{"action":"opened","issue":{"url":"https://api.github.com/repos/mshabunin/test2/issues/148","labels_url":"https://api.github.com/repos/mshabunin/test2/issues/148/labels{/name}","comments_url":"https://api.github.com/repos/mshabunin/test2/issues/148/comments","events_url":"https://api.github.com/repos/mshabunin/test2/issues/148/events","html_url":"https://github.com/mshabunin/test2/issues/148","id":96585725,"number":148,"title":"cvFindExtrinsicCameraParams2 produces inaccurate results when given 2D objectPoints","user":{"login":"opencv-pushbot","id":2051563,"avatar_url":"https://avatars.githubusercontent.com/u/2051563?v=3","gravatar_id":"","url":"https://api.github.com/users/opencv-pushbot","html_url":"https://github.com/opencv-pushbot","followers_url":"https://api.github.com/users/opencv-pushbot/followers","following_url":"https://api.github.com/users/opencv-pushbot/following{/other_user}","gists_url":"https://api.github.com/users/opencv-pushbot/gists{/gist_id}","starred_url":"https://api.github.com/users/opencv-pushbot/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/opencv-pushbot/subscriptions","organizations_url":"https://api.github.com/users/opencv-pushbot/orgs","repos_url":"https://api.github.com/users/opencv-pushbot/repos","events_url":"https://api.github.com/users/opencv-pushbot/events{/privacy}","received_events_url":"https://api.github.com/users/opencv-pushbot/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/mshabunin/test2/labels/auto-transferred","name":"auto-transferred","color":"ededed"},{"url":"https://api.github.com/repos/mshabunin/test2/labels/bug","name":"bug","color":"fc2929"},{"url":"https://api.github.com/repos/mshabunin/test2/labels/category:%203d","name":"category: 3d","color":"ededed"},{"url":"https://api.github.com/repos/mshabunin/test2/labels/category:%20calibration","name":"category: calibration","color":"ededed"},{"url":"https://api.github.com/repos/mshabunin/test2/labels/priority:%20normal","name":"priority: normal","color":"ededed"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2015-07-22T14:45:53Z","updated_at":"2015-07-22T14:45:53Z","closed_at":null,"body":"Transferred from http://code.opencv.org/issues/2143\r\n```\n|| dima kogan on 2012-07-04 18:47\n|| Priority: Normal\n|| Affected: None\n|| Category: calibration, 3d\n|| Tracker: Bug\n|| Difficulty: None\n|| PR: None\n|| Platform: None / None\n```\n\ncvFindExtrinsicCameraParams2 produces inaccurate results when given 2D objectPoints\n-----------\n```\nIf I call cvFindExtrinsicCameraParams2() and pass it 2D objectPoints, I\r\nexpect the routine to assume a planar object with z==0. Instead, z = 1 is\r\nused; this is done with this line in the implementation of\r\ncvFindExtrinsicCameraParams2():\r\n\r\n  cvConvertPointsHomogeneous( objectPoints, matM );\r\n\r\nIt makes no sense to convert the objectPoints matrix to homogeneous\r\ncoordinates, as this data lives in a completely different coordinate\r\nsystem from the camera observing the object.\r\n\r\nLooking a bit closer, it appears that the documentation of this function\r\nclaims to support ONLY 3D data for this matrix. Thus maybe the fix is to\r\nsimply enforce 3D input, which would make this issue moot. This would\r\nhandle bug #1875 as well.\r\n\r\nThanks\n```\n\nHistory\n-------\n##### Andrey Kamaev on 2012-07-09 11:43\n```\n-   Category set to calibration, 3d\n```"}}