我正在使用以下命令将有声读物从 AAX 转换为 M4B：
ffmpeg -activation_bytes xxxxxxxx -i BOOK.AAX -c copy book.m4b
此命令适用于大多数书籍，但超过约 750 MB 的大文件在 iTunes 和 iPod 中的持续时间不正确。我尝试过的 Musicbee 和其他程序都可以正常工作。无法浏览文件，但章节标记可以正常工作。
命令输出：
c:\Utilities\ffmpeg-20200921\bin>ffmpeg -activation_bytes xxxxxxxx -i "E:\test.AAX" -c copy "E:\test.m4b"
ffmpeg version N-99335-gdfbea7b210 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 9.3-win32 (GCC) 20200320
configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 --enable-gpl --enable-version3 --enable-iconv --enable-zlib --enable-libxml2 --enable-libfreetype --enable-libfribidi --enable-gmp --enable-lzma --enable-fontconfig --enable-libvmaf --disable-vulkan --enable-libvorbis --enable-amf --enable-libaom --enable-avisynth --enable-libdav1d --enable-ffnvcodec --enable-cuda-llvm --disable-libglslang --enable-libass --enable-libbluray --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvpx --enable-libwebp --enable-libmfx --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librav1e --enable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libsvtav1 --enable-libtwolame --enable-libvidstab --disable-libwavpack --enable-libx264 --enable-libx265 --enable-libxvid --enable-libzimg --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-libs=-lgomp
libavutil 56. 59.100 / 56. 59.100
libavcodec 58.106.100 / 58.106.100
libavformat 58. 58.100 / 58. 58.100
libavdevice 58. 11.102 / 58. 11.102
libavfilter 7. 87.100 / 7. 87.100
libswscale 5. 8.100 / 5. 8.100
libswresample 3. 8.100 / 3. 8.100
libpostproc 55. 8.100 / 55. 8.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000025962c54e00] [aax] file checksum ==
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000025962c54e00] stream 0, timescale not set
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'E:\test.AAX':
Metadata:
major_brand : aax
minor_version : 1
compatible_brands: aax M4B mp42isom
creation_time : 2020-09-08T15:53:16.000000Z
comment : Chapter 93
title : The Name of the Wind: Kingkiller Chronicle, Book 1
artist : Patrick Rothfuss
album_artist : Patrick Rothfuss
album : The Name of the Wind: Kingkiller Chronicle, Book 1
genre : Audiobook
copyright : ©2009 DAW Trade (P)2009 Brilliance Audio, Inc.
date : 2009
Duration: 27:55:57.74, start: 0.000000, bitrate: 64 kb/s
Chapter #0:0: start 0.000000, end 190.728707
Metadata:
title : Chapter 1
Chapter #0:1: start 190.728707, end 2725.233197
Metadata:
title : Chapter 2
Chapter #0:2: start 2725.233197, end 3225.391020
Metadata:
title : Chapter 3
Chapter #0:3: start 3225.391020, end 5021.593832
Metadata:
title : Chapter 4
Chapter #0:4: start 5021.593832, end 5751.768526
Metadata:
title : Chapter 5
Chapter #0:5: start 5751.768526, end 6188.953832
Metadata:
title : Chapter 6
Chapter #0:6: start 6188.953832, end 7423.140862
Metadata:
title : Chapter 7
Chapter #0:7: start 7423.140862, end 8230.312925
Metadata:
title : Chapter 8
Chapter #0:8: start 8230.312925, end 9876.468390
Metadata:
title : Chapter 9
Chapter #0:9: start 9876.468390, end 10645.652608
Metadata:
title : Chapter 10
Chapter #0:10: start 10645.652608, end 11047.822222
Metadata:
title : Chapter 11
Chapter #0:11: start 11047.822222, end 12023.989116
Metadata:
title : Chapter 12
Chapter #0:12: start 12023.989116, end 13666.150748
Metadata:
title : Chapter 13
Chapter #0:13: start 13666.150748, end 14568.338866
Metadata:
title : Chapter 14
Chapter #0:14: start 14568.338866, end 16003.517823
Metadata:
title : Chapter 15
Chapter #0:15: start 16003.517823, end 16770.705125
Metadata:
title : Chapter 16
Chapter #0:16: start 16770.705125, end 18187.865397
Metadata:
title : Chapter 17
Chapter #0:17: start 18187.865397, end 18494.043719
Metadata:
title : Chapter 18
Chapter #0:18: start 18494.043719, end 19109.233197
Metadata:
title : Chapter 19
Chapter #0:19: start 19109.233197, end 19729.438186
Metadata:
title : Chapter 20
Chapter #0:20: start 19729.438186, end 20937.618866
Metadata:
title : Chapter 21
Chapter #0:21: start 20937.618866, end 21563.814603
Metadata:
title : Chapter 22
Chapter #0:22: start 21563.814603, end 23176.997732
Metadata:
title : Chapter 23
Chapter #0:23: start 23176.997732, end 25249.192925
Metadata:
title : Chapter 24
Chapter #0:24: start 25249.192925, end 25489.380136
Metadata:
title : Chapter 25
Chapter #0:25: start 25489.380136, end 25784.552200
Metadata:
title : Chapter 26
Chapter #0:26: start 25784.552200, end 28231.749660
Metadata:
title : Chapter 27
Chapter #0:27: start 28231.749660, end 28624.909932
Metadata:
title : Chapter 28
Chapter #0:28: start 28624.909932, end 29539.079546
Metadata:
title : Chapter 29
Chapter #0:29: start 29539.079546, end 29846.279546
Metadata:
title : Chapter 30
Chapter #0:30: start 29846.279546, end 30200.476735
Metadata:
title : Chapter 31
Chapter #0:31: start 30200.476735, end 31098.671020
Metadata:
title : Chapter 32
Chapter #0:32: start 31098.671020, end 32217.826395
Metadata:
title : Chapter 33
Chapter #0:33: start 32217.826395, end 32899.006984
Metadata:
title : Chapter 34
Chapter #0:34: start 32899.006984, end 33457.168254
Metadata:
title : Chapter 35
Chapter #0:35: start 33457.168254, end 33851.350204
Metadata:
title : Chapter 36
Chapter #0:36: start 33851.350204, end 35979.551927
Metadata:
title : Chapter 37
Chapter #0:37: start 35979.551927, end 37586.697868
Metadata:
title : Chapter 38
Chapter #0:38: start 37586.697868, end 38888.872925
Metadata:
title : Chapter 39
Chapter #0:39: start 38888.872925, end 39644.078730
Metadata:
title : Chapter 40
Chapter #0:40: start 39644.078730, end 41362.262494
Metadata:
title : Chapter 41
Chapter #0:41: start 41362.262494, end 42204.450249
Metadata:
title : Chapter 42
Chapter #0:42: start 42204.450249, end 43088.619683
Metadata:
title : Chapter 43
Chapter #0:43: start 43088.619683, end 45214.778050
Metadata:
title : Chapter 44
Chapter #0:44: start 45214.778050, end 46355.945941
Metadata:
title : Chapter 45
Chapter #0:45: start 46355.945941, end 46616.148753
Metadata:
title : Chapter 46
Chapter #0:46: start 46616.148753, end 48366.329615
Metadata:
title : Chapter 47
Chapter #0:47: start 48366.329615, end 48727.492789
Metadata:
title : Chapter 48
Chapter #0:48: start 48727.492789, end 49112.665397
Metadata:
title : Chapter 49
Chapter #0:49: start 49112.665397, end 49490.872018
Metadata:
title : Chapter 50
Chapter #0:50: start 49490.872018, end 50915.044717
Metadata:
title : Chapter 51
Chapter #0:51: start 50915.044717, end 51550.203356
Metadata:
title : Chapter 52
Chapter #0:52: start 51550.203356, end 53249.393197
Metadata:
title : Chapter 53
Chapter #0:53: start 53249.393197, end 54093.577868
Metadata:
title : Chapter 54
Chapter #0:54: start 54093.577868, end 56342.755556
Metadata:
title : Chapter 55
Chapter #0:55: start 56342.755556, end 56432.941859
Metadata:
title : Chapter 56
Chapter #0:56: start 56432.941859, end 57963.136871
Metadata:
title : Chapter 57
Chapter #0:57: start 57963.136871, end 58539.316825
Metadata:
title : Chapter 58
Chapter #0:58: start 58539.316825, end 59977.514376
Metadata:
title : Chapter 59
Chapter #0:59: start 59977.514376, end 60076.663583
Metadata:
title : Chapter 60
Chapter #0:60: start 60076.663583, end 61934.863673
Metadata:
title : Chapter 61
Chapter #0:61: start 61934.863673, end 63462.040091
Metadata:
title : Chapter 62
Chapter #0:62: start 63462.040091, end 64937.203810
Metadata:
title : Chapter 63
Chapter #0:63: start 64937.203810, end 65434.389478
Metadata:
title : Chapter 64
Chapter #0:64: start 65434.389478, end 66356.593197
Metadata:
title : Chapter 65
Chapter #0:65: start 66356.593197, end 67552.792381
Metadata:
title : Chapter 66
Chapter #0:66: start 67552.792381, end 68699.951020
Metadata:
title : Chapter 67
Chapter #0:67: start 68699.951020, end 69503.129252
Metadata:
title : Chapter 68
Chapter #0:68: start 69503.129252, end 71055.290340
Metadata:
title : Chapter 69
Chapter #0:69: start 71055.290340, end 73339.483719
Metadata:
title : Chapter 70
Chapter #0:70: start 73339.483719, end 74739.646984
Metadata:
title : Chapter 71
Chapter #0:71: start 74739.646984, end 76989.799909
Metadata:
title : Chapter 72
Chapter #0:72: start 76989.799909, end 79985.081179
Metadata:
title : Chapter 73
Chapter #0:73: start 79985.081179, end 81746.268299
Metadata:
title : Chapter 74
Chapter #0:74: start 81746.268299, end 82711.428934
Metadata:
title : Chapter 75
Chapter #0:75: start 82711.428934, end 82815.593651
Metadata:
title : Chapter 76
Chapter #0:76: start 82815.593651, end 83242.794376
Metadata:
title : Chapter 77
Chapter #0:77: start 83242.794376, end 85966.030658
Metadata:
title : Chapter 78
Chapter #0:78: start 85966.030658, end 86589.207800
Metadata:
title : Chapter 79
Chapter #0:79: start 86589.207800, end 87930.392381
Metadata:
title : Chapter 80
Chapter #0:80: start 87930.392381, end 89250.586122
Metadata:
title : Chapter 81
Chapter #0:81: start 89250.586122, end 89325.772336
Metadata:
title : Chapter 82
Chapter #0:82: start 89325.772336, end 90794.945306
Metadata:
title : Chapter 83
Chapter #0:83: start 90794.945306, end 91014.141678
Metadata:
title : Chapter 84
Chapter #0:84: start 91014.141678, end 92237.322449
Metadata:
title : Chapter 85
Chapter #0:85: start 92237.322449, end 92911.490612
Metadata:
title : Chapter 86
Chapter #0:86: start 92911.490612, end 93676.680998
Metadata:
title : Chapter 87
Chapter #0:87: start 93676.680998, end 94375.880272
Metadata:
title : Chapter 88
Chapter #0:88: start 94375.880272, end 97204.117188
Metadata:
title : Chapter 89
Chapter #0:89: start 97204.117188, end 97281.300317
Metadata:
title : Chapter 90
Chapter #0:90: start 97281.300317, end 98427.483719
Metadata:
title : Chapter 91
Chapter #0:91: start 98427.483719, end 98986.666667
Metadata:
title : Chapter 92
Chapter #0:92: start 98986.666667, end 100557.740000
Metadata:
title : Chapter 93
Stream #0:0(eng): Audio: aac (LC) (aavd / 0x64766161), 22050 Hz, stereo, fltp, 62 kb/s (default)
Metadata:
creation_time : 2020-09-08T15:53:16.000000Z
handler_name : ?Apple Sound Media Handler
Stream #0:1(eng): Data: bin_data (text / 0x74786574) (default)
Metadata:
creation_time : 2020-09-08T15:53:18.000000Z
handler_name : ?Apple Text Media Handler
Stream #0:2: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 500x500 [SAR 1:1 DAR 1:1], 90k tbr, 90k tbn, 90k tbc (attached pic)
Output #0, ipod, to 'E:\test.m4b':
Metadata:
major_brand : aax
minor_version : 1
compatible_brands: aax M4B mp42isom
date : 2009
comment : Chapter 93
title : The Name of the Wind: Kingkiller Chronicle, Book 1
artist : Patrick Rothfuss
album_artist : Patrick Rothfuss
album : The Name of the Wind: Kingkiller Chronicle, Book 1
genre : Audiobook
copyright : ©2009 DAW Trade (P)2009 Brilliance Audio, Inc.
encoder : Lavf58.58.100
Chapter #0:0: start 0.000000, end 190.728707
Metadata:
title : Chapter 1
Chapter #0:1: start 190.728707, end 2725.233197
Metadata:
title : Chapter 2
Chapter #0:2: start 2725.233197, end 3225.391020
Metadata:
title : Chapter 3
Chapter #0:3: start 3225.391020, end 5021.593832
Metadata:
title : Chapter 4
Chapter #0:4: start 5021.593832, end 5751.768526
Metadata:
title : Chapter 5
Chapter #0:5: start 5751.768526, end 6188.953832
Metadata:
title : Chapter 6
Chapter #0:6: start 6188.953832, end 7423.140862
Metadata:
title : Chapter 7
Chapter #0:7: start 7423.140862, end 8230.312925
Metadata:
title : Chapter 8
Chapter #0:8: start 8230.312925, end 9876.468390
Metadata:
title : Chapter 9
Chapter #0:9: start 9876.468390, end 10645.652608
Metadata:
title : Chapter 10
Chapter #0:10: start 10645.652608, end 11047.822222
Metadata:
title : Chapter 11
Chapter #0:11: start 11047.822222, end 12023.989116
Metadata:
title : Chapter 12
Chapter #0:12: start 12023.989116, end 13666.150748
Metadata:
title : Chapter 13
Chapter #0:13: start 13666.150748, end 14568.338866
Metadata:
title : Chapter 14
Chapter #0:14: start 14568.338866, end 16003.517823
Metadata:
title : Chapter 15
Chapter #0:15: start 16003.517823, end 16770.705125
Metadata:
title : Chapter 16
Chapter #0:16: start 16770.705125, end 18187.865397
Metadata:
title : Chapter 17
Chapter #0:17: start 18187.865397, end 18494.043719
Metadata:
title : Chapter 18
Chapter #0:18: start 18494.043719, end 19109.233197
Metadata:
title : Chapter 19
Chapter #0:19: start 19109.233197, end 19729.438186
Metadata:
title : Chapter 20
Chapter #0:20: start 19729.438186, end 20937.618866
Metadata:
title : Chapter 21
Chapter #0:21: start 20937.618866, end 21563.814603
Metadata:
title : Chapter 22
Chapter #0:22: start 21563.814603, end 23176.997732
Metadata:
title : Chapter 23
Chapter #0:23: start 23176.997732, end 25249.192925
Metadata:
title : Chapter 24
Chapter #0:24: start 25249.192925, end 25489.380136
Metadata:
title : Chapter 25
Chapter #0:25: start 25489.380136, end 25784.552200
Metadata:
title : Chapter 26
Chapter #0:26: start 25784.552200, end 28231.749660
Metadata:
title : Chapter 27
Chapter #0:27: start 28231.749660, end 28624.909932
Metadata:
title : Chapter 28
Chapter #0:28: start 28624.909932, end 29539.079546
Metadata:
title : Chapter 29
Chapter #0:29: start 29539.079546, end 29846.279546
Metadata:
title : Chapter 30
Chapter #0:30: start 29846.279546, end 30200.476735
Metadata:
title : Chapter 31
Chapter #0:31: start 30200.476735, end 31098.671020
Metadata:
title : Chapter 32
Chapter #0:32: start 31098.671020, end 32217.826395
Metadata:
title : Chapter 33
Chapter #0:33: start 32217.826395, end 32899.006984
Metadata:
title : Chapter 34
Chapter #0:34: start 32899.006984, end 33457.168254
Metadata:
title : Chapter 35
Chapter #0:35: start 33457.168254, end 33851.350204
Metadata:
title : Chapter 36
Chapter #0:36: start 33851.350204, end 35979.551927
Metadata:
title : Chapter 37
Chapter #0:37: start 35979.551927, end 37586.697868
Metadata:
title : Chapter 38
Chapter #0:38: start 37586.697868, end 38888.872925
Metadata:
title : Chapter 39
Chapter #0:39: start 38888.872925, end 39644.078730
Metadata:
title : Chapter 40
Chapter #0:40: start 39644.078730, end 41362.262494
Metadata:
title : Chapter 41
Chapter #0:41: start 41362.262494, end 42204.450249
Metadata:
title : Chapter 42
Chapter #0:42: start 42204.450249, end 43088.619683
Metadata:
title : Chapter 43
Chapter #0:43: start 43088.619683, end 45214.778050
Metadata:
title : Chapter 44
Chapter #0:44: start 45214.778050, end 46355.945941
Metadata:
title : Chapter 45
Chapter #0:45: start 46355.945941, end 46616.148753
Metadata:
title : Chapter 46
Chapter #0:46: start 46616.148753, end 48366.329615
Metadata:
title : Chapter 47
Chapter #0:47: start 48366.329615, end 48727.492789
Metadata:
title : Chapter 48
Chapter #0:48: start 48727.492789, end 49112.665397
Metadata:
title : Chapter 49
Chapter #0:49: start 49112.665397, end 49490.872018
Metadata:
title : Chapter 50
Chapter #0:50: start 49490.872018, end 50915.044717
Metadata:
title : Chapter 51
Chapter #0:51: start 50915.044717, end 51550.203356
Metadata:
title : Chapter 52
Chapter #0:52: start 51550.203356, end 53249.393197
Metadata:
title : Chapter 53
Chapter #0:53: start 53249.393197, end 54093.577868
Metadata:
title : Chapter 54
Chapter #0:54: start 54093.577868, end 56342.755556
Metadata:
title : Chapter 55
Chapter #0:55: start 56342.755556, end 56432.941859
Metadata:
title : Chapter 56
Chapter #0:56: start 56432.941859, end 57963.136871
Metadata:
title : Chapter 57
Chapter #0:57: start 57963.136871, end 58539.316825
Metadata:
title : Chapter 58
Chapter #0:58: start 58539.316825, end 59977.514376
Metadata:
title : Chapter 59
Chapter #0:59: start 59977.514376, end 60076.663583
Metadata:
title : Chapter 60
Chapter #0:60: start 60076.663583, end 61934.863673
Metadata:
title : Chapter 61
Chapter #0:61: start 61934.863673, end 63462.040091
Metadata:
title : Chapter 62
Chapter #0:62: start 63462.040091, end 64937.203810
Metadata:
title : Chapter 63
Chapter #0:63: start 64937.203810, end 65434.389478
Metadata:
title : Chapter 64
Chapter #0:64: start 65434.389478, end 66356.593197
Metadata:
title : Chapter 65
Chapter #0:65: start 66356.593197, end 67552.792381
Metadata:
title : Chapter 66
Chapter #0:66: start 67552.792381, end 68699.951020
Metadata:
title : Chapter 67
Chapter #0:67: start 68699.951020, end 69503.129252
Metadata:
title : Chapter 68
Chapter #0:68: start 69503.129252, end 71055.290340
Metadata:
title : Chapter 69
Chapter #0:69: start 71055.290340, end 73339.483719
Metadata:
title : Chapter 70
Chapter #0:70: start 73339.483719, end 74739.646984
Metadata:
title : Chapter 71
Chapter #0:71: start 74739.646984, end 76989.799909
Metadata:
title : Chapter 72
Chapter #0:72: start 76989.799909, end 79985.081179
Metadata:
title : Chapter 73
Chapter #0:73: start 79985.081179, end 81746.268299
Metadata:
title : Chapter 74
Chapter #0:74: start 81746.268299, end 82711.428934
Metadata:
title : Chapter 75
Chapter #0:75: start 82711.428934, end 82815.593651
Metadata:
title : Chapter 76
Chapter #0:76: start 82815.593651, end 83242.794376
Metadata:
title : Chapter 77
Chapter #0:77: start 83242.794376, end 85966.030658
Metadata:
title : Chapter 78
Chapter #0:78: start 85966.030658, end 86589.207800
Metadata:
title : Chapter 79
Chapter #0:79: start 86589.207800, end 87930.392381
Metadata:
title : Chapter 80
Chapter #0:80: start 87930.392381, end 89250.586122
Metadata:
title : Chapter 81
Chapter #0:81: start 89250.586122, end 89325.772336
Metadata:
title : Chapter 82
Chapter #0:82: start 89325.772336, end 90794.945306
Metadata:
title : Chapter 83
Chapter #0:83: start 90794.945306, end 91014.141678
Metadata:
title : Chapter 84
Chapter #0:84: start 91014.141678, end 92237.322449
Metadata:
title : Chapter 85
Chapter #0:85: start 92237.322449, end 92911.490612
Metadata:
title : Chapter 86
Chapter #0:86: start 92911.490612, end 93676.680998
Metadata:
title : Chapter 87
Chapter #0:87: start 93676.680998, end 94375.880272
Metadata:
title : Chapter 88
Chapter #0:88: start 94375.880272, end 97204.117188
Metadata:
title : Chapter 89
Chapter #0:89: start 97204.117188, end 97281.300317
Metadata:
title : Chapter 90
Chapter #0:90: start 97281.300317, end 98427.483719
Metadata:
title : Chapter 91
Chapter #0:91: start 98427.483719, end 98986.666667
Metadata:
title : Chapter 92
Chapter #0:92: start 98986.666667, end 100557.740000
Metadata:
title : Chapter 93
Stream #0:0: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 500x500 [SAR 1:1 DAR 1:1], q=2-31, 90k tbr, 90k tbn, 90k tbc (attached pic)
Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 22050 Hz, stereo, fltp, 62 kb/s (default)
Metadata:
creation_time : 2020-09-08T15:53:16.000000Z
handler_name : ?Apple Sound Media Handler
Stream mapping:
Stream #0:2 -> #0:0 (copy)
Stream #0:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame= 1 fps=0.0 q=-1.0 Lsize= 779347kB time=27:55:57.72 bitrate= 63.5kbits/s speed=1.21e+03x
video:68kB audio:770806kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.099302%
我知道这在旧版本上可以正常工作（肯定是 3.1.4），但旧版本不会在没有单独程序的情况下复制图稿。请注意，旧版本需要格式标志，我在新版本上尝试过，但没有效果：
ffmpeg -activation_bytes xxxxxxxx -i BOOK.AAX -c copy -f mp4 book.m4b
我以为封面艺术可能是问题所在，于是尝试了 -vn 标志，但没有效果。但是，先转换为 AAC，然后转换为 M4B，会输出一个可用的文件。这些命令输出一个好的文件，没有章节、封面艺术等：
ffmpeg -activation_bytes XXXX -i "book.AAX" -c:a copy "temp.aac"
ffmpeg -i "temp.aac" -c:a copy "book.m4b"
是否有命令参数可以修复这些较大的文件（除了扔掉 iPod）？对我来说这似乎是一个错误，但我犹豫着是否提交，因为我对 ffmpeg 没有什么经验。