[vorbis-dev] Small files encoding problem

[Michael Smith]

On Wednesday 02 July 2003 19:42, Rany. wrote:
> I must compress some thousands of very small WAV samples. I compressed them
> with OGG and got a very strange result:
>
> uncompressed WAV size is 1 kb,
> and compressed OGG size is 3 kb.
>
> (I tried a minimal quality settings (--managed -m 16 -M 16 -b 16))
>
> Is this a bug, or OGG file header is so huge?
> Is there any way to compress such a small files?
>

Yes, this is one downside of the vorbis bitstream format - it includes large 
headers (several kB). 

There may or may not be things you can do about this, depending on what you're 
using it for. If you want normal ogg files as output, then you're pretty much 
stuck - that's how the format works. However, if you're doing this for use in 
an application-specific way, and you have control over the application, there 
are several things you could do.

The headers are the same every time (assuming you're using the same encoder 
with the same settings), so you could just save a single copy of the headers, 
then, on decoding, supply this header to the decoder along with the actual 
compressed data. Obviously, then, you don't have standard ogg files, but this 
is pretty easy to implement and use in some circumstances.

Mike

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