Hi all,
I am Mohit, a GSoC student participant with BRL-CAD for the year 2013. My
GSoC-13 project was aimed to consolidate and develop an image processing
and conversion library.
To start my work, I adopted BRL-CAD's standard coding style, grasped
functions related to its utility library (libbu) and focused on the status
of image processing library previously in place (LIBICV). After which I
worked on the various tools of Image Processing in BRL-CAD and listed and
grouped them as per the processing they are involved in. Prior to my
application period and during very initial phase of coding period, I
created few patches to earn my commit rights. And was successfully granted
one on 26th July.
My first challenge was to decide on the image containers. After discussions
on mails and IRC. And writing some testing codes I along with my mentors
decided on the current image processing container. This included changing
the data type of the image data. Included new entries for number of
channels and other image rules. And the most important scrapping the file
descriptor used in the image containers. Thus the name also changed from
icv_image_file to icv_image. The data was no longer associated to a file
but rather an image.
Even bigger challenge was to incorporate these changes in the existing use
of the image processing library in the BRL-CAD utilities like rt and
libraries like ged and all. Also, I was strictly guided to adopt sequential
and minimal change during commits. This required exploring code base of rt
and other places where LIBICV was used. Later I completed the task with few
modifications and reiterations. This was challenging because rt follows
RTUIF (Ray-Tracing User Interface Framework ) involving many files
different functions and different privileges to use image reading/writing.
With few complications I was later successful in implementing the changes.
After coming to a standard implementation and setting the game rules right
other tasks were both easy and smooth. I wrote APIs for image processing of
functions including but not limited to convolution (also special
convolution including three images [icv_filter3] ), cropping (a special
cropping with any four points of a quadrilateral [icv_crop]), resizing
(with two ways to interpolate and two to decimate).
I also used these APIs in BRL-CAD's image processing tools and modified
there documentation pages when required.
Later I wrote the reading and writting plugin for different image formats.
Currently ICV has capibility to read/write images from/to both pipes and
files. Also In the case of BRL-CAD raw data of BW, PIX and DPIX the library
has an added capability to read without the size being specified. Other
implemented format is ppm.
Sean and Erik were great mentors. They would always guide and insist me on
adopting standard practices whose importance I realize now. Really
maintaining large and old code-bases is both fun and learning.
It was my first time in Open-Source Coding. I enjoyed and believe this
summer will be cherishable.
*Future Work*
In future I will be working on other formats. The whole point on adopting
the new image container was to use rt's capacities to render high quality
images and get an ability to store images of high definition format like
OpenEXR in BRL-CAD. Therefore I will be working on it.
--
*Mohit*
*IRC Nick : zero_level*
------------------------------------------------------------------------------
October Webinars: Code for Performance
Free Intel webinars can help you accelerate application performance.
Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from
the latest Intel processors and coprocessors. See abstracts and register >
http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk
_______________________________________________
BRL-CAD Developer mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/brlcad-devel
