{"id":1578,"date":"2013-10-25T18:05:06","date_gmt":"2013-10-25T17:05:06","guid":{"rendered":"https:\/\/ridgesolutions.ie\/?p=1578"},"modified":"2013-10-25T18:05:06","modified_gmt":"2013-10-25T17:05:06","slug":"ximea-xigetimage-fails-and-returns-11-xi_invalid_arg-on-xiq-usb3-camera","status":"publish","type":"post","link":"https:\/\/www.ridgesolutions.ie\/index.php\/2013\/10\/25\/ximea-xigetimage-fails-and-returns-11-xi_invalid_arg-on-xiq-usb3-camera\/","title":{"rendered":"XIMEA xiGetImage() fails and returns 11 (XI_INVALID_ARG) on xiQ USB3 Camera"},"content":{"rendered":"

If you are having problems with xiGetImage() sometimes failing and returning an error value of XI_INVALID_ARG (11) then it may be due to the state of the XI_IMG structure that you are passing into the call (the image pointer argument).<\/p>\n

The image object’s .size parameter must be set to sizeof(XI_IMG) and must not be 0. This is not really discussed in the XIMEA API documentation, but if it is left at 0 then the call will fail (however it doesn’t see to have to be sizeof(XI_IMG) for the call to work).<\/p>\n

So xiGetImage() should be called like this:<\/p>\n

\r\nXI_IMG image;\r\nimage.size = sizeof(XI_IMG); \/\/ Must initialise the .size field\r\nauto res = xiGetImage(handle, timeout, &image);\r\n<\/pre>\n
If you don’t initialize the .size field then you may get occasional fails depending on how the image struct is declared, for example if it is declared as a local variable on the stack then an un-initialised image struct will have random-ish values, the .size field is unlikely to be zero, but it may occasionally be zero and when it is the acquisition will fail.<\/p>\n
If however, the image struct is declared as a file static variable then it will always be initialised to 0, .size will always be 0 and the acquisition will always fail!<\/p>\n
So remember to always initialise it and you will save yourself lots of head-scratching!<\/p>\n","protected":false},"excerpt":{"rendered":"
If you are having problems with xiGetImage() sometimes failing and returning an error value of XI_INVALID_ARG (11) then it may be due to the state of the XI_IMG structure that you are passing into the call (the image pointer argument). The image object’s .size parameter must be set to sizeof(XI_IMG) and must not be 0. […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[290,289,291],"class_list":["post-1578","post","type-post","status-publish","format-standard","hentry","category-tech-stuff","tag-camera","tag-usb3","tag-ximea"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t