new file mode 100755
@@ -0,0 +1,61 @@
+#!/usr/bin/env ruby
+
+require 'open3'
+require 'json'
+
+ffmpeg_bin = 'ffmpeg'
+target_il = -24.0
+target_lra = +11.0
+target_tp = -2.0
+samplerate = '48k'
+
+if ARGF.argv.count != 2
+ puts "Usage: #{$PROGRAM_NAME} input.wav output.wav"
+ exit 1
+end
+
+ff_cmd = Array.new([
+ ffmpeg_bin,
+ '-hide_banner',
+ '-i', ARGF.argv[0],
+ '-af', "loudnorm='I=#{target_il}:LRA=#{target_lra}:tp=#{target_tp}:print_format=json'",
+ '-f', 'null',
+ '-']);
+
+_stdin, _stdout, stderr, wait_thr = Open3.popen3(*ff_cmd)
+
+if wait_thr.value.success?
+ stats = JSON.parse(stderr.read.lines[-12, 12].join)
+ loudnorm_string = 'loudnorm='
+ loudnorm_string += 'print_format=summary:'
+ loudnorm_string += 'linear=true:'
+ loudnorm_string += "I=#{target_il}:"
+ loudnorm_string += "LRA=#{target_lra}:"
+ loudnorm_string += "tp=#{target_tp}:"
+ loudnorm_string += "measured_I=#{stats['input_i']}:"
+ loudnorm_string += "measured_LRA=#{stats['input_lra']}:"
+ loudnorm_string += "measured_tp=#{stats['input_tp']}:"
+ loudnorm_string += "measured_thresh=#{stats['input_thresh']}:"
+ loudnorm_string += "offset=#{stats['target_offset']}"
+else
+ puts stderr.read
+ exit 1
+end
+
+ff_cmd = Array.new([
+ ffmpeg_bin,
+ '-y', '-hide_banner',
+ '-i', ARGF.argv[0],
+ '-af', loudnorm_string,
+ '-ar', samplerate,
+ ARGF.argv[1].to_s]);
+
+_stdin, _stdout, stderr, wait_thr = Open3.popen3(*ff_cmd)
+
+if wait_thr.value.success?
+ puts stderr.read.lines[-12, 12].join
+ exit 0
+else
+ puts stderr.read
+ exit 1
+end
Based on a patch by Kyle Swanson <k@ylo.ph>. Signed-off-by: Marton Balint <cus@passwd.hu> --- tools/loudnorm.rb | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100755 tools/loudnorm.rb