With the switch of gstopencv.c to C++, all OpenCV elements are built with
g++. The template variable clashes with C++'s feature of the same name.
Rename template to templ to avoid any clash.
The cascade classifier changes its structure on new version of OpenCV.
The need to migrate to C++ to utilize the new load method of OpenCV which
allows to load the new classifiers.
https://bugzilla.gnome.org/show_bug.cgi?id=748377
The property level has a minimum value of 0. But when we set the level as 0,
it gets an assertion error. The function icvPyrSegmentation8uC3R returns false
if level is set as 0, since the minimum level cant be 0 and thus results in error.
Hence changing the minimum value to 1.
https://bugzilla.gnome.org/show_bug.cgi?id=749525
Variable hands is already checked to contain a value previously at the beginning
of the current block. There is no need to check again. This is logically dead code.
CID 1197693
If old opencv1-style legacy include directory is available,
this change becomes purely cosmetic (maybe will compile a bit faster).
It becomes an FTBFS fix when opencv1-style include directory is missing
(possibly because opencv package maintainer decided not to pack it).
https://bugzilla.gnome.org/show_bug.cgi?id=747705
If searchIdx() doesn't find the id it returns -1, which breaks
motioncelssvector.at (idx). Check for it and return if not found.
Changing a few other lines for style consistency.
Some variables are not initialized in the constructor. It is highly unlikely
they are used before being set, but it is safer to initialize them.
CID #1197704
Variable hands is already checked to contain a value previously at the beginning
of the current block (in line 504). There is no need to check again. This is
logically dead code.
CID 1197693
face detection will be performed only if image standard deviation is
greater that min-stddev. Default min-stddev is 0 for backward
compatibility. This property will avoid to perform face detection on
images with little changes improving cpu usage and reducing false
positives
https://bugzilla.gnome.org/show_bug.cgi?id=730510
templatematch operates on BGR data. In fact, OpenCV's IplImage always
stores color image data in BGR order -- this isn't documented at all in
the OpenCV source code, but there are hints around the web (see for
example
http://www.cs.iit.edu/~agam/cs512/lect-notes/opencv-intro/opencv-intro.html#SECTION00041000000000000000
and http://www.comp.leeds.ac.uk/vision/opencv/iplimage.html ).
gst_templatematch_load_template loads the template (the image to find)
from disk using OpenCV's cvLoadImage, so it is stored in an IplImage in
BGR order. But in gst_templatematch_chain, no OpenCV conversion
functions are used: the imageData pointer of the IplImage for the video
frame (the image to search in) is just set to point to the raw buffer
data. Without this fix, that raw data is in RGB order, so the call to
cvMatchTemplate ends up comparing the template's Blue channel against
the frame's Red channel, producing very poor results.
Previously changing the template property resulted in an exception
thrown from cvMatchTemplate, because "dist_image" (the intermediate
match-certainty-distribution) was the wrong size (because the
template image size had changed).
Locking has also been added to allow changing the properties (e.g. the
pattern to match) while the pipeline is playing.
* gst_element_post_message is moved outside of the lock, because it will
call into arbitrary user code (otherwise, if that user code calls into
gst_templatematch_set_property on this same thread it would deadlock).
* gst_template_match_load_template: If we fail to load the new template
we still unload the previous template, so this element becomes a no-op
in the pipeline. The alternative would be to keep the previous template;
I believe unloading the previous template is a better choice, because it
is consistent with the state this element would be in if it fails to
load the very first template at start-up.
Thanks to Will Manley for the bulk of this work; any errors are probably
mine.
The early return was bypassing the call to gst_pad_push. With no
filter->template (and thus no filter->cvTemplateImage) the rest of this
function is essentially a no-op (except for the call to gst_pad_push).
This (plus the previous commit) allows templatematch to be
enabled/disabled without removing it entirely from the pipeline, by
setting/unsetting the template property.
First this is handle by base transform, hence this is a no-op, and if it wasn't it
would lead to a buffer copy being leaked, and then an unreffed buffer being
pushed downstream.
https://bugzilla.gnome.org/show_bug.cgi?id=732756
