[ogg-dev] Fixing ogg vorbis corruption caused by bad metadata

[Monty Montgomery]

Vorbose -v reports the following for the beginning of the file:

INFO   page: Capture pattern OggS, format version 0
             Flags: first page of logical stream

             Granule position: 0x0000000000000000
             Stream serialno : 0x490f5cff
             Sequence number : 0
             Checksum        : 0xee9c02b9
             Total segments  : 1
             Total packets   : 1 completed
                              ( 30)

info header: Vorbis identification header parsed:
             Stream version     : 0
             Output channels    : 2
             Output sample rate : 44100 Hz
             Bitrate targets    : unset/224000/unset
             Block sizes        : 256/2048 samples

WARN stream: 53638 bytes of garbage before page 1

info stream: All identification header pages parsed.
             1 logical stream muxed in this link.

INFO   page: Capture pattern OggS, format version 0
             Flags: packet continued from previous page

             Granule position: 0x0000000000000000
             Stream serialno : 0x490f5cff
             Sequence number : 13
             Checksum        : 0xab096acc
             Total segments  : 6
             Total packets   : 1 completed (1 cont)
                              (255, 255, 255, 255, 255, 113)

In short, this file's Ogg encapsulation is corrupt.  There's no chance
of this being a vorbis_comment_add_tag() bug as that would be corrupt
data inside valid Ogg.  The Ogg structure itself is invalid here.

Monty