Bug report: packMP3 on special files

[M-Gonzalo]

There's a particular file from a podcast at https://fossa.com/blog/fossa-podcast-adopting-haskell where precomp repeatedly tries and fails to process it as a whole, falling back to starting again at the offset of the part it could actually compress. This creates an unwanted slowdown.
It might be a special file structure with markers for the 15 sec steps of the web player. This is consisting with the valid chunks having similar lengths.

(96.75%) Possible MP3 found at position 43490661, length 1458678
Too much garbage data at the end, retry with new length 107834
Best match: 107834 bytes, recompressed to 103903 bytes
(96.99%) Possible MP3 found at position 43598495, length 1350844
Too much garbage data at the end, retry with new length 111177
Best match: 111177 bytes, recompressed to 106704 bytes
(97.24%) Possible MP3 found at position 43709672, length 1239667
Too much garbage data at the end, retry with new length 117028
Best match: 117028 bytes, recompressed to 112024 bytes
(97.50%) Possible MP3 found at position 43826700, length 1122639
Too much garbage data at the end, retry with new length 112013
Best match: 112013 bytes, recompressed to 107005 bytes
(97.75%) Possible MP3 found at position 43938713, length 1010626
Too much garbage data at the end, retry with new length 109924
Best match: 109924 bytes, recompressed to 105684 bytes
(98.00%) Possible MP3 found at position 44048637, length 900702
Too much garbage data at the end, retry with new length 116610
Best match: 116610 bytes, recompressed to 111178 bytes
(98.26%) Possible MP3 found at position 44165247, length 784092
Too much garbage data at the end, retry with new length 110760
Best match: 110760 bytes, recompressed to 106490 bytes
(98.50%) Possible MP3 found at position 44276007, length 673332
Too much garbage data at the end, retry with new length 109087
Best match: 109087 bytes, recompressed to 104735 bytes
(98.74%) Possible MP3 found at position 44385094, length 564245
Too much garbage data at the end, retry with new length 109923
Best match: 109923 bytes, recompressed to 105901 bytes
(98.99%) Possible MP3 found at position 44495017, length 454322
Best match: 454322 bytes, recompressed to 402117 bytes
New size: 42897489 instead of 44949339     

Done.
Time: 27 second(s), 650 millisecond(s)

Recompressed streams: 392/540
MP3 streams: 392/540

You can speed up Precomp for THIS FILE with these parameters:
-d0
precomp -cn -t+3 -v -e fossa-podcast-ep-001-draft-1.mp3

File downloaded using the DownThemAll Firefox extrension.