[vorbis-dev] oggenc broken for some types of WAV files

[Michael Smith]

The attached audio.c is significantly different from what the patch
you sent the other day did. I haven't checked it yet carefully, the 
really obvious bugs are no longer present.

>
>The bottom line is that there will be WAV files with 16 byte format tags, and 18 byte format tags, possibly
>with abitrarily long numbers of addtional bytes following the format tag.
>
>Even if the WAV file in question was not exactly conforming to the spec, I believe in a design
>philosophy of software being able to tolerate, within reason, input which is not 
>exactly to-spec, *especially* if your competition's software does.  (The WAV file in question works
>with Winamp, Microsoft media player, and serveral MP3 encoders.)

'within reason'. Yes. Allowing sillyness like this, however, just makes
the program far less error-tolerant.

>
>For example, most HTML documents are not strictly conforming to spec, but most browsers will
>display the content anyway.  
>
>>There's already a
>>special case for allowing the "fmt " chunk to be of length 18 - this is
>>incorrect according to every wav spec I've been able to find, but is 
>>common. 
>
>It's not incorrect, see above.
>
>>However, allowing arbitrarily long fmt chunks is definately not
>>a good idea, 
>>so I won't be changing this behaviour unless you can show
>>me an official wav spec that says this is allowed. 
>
>It is allowed, the official spec is attached.

See below. This isn't even pretending to be a spec.

>
>>
>>The application that is creating these files is presumably buggy.
>>
>No.  It conforms to the spec, why presume it's someone else?

As I said, every spec I've seen explicitly disallows this. You attached
API documentation, which covers in-memory data structures. I was looking
for _file format_ documentation, something which is completely 
different.

It seems quite clearly a violation of the spec. The program creating
them _is_ buggy. 

However, in the interests of compatibility with stupidity, I've made
the changes, though I've left a strong warning against using the program
creating them in there, since it's wrong.

Michael

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