> I'm writing DCT filter.I've some issues to discuss with you.
>
> 1. For the base layer, should the input and output be file or memory? Or
> both?
>
> 2. How to get the parameters for encode, e.g. the image size? If in the
hash
> table filter_params, should I add the key name of the parameters in
> pdf-stm.h?
>
Hi Yank, for both questions I recommend you to read some already implemented
filter like, pdf-f-ahex. I'll give you some hints anyways.
The input and output are two buffers, whether on disk or memory should not
be of
your concern.
You can read more here:
http://gnupdf.org/Lib:Architecture/Base_Layer/Stream_Module#Buffers
Regarding the parameters you only ask for the key, as it's supposed to be
already
added prior the filter's call.
You can see an example on the use of pdf_hash_t to hold the filter's
parameters in the JBIG2 decoder (src/base/pdf-stm-f-jbig2.[ch]).
