Re: [pdf-devel] [patch] convert LZW filter to new API

[Brad Hards]

On Thursday 25 June 2009 05:23:47 am Juan Pedro Bolivar Puente wrote:
> Btw, I am updating my old patch to the current state of the gnupdf code.
> I'm using Brad's unit tests to try the LZW filter implementation and on
> decoding I'm missing the last character. After some debugging I found
> that the filter is never reaching the EOD code and I'm wondering wether
> the test case is ok.
I think the test case is OK. It is directly from the PDF specification, so the 
test data should be OK. I could, of course, have made an error in the 
implementation.

Both decode and encode work with my patch (excluding the buffer size issue, 
which I'm not sure I fully understand - there is a fixed overhead associated 
with the initialization and the 9-bit symbols, and you can't avoid the output 
growing in this case).

> I'm going to do further testing tomorrow with 
> pdf-filter to better test encoding too (in the test case you're checking
> against a match at a fixed length, but the actual generated output may
> be longer).
I guess I should have resized the output?

> If Brad agrees I can try to fix the cache needs problem and send a patch
> in few days -this time I won't dissapear, I promise :p.
I'm more than happy for you to work on this. Feel free to use whatever makes 
sense (to you) from your current code and mine.

Brad