best_match_mgT_best_match_mgBestMatchMgBestMatchMgbest_match_mg (Operator)
Name
best_match_mgT_best_match_mgBestMatchMgBestMatchMgbest_match_mg — Searching the best gray value matches in a pyramid.
Warning
best_match_mgbest_match_mgBestMatchMgBestMatchMgbest_match_mg is obsolete and is only provided for
reasons of backward compatibility. New applications should use the
shape-based or NCC-based operators instead.
Signature
void BestMatchMg(const HObject& Image, const HTuple& TemplateID, const HTuple& MaxError, const HTuple& SubPixel, const HTuple& NumLevels, const HTuple& WhichLevels, HTuple* Row, HTuple* Column, HTuple* Error)
void HTemplate::BestMatchMg(const HImage& Image, double MaxError, const HString& SubPixel, Hlong NumLevels, const HTuple& WhichLevels, double* Row, double* Column, double* Error) const
void HTemplate::BestMatchMg(const HImage& Image, double MaxError, const HString& SubPixel, Hlong NumLevels, Hlong WhichLevels, double* Row, double* Column, double* Error) const
void HTemplate::BestMatchMg(const HImage& Image, double MaxError, const char* SubPixel, Hlong NumLevels, Hlong WhichLevels, double* Row, double* Column, double* Error) const
void HTemplate::BestMatchMg(const HImage& Image, double MaxError, const wchar_t* SubPixel, Hlong NumLevels, Hlong WhichLevels, double* Row, double* Column, double* Error) const
(
Windows only)
void HImage::BestMatchMg(const HTemplate& TemplateID, double MaxError, const HString& SubPixel, Hlong NumLevels, const HTuple& WhichLevels, double* Row, double* Column, double* Error) const
void HImage::BestMatchMg(const HTemplate& TemplateID, double MaxError, const HString& SubPixel, Hlong NumLevels, Hlong WhichLevels, double* Row, double* Column, double* Error) const
void HImage::BestMatchMg(const HTemplate& TemplateID, double MaxError, const char* SubPixel, Hlong NumLevels, Hlong WhichLevels, double* Row, double* Column, double* Error) const
void HImage::BestMatchMg(const HTemplate& TemplateID, double MaxError, const wchar_t* SubPixel, Hlong NumLevels, Hlong WhichLevels, double* Row, double* Column, double* Error) const
(
Windows only)
static void HOperatorSet.BestMatchMg(HObject image, HTuple templateID, HTuple maxError, HTuple subPixel, HTuple numLevels, HTuple whichLevels, out HTuple row, out HTuple column, out HTuple error)
void HTemplate.BestMatchMg(HImage image, double maxError, string subPixel, int numLevels, HTuple whichLevels, out double row, out double column, out double error)
void HTemplate.BestMatchMg(HImage image, double maxError, string subPixel, int numLevels, int whichLevels, out double row, out double column, out double error)
void HImage.BestMatchMg(HTemplate templateID, double maxError, string subPixel, int numLevels, HTuple whichLevels, out double row, out double column, out double error)
void HImage.BestMatchMg(HTemplate templateID, double maxError, string subPixel, int numLevels, int whichLevels, out double row, out double column, out double error)
Description
best_match_mgbest_match_mgBestMatchMgBestMatchMgbest_match_mg applies gray value matching using an
image pyramid.
best_match_mgbest_match_mgBestMatchMgBestMatchMgbest_match_mg works analogously to best_matchbest_matchBestMatchBestMatchbest_match,
but it is faster due to the use of a pyramid.
Input is an image with an optionally reduced domain. The template is
searched within those points of the domain of the image, in which
the model lies completely within the image. This means that the
model will not be found if it extends beyond the borders of the
image. The parameter MaxErrorMaxErrorMaxErrormaxErrormax_error specifies the maximum error
for template matching.
Using smaller values results in a reduced runtime but it is possible
that the pattern might be missed.
The value of MaxErrorMaxErrorMaxErrormaxErrormax_error has to be chosen larger compared with
best_matchbest_matchBestMatchBestMatchbest_match, because the error at higher levels
of the pyramid is often larger.
SubPixelSubPixelSubPixelsubPixelsub_pixel specifies if the result is calculated
with sub pixel accuracy or not.
A value of 1 for NumLevelsNumLevelsNumLevelsnumLevelsnum_levels
results in an operator similar to best_matchbest_matchBestMatchBestMatchbest_match,
i.e. only the original gray values are used.
For values larger than 1,
the algorithm starts at the lowest resolution and searches
for a position with the lowest matching error.
At the next higher resolution this position is refined.
This is continued up to the maximum resolution
(WhichLevelsWhichLevelsWhichLevelswhichLevelswhich_levels = 'all'"all""all""all""all").
As an alternative Method the mode
WhichLevelsWhichLevelsWhichLevelswhichLevelswhich_levels with value 'original'"original""original""original""original" can be used.
In this case not only the position with the lowest error
but all points below MaxErrorMaxErrorMaxErrormaxErrormax_error are analyzed further on
in the next higher resolution.
This method is slower but it is more stable and the possibility
to miss the correct position is very low.
In this case it is often possible to start with a lower resolution (higher
level in Pyramid, i.e. larger value for NumLevelsNumLevelsNumLevelsnumLevelsnum_levels)
which leads to a reduced runtime.
Besides the values 'all'"all""all""all""all" and 'original'"original""original""original""original"
for WhichLevelsWhichLevelsWhichLevelswhichLevelswhich_levels
you can specify the pyramid level explicitly
where to switch between a “match all” and the ”best match”.
Here 0 corresponds to 'original'"original""original""original""original"
and NumLevelsNumLevelsNumLevelsnumLevelsnum_levels - 1 is equivalent to 'all'"all""all""all""all". A value
in-between is in most cases a good compromise between speed
and a stable detection. A larger value for WhichLevelsWhichLevelsWhichLevelswhichLevelswhich_levels
results in a reduced runtime, a smaller value
results in a more stable detection.
The value of NumLevelsNumLevelsNumLevelsnumLevelsnum_levels has to be equal or smaller than
the value used to create the template.
The position of the found matching position is
returned in RowRowRowrowrow and ColumnColumnColumncolumncolumn.
The corresponding error is given in ErrorErrorErrorerrorerror.
If no point below MaxErrorMaxErrorMaxErrormaxErrormax_error is found
a value of 255 for ErrorErrorErrorerrorerror and
0 for RowRowRowrowrow and ColumnColumnColumncolumncolumn
is returned. If the desired object is missed (no object found
or wrong position) you have to set MaxErrorMaxErrorMaxErrormaxErrormax_error higher
or WhichLevelsWhichLevelsWhichLevelswhichLevelswhich_levels lower. Check also if the
illumination has changed (see set_offset_templateset_offset_templateSetOffsetTemplateSetOffsetTemplateset_offset_template).
The maximum error of the position (without noise) is 0.1 pixel.
The average error is 0.03 pixel.
Execution Information
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Automatically parallelized on tuple level.
Parameters
ImageImageImageimageimage (input_object) singlechannelimage(-array) → objectHImageHObjectHObjectHobject (byte)
Input image inside of which the pattern has to
be found.
TemplateIDTemplateIDTemplateIDtemplateIDtemplate_id (input_control) template → HTemplate, HTupleHHandleHTupleHtuple (handle) (IntPtr) (HHandle) (handle)
Template number.
MaxErrorMaxErrorMaxErrormaxErrormax_error (input_control) real → HTuplefloatHTupleHtuple (real) (double) (double) (double)
Maximal average difference of the gray values.
Default:
30.0
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, 40.0, 50.0, 60.0, 70.0
Value range:
0
≤
MaxError
MaxError
MaxError
maxError
max_error
≤
255
Minimum increment:
1
Recommended increment:
3
SubPixelSubPixelSubPixelsubPixelsub_pixel (input_control) string → HTuplestrHTupleHtuple (string) (string) (HString) (char*)
Exactness in subpixels in case of 'true'"true""true""true""true".
Default:
'false'
"false"
"false"
"false"
"false"
List of values:
'false'"false""false""false""false", 'true'"true""true""true""true"
NumLevelsNumLevelsNumLevelsnumLevelsnum_levels (input_control) integer → HTupleintHTupleHtuple (integer) (int / long) (Hlong) (Hlong)
Number of the used resolution levels.
Default:
4
Suggested values:
1, 2, 3, 4, 5, 6
WhichLevelsWhichLevelsWhichLevelswhichLevelswhich_levels (input_control) integer → HTupleUnion[str, int]HTupleHtuple (integer / string) (int / long / string) (Hlong / HString) (Hlong / char*)
Resolution level up to which the
method “best match” is used.
Default:
2
Suggested values:
'all'"all""all""all""all", 'original'"original""original""original""original", 0, 1, 2, 3, 4, 5, 6
RowRowRowrowrow (output_control) point.y → HTuplefloatHTupleHtuple (real) (double) (double) (double)
Row position of the best match.
ColumnColumnColumncolumncolumn (output_control) point.x → HTuplefloatHTupleHtuple (real) (double) (double) (double)
Column position of the best match.
ErrorErrorErrorerrorerror (output_control) real → HTuplefloatHTupleHtuple (real) (double) (double) (double)
Average divergence of the gray values in the
best match.
Result
If the parameter values are correct, the operator best_match_mgbest_match_mgBestMatchMgBestMatchMgbest_match_mg
returns the value 2 (
H_MSG_TRUE)
.
If the input is empty (no input images are available) the behavior 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>)set_system("no_object_result",<Result>).
If necessary, an exception is raised.
Possible Predecessors
create_templatecreate_templateCreateTemplateCreateTemplatecreate_template,
read_templateread_templateReadTemplateReadTemplateread_template,
adapt_templateadapt_templateAdaptTemplateAdaptTemplateadapt_template,
draw_regiondraw_regionDrawRegionDrawRegiondraw_region,
draw_rectangle1draw_rectangle1DrawRectangle1DrawRectangle1draw_rectangle1,
reduce_domainreduce_domainReduceDomainReduceDomainreduce_domain,
set_reference_templateset_reference_templateSetReferenceTemplateSetReferenceTemplateset_reference_template,
set_offset_templateset_offset_templateSetOffsetTemplateSetOffsetTemplateset_offset_template
Alternatives
fast_matchfast_matchFastMatchFastMatchfast_match,
fast_match_mgfast_match_mgFastMatchMgFastMatchMgfast_match_mg,
best_matchbest_matchBestMatchBestMatchbest_match,
best_match_pre_mgbest_match_pre_mgBestMatchPreMgBestMatchPreMgbest_match_pre_mg,
best_match_rotbest_match_rotBestMatchRotBestMatchRotbest_match_rot,
best_match_rot_mgbest_match_rot_mgBestMatchRotMgBestMatchRotMgbest_match_rot_mg,
exhaustive_matchexhaustive_matchExhaustiveMatchExhaustiveMatchexhaustive_match,
exhaustive_match_mgexhaustive_match_mgExhaustiveMatchMgExhaustiveMatchMgexhaustive_match_mg
Module
Matching