Name
fast_matchfast_matchFastMatchFastMatch — Searching all good matches of a template and an image.
Warning
fast_matchfast_matchFastMatchFastMatchFastMatch is obsolete and is only provided for
reasons of backward compatibility. New applications should use the
shape-based or NCC-based operators instead.
The operator fast_matchfast_matchFastMatchFastMatchFastMatch performs a matching of the
template of TemplateIDTemplateIDTemplateIDTemplateIDtemplateID and ImageImageImageImageimage.
Hereby the template will be moved over the points of
ImageImageImageImageimage so that the template always lies completely
inside of ImageImageImageImageimage.
The matching criterion (“displaced frame difference”)
is defined as follows:
The difference between fast_matchfast_matchFastMatchFastMatchFastMatch and exhaustive_matchexhaustive_matchExhaustiveMatchExhaustiveMatchExhaustiveMatch
is that the matching for one position is stopped if the error
is to high. This leads to a reduced runtime but one might
miss correct matches.
The runtime of the operator depends mainly on the size of the domain
of ImageImageImageImageimage.
Therefore it is important to restrict the domain as far as possible,
i.e. to apply the operator only in a very confined “region of interest”.
The parameter MaxErrorMaxErrorMaxErrorMaxErrormaxError determines the maximal error which the
searched position is allowed to show.
The lower this value is, the faster the operator runs.
All points which show a matching error smaller than
MaxErrorMaxErrorMaxErrorMaxErrormaxError will be returned in the output region
MatchesMatchesMatchesMatchesmatches.
This region can be used for further processing. For example by
using a connection and best_matchbest_matchBestMatchBestMatchBestMatch to find all the
matching objects. If no point has a match error below MaxErrorMaxErrorMaxErrorMaxErrormaxError
the empty region (i.e no points) is returned.
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Automatically parallelized on tuple level.
Input image inside of which the pattern has to
be found.
All points whose error lies below a certain threshold.
Maximal average difference of the grayvalues.
Default value: 20.0
Suggested values: 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 9.0, 11.0, 15.0, 17.0, 20.0, 30.0
Typical range of values: 0
≤
MaxError
MaxError
MaxError
MaxError
maxError
≤
255
Minimum increment: 1
Recommended increment: 1
If the parameter values are correct, the operator fast_matchfast_matchFastMatchFastMatchFastMatch
returns the value 2 (H_MSG_TRUE).
If the input is empty (no input images are available) the behaviour can
be set via set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>).
If necessary, an exception is raised.
create_templatecreate_templateCreateTemplateCreateTemplateCreateTemplate,
read_templateread_templateReadTemplateReadTemplateReadTemplate,
adapt_templateadapt_templateAdaptTemplateAdaptTemplateAdaptTemplate,
draw_regiondraw_regionDrawRegionDrawRegionDrawRegion,
draw_rectangle1draw_rectangle1DrawRectangle1DrawRectangle1DrawRectangle1,
reduce_domainreduce_domainReduceDomainReduceDomainReduceDomain
connectionconnectionConnectionConnectionConnection,
best_matchbest_matchBestMatchBestMatchBestMatch
best_matchbest_matchBestMatchBestMatchBestMatch,
best_match_mgbest_match_mgBestMatchMgBestMatchMgBestMatchMg,
fast_match_mgfast_match_mgFastMatchMgFastMatchMgFastMatchMg,
exhaustive_matchexhaustive_matchExhaustiveMatchExhaustiveMatchExhaustiveMatch,
exhaustive_match_mgexhaustive_match_mgExhaustiveMatchMgExhaustiveMatchMgExhaustiveMatchMg
Matching