[Ffmpeg-devel] MP3 decode error

[Martin Fiedler]

Hi!

There seems to be an error in the MP3 decoder. Some low volume
parts of MP3s are decoded incorrectly. This problem doesn't
occur with other decoders -- both mpg123 and WinAMPs default
decoder (whatever it is based upon) work just fine.

According to the decoder's error messages (see below) and due
to the fact that the "high-precision/low-precision MPEG audio"
configure switch doesn't have any influence, I suspect that the
error is somewhere in the huffman decoder.

The problem can be heard at the end of
>
ftp://ftp.scene.org/pub/music/groups/uran97/034/%5Buran97_034%5D_02_dq_-_take_that.mp3
I also uploaded the last few kilobytes of this file to the
MPlayer FTP, the path is: /MPlayer/incoming/mp3_decode_error

I also noticed the same problem in
>
ftp://ftp.de.scene.org/pub/parties/2006/assembly06/demo/1995_by_kewlers_mfx.zip
(the very end of file data/VR078f.mp3)

Here's an output of the current SVN revision, 7750:

[martin at dothan ffmpeg]$ ./ffplay takethat.mp3
mdb:333, lastbuf:0 skiping granule 0
mdb:333, lastbuf:0 skiping granule 0
mdb:333, lastbuf:0 skiping granule 0
mdb:333, lastbuf:0 skiping granule 0
bits_left=652
bits_left=552
bits_left=628
bits_left=642
bits_left=611
bits_left=575
bits_left=662
bits_left=533
bits_left=645
bits_left=572
bits_left=670
bits_left=671
bits_left=561
bits_left=731
bits_left=806
bits_left=820
bits_left=899
bits_left=968
bits_left=1077
bits_left=965
bits_left=680
bits_left=957
bits_left=960
bits_left=1129
bits_left=1113
bits_left=1159
bits_left=1213
bits_left=1201
bits_left=1218
bits_left=1217
bits_left=1267
bits_left=1297
bits_left=1060
bits_left=1273
bits_left=968
bits_left=1361
bits_left=1271
bits_left=1313
bits_left=1068
bits_left=1353
bits_left=1316
bits_left=1353
bits_left=1333
bits_left=1100
bits_left=1519
bits_left=1533
bits_left=1407
bits_left=1454
bits_left=1598
bits_left=1580
bits_left=1264
bits_left=1352
bits_left=1677
bits_left=1673
bits_left=1384
bits_left=1424
bits_left=1726
bits_left=1733
bits_left=1677
bits_left=1392
bits_left=1795
bits_left=1839
bits_left=1845
bits_left=1859
bits_left=1894
overread, skip -6 enddists: -4 -4
overread, skip -5 enddists: -2 -2
bits_left=1551
overread, skip -5 enddists: -2 -2
overread, skip -9 enddists: -7 -7
overread, skip -5 enddists: -4 -4
bits_left=1564
overread, skip -10 enddists: -9 -9
overread, skip -7 enddists: -1 -1
overread, skip -9 enddists: -7 -7
bits_left=1851
bits_left=1894
overread, skip -9 enddists: -8 -8
overread, skip -7 enddists: -3 -3
bits_left=1878
overread, skip -5 enddists: -2 -2
overread, skip -7 enddists: -5 -5
bits_left=1935
overread, skip -7 enddists: -6 -6
overread, skip -5 enddists: -4 -4
overread, skip -5 enddists: -2 -2
bits_left=1906
overread, skip -5 enddists: -2 -2
overread, skip -5 enddists: -1 -1
bits_left=1905
overread, skip -8 enddists: -7 -7
overread, skip -5 enddists: -4 -4
overread, skip -7 enddists: -6 -6
bits_left=1894
overread, skip -7 enddists: -3 -3
overread, skip -9 enddists: -1 -1
overread, skip -6 enddists: -3 -3
bits_left=1916
overread, skip -7 enddists: -2 -2
overread, skip -7 enddists: -6 -6
bits_left=1937
overread, skip -5 enddists: -1 -1
overread, skip -7 enddists: -4 -4
overread, skip -7 enddists: -2 -2
bits_left=1872
overread, skip -5 enddists: -3 -3
overread, skip -9 enddists: -2 -2
overread, skip -7 enddists: -1 -1
bits_left=1885
overread, skip -6 enddists: -3 -3
overread, skip -6 enddists: -3 -3
bits_left=1866
overread, skip -7 enddists: -3 -3
overread, skip -8 enddists: -3 -3
bits_left=1566
overread, skip -8 enddists: -1 -1
overread, skip -7 enddists: -5 -5
overread, skip -9 enddists: -6 -6
bits_left=1874
overread, skip -7 enddists: -4 -4
bits_left=1922
overread, skip -5 enddists: -1 -1
overread, skip -7 enddists: -2 -2
overread, skip -5 enddists: -1 -1
bits_left=1888
overread, skip -6 enddists: -2 -2
overread, skip -7 enddists: -6 -6
bits_left=1884
overread, skip -7 enddists: -3 -3
overread, skip -7 enddists: -1 -1
overread, skip -7 enddists: -6 -6
bits_left=1904
overread, skip -5 enddists: -2 -2
bits_left=1905
overread, skip -5 enddists: -2 -2
overread, skip -7 enddists: -1 -1
bits_left=1917
overread, skip -9 enddists: -1 -1
overread, skip -10 enddists: -5 -5
bits_left=1969
overread, skip -7 enddists: -4 -4
overread, skip -7 enddists: -2 -2
overread, skip -7 enddists: -5 -5
bits_left=1905
overread, skip -7 enddists: -1 -1
overread, skip -9 enddists: -5 -5
bits_left=1908
overread, skip -5 enddists: -1 -1
overread, skip -9 enddists: -6 -6
bits_left=1978
overread, skip -9 enddists: -8 -8
overread, skip -5 enddists: -1 -1
bits_left=1986
overread, skip -5 enddists: -4 -4
bits_left=1986
overread, skip -9 enddists: -8 -8
overread, skip -7 enddists: -6 -6
bits_left=1626
overread, skip -9 enddists: -7 -7
overread, skip -5 enddists: -1 -1
bits_left=1643
overread, skip -9 enddists: -5 -5
bits_left=1947
overread, skip -7 enddists: -1 -1
overread, skip -9 enddists: -6 -6
overread, skip -8 enddists: -2 -2
bits_left=1989
overread, skip -7 enddists: -5 -5
overread, skip -7 enddists: -3 -3
overread, skip -9 enddists: -5 -5
bits_left=1996
overread, skip -8 enddists: -4 -4
overread, skip -10 enddists: -8 -8
bits_left=1996
bits_left=1982
overread, skip -8 enddists: -3 -3
bits_left=1975
overread, skip -6 enddists: -1 -1
overread, skip -5 enddists: -3 -3
bits_left=1944
overread, skip -9 enddists: -7 -7
bits_left=1977
overread, skip -5 enddists: -2 -2
bits_left=1980
overread, skip -7 enddists: -1 -1
overread, skip -7 enddists: -5 -5
bits_left=2004
overread, skip -5 enddists: -4 -4
overread, skip -8 enddists: -3 -3
bits_left=2010
overread, skip -9 enddists: -8 -8
bits_left=1968
overread, skip -7 enddists: -6 -6
overread, skip -7 enddists: -1 -1
bits_left=2006
overread, skip -7 enddists: -2 -2
bits_left=2047
overread, skip -5 enddists: -4 -4
bits_left=2007
overread, skip -5 enddists: -4 -4
overread, skip -7 enddists: -4 -4
bits_left=1998
overread, skip -5 enddists: -2 -2
bits_left=-2
bits_left=2032
overread, skip -7 enddists: -2 -2
overread, skip -9 enddists: -3 -3
bits_left=2021
overread, skip -7 enddists: -4 -4
overread, skip -9 enddists: -8 -8
bits_left=1672
overread, skip -9 enddists: -6 -6
bits_left=2035
overread, skip -7 enddists: -1 -1
overread, skip -7 enddists: -6 -6
bits_left=2071
overread, skip -8 enddists: -2 -2
overread, skip -5 enddists: -1 -1
bits_left=2031
overread, skip -9 enddists: -5 -5
bits_left=2027
overread, skip -5 enddists: -3 -3
bits_left=2028
overread, skip -5 enddists: -2 -2
bits_left=2036
overread, skip -7 enddists: -4 -4
bits_left=2074
overread, skip -9 enddists: -2 -2
bits_left=2087
overread, skip -9 enddists: -1 -1
bits_left=2070
overread, skip -9 enddists: -7 -7
bits_left=2082
overread, skip -10 enddists: -9 -9
overread, skip -5 enddists: -4 -4
bits_left=2119
bits_left=-6
bits_left=1751
bits_left=2119
overread, skip -5 enddists: -3 -3
bits_left=2096
bits_left=1735
overread, skip -5 enddists: -3 -3
bits_left=2118
overread, skip -9 enddists: -1 -1
bits_left=2122
overread, skip -7 enddists: -2 -2
bits_left=2110
overread, skip -7 enddists: -6 -6
bits_left=2137
bits_left=2123
overread, skip -9 enddists: -4 -4
bits_left=2147
overread, skip -4 enddists: -3 -3
overread, skip -6 enddists: -5 -5
bits_left=2147
overread, skip -5 enddists: -1 -1
bits_left=2134
bits_left=2128
overread, skip -9 enddists: -3 -3
bits_left=2158
overread, skip -4 enddists: -3 -3
bits_left=2151
bits_left=2171
bits_left=-5
bits_left=2217
bits_left=1847
bits_left=2232
bits_left=2230
bits_left=2236
overread, skip -4 enddists: -3 -3
bits_left=2267
bits_left=2256
overread, skip -4 enddists: -1 -1
overread, skip -4 enddists: -2 -2
bits_left=2288
overread, skip -4 enddists: -1 -1
bits_left=1914
bits_left=1925
bits_left=1934
overread, skip -4 enddists: -2 -2
overread, skip -4 enddists: -2 -2
bits_left=1946
overread, skip -4 enddists: -1 -1
bits_left=1970
overread, skip -4 enddists: -2 -2
bits_left=2363
bits_left=2376
bits_left=2426
overread, skip -4 enddists: -2 -2
bits_left=2443
bits_left=2514
bits_left=2520
[...] (repeats a few times)
bits_left=2520
invalid new backstep 519
bits_left=2520


- Martin J. Fiedler   [http://keyj.s2000.ws/]