{"id":14062,"date":"2023-02-14T11:08:28","date_gmt":"2023-02-14T03:08:28","guid":{"rendered":"http:\/\/139.9.1.231\/?p=14062"},"modified":"2023-02-14T11:08:29","modified_gmt":"2023-02-14T03:08:29","slug":"sift","status":"publish","type":"post","link":"http:\/\/139.9.1.231\/index.php\/2023\/02\/14\/sift\/","title":{"rendered":"SIFT&#8211;\u5c3a\u5ea6\u4e0d\u53d8\u7279\u5f81\u53d8\u6362"},"content":{"rendered":"\n<p class=\"has-text-align-center has-light-pink-background-color has-background\"><a href=\"https:\/\/docs.opencv.org\/4.1.2\/da\/df5\/tutorial_py_sift_intro.html\"><strong>https:\/\/docs.opencv.org\/4.1.2\/da\/df5\/tutorial_py_sift_intro.html<\/strong><\/a><\/p>\n\n\n\n<p>       SIFT\uff0c\u5373\u5c3a\u5ea6\u4e0d\u53d8\u7279\u5f81\u53d8\u6362\uff08Scale-invariant feature transform\uff0cSIFT\uff09\uff0c\u662f\u7528\u4e8e\u56fe\u50cf\u5904\u7406\u9886\u57df\u7684\u4e00\u79cd\u63cf\u8ff0\u3002\u8fd9\u79cd\u63cf\u8ff0\u5177\u6709\u5c3a\u5ea6\u4e0d\u53d8\u6027\uff0c\u53ef\u5728\u56fe\u50cf\u4e2d\u68c0\u6d4b\u51fa\u5173\u952e\u70b9\uff0c\u662f\u4e00\u79cd\u5c40\u90e8\u7279\u5f81\u63cf\u8ff0\u5b50\u3002<\/p>\n\n\n\n<p>       \u5c3a\u5ea6\u4e0d\u53d8\u7279\u5f81\u53d8\u6362 (Scale-invariant feature transform, SIFT)&nbsp;\u662f\u8ba1\u7b97\u673a\u89c6\u89c9\u4e2d\u4e00\u79cd\u68c0\u6d4b\u3001\u63cf\u8ff0\u548c\u5339\u914d\u56fe\u50cf\u5c40\u90e8\u7279\u5f81\u70b9\u7684\u65b9\u6cd5\uff0c\u901a\u8fc7\u5728\u4e0d\u540c\u7684\u5c3a\u5ea6\u7a7a\u95f4\u4e2d\u68c0\u6d4b\u6781\u503c\u70b9\u6216\u7279\u5f81\u70b9 (Conrner Point, Interest Point) \uff0c\u63d0\u53d6\u51fa\u5176\u4f4d\u7f6e\u3001\u5c3a\u5ea6\u548c\u65cb\u8f6c\u4e0d\u53d8\u91cf\uff0c\u5e76\u751f\u6210\u7279\u5f81\u63cf\u8ff0\u5b50\uff0c\u6700\u540e\u7528\u4e8e\u56fe\u50cf\u7684\u7279\u5f81\u70b9\u5339\u914d\u3002SIFT \u7279\u5f81\u51ed\u501f\u5176\u826f\u597d\u7684\u6027\u80fd\u5e7f\u6cdb\u5e94\u7528\u4e8e\u8fd0\u52a8\u8ddf\u8e2a (Motion tracking) \u3001\u56fe\u50cf\u62fc\u63a5 (Automatic mosaicing) \u30013D \u91cd\u5efa (3D reconstruction) \u3001\u79fb\u52a8\u673a\u5668\u4eba\u5bfc\u822a (Mobile robot navigation) \u4ee5\u53ca\u76ee\u6807\u8bc6\u522b (Object Recognition) \u7b49\u9886\u57df\u3002<\/p>\n\n\n\n<p id=\"sift\u7279\u5f81\u7684\u7279\u70b9\"><strong>SIFT\u7279\u5f81\u7684\u7279\u70b9<\/strong>\uff1a<\/p>\n\n\n\n<p>      SIFT\u662f\u4e00\u79cd\u68c0\u6d4b\u3001\u63cf\u8ff0\u3001\u5339\u914d\u56fe\u50cf\u5c40\u90e8\u7279\u5f81\u70b9\u7684\u7b97\u6cd5\uff0c\u901a\u8fc7\u5728\u5c3a\u5ea6\u7a7a\u95f4\u4e2d\u68c0\u6d4b\u6781\u503c\u70b9\uff0c\u63d0\u53d6\u4f4d\u7f6e\u3001\u5c3a\u5ea6\u3001\u65cb\u8f6c\u4e0d\u53d8\u91cf\uff0c\u5e76\u62bd\u8c61\u6210\u7279\u5f81\u5411\u91cf\u52a0\u4ee5\u63cf\u8ff0\uff0c\u6700\u540e\u7528\u4e8e\u56fe\u50cf\u7279\u5f81\u70b9\u7684\u5339\u914d\u3002SIFT\u7279\u5f81\u5bf9\u7070\u5ea6\u3001\u5bf9\u6bd4\u5ea6\u53d8\u6362\u3001\u65cb\u8f6c\u3001\u5c3a\u5ea6\u7f29\u653e\u7b49\u4fdd\u6301\u4e0d\u53d8\u6027\uff0c\u5bf9\u89c6\u89d2\u53d8\u5316\u3001\u4eff\u5c04\u53d8\u5316\u3001\u566a\u58f0\u4e5f\u5177\u6709\u4e00\u5b9a\u7684\u9c81\u68d2\u6027\u3002\u4f46\u5176\u5b9e\u65f6\u6027\u4e0d\u9ad8\uff0c\u5bf9\u8fb9\u7f18\u5149\u6ed1\u7684\u76ee\u6807\u65e0\u6cd5\u51c6\u786e\u63d0\u53d6\u7279\u5f81\u70b9\u3002<\/p>\n\n\n\n<p>S<strong>IFT\u7b97\u6cd5\u4e3b\u8981\u5305\u62ec\u56db\u4e2a\u6b65\u9aa4\u3002<\/strong><\/p>\n\n\n\n<h4 id=\"1\">1. \u5c3a\u5ea6\u7a7a\u95f4\u6781\u503c\u68c0\u6d4b<a href=\"https:\/\/woshicver.com\/Sixth\/5_4_SIFT%EF%BC%88%E5%B0%BA%E5%BA%A6%E4%B8%8D%E5%8F%98%E7%89%B9%E5%BE%81%E5%8F%98%E6%8D%A2%EF%BC%89%E7%AE%80%E4%BB%8B\/#1\"><\/a><\/h4>\n\n\n\n<p>\u4ece\u4e0a\u56fe\u53ef\u4ee5\u660e\u663e\u770b\u51fa\uff0c\u6211\u4eec\u4e0d\u80fd\u4f7f\u7528\u76f8\u540c\u7684\u7a97\u53e3\u6765\u68c0\u6d4b\u5177\u6709\u4e0d\u540c\u6bd4\u4f8b\u7684\u5173\u952e\u70b9\u3002\u5373\u4fbf\u5c0f\u62d0\u89d2\u53ef\u4ee5\u3002\u4f46\u662f\u8981\u68c0\u6d4b\u66f4\u5927\u7684\u62d0\u89d2\uff0c\u6211\u4eec\u5c06\u9700\u8981\u66f4\u5927\u7684\u7a97\u53e3\u3002\u4e3a\u6b64\uff0c\u4f7f\u7528\u4e86\u6bd4\u4f8b\u7a7a\u95f4\u6ee4\u6ce2\u3002\u5728\u5176\u4e2d\uff0c\u627e\u5230\u5177\u6709\u5404\u79cd\u03c3\u503c\u7684\u56fe\u50cf\u7684\u9ad8\u65af\u62c9\u666e\u62c9\u65af\u7b97\u5b50\u3002LoG\u7528\u4f5c\u6591\u70b9\u68c0\u6d4b\u5668\uff0c\u53ef\u68c0\u6d4b\u7531\u4e8e\u03c3\u7684\u53d8\u5316\u800c\u5bfc\u81f4\u7684\u5404\u79cd\u5927\u5c0f\u7684\u6591\u70b9\u3002\u7b80\u800c\u8a00\u4e4b\uff0c\u03c3\u7528\u4f5c\u7f29\u653e\u53c2\u6570\u3002\u4f8b\u5982\uff0c\u5728\u4e0a\u56fe\u4e2d\uff0c\u4f4e\u03c3\u7684\u9ad8\u65af\u6838\u5bf9\u4e8e\u8f83\u5c0f\u7684\u62d0\u89d2\u7ed9\u51fa\u8f83\u9ad8\u7684\u503c\uff0c\u800c\u9ad8\u03c3\u7684\u9ad8\u65af\u6838\u5bf9\u4e8e\u8f83\u5927\u7684\u62d0\u89d2\u800c\u8a00\u975e\u5e38\u5408\u9002\u3002\u56e0\u6b64\uff0c\u6211\u4eec\u53ef\u4ee5\u627e\u5230\u6574\u4e2a\u5c3a\u5ea6\u548c\u7a7a\u95f4\u4e0a\u7684\u5c40\u90e8\u6700\u5927\u503c\uff0c\u8fd9\u7ed9\u4e86\u6211\u4eec(x,y,\u03c3)\u503c\u7684\u5217\u8868\uff0c\u8fd9\u610f\u5473\u7740\u5728(x,y\u5728\u03c3\u5c3a\u5ea6\u4e0a\u6709\u4e00\u4e2a\u6f5c\u5728\u7684\u5173\u952e\u70b9\u3002<\/p>\n\n\n\n<p>\u4f46\u662f\u8fd9\u79cdLoG\u4ee3\u4ef7\u6602\u8d35\uff0c\u56e0\u6b64SIFT\u7b97\u6cd5\u4f7f\u7528\u7684\u662f\u9ad8\u65af\u5dee\u503c\uff0c\u5b83\u662fLoG\u7684\u8fd1\u4f3c\u503c\u3002\u9ad8\u65af\u5dee\u662f\u4f5c\u4e3a\u5177\u6709\u4e24\u4e2a\u4e0d\u540c\u03c3\u7684\u56fe\u50cf\u7684\u9ad8\u65af\u6a21\u7cca\u5dee\u800c\u83b7\u5f97\u7684\uff0c\u8bbe\u4e3a\u03c3\u548ck\u03c3\u3002\u6b64\u8fc7\u7a0b\u662f\u9488\u5bf9\u9ad8\u65af\u91d1\u5b57\u5854\u4e2d\u56fe\u50cf\u7684\u4e0d\u540c\u516b\u5ea6\u5b8c\u6210\u7684\u3002\u5982\u4e0b\u56fe\u6240\u793a\uff1a<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img src=\"http:\/\/qiniu.aihubs.net\/sift_dog.jpg\" alt=\"\"\/><\/figure><\/div>\n\n\n\n<p>\u4e00\u65e6\u627e\u5230\u8be5DoG\uff0c\u4fbf\u4f1a\u5728\u56fe\u50cf\u4e0a\u641c\u7d22\u6bd4\u4f8b\u548c\u7a7a\u95f4\u4e0a\u7684\u5c40\u90e8\u6781\u503c\u3002\u4f8b\u5982\uff0c\u5c06\u56fe\u50cf\u4e2d\u7684\u4e00\u4e2a\u50cf\u7d20\u4e0e\u51768\u4e2a\u76f8\u90bb\u50cf\u7d20\u4ee5\u53ca\u4e0b\u4e00\u4e2a\u6bd4\u4f8b\u76849\u4e2a\u50cf\u7d20\u548c\u524d\u4e00\u4e2a\u6bd4\u4f8b\u76849\u4e2a\u50cf\u7d20\u8fdb\u884c\u6bd4\u8f83\u3002\u5982\u679c\u662f\u5c40\u90e8\u6781\u503c\uff0c\u5219\u53ef\u80fd\u662f\u5173\u952e\u70b9\u3002\u4ece\u6839\u672c\u4e0a\u8bf4\uff0c\u5173\u952e\u70b9\u662f\u6700\u597d\u7684\u4ee3\u8868\u3002\u5982\u4e0b\u56fe\u6240\u793a\uff1a<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img src=\"http:\/\/qiniu.aihubs.net\/sift_local_extrema.jpg\" alt=\"\"\/><\/figure><\/div>\n\n\n\n<p>\u5bf9\u4e8e\u4e0d\u540c\u7684\u53c2\u6570\uff0c\u672c\u6587\u7ed9\u51fa\u4e86\u4e00\u4e9b\u7ecf\u9a8c\u6570\u636e\uff0c\u53ef\u4ee5\u6982\u62ec\u4e3a\uff1aoctaves=4\uff0c\u7f29\u653e\u5c3a\u5ea6=5\uff0c\u521d\u59cb\u03c3=1.6\uff0ck=\u221a2\u7b49\u4f5c\u4e3a\u6700\u4f73\u503c\u3002<\/p>\n\n\n\n<h4 id=\"2\">2. \u5173\u952e\u70b9\u5b9a\u4f4d<a href=\"https:\/\/woshicver.com\/Sixth\/5_4_SIFT%EF%BC%88%E5%B0%BA%E5%BA%A6%E4%B8%8D%E5%8F%98%E7%89%B9%E5%BE%81%E5%8F%98%E6%8D%A2%EF%BC%89%E7%AE%80%E4%BB%8B\/#2\"><\/a><\/h4>\n\n\n\n<p>\u4e00\u65e6\u627e\u5230\u6f5c\u5728\u7684\u5173\u952e\u70b9\u4f4d\u7f6e\uff0c\u5c31\u5fc5\u987b\u5bf9\u5176\u8fdb\u884c\u4f18\u5316\u4ee5\u83b7\u53d6\u66f4\u51c6\u786e\u7684\u7ed3\u679c\u3002\u4ed6\u4eec\u4f7f\u7528\u4e86\u6807\u5ea6\u7a7a\u95f4\u7684\u6cf0\u52d2\u7ea7\u6570\u5c55\u5f00\u6765\u83b7\u5f97\u66f4\u7cbe\u786e\u7684\u6781\u503c\u4f4d\u7f6e\uff0c\u5982\u679c\u8be5\u6781\u503c\u5904\u7684\u5f3a\u5ea6\u5c0f\u4e8e\u9608\u503c\uff08\u6839\u636e\u8bba\u6587\u4e3a0.03\uff09\uff0c\u5219\u5c06\u5176\u62d2\u7edd\u3002\u5728OpenCV DoG\u4e2d\uff0c\u6b64\u9608\u503c\u79f0\u4e3a**ContrastThreshold**\uff0c\u5b83\u5bf9\u8fb9\u7f18\u7684\u54cd\u5e94\u8f83\u9ad8\uff0c\u56e0\u6b64\u4e5f\u9700\u8981\u5220\u9664\u8fb9\u7f18\u3002<\/p>\n\n\n\n<p>\u4e3a\u6b64\uff0c\u4f7f\u7528\u7c7b\u4f3c\u4e8e\u54c8\u91cc\u65af\u62d0\u89d2\u68c0\u6d4b\u5668\u7684\u6982\u5ff5\u3002\u4ed6\u4eec\u4f7f\u75282&#215;2\u7684Hessian\u77e9\u9635(H)\u8ba1\u7b97\u4e3b\u66f2\u7387\u3002\u4ece\u54c8\u91cc\u65af\u62d0\u89d2\u68c0\u6d4b\u5668\u6211\u4eec\u77e5\u9053\uff0c\u5bf9\u4e8e\u8fb9\u7f18\uff0c\u4e00\u4e2a\u7279\u5f81\u503c\u5927\u4e8e\u53e6\u4e00\u4e2a\u7279\u5f81\u503c\u3002\u56e0\u6b64\uff0c\u8fd9\u91cc\u4ed6\u4eec\u4f7f\u7528\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u51fd\u6570\u3002<\/p>\n\n\n\n<p>\u5982\u679c\u8be5\u6bd4\u7387\u5927\u4e8e\u4e00\u4e2a\u9608\u503c\uff08\u5728OpenCV\u4e2d\u79f0\u4e3a**edgeThreshold**\uff09\uff0c\u5219\u8be5\u5173\u952e\u70b9\u5c06\u88ab\u4e22\u5f03\u3002\u8bba\u6587\u4e0a\u5199\u7684\u503c\u4e3a10\u3002<\/p>\n\n\n\n<p>\u56e0\u6b64\uff0c\u5b83\u6d88\u9664\u4e86\u4efb\u4f55\u4f4e\u5bf9\u6bd4\u5ea6\u7684\u5173\u952e\u70b9\u548c\u8fb9\u7f18\u5173\u952e\u70b9\uff0c\u5269\u4e0b\u7684\u5c31\u662f\u5f88\u53ef\u80fd\u7684\u76ee\u6807\u70b9\u3002<\/p>\n\n\n\n<h4 id=\"3\">3. \u65b9\u5411\u5206\u914d<a href=\"https:\/\/woshicver.com\/Sixth\/5_4_SIFT%EF%BC%88%E5%B0%BA%E5%BA%A6%E4%B8%8D%E5%8F%98%E7%89%B9%E5%BE%81%E5%8F%98%E6%8D%A2%EF%BC%89%E7%AE%80%E4%BB%8B\/#3\"><\/a><\/h4>\n\n\n\n<p>\u73b0\u5728\uff0c\u5c06\u65b9\u5411\u5206\u914d\u7ed9\u6bcf\u4e2a\u5173\u952e\u70b9\uff0c\u4ee5\u5b9e\u73b0\u56fe\u50cf\u65cb\u8f6c\u7684\u4e0d\u53d8\u6027\u3002\u6839\u636e\u6bd4\u4f8b\u5728\u5173\u952e\u70b9\u4f4d\u7f6e\u9644\u8fd1\u91c7\u53d6\u90bb\u57df\uff0c\u5e76\u5728\u8be5\u533a\u57df\u4e2d\u8ba1\u7b97\u68af\u5ea6\u5927\u5c0f\u548c\u65b9\u5411\u3002\u521b\u5efa\u4e86\u4e00\u4e2a\u5177\u670936\u4e2a\u8986\u76d6360\u5ea6\u7684bin\u7684\u65b9\u5411\u76f4\u65b9\u56fe\uff08\u901a\u8fc7\u68af\u5ea6\u5e45\u5ea6\u548c\u03c3\u7b49\u4e8e\u5173\u952e\u70b9\u6bd4\u4f8b\u76841.5\u7684\u9ad8\u65af\u52a0\u6743\u5706\u7a97\u52a0\u6743\uff09\u3002\u63d0\u53d6\u76f4\u65b9\u56fe\u4e2d\u7684\u6700\u9ad8\u5cf0\uff0c\u5e76\u4e14\u5c06\u5176\u8d85\u8fc780\uff05\u7684\u4efb\u4f55\u5cf0\u4e5f\u89c6\u4e3a\u8ba1\u7b97\u65b9\u5411\u3002\u5b83\u521b\u5efa\u7684\u4f4d\u7f6e\u548c\u6bd4\u4f8b\u76f8\u540c\u4f46\u65b9\u5411\u4e0d\u540c\u7684\u5173\u952e\u70b9\u3002\u5b83\u6709\u52a9\u4e8e\u5339\u914d\u7684\u7a33\u5b9a\u6027\u3002<\/p>\n\n\n\n<h4 id=\"4\">4. \u5173\u952e\u70b9\u63cf\u8ff0<a href=\"https:\/\/woshicver.com\/Sixth\/5_4_SIFT%EF%BC%88%E5%B0%BA%E5%BA%A6%E4%B8%8D%E5%8F%98%E7%89%B9%E5%BE%81%E5%8F%98%E6%8D%A2%EF%BC%89%E7%AE%80%E4%BB%8B\/#4\"><\/a><\/h4>\n\n\n\n<p>\u73b0\u5728\u521b\u5efa\u4e86\u5173\u952e\u70b9\u63cf\u8ff0\u7b26\u3002\u5728\u5173\u952e\u70b9\u5468\u56f4\u91c7\u7528\u4e8616&#215;16\u7684\u90bb\u57df\u3002\u5b83\u5206\u4e3a16\u4e2a4&#215;4\u5927\u5c0f\u7684\u5b50\u5757\u3002\u5bf9\u4e8e\u6bcf\u4e2a\u5b50\u5757\uff0c\u521b\u5efa8 bin\u65b9\u5411\u76f4\u65b9\u56fe\u3002\u56e0\u6b64\u5171\u6709128\u4e2abin\u503c\u53ef\u7528\u3002\u5b83\u88ab\u8868\u793a\u4e3a\u5f62\u6210\u5173\u952e\u70b9\u63cf\u8ff0\u7b26\u7684\u5411\u91cf\u3002\u9664\u6b64\u4e4b\u5916\uff0c\u8fd8\u91c7\u53d6\u4e86\u51e0\u79cd\u63aa\u65bd\u6765\u5b9e\u73b0\u9488\u5bf9\u7167\u660e\u53d8\u5316\uff0c\u65cb\u8f6c\u7b49\u7684\u9c81\u68d2\u6027\u3002<\/p>\n\n\n\n<h4 id=\"5\">5. \u5173\u952e\u70b9\u5339\u914d<a href=\"https:\/\/woshicver.com\/Sixth\/5_4_SIFT%EF%BC%88%E5%B0%BA%E5%BA%A6%E4%B8%8D%E5%8F%98%E7%89%B9%E5%BE%81%E5%8F%98%E6%8D%A2%EF%BC%89%E7%AE%80%E4%BB%8B\/#5\"><\/a><\/h4>\n\n\n\n<p>\u901a\u8fc7\u8bc6\u522b\u4e24\u4e2a\u56fe\u50cf\u7684\u6700\u8fd1\u90bb\uff0c\u53ef\u4ee5\u5339\u914d\u4e24\u4e2a\u56fe\u50cf\u4e4b\u95f4\u7684\u5173\u952e\u70b9\u3002\u4f46\u662f\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u7b2c\u4e8c\u4e2a\u6700\u63a5\u8fd1\u7684\u5339\u914d\u53ef\u80fd\u975e\u5e38\u63a5\u8fd1\u7b2c\u4e00\u4e2a\u3002\u5b83\u53ef\u80fd\u662f\u7531\u4e8e\u566a\u97f3\u6216\u5176\u4ed6\u539f\u56e0\u800c\u53d1\u751f\u7684\u3002\u5728\u90a3\u79cd\u60c5\u51b5\u4e0b\uff0c\u91c7\u7528\u6700\u63a5\u8fd1\u8ddd\u79bb\u4e0e\u7b2c\u4e8c\u6700\u63a5\u8fd1\u8ddd\u79bb\u4e4b\u6bd4\u3002\u5982\u679c\u5927\u4e8e0.8\uff0c\u5c06\u88ab\u62d2\u7edd\u3002\u6839\u636e\u8bba\u6587\uff0c\u5b83\u53ef\u4ee5\u6d88\u9664\u5927\u7ea690\uff05\u7684\u9519\u8bef\u5339\u914d\uff0c\u800c\u4ec5\u4e22\u5f035\uff05\u7684\u6b63\u786e\u5339\u914d\u3002 \u56e0\u6b64\uff0c\u8fd9\u662fSIFT\u7b97\u6cd5\u7684\u603b\u7ed3\u3002\u6709\u5173\u66f4\u591a\u8be6\u7ec6\u4fe1\u606f\u548c\u7406\u89e3\uff0c\u5f3a\u70c8\u5efa\u8bae\u9605\u8bfb\u539f\u59cb\u8bba\u6587\u3002\u8bb0\u4f4f\u4e00\u4ef6\u4e8b\uff0c\u8be5\u7b97\u6cd5\u5df2\u7533\u8bf7\u4e13\u5229\u3002\u6240\u4ee5\u8fd9\u4e2a\u7b97\u6cd5\u5305\u542b\u5728opencv contrib repo\u4e2d.<\/p>\n\n\n\n<h3 id=\"opencvsift\">OpenCV\u4e2d\u7684SIFT<a href=\"https:\/\/woshicver.com\/Sixth\/5_4_SIFT%EF%BC%88%E5%B0%BA%E5%BA%A6%E4%B8%8D%E5%8F%98%E7%89%B9%E5%BE%81%E5%8F%98%E6%8D%A2%EF%BC%89%E7%AE%80%E4%BB%8B\/#opencvsift\"><\/a><\/h3>\n\n\n\n<p>\u73b0\u5728\uff0c\u8ba9\u6211\u4eec\u6765\u770b\u4e00\u4e0bOpenCV\u4e2d\u53ef\u7528\u7684SIFT\u529f\u80fd\u3002\u8ba9\u6211\u4eec\u4ece\u5173\u952e\u70b9\u68c0\u6d4b\u5f00\u59cb\u5e76\u8fdb\u884c\u7ed8\u5236\u3002\u9996\u5148\uff0c\u6211\u4eec\u5fc5\u987b\u6784\u9020\u4e00\u4e2aSIFT\u5bf9\u8c61\u3002\u6211\u4eec\u53ef\u4ee5\u5c06\u4e0d\u540c\u7684\u53c2\u6570\u4f20\u9012\u7ed9\u5b83\uff0c\u8fd9\u4e9b\u53c2\u6570\u662f\u53ef\u9009\u7684\uff0c\u5b83\u4eec\u5728docs\u4e2d\u5df2\u5f97\u5230\u5f88\u597d\u7684\u89e3\u91ca\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import numpy as np\nimport cv2 as cv\nimg = cv.imread('home.jpg')\ngray= cv.cvtColor(img,cv.COLOR_BGR2GRAY)\nsift = cv.xfeatures2d.SIFT_create()\nkp = sift.detect(gray,None)\nimg=cv.drawKeypoints(gray,kp,img)\ncv.imwrite('sift_keypoints.jpg',img)\n<\/code><\/pre>\n\n\n\n<p><strong>sift.detect<\/strong>()\u51fd\u6570\u5728\u56fe\u50cf\u4e2d\u627e\u5230\u5173\u952e\u70b9\u3002\u5982\u679c\u53ea\u60f3\u641c\u7d22\u56fe\u50cf\u7684\u4e00\u90e8\u5206\uff0c\u5219\u53ef\u4ee5\u901a\u8fc7\u63a9\u7801\u3002\u6bcf\u4e2a\u5173\u952e\u70b9\u662f\u4e00\u4e2a\u7279\u6b8a\u7684\u7ed3\u6784\uff0c\u5177\u6709\u8bb8\u591a\u5c5e\u6027\uff0c\u4f8b\u5982\u5176(x\uff0cy)\u5750\u6807\uff0c\u6709\u610f\u4e49\u7684\u90bb\u57df\u7684\u5927\u5c0f\uff0c\u6307\u5b9a\u5176\u65b9\u5411\u7684\u89d2\u5ea6\uff0c\u6307\u5b9a\u5173\u952e\u70b9\u5f3a\u5ea6\u7684\u54cd\u5e94\u7b49\u3002<\/p>\n\n\n\n<p>OpenCV\u8fd8\u63d0\u4f9b**cv.drawKeyPoints**()\u51fd\u6570\uff0c\u8be5\u51fd\u6570\u5728\u5173\u952e\u70b9\u7684\u4f4d\u7f6e\u7ed8\u5236\u5c0f\u5706\u5708\u3002 \u5982\u679c\u5c06\u6807\u5fd7**cv.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS**\u4f20\u9012\u7ed9\u5b83\uff0c\u5b83\u5c06\u7ed8\u5236\u4e00\u4e2a\u5177\u6709\u5173\u952e\u70b9\u5927\u5c0f\u7684\u5706\uff0c\u751a\u81f3\u4f1a\u663e\u793a\u5176\u65b9\u5411\u3002 \u8bf7\u53c2\u89c1\u4ee5\u4e0b\u793a\u4f8b\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>img=cv.drawKeypoints(gray,kp,img,flags=cv.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv.imwrite('sift_keypoints.jpg',img)\n<\/code><\/pre>\n\n\n\n<p>\u67e5\u770b\u4e0b\u9762\u7684\u7ed3\u679c\uff1a&nbsp;<img alt=\"\" src=\"http:\/\/qiniu.aihubs.net\/sift_keypoints.jpg\"><\/p>\n\n\n\n<p>\u73b0\u5728\u8981\u8ba1\u7b97\u63cf\u8ff0\u7b26\uff0cOpenCV\u63d0\u4f9b\u4e86\u4e24\u79cd\u65b9\u6cd5\u3002 1. \u7531\u4e8e\u5df2\u7ecf\u627e\u5230\u5173\u952e\u70b9\uff0c\u56e0\u6b64\u53ef\u4ee5\u8c03\u7528**sift.compute**()\uff0c\u8be5\u51fd\u6570\u6839\u636e\u6211\u4eec\u627e\u5230\u7684\u5173\u952e\u70b9\u6765\u8ba1\u7b97\u63cf\u8ff0\u7b26\u3002\u4f8b\u5982\uff1a<code>kp\uff0cdes = sift.compute(gray\uff0ckp)<\/code>&nbsp;2. \u5982\u679c\u627e\u4e0d\u5230\u5173\u952e\u70b9\uff0c\u5219\u53ef\u4ee5\u4f7f\u7528**sift.detectAndCompute**()\u51fd\u6570\u5728\u5355\u6b65\u9aa4\u4e2d\u76f4\u63a5\u627e\u5230\u5173\u952e\u70b9\u548c\u63cf\u8ff0\u7b26\u3002<\/p>\n\n\n\n<p>\u6211\u4eec\u5c06\u770b\u5230\u7b2c\u4e8c\u79cd\u65b9\u6cd5\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sift = cv.xfeatures2d.SIFT_create() \nkp, des = sift.detectAndCompute(gray,None)\n<\/code><\/pre>\n\n\n\n<p>\u8fd9\u91cc\u7684kp\u5c06\u662f\u4e00\u4e2a\u5173\u952e\u70b9\u5217\u8868\uff0c\u800cdes\u662f\u4e00\u4e2a\u5f62\u72b6\u4e3aNumberofKeypoints\u00d7128\u7684\u6570\u5b57\u6570\u7ec4\u3002<\/p>\n\n\n\n<p>\u8fd9\u6837\u6211\u4eec\u5f97\u5230\u4e86\u5173\u952e\u70b9\uff0c\u63cf\u8ff0\u7b26\u7b49\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>https:\/\/docs.opencv.org\/4.1.2\/da\/df5\/tutorial_py_sift_i &hellip; <a href=\"http:\/\/139.9.1.231\/index.php\/2023\/02\/14\/sift\/\" class=\"more-link\">\u7ee7\u7eed\u9605\u8bfb<span class=\"screen-reader-text\">SIFT&#8211;\u5c3a\u5ea6\u4e0d\u53d8\u7279\u5f81\u53d8\u6362<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[33],"tags":[],"_links":{"self":[{"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/posts\/14062"}],"collection":[{"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/comments?post=14062"}],"version-history":[{"count":28,"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/posts\/14062\/revisions"}],"predecessor-version":[{"id":14126,"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/posts\/14062\/revisions\/14126"}],"wp:attachment":[{"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/media?parent=14062"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/categories?post=14062"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/139.9.1.231\/index.php\/wp-json\/wp\/v2\/tags?post=14062"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}