[Bf-committers] Cineon/DPX speed up

[Julien Enche]

Hi all,

I've been looking to improve speed of Cineon/DPX files loading as larger 
images can take quite some time to display, and even more if a log/RGB 
conversion is performed.

But before going any further and breaking things, I have 2 questions :

1) At the moment, the IB_test flag is not taken in account in the 
imb_load_dpx_cineon function, so color conversion happens twice. I 
haven't really find out what should be done and what can be skipped when 
this flag is set. Can you give me more information on the purpose of 
this flag so that I could adapt the code to use it efficiently (and safely).

2) It also turns out that the call to IMB_rect_from_float takes a lot of 
time. According to a comment found in the OpenEXR loading code, it 
doesn't seem to be needed (comment from OpenEXR code: "(...) ideally 
IM_rect would be used when the caller wants a rect BUT at the moment all 
functions use IM_rect. Disabling this is ok because all functions should 
check if a rect exists and create one on demand.").
Would it be safe to remove this call for Cineon/DPX ?

Julien