HALCON Extension Package Programmer's Manual

64 CHAPTER 5. HANDLING ICONIC OBJECTS AND CONTROL PARAMETERSÀÝ ÓÝÀÝ ÑÝÀÝ ÖÓÒÝÀÑ ÑÀÖÐÖÓÒ ÖÓÒºººÀØÓÑÔ´ÔÖÓÒиÓݸÁÅÁƸ²ÑݵÀØÓÑÔ´ÔÖÓÒиÓݸÊÁÇƸ²ÖÓÒݵÀØÁÑ´ÔÖÓÒиÑݸ²ÑµÀØÊÄ´ÔÖÓÒиÖÓÒݸÖÓÒµ×ÛØ ´ÑºÒµ ß× ÌÁÅ» ÔÖÓ××Ò ´Ò ÒÖÐ Ø× ×ÓÙÐ »» ÓÒ ÐÐÒ Ò ØÓÒ ÔÖÓÙÖµ »Ö ×ÙÑ ¼ÓÖ ´¼ ÖÓÒ¹ÒÙÑ ··µ ßÓÖ ´´ÖÓÒ¹Öи¸ÑºÛص´ÖÓÒ¹Öи¸ÑºÛص ··¸ Ö··µ×ÙÑ · ѺÔÜк℄ÐÚÖ ×ÙÑ » ÖÖÙÐØ ÖØÙÖÒ´ÀÊÊÏÁ̵ » ÛÖÓÒ Ñ ØÝÔ »ÐFigure 5.7: Example for ÀØÁÑ: Average gray value of first channel.raw data in ѺÔÜÐ. This is much more efficient, but means that only read access tothe image matrix is recommended (otherwise you will encounter unpredictable side effects).Fig. 5.7 shows an application of ÀØÁÑ.5.1.5 ÀØÄÀØÄ (see Fig. 5.1) is used to access XLD objects in the HALCON data base. The object ofinterest is specified by the data base key Ó Ý. The parameter ÜÐ ØÝÔ allows to specifythe kind of XLD data to be accessed: It has to be set to Ä ÇÆÌÇÍÊ Á in case of a contourand to Ä ÈÇÄÇÆ Á in case of a polygon. Corresponding to the selected type ÀØÄexpects a pointer to ÀÓÒØ or a pointer to ÀÔÓÐÝ in the parameter ÜÐ. In both cases notthe underlying data within the structures ÀÓÒØ or ÀÔÓÐÝ but only the pointers to the data arecopied from the data base. Thus, please avoid any write access to this data. Otherwise youwill encounter unpredictable side effects (changing other HALCON objects). Fig. 5.8 shows asimple example for how to use ÀØÄ.HALCON Extension Package Interface / 2000-11-16