The morph function lets you convolve the image with a kernel. It's
decently fast right now. But, in the future we'll have to optimize it by
a lot (unrolling loops, using SIMD instructions, etc.).
Anyway, along with morph I added an edge detection test script showing
how you can use a high pass filter on an image to get all the edges in
it. This is not as good as canny edge dection... but, it's about the
same and fast enough.
We'll need a Hough Transform system in the future to make edge dection
useful. Not sure how that will be implemented... so, that's going to be
far away for now.
The old code did not actually implement the errode anhd dilate kernels
correctly. However, it migh have been a little faster because it avoided
the boundary problem.
In the future we can optimize all the kernel code to have different loops
for doing the edges of image versus the center. But, for now, this is
good enough. QVGA color tracking with kernels will be slow, but, the
speed can be improved with QQVGA resolution. Using a 3x3 kernel is
plenty fast. Larger ones are slower.
I also added the ability for you to set the threshold for erode and
dialte. This lets you make the kenrel a little bit smarter so that it
won't errode or dilate a pixel unless the threshold is met. Meaning,
you'll be able to use erode to erode an image down to 1 pixel wide
lines.
All the work previously has been more or less leading up to supporting
this function. The line op function will open a file and execute a
function pointer on each line of the file opened to modify the frame
buffer.
It now figures out the file type from the file extension. If no file
extension is given it just saves the file as BMP if its not a JPEG image
or JPEG if it's a JPEG image. If you specify an extension and the file is
not of that type then it will give you an error.
The new test_save.py should run until you reach the JPEG image part
where it quits due to lack of JPEG support natively on OV7725 boards.
Maybe JPEG mode should be supoorted by just compressing pictures?
There's not a lot of actual functionality changes from the last commit.
However, switching the basic wrapper library to just long_jump on
failure and moving all the state info to structs required changes to all
the base functions in the last commit. The rest of the changes are to
link in the new functionality and to get the code to compile (usbdbg.c
edits).
Next I'll work on a function which abstracts the problem of opening an
image up and executing a line by line function op on it. I already
worked the code out for that. But, it's not in this commit to keep
things streamlined.
* With the new integral moving window we can support face detection,
keypoints and template matching on QVGA frames. However, it was only
implemented and tested for face detection.
* Increasing the max integral frame now for easier testing.