{"id":45859,"date":"2021-12-22T22:00:00","date_gmt":"2021-12-22T13:00:00","guid":{"rendered":"https:\/\/www.charlezz.com\/?p=45859"},"modified":"2021-12-22T23:21:12","modified_gmt":"2021-12-22T14:21:12","slug":"%ec%95%88%eb%93%9c%eb%a1%9c%ec%9d%b4%eb%93%9c%eb%a1%9c-%eb%b0%b0%ec%9a%b0%eb%8a%94-opencv-%eb%ac%b8%ec%84%9c%eb%aa%85%ed%95%a8-%ec%9d%b8%ec%8b%9d%ea%b8%b0-%eb%a7%8c%eb%93%a4%ea%b8%b0","status":"publish","type":"post","link":"https:\/\/charlezz.com\/?p=45859","title":{"rendered":"[\uc548\ub4dc\ub85c\uc774\ub4dc\ub85c \ubc30\uc6b0\ub294 OpenCV] \ubb38\uc11c(\uba85\ud568) \uc778\uc2dd\uae30 \ub9cc\ub4e4\uae30"},"content":{"rendered":"\n

Prerequisite : \uc774\ubbf8\uc9c0\uc758 \uc774\uc9c4\ud654<\/strong><\/a>, \uc724\uacfd\uc120 \uac80\ucd9c<\/a>, \uc724\uacfd\uc120 \uadfc\uc0ac\ud654<\/a>, \ud22c\uc2dc \ubcc0\ud658<\/a>, OCR<\/p>\n\n\n\n

\uac1c\uc694<\/h2>\n\n\n\n
\"\"
\uad6c\uae00 \ud50c\ub808\uc774\uc2a4\ud1a0\uc5b4\uc758 CamScanner \uc2a4\ud06c\ub9b0\uc0f7<\/em><\/figcaption><\/figure>\n\n\n\n

\uc774\ubc88 \uc7a5\uc5d0\uc11c\ub294 \uac04\ub2e8\ud55c \ubb38\uc11c \uc778\uc2dd \uc571\uc744 \ub9cc\ub4e4\uc5b4\ubcf8\ub2e4. \ud604\uc7ac\uae4c\uc9c0 \uacf5\ubd80\ud55c \ub0b4\uc6a9\uc744 \uc798 \uc9dc\uc9d1\uae30 \ud558\uba74 \ub9cc\ub4e4 \uc218 \uc788\ub294 \ub0b4\uc6a9\uc774\ub2e4. \ud558\ub098\uc529 \ubd84\ud560 \uc815\ubcf5\uc744 \ud1b5\ud574 \ubaa9\ud45c\uc5d0 \uc811\uadfc\ud574\ubcf4\uc790.<\/p>\n\n\n\n

Divide n Conquer<\/h2>\n\n\n\n

\uc704 \uadf8\ub9bc\uacfc \uac19\uc740 \uc571\uc744 \ub9cc\ub4e4\uae30 \uc704\ud574\uc11c\ub294 \ub2e4\uc74c\uacfc \uac19\uc740 \uacfc\uc815\uc744 \uac70\uccd0\uc57c \ud55c\ub2e4.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

1. \uc774\uc9c4\ud654<\/h2>\n\n\n\n

\uc774\uc9c4\ud654\ub97c \uc704\ud574\uc11c \uc6d0\ubcf8 \uc601\uc0c1\uc744 \uba3c\uc800 \ud751\ubc31\uc601\uc0c1\uc73c\ub85c \ubcc0\ud658\ud55c\ub2e4. \uadf8\ub7f0 \ub4a4 threshold \ud568\uc218\ub97c \uc0ac\uc6a9\ud558\uc5ec Otsu \uc774\uc9c4\ud654\ub97c \ub2e4\uc74c\uacfc \uac19\uc774 \uc801\uc6a9\ud560 \uc218 \uc788\ub2e4.<\/p>\n\n\n\n

val src:Mat = ... \/\/ \uc6d0\ubcf8\uc601\uc0c1 \n\n\/\/ \ud751\ubc31\uc601\uc0c1\uc73c\ub85c \uc804\ud658\nval graySrc = Mat()\nImgproc.cvtColor(src, graySrc, Imgproc.COLOR_BGR2GRAY<\/em>)\n\n\/\/ \uc774\uc9c4\ud654\nval binarySrc = Mat()\nImgproc.threshold(graySrc, binarySrc, 0.0, 255.0, Imgproc.THRESH_OTSU<\/em>)<\/pre>\n\n\n\n
2. \uc724\uacfd\uc120 \ucc3e\uae30<\/h2>\n\n\n\n
\uba3c\uc800 \uc724\uacfd\uc120\uc744 \uac80\ucd9c\ud558\uae30 \uc704\ud574 findContours \ud568\uc218\ub97c \ub2e4\uc74c\uacfc \uac19\uc774 \ud638\ucd9c \ud560 \uc218 \uc788\ub2e4.<\/p>\n\n\n\n
\/\/ \uc724\uacfd\uc120 \ucc3e\uae30
val contours = ArrayList<MatOfPoint>()
val hierarchy = Mat()
Imgproc.findContours(
    binarySrc,
    contours,
    hierarchy,
    Imgproc.RETR_EXTERNAL<\/em>,
    Imgproc.CHAIN_APPROX_NONE
<\/em>)<\/pre>\n\n\n\n
\ud558\uc9c0\ub9cc \uc724\uacfd\uc120\uc774 \uc5ec\ub7ec\uac1c \uac80\ucd9c\ub420 \uac00\ub2a5\uc131\uc774 \ub192\uc73c\ubbc0\ub85c, \uc6d0\ud558\ub294 \uc601\uc5ed\uc758 \uc724\uacfd\uc120\uc744 \ud544\ud130\ub9c1 \ud558\uae30 \uc704\ud574 \uba87\uac00\uc9c0 \uc870\uac74\ub4e4\uc744 \uc124\uc815\ud55c\ub2e4.<\/p>\n\n\n\n
1) \uac00\uc7a5 \uba74\uc801\uc774 \ud070 \uc724\uacfd\uc120\u001c\uac80\ucd9c\ud558\uae30<\/h3>\n\n\n\n
\uc77c\ubc18\uc801\uc73c\ub85c \uac80\ucd9c\ud558\uace0\uc790 \ud558\ub294 \uac1d\uccb4(\ubb38\uc11c)\ub97c \uac00\uc7a5 \ud070 \ud53c\uc0ac\uccb4\ub85c \ub450\uae30 \ub54c\ubb38\uc5d0 \uac00\uc7a5 \ud070 \uba74\uc801\uc744 \uac16\ub294 \uc724\uacfd\uc120\uc744 \uac80\ucd9c\ud55c\ub2e4.<\/p>\n\n\n\n
\/\/ \uac00\uc7a5 \uba74\uc801\uc774 \ud070 \uc724\uacfd\uc120 \ucc3e\uae30\nvar biggestContour: MatOfPoint? = null\nvar biggestContourArea: Double = 0.0\nfor (contour in contours) {\n    val area = Imgproc.contourArea(contour)\n    if (area > biggestContourArea) {\n        biggestContour = contour\n        biggestContourArea = area\n    }\n}\n\nif (biggestContour == null) {\n    throw IllegalArgumentException(\"No Contour\")\n}\n\/\/ \ub108\ubb34 \uc791\uc544\ub3c4 \uc548\ub428\nif (biggestContourArea < 400) {\n    throw IllegalArgumentException(\"too small\")\n}<\/pre>\n\n\n\n
2) \uadfc\uc0ac\ud654\ud558\uae30<\/h3>\n\n\n\n
\uc724\uacfd\uc120 \uadfc\uc0ac\ud654\ub97c \ud1b5\ud574 \ub3c4\ud615\uc758 \uaf2d\uc9d3\uc810\uc744 \ubd84\uba85\ud558\uac8c \ud558\uc790.<\/p>\n\n\n\n
val candidate2f = MatOfPoint2f(*biggestContour.toArray())
val approxCandidate = MatOfPoint2f()
Imgproc.approxPolyDP(
    candidate2f,
    approxCandidate,
    Imgproc.arcLength(candidate2f, true) * 0.02,
    true
)<\/pre>\n\n\n\n
3) \uc0ac\uac01\ud615\uc778\uc9c0 \ud310\ubcc4\ud558\uae30<\/h3>\n\n\n\n
\ubb38\uc11c\ub294 \uc77c\ubc18\uc801\uc73c\ub85c \uc0ac\uac01\ud615\uc774\ubbc0\ub85c \uadfc\uc0ac\ud654 \ud55c \uc724\uacfd\uc120\uc774 \uc0ac\uac01\ud615\uc778\uc9c0 \ud310\ubcc4\ud558\uc790.<\/p>\n\n\n\n
\/\/ \uc0ac\uac01\ud615 \ud310\ubcc4\nif (approxCandidate.rows() != 4) {\n    throw java.lang.IllegalArgumentException(\"It's not rectangle\")\n}\n\n\/\/ \ucee8\ubca1\uc2a4(\ubcfc\ub85d\ud55c \ub3c4\ud615)\uc778\uc9c0 \ud310\ubcc4\nif (!Imgproc.isContourConvex(MatOfPoint(*approxCandidate.toArray()))) {\n    throw java.lang.IllegalArgumentException(\"It's not convex\")\n}<\/pre>\n\n\n\n
3. \ud22c\uc2dc \ubcc0\ud658<\/h2>\n\n\n\n
\ud22c\uc2dc\ubcc0\ud658\uc740 OpenCV\uc5d0\uc11c \uc81c\uacf5\ud558\ub294 \ub450 \uac00\uc9c0 \ud568\uc218\uc758 \uc870\ud569\uc744 \ud1b5\ud574 \uc27d\uac8c \uad6c\ud604\ud560 \uc218 \uc788\ub2e4. <\/p>\n\n\n\n