % 28).zero?
           run_command(cmd.join(' '))
           cmd = %w/ecasound/
         end
 
@@ -42,11 +45,11 @@
         unless fragment_outfile.exist?
           movie = FFMPEG::Movie.new(fragment_filename.to_s)
           movie.transcode(fragment_outfile.to_s, :audio_sample_rate => 44100)
         end
 
-        cmd << "-a:#{index} -o:#{outfile} -y:#{position}"
+        cmd << "-a:#{index} -o:#{outfile} -y:#{position}#{is_mono[fragment_filename] ? ' -chcopy:1,2' : ''}"
 
         if fragment.stretched? && fragment.pitch.to_f != 100.0
           rubberband_out = tmpdir + (Digest::MD5.hexdigest(fragment_filename.to_s) + "rubberband_#{index}.wav")
           rubberband_temp = tmpdir + "_rubberband.wav"
 
@@ -144,8 +147,14 @@
       if status && status.exitstatus != 0
         raise CommandFailed.new(cmd)
       end
 
       return result
+    end
+
+    private
+
+    def mono?(filename)
+      SoundFile.new_from_filename(filename).mono?
     end
   end
 end