mp3和wmv的压缩

When I am browsing HSK test files (level 6) here (http://www.chinesetest.cn/godownload.do), I found that the decompressed mp3 and wmv is actually larger than the rar file. I'm very surprised since rar is lossless and mp3/wmv is lossy and lossy usually compresses better than lossless. Why might this happen?

unrar -lt的输出:

UNRAR 5.71 freeware      Copyright (c) 1993-2019 Alexander Roshal

Archive: /private/var/root/Desktop/level-6.rar
Details: RAR 4

        Name: level-6.wma
        Type: File
        Size: 26237479
 Packed size: 17275823
       Ratio: 65%
       mtime: 2010-03-18 15:35:19,000000000
  Attributes: ..A....
       CRC32: 950CFA63
     Host OS: Windows
 Compression: RAR 3.0(v29) -m3 -md=4M
UNRAR 5.71 freeware      Copyright (c) 1993-2019 Alexander Roshal

Archive: /private/var/root/Desktop/HSK/H61001.rar
Details: RAR 4

        Name: H61001.mp3
        Type: File
        Size: 86448468
 Packed size: 40408917
       Ratio: 46%
       mtime: 2011-02-18 10:40:02,000000000
  Attributes: ..A....
       CRC32: 7C1319AB
     Host OS: Windows
 Compression: RAR 3.0(v29) -m3 -md=4M

ffprobe的输出:

Input #0, mp3, from '/private/var/root/Desktop/HSK/H61001.mp3':
  Metadata:
    album           : δ֪³ªÆ¬¼¯ (2010-9-13 8:32:01)
    title           : ÇúÄ¿ 1
    track           : 1
    genre           : δ֪
    artist          : δ֪ÒÕÊõ¼Ò
    TLEN            : 2162986
    id3v2_priv.AverageLevel: \x0b\x04\x00\x00
    id3v2_priv.PeakValue: \x1a9\x00\x00
  Duration: 00:36:01.11, start: 0.000000, bitrate: 320 kb/s
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 320 kb/s
Input #0, asf, from '/private/var/root/Desktop/HSK/level-6.wma':
  Metadata:
    WMFSDKNeeded    : 0.0.0.0000
    DeviceConformanceTemplate: L1
    WM/WMADRCPeakReference: 19841
    WM/WMADRCAverageReference: 1995
    WMFSDKVersion   : 9.00.00.4506
    IsVBR           : 0
  Duration: 00:36:10.67, start: 0.000000, bitrate: 96 kb/s
    Stream #0:0(chi): Audio: wmav2 (a[1][0][0] / 0x0161), 44100 Hz, 2 channels, fltp, 96 kb/s

ll(ls -G -lh)

total 630704
-rw-r--r--@ 1 root  staff    82M  2 18  2011 H61001.mp3
-rw-r--r--@ 1 root  staff   700K  2  7 16:15 H61001.pdf
-rw-r--r--@ 1 root  staff    39M  2  7 16:23 H61001.rar
-rw-r--r--@ 1 root  staff   729K  2  7 16:19 HSK-2012.xls
-rw-r--r--@ 1 root  staff   113M  2  7 16:20 HSK6.7z
-rw-r--r--@ 1 root  staff   1.2M  2  7 16:19 HSK6.pdf
-rw-r--r--@ 1 root  staff    16M  2  7 16:23 level-6.rar
-rw-r--r--@ 1 root  staff    25M  3 18  2010 level-6.wma
drwxr-xr-x@ 7 root  staff   224B  3 25  2016 六级录音

下载链接:

http://www.chinesetest.cn/userfiles/file/dagang/level-6.rar
http://www.chinesetest.cn/userfiles/file/HSK/level6/H61001.rar
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