Re: [pdf-devel] CCITT filter and pdf_stm_filter_apply pdf_stm_filter_get_input function and cache size in pdf_stm_buffer_t struct

[jemarch]

Hi Vivek.

   In pdf-stm-filter-apply function we are checking for the return
   value of filters's apply_fn. If the return value is PDF_ENINPUT the
   cache is refilled with encoded data if no other filters are present
   in the chain.

Right. If the return value of apply_fn is PDF_ENINPUT then the filter
tries to get more input data to process in the input buffer.

   In case of CCITT fax filter the data in the cache before it is
   refilled might be useful for properly decoding the data.

All of it? I mean, do you need to pass all the image data to libtiff
in just one call?

If that is the case, then you will need to cache all the incoming data
in an internal buffer (in the filter private data), returning
PDF_ENINPUT until you get finish_p or you find the EOL.