音風景ブログ

目隠しテストによるエンコーダの音質評価などを行うブログです。

FFmpeg AACの音質評価

警告

この内容は2012年の古い結果です。
2021年現時点では、FFmpeg公式推奨の Fraunhofer FDK AAC 外部ライブラリ(-c:a libfdk_aac) を推奨します。

  • 現在のFFmpegでは、-cutoffオプションは付けない方が良いです。
  • vo-aacenc のサポートは廃止されました。
  • libfaac のサポートも廃止されました。使おうとするとUnknown encoder ‘libfaac’と言われるはずです。

概要

FFmpegから直接使えるAACエンコーダー3種の評価。
FFmpeg内蔵AACエンコーダー(-strict experimental)については、-cutoffオプションを使用し、最適な-cutoffの値を探った。

結果

libfaac ≒ FFmpeg内蔵AACエンコーダー(-strict experimental -cutoff 15000) > vo-aacenc

評価

エンコーダ FFmpe FFmpe FFmpe FFmpe FFmpe FFmpe
-acodec aac aac aac aac libvo libfaac
-cutoff 13000 15000 17000 19000 　 　
リリース年 2012 2012 2012 2012 2012 2009
バージョン r42106 r42106 r42106 r42106 v0.1.2 r18607
フォーマット AAC AAC AAC AAC AAC AAC
ビットレート 128k 128k 128k 128k 128k 128k
Tarentella 管楽器 3.0 3.5 3.7 3.9 3.1 4.0
水瀬さんち 男女声 3.3 3.9 3.5 3.8 3.0 3.8
Miles Davis ジャズ 3.0 3.9 3.8 3.6 2.5 3.1
58-ギター 弦楽器 3.2 3.6 3.4 3.5 2.7 3.4
55-Haydn 管楽器 3.2 3.5 3.2 3.0 2.3 4.0
41_30sec 打楽器 2.6 3.0 2.7 2.5 2.7 2.7
finalfantasy 撥弦楽 2.5 3.3 3.0 2.6 3.9 2.9
ATrain ジャズ 3.5 4.0 4.2 4.2 2.7 3.5
BigYellow POPS 2.8 3.4 3.6 3.5 2.9 2.5
FloorEssence テクノ 2.8 2.9 2.9 3.0 2.8 3.6
macabre オケ 2.8 3.3 3.6 3.7 2.7 4.2
mybloodrusts 弦楽器 2.8 2.7 2.7 2.7 2.9 3.3
Quizas ラテン 3.0 3.9 3.5 3.4 2.5 3.7
VelvetRealm テクノ 3.3 3.1 3.0 2.9 3.0 3.9
雨降花 POPS 3.0 3.5 3.4 3.0 2.6 3.6
Trust Gosp 2.9 3.5 3.4 3.2 3.2 4.0
Waiting ロック 3.2 3.0 3.2 2.7 2.9 3.1
Experiencia ラテン 2.7 3.3 3.6 3.4 3.1 2.8
HeartToHeart POPS 2.9 3.2 3.2 2.9 3.4 3.2
Tom's Diner 女声 3.1 3.3 3.3 3.2 3.4 2.8
ReunionBlues ジャズ 3.2 3.6 3.8 3.4 3.1 3.5
French 男女声 3.0 3.1 2.9 2.6 2.8 2.5
undelete POPS 3.2 3.7 3.4 3.4 2.6 4.1
Dimmu Borgir メタル 2.9 2.8 3.1 2.9 2.4 4.3
Run up POPS 3.1 3.3 3.6 3.3 3.9 3.4
↑音源 平均点 3.00 3.37 3.35 3.21 2.92 3.44
実レート 128k 128k 129k 130k 130k 129k
全サイズ(KB) 8786 8817 8846 8951 8935 8879
-acodec aac aac aac aac libvo libfaac
エンコーダ FFmpe FFmpe FFmpe FFmpe FFmpe FFmpe

テストに利用した音源を試聴したい方、ダウンロードしたい方、ログを見たい方はこちらへ。
http://zak.s206.xrea.com/bitratetest/main.htm

方法

銘柄に対する先入観が影響しないように、PSP abc/hr v2.3とRP-HT560を利用して、6個の音声ファイルをランダムに並び替えて、銘柄を伏せた状態で聴いて採点した。1.0=音質劣化が非常に気になる 2.0=気になる 3.0=わずかに気になる 4.0=原音からの音質変化が分かるが、気にならない 5.0=音質変化がわからない、区別できない。4.9点以下の評点をつける場合は、ABXYテストを15回行い、12回以上(これ以上の成績をまぐれで出す確率は約2%)正解して、違いを聞き取れることを確認してからそうした。
このテストでの採点は、25(音源)×6(エンコーダ)×1(回)=150(回)。

使用したオプション

 -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 13000
 -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 15000
 -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 17000
 -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 19000
 -acodec libvo_aacenc -ab 128k
 -acodec libfaac -ab 128k

使用したオプション(フル)

echo ===================FFmpeg Native AAC Encoder Section Start===================
bin\ffmpeg42106 -y -i %InputWavFile% -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 13000 "%OutputFile%%Aac1Name%"
bin\ffmpeg42106 -y -i %InputWavFile% -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 15000 "%OutputFile%%Aac2Name%"
bin\ffmpeg42106 -y -i %InputWavFile% -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 17000 "%OutputFile%%Aac3Name%"
bin\ffmpeg42106 -y -i %InputWavFile% -aprofile aac_low -acodec aac -strict experimental -ab 128k -cutoff 19000 "%OutputFile%%Aac4Name%"
bin\faad -b 4 -o %Aac1Decode% "%OutputFile%%Aac1Name%"
bin\faad -b 4 -o %Aac2Decode% "%OutputFile%%Aac2Name%"
bin\faad -b 4 -o %Aac3Decode% "%OutputFile%%Aac3Name%"
bin\faad -b 4 -o %Aac4Decode% "%OutputFile%%Aac4Name%"

echo ===================FFmpeg OpenAMR VisualOn VO-AACENC Section Start===================
bin\ffmpeg42106 -y -i %InputWavFile% -acodec libvo_aacenc -ab 128k "%OutputFile%%Aac5Name%"
bin\faad -b 4 -o %Aac5Decode% "%OutputFile%%Aac5Name%"

echo ===================FFmpeg FAAC (libfaac) Section Start===================
bin\ffmpeg18607 -y -i %InputWavFile% -acodec libfaac -ab 128k "%OutputFile%%Aac6Name%"
bin\faad -b 4 -o %Aac6Decode% "%OutputFile%%Aac6Name%"

詳細な優劣の分析

FRIEDMAN version 1.24 (Jan 17, 2002) http://ff123.net/
Blocked ANOVA analysis

Number of listeners: 25
Critical significance:  0.05
Significance of data: 3.12E-007 (highly significant)
---------------------------------------------------------------
ANOVA Table for Randomized Block Designs Using Ratings

Source of         Degrees     Sum of    Mean
variation         of Freedom  squares   Square    F      p

Total              149          28.67
Testers (blocks)    24           8.20
Codecs eval'd        5           5.55    1.11    8.93  3.12E-007
Error              120          14.93    0.12
---------------------------------------------------------------
Fisher's protected LSD for ANOVA:   0.198

Means:

lib_faac ffexp15k ffexp17k ffexp19k ffexp13k voaacenc
  3.44     3.37     3.35     3.21     3.00     2.92

---------------------------- p-value Matrix ---------------------------

         ffexp15k ffexp17k ffexp19k ffexp13k voaacenc
lib_faac 0.522    0.379    0.027*   0.000*   0.000*
ffexp15k          0.810    0.111    0.000*   0.000*
ffexp17k                   0.175    0.001*   0.000*
ffexp19k                            0.036*   0.005*
ffexp13k                                     0.448
-----------------------------------------------------------------------

lib_faac is better than ffexp19k, ffexp13k, voaacenc
ffexp15k is better than ffexp13k, voaacenc
ffexp17k is better than ffexp13k, voaacenc
ffexp19k is better than ffexp13k, voaacenc

整形済みデータ

% FFmpeg AAC 128kbps ABC/HR score
ffcut13k	ffcut15k	ffcut17k	ffcut19k	voaacenc	lib_faac	
%feature	7	Native experimental	Native experimental	Native experimental	Native experimental	vo-aacenc	libfaac
3.000	3.500	3.700	3.900	3.100	4.000	
3.300	3.900	3.500	3.800	3.000	3.800	
3.000	3.900	3.800	3.600	2.500	3.100	
3.200	3.600	3.400	3.500	2.700	3.400	
3.200	3.500	3.200	3.000	2.300	4.000	
2.600	3.000	2.700	2.500	2.700	2.700	
2.500	3.300	3.000	2.600	3.900	2.900	
3.500	4.000	4.200	4.200	2.700	3.500	
2.800	3.400	3.600	3.500	2.900	2.500	
2.800	2.900	2.900	3.000	2.800	3.600	
2.800	3.300	3.600	3.700	2.700	4.200	
2.800	2.700	2.700	2.700	2.900	3.300	
3.000	3.900	3.500	3.400	2.500	3.700	
3.300	3.100	3.000	2.900	3.000	3.900	
3.000	3.500	3.400	3.000	2.600	3.600	
2.900	3.500	3.400	3.200	3.200	4.000	
3.200	3.000	3.200	2.700	2.900	3.100	
2.700	3.300	3.600	3.400	3.100	2.800	
2.900	3.200	3.200	2.900	3.400	3.200	
3.100	3.300	3.300	3.200	3.400	2.800	
3.200	3.600	3.800	3.400	3.100	3.500	
3.000	3.100	2.900	2.600	2.800	2.500	
3.200	3.700	3.400	3.400	2.600	4.100	
2.900	2.800	3.100	2.900	2.400	4.300	
3.100	3.300	3.600	3.300	3.900	3.400

エンコード・デコードのログ

===================Processing Wav File "D:\autoencode3\05ta_.wav"===================
===================FFmpeg Native AAC Encoder Section Start===================
ffmpeg version N-42106-g5eb353e Copyright (c) 2000-2012 the FFmpeg developers
  built on Jul  2 2012 08:42:45 with gcc 4.7.1
  configuration: --enable-gpl --enable-version3 --enable-avisynth --enable-fontconfig --enable-libass --enable-libbluray --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libcdio --enable
  libavutil      51. 63.100 / 51. 63.100
  libavcodec     54. 31.100 / 54. 31.100
  libavformat    54. 14.100 / 54. 14.100
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     3.  0.100 /  3.  0.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, wav, from 'D:\autoencode3\05ta_.wav':
  Duration: 00:00:04.00, bitrate: 1411 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, stereo, s16, 1411 kb/s
[graph 0 input from stream 0:0 @ 01FFF060] tb:1/44100 samplefmt:s16 samplerate:44100 chlayout:0x3
[auto-inserted resampler 0 @ 01FFFF20] chl:stereo fmt:s16 r:44100Hz -> chl:stereo fmt:flt r:44100Hz
Output #0, mp4, to 'sound_out\05ta_.ffmpeg42106.native-cut13kHz.mp4':
  Metadata:
    encoder         : Lavf54.14.100
    Stream #0:0: Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, flt, 128 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> aac)
Press [q] to stop, [?] for help
size=      68kB time=4.02 bitrate= 137.8kbits/s    
video:0kB audio:66kB subtitle:0 global headers:0kB muxing overhead 2.130894%
ffmpeg version N-42106-g5eb353e Copyright (c) 2000-2012 the FFmpeg developers
  built on Jul  2 2012 08:42:45 with gcc 4.7.1
  configuration: --enable-gpl --enable-version3 --enable-avisynth --enable-fontconfig --enable-libass --enable-libbluray --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libcdio --enable
  libavutil      51. 63.100 / 51. 63.100
  libavcodec     54. 31.100 / 54. 31.100
  libavformat    54. 14.100 / 54. 14.100
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     3.  0.100 /  3.  0.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, wav, from 'D:\autoencode3\05ta_.wav':
  Duration: 00:00:04.00, bitrate: 1411 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, stereo, s16, 1411 kb/s
[graph 0 input from stream 0:0 @ 01E8F060] tb:1/44100 samplefmt:s16 samplerate:44100 chlayout:0x3
[auto-inserted resampler 0 @ 01E8FF20] chl:stereo fmt:s16 r:44100Hz -> chl:stereo fmt:flt r:44100Hz
Output #0, mp4, to 'sound_out\05ta_.ffmpeg42106.native-cut15kHz.mp4':
  Metadata:
    encoder         : Lavf54.14.100
    Stream #0:0: Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, flt, 128 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> aac)
Press [q] to stop, [?] for help
size=      68kB time=4.02 bitrate= 138.0kbits/s    
video:0kB audio:66kB subtitle:0 global headers:0kB muxing overhead 2.128475%
ffmpeg version N-42106-g5eb353e Copyright (c) 2000-2012 the FFmpeg developers
  built on Jul  2 2012 08:42:45 with gcc 4.7.1
  configuration: --enable-gpl --enable-version3 --enable-avisynth --enable-fontconfig --enable-libass --enable-libbluray --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libcdio --enable
  libavutil      51. 63.100 / 51. 63.100
  libavcodec     54. 31.100 / 54. 31.100
  libavformat    54. 14.100 / 54. 14.100
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     3.  0.100 /  3.  0.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, wav, from 'D:\autoencode3\05ta_.wav':
  Duration: 00:00:04.00, bitrate: 1411 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, stereo, s16, 1411 kb/s
[graph 0 input from stream 0:0 @ 0225F060] tb:1/44100 samplefmt:s16 samplerate:44100 chlayout:0x3
[auto-inserted resampler 0 @ 0225FF20] chl:stereo fmt:s16 r:44100Hz -> chl:stereo fmt:flt r:44100Hz
Output #0, mp4, to 'sound_out\05ta_.ffmpeg42106.native-cut17kHz.mp4':
  Metadata:
    encoder         : Lavf54.14.100
    Stream #0:0: Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, flt, 128 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> aac)
Press [q] to stop, [?] for help
size=      67kB time=4.02 bitrate= 137.3kbits/s    
video:0kB audio:66kB subtitle:0 global headers:0kB muxing overhead 2.139291%
ffmpeg version N-42106-g5eb353e Copyright (c) 2000-2012 the FFmpeg developers
  built on Jul  2 2012 08:42:45 with gcc 4.7.1
  configuration: --enable-gpl --enable-version3 --enable-avisynth --enable-fontconfig --enable-libass --enable-libbluray --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libcdio --enable
  libavutil      51. 63.100 / 51. 63.100
  libavcodec     54. 31.100 / 54. 31.100
  libavformat    54. 14.100 / 54. 14.100
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     3.  0.100 /  3.  0.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, wav, from 'D:\autoencode3\05ta_.wav':
  Duration: 00:00:04.00, bitrate: 1411 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, stereo, s16, 1411 kb/s
[graph 0 input from stream 0:0 @ 01E3F060] tb:1/44100 samplefmt:s16 samplerate:44100 chlayout:0x3
[auto-inserted resampler 0 @ 01E3FF20] chl:stereo fmt:s16 r:44100Hz -> chl:stereo fmt:flt r:44100Hz
Output #0, mp4, to 'sound_out\05ta_.ffmpeg42106.native-cut19kHz.mp4':
  Metadata:
    encoder         : Lavf54.14.100
    Stream #0:0: Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, flt, 128 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> aac)
Press [q] to stop, [?] for help
size=      68kB time=4.02 bitrate= 139.0kbits/s    
video:0kB audio:67kB subtitle:0 global headers:0kB muxing overhead 2.112965%
 *********** Ahead Software MPEG-4 AAC Decoder V2.7 ******************

 Build: Jun 14 2010
 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

sound_out\05ta_.ffmpeg42106.native-cut13kHz.mp4 file info:

LC AAC	4.036 secs, 2 ch, 44100 Hz

tool: Lavf54.14.100

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Left front     |
 | 01 | Right front    |
  ---------------------

Decoding sound_out\05ta_.ffmpeg42106.native-cut13kHz.mp4 took:  0.06 sec. 65.10x real-time.
 *********** Ahead Software MPEG-4 AAC Decoder V2.7 ******************

 Build: Jun 14 2010
 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

sound_out\05ta_.ffmpeg42106.native-cut15kHz.mp4 file info:

LC AAC	4.036 secs, 2 ch, 44100 Hz

tool: Lavf54.14.100

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Left front     |
 | 01 | Right front    |
  ---------------------

Decoding sound_out\05ta_.ffmpeg42106.native-cut15kHz.mp4 took:  0.05 sec. 85.88x real-time.
 *********** Ahead Software MPEG-4 AAC Decoder V2.7 ******************

 Build: Jun 14 2010
 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

sound_out\05ta_.ffmpeg42106.native-cut17kHz.mp4 file info:

LC AAC	4.036 secs, 2 ch, 44100 Hz

tool: Lavf54.14.100

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Left front     |
 | 01 | Right front    |
  ---------------------

Decoding sound_out\05ta_.ffmpeg42106.native-cut17kHz.mp4 took:  0.06 sec. 64.07x real-time.
 *********** Ahead Software MPEG-4 AAC Decoder V2.7 ******************

 Build: Jun 14 2010
 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

sound_out\05ta_.ffmpeg42106.native-cut19kHz.mp4 file info:

LC AAC	4.036 secs, 2 ch, 44100 Hz

tool: Lavf54.14.100

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Left front     |
 | 01 | Right front    |
  ---------------------

Decoding sound_out\05ta_.ffmpeg42106.native-cut19kHz.mp4 took:  0.05 sec. 85.88x real-time.
===================FFmpeg OpenAMR VisualOn VO-AACENC Section Start===================
ffmpeg version N-42106-g5eb353e Copyright (c) 2000-2012 the FFmpeg developers
  built on Jul  2 2012 08:42:45 with gcc 4.7.1
  configuration: --enable-gpl --enable-version3 --enable-avisynth --enable-fontconfig --enable-libass --enable-libbluray --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libcdio --enable
  libavutil      51. 63.100 / 51. 63.100
  libavcodec     54. 31.100 / 54. 31.100
  libavformat    54. 14.100 / 54. 14.100
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     3.  0.100 /  3.  0.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, wav, from 'D:\autoencode3\05ta_.wav':
  Duration: 00:00:04.00, bitrate: 1411 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, stereo, s16, 1411 kb/s
[graph 0 input from stream 0:0 @ 03E47960] tb:1/44100 samplefmt:s16 samplerate:44100 chlayout:0x3
Output #0, mp4, to 'sound_out\05ta_.ffmpeg42106.voaacenc.mp4':
  Metadata:
    encoder         : Lavf54.14.100
    Stream #0:0: Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, s16, 128 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> libvo_aacenc)
Press [q] to stop, [?] for help
size=      65kB time=4.00 bitrate= 132.0kbits/s    
video:0kB audio:63kB subtitle:0 global headers:0kB muxing overhead 2.233704%
 *********** Ahead Software MPEG-4 AAC Decoder V2.7 ******************

 Build: Jun 14 2010
 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

sound_out\05ta_.ffmpeg42106.voaacenc.mp4 file info:

LC AAC	4.036 secs, 2 ch, 44100 Hz

tool: Lavf54.14.100

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Left front     |
 | 01 | Right front    |
  ---------------------

Decoding sound_out\05ta_.ffmpeg42106.voaacenc.mp4 took:  0.05 sec. 85.88x real-time.
===================FFmpeg FAAC (libfaac) Section Start===================
FFmpeg version SVN-r18607, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration: --enable-memalign-hack --enable-postproc --enable-gpl --enable-libfaac --enable-libfaad --disable-decoder=aac --enable-libgsm --enable-libmp3lame --enable-libnut --enable-libvorbis --
  libavutil     50. 3. 0 / 50. 3. 0
  libavcodec    52.26. 0 / 52.26. 0
  libavformat   52.32. 0 / 52.32. 0
  libavdevice   52. 2. 0 / 52. 2. 0
  libswscale     0. 7. 1 /  0. 7. 1
  libpostproc   51. 2. 0 / 51. 2. 0
  built on Apr 19 2009 01:58:03, gcc: 4.3.3
Input #0, wav, from 'D:\autoencode3\05ta_.wav':
  Duration: 00:00:04.00, bitrate: 1411 kb/s
    Stream #0.0: Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
Output #0, mp4, to 'sound_out\05ta_.ffmpeg18607.libfaac.mp4':
    Stream #0.0: Audio: libfaac, 44100 Hz, stereo, s16, 128 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
Press [q] to stop encoding
size=      63kB time=3.92 bitrate= 130.9kbits/s    
video:0kB audio:61kB global headers:0kB muxing overhead 3.280245%
 *********** Ahead Software MPEG-4 AAC Decoder V2.7 ******************

 Build: Jun 14 2010
 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

sound_out\05ta_.ffmpeg18607.libfaac.mp4 file info:

LC AAC	3.920 secs, 2 ch, 44100 Hz

tool: Lavf52.32.0

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Left front     |
 | 01 | Right front    |
  ---------------------

Decoding sound_out\05ta_.ffmpeg18607.libfaac.mp4 took:  0.05 sec. 83.41x real-time.
===================Rawgene2 Section Start===================
rawgene v.2.0.0  /  original reference file:sound_raw\05ta_.original.f32b.wav
                     Offset[sample]  Gain    Gain[dB]     Score
FLO 1>05ta_.ffmpeg42> O:    1   G: 1.013651  G: 0.117766  S: 0.083047
FLO 2>05ta_.ffmpeg42> O:    1   G: 1.013456  G: 0.116101  S: 0.144413
FLO 3>05ta_.ffmpeg42> O:    1   G: 1.013334  G: 0.115051  S: 0.233785
FLO 4>05ta_.ffmpeg42> O:    0   G: 1.011589  G: 0.100079  S: 0.162577
FLO 5>05ta_.ffmpeg42> O:  576   G: 1.007004  G: 0.060625  S: 0.117663
FLO 6>05ta_.ffmpeg18> O:    0   G: 0.988632  G:-0.099309  S: 0.154896
biggest_delay    : 576
smallest_delay   : 0
biggest_gain     : 1.013651
shortest_sample  : 171456
initial_offset   : 4100

注：公開試聴試験での多人数の平均評点と管理人の評点が似たような傾向になることは確認しているので言えるが、ある個人がある再生環境で、ある価値観のもとに聞いたときの評価が、ここに書いた管理人の評価に似るかどうかまでは何とも言えない。また、今回利用した音源とは傾向の異なる音を多くエンコードした場合、結果や順位が異なる可能性があります。