{"id":1233,"date":"2021-07-21T12:05:23","date_gmt":"2021-07-21T04:05:23","guid":{"rendered":"http:\/\/zerobox.org\/notes\/?p=1233"},"modified":"2021-07-21T12:05:30","modified_gmt":"2021-07-21T04:05:30","slug":"ffmpeg%e5%85%a5%e9%97%a8%e7%af%87-%e6%bb%a4%e9%95%9c%e7%9a%84%e5%9f%ba%e6%9c%ac%e4%bd%bf%e7%94%a8","status":"publish","type":"post","link":"http:\/\/zerobox.org\/notes\/1233.html","title":{"rendered":"ffmpeg\u5165\u95e8\u7bc7-\u6ee4\u955c\u7684\u57fa\u672c\u4f7f\u7528"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\">\u6ee4\u955c<\/h3>\n\n\n\n<p>\u4ec0\u4e48\u662f\u6ee4\u955c\uff1f<a href=\"https:\/\/baike.baidu.com\/item\/%E6%BB%A4%E9%95%9C\/354809\" target=\"_blank\" rel=\"noreferrer noopener\">\u767e\u5ea6\u767e\u79d1<\/a>\u4ecb\u7ecd\u8bf4\u201c\u6ee4\u955c\u4e3b\u8981\u662f\u7528\u6765\u5b9e\u73b0\u56fe\u50cf\u7684\u5404\u79cd\u7279\u6b8a\u6548\u679c&#8230;&#8230;\u201d\u3002<\/p>\n\n\n\n<p>\u6211\u4eec\u6700\u65e9\u5728<a href=\"http:\/\/www.manks.top\/ffmpeg-transcode.html\" target=\"_blank\" rel=\"noreferrer noopener\">ffmpeg\u662f\u5982\u4f55\u8f6c\u7801<\/a>\u7684\u4e00\u6587\u4e2d\u4e86\u89e3\u8fc7\u6ee4\u955c\uff0c\u6765\u56de\u987e\u4e0b\u5f53\u65f6\u7684\u8f6c\u7801\u6d41\u7a0b\u56fe\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"http:\/\/static.manks.top\/uploads\/20210619\/ab3c06901d-ffmpeg-transcode.png\"><img decoding=\"async\" src=\"http:\/\/static.manks.top\/uploads\/20210619\/ab3c06901d-ffmpeg-transcode.png\" alt=\"ab3c06901d-ffmpeg-transcode.png\"\/><\/a><\/figure>\n\n\n\n<p>\u4ece\u56fe\u4e2d\u53ef\u4ee5\u770b\u5230\u6ee4\u955c\u524d\u540e\u753b\u7684\u662f\u865a\u7ebf\uff0c\u8868\u793a\u53ef\u6709\u53ef\u65e0\uff0c\u5728\u672f\u8bed\u4e2d\uff0c\u6ee4\u955c\u6307\u7684\u662f\u5728\u7f16\u7801\u4e4b\u524d\u9488\u5bf9\u89e3\u7801\u5668\u89e3\u7801\u51fa\u6765\u7684\u539f\u59cb\u6570\u636e\uff08\u5373\u97f3\u89c6\u9891\u5e27\uff09\u8fdb\u884c\u5904\u7406\u7684\u52a8\u4f5c\uff0c\u6211\u4eec\u8fd8\u53ef\u4ee5\u79f0\u5b83\u4e3a\u8fc7\u6ee4\u5668\u3002<\/p>\n\n\n\n<p>ffmpeg\u5185\u7f6e\u4e86\u5927\u6982\u8fd1400\u79cd\u6ee4\u955c\uff0c\u6211\u4eec\u53ef\u4ee5\u7528 ffmpeg -filters \u547d\u4ee4\u67e5\u770b\u6240\u6709\u7684\u6ee4\u955c\uff0c\u4e5f\u53ef\u4ee5\u7528\u547d\u4ee4 ffmpeg -h filter=xxx \u6216\u8005\u67e5\u770b<a href=\"http:\/\/ffmpeg.org\/ffmpeg-filters.html\" target=\"_blank\" rel=\"noreferrer noopener\">\u5b98\u65b9\u6587\u6863<\/a>\u4e86\u89e3\u6bcf\u4e00\u79cd\u6ee4\u955c\u3002<\/p>\n\n\n\n<p>\u5b9e\u9645\u5728\u5927\u90e8\u5206\u97f3\u89c6\u9891\u7684\u5904\u7406\u8fc7\u7a0b\u4e2d\u90fd\u79bb\u4e0d\u5f00\u6ee4\u955c\uff0c\u6240\u4ee5\u4f60\u5e94\u8be5\u80fd\u660e\u767d\u5176\u91cd\u8981\u6027\u3002<\/p>\n\n\n\n<p>\u591a\u4e2a\u6ee4\u955c\u53ef\u4ee5\u7ed3\u5408\u5728\u4e00\u8d77\u4f7f\u7528\u5f62\u6210\u6ee4\u955c\u94fe\u6216\u8005\u6ee4\u955c\u56fe\uff0c\u5728\u6bcf\u4e00\u4e2a\u6ee4\u955c\u4e2d\uff0c\u4e0d\u4ec5\u53ef\u4ee5\u5bf9\u8f93\u5165\u6e90\u8fdb\u884c\u5904\u7406\uff0cA\u6ee4\u955c\u5904\u7406\u597d\u7684\u7ed3\u679c\u8fd8\u53ef\u4ee5\u4f5c\u4e3aB\u6ee4\u955c\u7684\u8f93\u5165\u53c2\u6570\uff0c\u901a\u8fc7B\u6ee4\u955c\u7ee7\u7eed\u5904\u7406\u3002<\/p>\n\n\n\n<p>\u9488\u5bf9\u6ee4\u955c\u7684\u5904\u7406\uff0cffmpeg\u63d0\u4f9b\u4e86\u4e24\u79cd\u5904\u7406\u65b9\u5f0f\uff0c\u7b80\u5355\u6ee4\u955c\u548c\u590d\u6742\u6ee4\u955c\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u7b80\u5355\u6ee4\u955c<\/h4>\n\n\n\n<p>\u7b80\u5355\u6ee4\u955c\u6307\u7684\u662f\u53ea\u6709\u4e00\u4e2a\u8f93\u5165\u548c\u8f93\u51fa\uff0c\u800c\u4e14\u4fdd\u8bc1\u8f93\u5165\u548c\u8f93\u51fa\u7684\u6d41\u7c7b\u578b\u76f8\u540c\u3002<\/p>\n\n\n\n<p>\u6bd4\u5982\u6211\u4eec\u5728\u4e0a\u7bc7\u6587\u7ae0<a href=\"http:\/\/www.manks.top\/ffmpeg-stream-selection-map.html\" target=\"_blank\" rel=\"noreferrer noopener\">\u6d41\u7684\u64cd\u4f5c\uff08\u4e8c\uff09\u5982\u4f55\u9009\u62e9\u6d41\uff1f<\/a>\u672b\u5c3e\u63d0\u5230\u7684\u628a\u539f\u89c6\u9891 r3.mp4 \u7b49\u6bd4\u4f8b\u7f29\u653e\u4e00\u500d<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -i r3.mp4 -vf scale=272:480 -y filter.mp4\n<\/pre>\n\n\n\n<p>-vf \u662f -filter:v \u7684\u7b80\u5199\uff0c\u7c7b\u4f3c\u7684\u6211\u4eec\u8fd8\u53ef\u4ee5\u4f7f\u7528 -filter:a \u6216\u8005 -af \u9488\u5bf9\u97f3\u9891\u6d41\u505a\u5904\u7406\u3002<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>-filter\u7684\u8bed\u6cd5\u89c4\u5219\uff1a-filter[:stream_specifier] filtergraph (<em>output,per-stream<\/em>)<br>stream_specifier\u6d41\u7684\u7c7b\u578b\u6211\u4eec\u4e00\u822c\u7528a\u8868\u793a\u97f3\u9891\uff0cv\u8868\u793a\u89c6\u9891\uff0cfiltergraph\u8868\u793a\u5177\u4f53\u7684\u6ee4\u955c\uff0c\u8fd9\u91cc\u7528\u7684\u662f<a href=\"https:\/\/ffmpeg.org\/ffmpeg-filters.html#scale\" target=\"_blank\" rel=\"noreferrer noopener\">scale\u6ee4\u955c<\/a>\u3002<\/p><\/blockquote>\n\n\n\n<p>scale\u6ee4\u955c\u7528\u4e8e\u8c03\u6574\u89c6\u9891\u7684\u5927\u5c0f\uff0c\u6bd4\u5982\u7b49\u6bd4\u4f8b\u7f29\u653e\u3001\u7b49\u6bd4\u4f8b\u653e\u5927\uff0c\u4e0d\u505a\u7b49\u6bd4\u4f8b\u64cd\u4f5c\u8f93\u51fa\u5c31\u53d8\u5f62\u4e86\uff0c\u53d8\u5f62\u7ed3\u679c\u6211\u4eec\u4e00\u822c\u4e0d\u8003\u8651\u3002<\/p>\n\n\n\n<p>\u56e0\u4e3a\u6211\u4eec\u77e5\u9053\u539f\u89c6\u9891 r1ori.mp4 \u7684\u5206\u8fa8\u7387\u662f 544&#215;960\uff0c\u6240\u4ee5\u7b49\u6bd4\u4f8b\u7f29\u653e\u4e00\u500d\uff0c\u4e0a\u9762\u7684\u547d\u4ee4\u76f4\u63a5\u6307\u5b9a\u4e86 272&#215;480\uff0cscale\u6ee4\u955c\u81ea\u5e26\u5f88\u591a\u53c2\u6570\uff0c\u6211\u4eec\u4ecb\u7ecd\u51e0\u4e2a\u5e38\u7528\u7684\u3002<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>in_w in_h \u6216\u8005 iw ih \u8868\u793a\u8f93\u5165\u89c6\u9891\u7684\u5bbd\u9ad8<br>out_w out_h \u6216\u8005 ow oh \u8868\u793a\u8f93\u51fa\u89c6\u9891\u7684\u5bbd\u9ad8<\/p><\/blockquote>\n\n\n\n<p>\u5f53\u7136\u4e0d\u4e00\u5b9a\u662f\u89c6\u9891\uff0c\u8f93\u5165\u8f93\u51fa\u4e5f\u53ef\u4ee5\u662f\u56fe\u7247\u3002<\/p>\n\n\n\n<p>\u6240\u4ee5\u539f\u89c6\u9891\u7f29\u653e\u4e00\u500d\u6211\u4eec\u8fd8\u53ef\u4ee5\u8fd9\u6837\u5199\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -i r3.mp4 -vf scale=iw\/2:ih\/2 -y filter.mp4\n<\/pre>\n\n\n\n<p>\u95ee\u9898\u4e00\uff1a\u5982\u679c\u6211\u4eec\u8981\u628a\u539f\u89c6\u9891\u7684\u5bbd\u5ea6\u8c03\u6574\u4e3a300\u4e14\u4fdd\u6301\u539f\u5206\u8fa8\u7387\uff0c\u600e\u4e48\u529e\uff1f<\/p>\n\n\n\n<p>\u5217\u4e00\u4e2a\u65b9\u7a0b 544\/960 = 300\/x \uff0cx=300&#215;960\/540\uff0c\u5f88\u9ebb\u70e6\uff0c\u7ed3\u679c\u8fd8\u4e0d\u4e00\u5b9a\u80fd\u6574\u9664\uff0c\u4e3a\u6b64\u6211\u4eec\u53ef\u4ee5\u76f4\u63a5\u6307\u5b9a\u9ad8\u5ea6\u7b49\u4e8e-1\uff0c\u5b83\u4f1a\u81ea\u52a8\u505a\u7b49\u6bd4\u4f8b\u5904\u7406\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -i r1ori.mp4 -vf scale=300:-1 -y filter.mp4\n<\/pre>\n\n\n\n<p>\u7ed3\u679c\u53d1\u73b0\u8f6c\u7801\u5931\u8d25\u4e86\uff0c\u63d0\u793a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">[libx264 @ 0x7ff509053a00] height not divisible by 2 (300x529) \nError initializing output stream 0:0 -- \nError while opening encoder for output stream #0:0 - \nmaybe incorrect parameters such as bit_rate, rate, width or height [aac @ 0x7ff50904e200] \nQavg: 28010.410 [aac @ 0x7ff50904e200] 2 frames left in the queue on closing\n<\/pre>\n\n\n\n<p>\u63d0\u793a\u6211\u4eec height not divisible by 2 (300&#215;529)\u5373\u9ad8\u5ea6529\u4e0d\u80fd\u88ab2\u6574\u9664\u3002\u8fd9\u662f\u56e0\u4e3a\u4e00\u4e9b\u7f16\u89e3\u7801\u5668\u8981\u6c42\u5f88\u591a\u89c6\u9891\u7684\u5bbd\u9ad8\u5fc5\u987b\u662fn\u7684\u500d\u6570\uff08\u8fd9\u91ccn\u662f2\uff09\uff0c\u6240\u4ee5\u6211\u4eec\u5199\u811a\u672c\u5904\u7406\u89c6\u9891\u6216\u8005\u56fe\u7247\u5bbd\u9ad8\u7684\u65f6\u5019\uff0c\u5207\u8bb0\u4e0d\u8981\u4f7f\u7528-1\uff0c\u6b63\u786e\u7684\u7528\u6cd5\u662f\u4f7f\u7528-2\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -i r1ori.mp4 -vf scale=300:-2 -y filter.mp4 \u8f93\u51fa\u7ed3\u679c\u89c6\u9891\u7684\u5206\u8fa8\u7387\u662f 300 \u00d7 530\n<\/pre>\n\n\n\n<p>\u95ee\u9898\u4e8c\uff1a\u8001\u677f\u4e3a\u4e86\u5201\u96be\u4f60\uff0c\u63d0\u51fa\u4e86\u4e00\u4e2a\u65b0\u7684\u8981\u6c42\uff1a\u201c\u6211\u60f3\u8981\u6240\u6709\u8f93\u51fa\u89c6\u9891\u7684\u5206\u8fa8\u7387\u662f 300&#215;500\u4e14\u4e0d\u80fd\u53d8\u5f62\u201d\uff0c\u600e\u4e48\u529e\uff1f<\/p>\n\n\n\n<p>\u6211\u4eec\u77e5\u90533:5\u7684\u5bbd\u9ad8\u6bd4\u662f\u5f88\u5c11\u89c1\u7684\uff0c\u73b0\u5728\u5e38\u89c1\u7684\u5206\u8fa8\u7387\u662f16:9\u30014:3\uff0c\u4e5f\u5c31\u662f\u8bf4\u539f\u89c6\u9891\u6211\u4eec\u5fc5\u987b\u8981\u7ecf\u8fc7\u4e00\u756a\u5904\u7406\u624d\u53ef\u4ee5\u6ee1\u8db3\u8001\u677f\u7684\u53d8\u6001\u9700\u6c42\u3002<\/p>\n\n\n\n<p>\u9488\u5bf9\u539f\u89c6\u9891 r1ori.mp4\uff0c\u5982\u679c\u4fdd\u8bc1\u5bbd\u5ea6\u662f300\uff0c\u7b49\u6bd4\u4f8b\u7f29\u653e\u540e\u9ad8\u5ea6\u662f530\uff0c\u5f3a\u5236\u8bbe\u7f6e\u9ad8\u5ea6\u4e3a500\u5c31\u4f1a\u53d8\u5f62\uff0c\u4e5f\u5c31\u662f\u8bf4\u6211\u4eec\u53ea\u80fd\u8ba9\u9ad8\u5ea6\u7b49\u4e8e500\uff0c\u5c3d\u91cf\u7f29\u5c0f\u5bbd\u5ea6\u8bd5\u8bd5\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -i r1ori.mp4 -vf scale=-2:500 -y filter.mp4 \u8f93\u51fa\u7684\u7ed3\u679c\u89c6\u9891\u7684\u5206\u8fa8\u7387\u662f284x500\n<\/pre>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"http:\/\/static.manks.top\/uploads\/20210711\/0b3ef811e3-scale.png\"><img decoding=\"async\" src=\"http:\/\/static.manks.top\/uploads\/20210711\/0b3ef811e3-scale.png\" alt=\"0b3ef811e3-scale.png\"\/><\/a><\/figure>\n\n\n\n<p>\u5982\u4e0a\u56fe\uff0c\u84dd\u8272\u6846\u8868\u793a\u89c6\u9891\u7684\u771f\u5b9e\u5bbd\u9ad8\uff0c\u7ea2\u8272\u6846\u8868\u793a\u76ee\u6807\u5bbd\u9ad8\uff0c\u6709\u4e9b\u50cfhtml\u4e2d\u7684css\u4e00\u6837\uff0c\u53ef\u4ee5\u7ed9\u7a7a\u51fa\u6765\u7684\u90e8\u5206\u586b\u5145\u989c\u8272\u5373\u5185\u8fb9\u8ddd\u4e0d\u5c31\u53ef\u4ee5\u4e86\uff1f<\/p>\n\n\n\n<p>\u67e5\u9605\u4e86\u6587\u6863\u6211\u4eec\u53d1\u73b0<a href=\"https:\/\/ffmpeg.org\/ffmpeg-filters.html#pad-1\" target=\"_blank\" rel=\"noreferrer noopener\">pad\u6ee4\u955c<\/a>\u53ef\u4ee5\u89e3\u51b3\u6211\u4eec\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>pad\u6ee4\u955c\u7684\u8bed\u6cd5\u89c4\u5219\uff1a-pad=width[:height[:x[:y[:color]]]]<\/p><\/blockquote>\n\n\n\n<pre class=\"wp-block-preformatted\">1\u3001ffmpeg -i r1ori.mp4 -vf \"scale=-2:500,pad=300:500:(300-iw)\/2:0\" -y filter2.mp4 \n2\u3001ffmpeg -i r1ori.mp4 -vf scale=-2:500,pad=300:500:-1:0 -y filter.mp4 \n3\u3001ffmpeg -i r1ori.mp4 -vf scale=-2:500,pad=300:500:-1:0:black -y filter.mp4 \n4\u3001ffmpeg -i r1ori.mp4 -vf \"scale=-2:500,pad=300:ih:(ow-iw)\/2:0:green\" -y filter.mp4\n<\/pre>\n\n\n\n<p>\u4e0a\u9762\u63d0\u4f9b4\u4e2d\u5199\u6cd5\uff0c\u6211\u4eec\u4ee5\u65b9\u6cd54\u505a\u4e2a\u7b80\u5355\u4ecb\u7ecd\u3002<\/p>\n\n\n\n<p>scale=-2:500\uff0c\u6307\u539f\u89c6\u9891\u6309\u7167\u7b49\u6bd4\u4f8b\u7f29\u653e\uff0c\u9ad8\u5ea6\u7b49\u4e8e500\uff0c\u5c31\u662f\u4e0a\u9762\u5927\u5bb6\u770b\u5230\u7684284&#215;500\u3002<\/p>\n\n\n\n<p>pad=300:ih:(ow-iw)\/2:0:green\uff0c300:ih\u5373300:500\u5c31\u662f\u7ea2\u8272\u6846\u7684\u5bbd\u9ad8(ow-iw)\/2\uff0c\u6307\u7684\u662f\u7ea2\u8272\u6846\u548c\u84dd\u8272\u6846\u5dee\u503c\u7684\u4e00\u534a\uff0c\u5373\u4e24\u8fb9\u5404\u9700\u8981\u586b\u5145\u7684\u8303\u56f4\uff1b\u6700\u540e\u4e00\u4e2a\u53c2\u6570\u8868\u793a\u9700\u8981\u586b\u5145\u7684\u989c\u8272\uff0c\u9ed8\u8ba4\u662f\u9ed1\u8272 black\uff0c\u4e3a\u4e86\u8c03\u8bd5\u65b9\u4fbf\u6211\u4eec\u628a\u989c\u8272\u8bbe\u4e3agreen\u3002<\/p>\n\n\n\n<p>\u73b0\u5728\u6211\u4eec\u4fdd\u8bc1\u4e86\u5f53\u524d\u89c6\u9891\u4e00\u5b9a\u4f1a\u6309\u7167300&#215;500\u7684\u6bd4\u4f8b\u8f93\u51fa\u4e14\u4e0d\u4f1a\u53d8\u5f62\uff0c\u4f46\u662f\u8bf7\u6ce8\u610f\u8001\u677f\u8bf4\u7684\u201c\u6240\u6709\u8f93\u51fa\u89c6\u9891\u201d\uff0c\u4e5f\u5c31\u662f\u8bf4\u8f93\u5165\u89c6\u9891\u7684\u5206\u8fa8\u7387\u53ef\u80fd\u662f200&#215;300\u3001544&#215;960\u3001500&#215;400\u3001200&#215;800\u7b49\u7b49\u5404\u79cd\u6bd4\u4f8b\u90fd\u8981\u4fdd\u8bc1\u6309\u7167300&#215;500\u8f93\u51fa\uff0c\u5f88\u663e\u7136\uff0c\u4e0a\u9762\u7684\u5199\u6cd5\u4e0d\u5b8c\u5168\u901a\u7528\uff0c\u600e\u4e48\u529e\uff1f<\/p>\n\n\n\n<p>\u73b0\u5728\u6211\u4eec\u5df2\u77e5\u539f\u8f93\u5165\u89c6\u9891\u7684\u5bbd\u9ad8\u548c\u60f3\u8981\u7684\u5bbd\u9ad8\uff0c\u9488\u5bf9\u8fd9\u79cd\u60c5\u51b5\uff0c\u6211\u4eec\u5236\u5b9a\u4e00\u5957\u5904\u7406\u89c4\u5219\u5373\u53ef\u89e3\u51b3\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u5bbd\u9ad8\u90fd\u504f\u5c0f\uff0c\u4e0d\u62c9\u4f38\uff0c\u4e0d\u7f29\u653e<\/li><li>\u5bbd\u9ad8\u90fd\u504f\u5927\uff0c\u7b49\u6bd4\u4f8b\u7f29\u5c0f\uff0c\u4ee5\u9ad8\u5ea6\u4e3a\u51c6<\/li><li>\u5bbd\u8d85\u51fa\u8303\u56f4\uff0c\u7b49\u6bd4\u4f8b\u7f29\u5c0f\uff0c\u4ee5\u5bbd\u4e3a\u51c6<\/li><li>\u9ad8\u8d85\u51fa\u8303\u56f4\uff0c\u7b49\u6bd4\u4f8b\u7f29\u5c0f\uff0c\u4ee5\u9ad8\u4e3a\u51c6<\/li><\/ol>\n\n\n\n<p>\u5728\u5b9e\u9645\u7684\u5f00\u53d1\u8fc7\u7a0b\u4e2d\uff0c\u6211\u4eec\u8981\u8ddf\u4ee3\u7801\u6253\u4ea4\u9053\uff0c\u5e73\u65f6\u5728\u547d\u4ee4\u884c\u4e2d\u7684\u5b9e\u73b0\u90fd\u662f\u7ec3\u4e60\uff0c\u6240\u4ee5\u57fa\u4e8e\u8be5\u89c4\u5219\uff0c\u6211\u4eec\u6709\u4e86\u4e0b\u9762\u4e00\u6bb5\u4ee3\u7801<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">&lt;?php\ndeclare(strict_types=1);\n\nclass CalculatorService\n{\n    \/**\n     * \u7528\u6237\u89c6\u9891\u5206\u8fa8\u7387\u8f6c\u6362\n     * \u89c4\u5219\uff1a\n     *  \u5bbd\u9ad8\u90fd\u504f\u5c0f\uff0c\u4e0d\u62c9\u4f38\uff0c\u4e0d\u7f29\u653e\n     *  \u5bbd\u9ad8\u90fd\u504f\u5927\uff0c\u7b49\u6bd4\u4f8b\u7f29\u5c0f\uff0c\u4ee5\u9ad8\u5ea6\u4e3a\u51c6\n     *  \u5bbd\u8d85\u51fa\u8303\u56f4\uff0c\u7b49\u6bd4\u4f8b\u7f29\u5c0f\uff0c\u4ee5\u5bbd\u4e3a\u51c6\n     *  \u9ad8\u8d85\u51fa\u8303\u56f4\uff0c\u7b49\u6bd4\u4f8b\u7f29\u5c0f\uff0c\u4ee5\u9ad8\u4e3a\u51c6\n     * @param int $inputWidth \u8f93\u5165\u89c6\u9891\u7684\u5bbd\u5ea6\n     * @param int $inputHeight \u8f93\u5165\u89c6\u9891\u7684\u9ad8\u5ea6\n     * @param int $outWidth \u8f93\u51fa\u89c6\u9891\u7684\u5bbd\u9ad8\n     * @param int $outHeight \u8f93\u51fa\u89c6\u9891\u7684\u9ad8\u5ea6\n     * @return string scale\n     *\/\n    public function getSize(int $inputWidth, int $inputHeight, int $outWidth, int $outHeight): string\n    {\n        $scale = \"\";\n        if ($inputWidth &lt;= $outWidth &amp;&amp; $inputHeight &lt;= $outHeight) {\n            $scale = \"scale={$inputWidth}:{$inputHeight},pad={$outWidth}:{$outHeight}:-1:-1:green\";\n        } elseif (($inputWidth &gt; $outWidth &amp;&amp; $inputHeight &gt; $outHeight)\n            || ($inputHeight &gt; $outHeight)\n        ) {\n            $scale = \"scale=-2:{$outHeight},pad={$outWidth}:{$outHeight}:-1:0:green\";\n        } elseif ($inputWidth &gt; $outWidth) {\n            $scale = \"scale={$outWidth}:-2,pad={$outWidth}:{$outHeight}:0:-1:green\";\n        }\n\n        return $scale;\n    }\n}\n\n$calculatorService = new CalculatorService();\nvar_dump($calculatorService-&gt;getSize(200, 300, 300, 500));\nvar_dump($calculatorService-&gt;getSize(544, 960, 300, 500));\nvar_dump($calculatorService-&gt;getSize(500, 400, 300, 500));\nvar_dump($calculatorService-&gt;getSize(200, 600, 300, 500));\n\n\/\/ \u7ed3\u679c\nstring(37) \"scale=200:300,pad=300:500:-1:-1:green\"\nstring(35) \"scale=-2:500,pad=300:500:-1:0:green\"\nstring(35) \"scale=300:-2,pad=300:500:0:-1:green\"\nstring(35) \"scale=-2:500,pad=300:500:-1:0:green\"\n<\/pre>\n\n\n\n<p>\u4e3a\u4e86\u65b9\u4fbf\u7406\u89e3\uff0c\u5927\u5bb6\u53ef\u4ee5\u53c2\u8003\u4e0b\u9762\u7684\u56fe\u4e00\u4e00\u5bf9\u5e94\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"http:\/\/static.manks.top\/uploads\/20210711\/93492a2e96-scale2.png\"><img decoding=\"async\" src=\"http:\/\/static.manks.top\/uploads\/20210711\/93492a2e96-scale2.png\" alt=\"93492a2e96-scale2.png\"\/><\/a><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">\u590d\u6742\u6ee4\u955c<\/h4>\n\n\n\n<p>\u76f8\u5bf9\u4e8e\u7b80\u5355\u6ee4\u955c\uff0c\u590d\u6742\u6ee4\u955c\u662f\u53ef\u4ee5\u5904\u7406\u4efb\u610f\u6570\u91cf\u8f93\u5165\u548c\u8f93\u51fa\u6548\u679c\u7684\u6ee4\u955c\u56fe\uff0c\u5b83\u51e0\u4e4e\u65e0\u6240\u4e0d\u80fd\u3002<\/p>\n\n\n\n<p>\u590d\u6742\u6ee4\u955c\u7528\u547d\u4ee4 -filter_complex \u8868\u793a\uff0c\u5b83\u8fd8\u6709\u4e00\u4e2a\u522b\u540d -lavfi\u3002<\/p>\n\n\n\n<p>\u4e0a\u7bc7\u6587\u7ae0\u4ecb\u7ecd\u5230\u6d41\u548c\u6ee4\u955c\u7ed3\u5408\u662f\u4e00\u79cd\u6700\u91cd\u8981\u3001\u6700\u5e38\u7528\u7684\u65b9\u6cd5\u3002\u4f9d\u7136\u662f\u5c06\u8f93\u5165\u89c6\u9891 r3.mp4 \u7b49\u6bd4\u4f8b\u7f29\u653e\u4e00\u500d\uff0c\u6211\u4eec\u4ee5\u624b\u52a8\u9009\u62e9\u6d41\u7684\u65b9\u5f0f\u4e3a\u4f8b\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -i r3.mp4 -filter_complex \"[0]scale=272:480[out]\" -map 0:a -map \"[out]\" -y filter.mp4 <\/pre>\n\n\n\n<p>\u7b80\u5355\u5206\u6790\u5982\u4e0b\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u547d\u4ee4 &#8220;[0]scale=272:480[out]&#8221; \u4e2d\u7684[0]\u8868\u793a\u7b2c\u4e00\u4e2a\u8f93\u5165\u7684\u89c6\u9891\uff0c\u56e0\u4e3a\u8981\u5bf9\u89c6\u9891\u505a\u5904\u7406\uff0c\u6240\u4ee5\u4e5f\u53ef\u4ee5\u7528[0:v]\u8868\u793a\uff0c\u5982\u679c\u8981\u5bf9\u97f3\u9891\u5355\u72ec\u5904\u7406\uff0c\u5c31\u9700\u8981\u7528 [0:a] \u4e86\uff1b<\/li><li>[0] \u7ed3\u5408scale\u6ee4\u955c\uff0c\u8868\u793a\u7684\u5c31\u662f\u628a\u7b2c\u4e00\u4e2a\u8f93\u5165\u7684\u89c6\u9891\u4f5c\u4e3ascale\u6ee4\u955c\u7684\u53c2\u6570\u8f93\u5165\uff1b<\/li><li>[out] \u4e2d\u62ec\u53f7\u662f\u5fc5\u987b\u8981\u7684\uff0cout\u662f\u81ea\u5b9a\u4e49\u7684\u4e00\u4e2a\u522b\u540d\uff0c\u7ed3\u5408scale\u6ee4\u955c\uff0c\u8868\u793a\u7684\u662f\u628ascale\u6ee4\u955c\u8f93\u51fa\u7684\u7ed3\u679c\u547d\u540d\u4e3a[out]\uff0c\u4f46\u5e76\u975e\u662f\u6700\u7ec8\u8f93\u51fa\u7684\u7ed3\u679c\uff0c\u53ea\u80fd\u4f5c\u4e3a\u4e2d\u95f4\u8fc7\u7a0b\u8f93\u51fa\u7684\u4e00\u4e2a\u7ed3\u679c\uff1b<\/li><li>-map &#8220;[out]&#8221; \u5c31\u662f\u76f4\u63a5\u9009\u62e9[out] \u6d41\u4f5c\u4e3a\u8f93\u51fa<\/li><\/ol>\n\n\n\n<p>\u6211\u4eec\u8bf4\u8fc7\uff0c\u4e00\u4e2a\u6ee4\u955c\u7684\u8f93\u51fa\u4f5c\u4e3a\u53e6\u4e00\u4e2a\u6ee4\u955c\u7684\u8f93\u5165\uff0c\u8fd9\u6837\u5c31\u6781\u5927\u7684\u907f\u514d\u4e86\u5199\u591a\u6761\u547d\u4ee4\u53cd\u590d\u7f16\u89e3\u7801\u64cd\u4f5c\uff0c\u6211\u4eec\u7684\u539f\u5219\u53ea\u6709\u4e00\u4e2a\uff0c\u80fd\u7528\u4e00\u6761\u547d\u4ee4\u5904\u7406\u7684\u7edd\u4e0d\u7528\u4e24\u6761\u547d\u4ee4\u3002<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>\u6709\u635f\u7f16\u89e3\u7801\u5668\u53cd\u590d\u7f16\u89e3\u7801\u64cd\u4f5c\u4f1a\u964d\u4f4e\u539f\u89c6\u9891\u8d28\u91cf\u3002<\/p><\/blockquote>\n\n\n\n<p>\u6bd4\u5982\u73b0\u5728\u8981\u628a\u539f\u89c6\u9891 r1ori.mp4 \u7684\u4e2d\u95f4\u90e8\u5206\u88c1\u526a\u51fa\u6765\uff0c\u4f46\u4ecd\u4fdd\u6301\u539f\u89c6\u9891\u7684\u5206\u8fa8\u7387544&#215;960\uff0c\u5982\u4f55\u505a\u5462\uff1f<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -i r1ori.mp4 -filter_complex \"nullsrc=s=544x960[background]; \\\ncrop=iw:(ih\/2 - 110):0:250[middle]; \\\n[background][middle]overlay=shortest=1:x=(main<em>_w-overlay_<\/em>w)\/2:y=(main<em>_h-overlay_<\/em>h)\/2[out]\" \\\n-map \"[out]\" \n-map 0:a \n-movflags +faststart \n-y fc.mp4<\/pre>\n\n\n\n<p>\u8fd9\u4e2a\u547d\u4ee4\u5c31\u663e\u5f97\u7a0d\u5fae\u957f\u4e86\u4e00\u4e9b\uff0c\u5728\u8fd9\u6761\u547d\u4ee4\u4e2d\u4f7f\u7528\u4e86<a href=\"https:\/\/ffmpeg.org\/ffmpeg-filters.html#allrgb_002c-allyuv_002c-color_002c-haldclutsrc_002c-nullsrc_002c-pal75bars_002c-pal100bars_002c-rgbtestsrc_002c-smptebars_002c-smptehdbars_002c-testsrc_002c-testsrc2_002c-yuvtestsrc\" target=\"_blank\" rel=\"noreferrer noopener\">nullsrc<\/a>\u3001<a href=\"https:\/\/ffmpeg.org\/ffmpeg-filters.html#crop\" target=\"_blank\" rel=\"noreferrer noopener\">crop<\/a>\u3001<a href=\"https:\/\/ffmpeg.org\/ffmpeg-filters.html#overlay-1\" target=\"_blank\" rel=\"noreferrer noopener\">overlay<\/a>\u4e09\u79cd\u5e38\u89c1\u6ee4\u955c\u3002<\/p>\n\n\n\n<p>nullsrc\u6ee4\u955c\u7528\u4e8e\u521b\u5efa\u4e00\u4e2a\u7a7a\u7684\u89c6\u9891\uff0c\u7b80\u5355\u7684\u8bf4\u5c31\u662f\u4e00\u4e2a\u7a7a\u7684\u753b\u5e03\u6216\u8005\u8bf4\u662f\u7eff\u5e03\uff0c\u56e0\u4e3a\u9ed8\u8ba4\u521b\u5efa\u7684\u989c\u8272\u662f\u7eff\u8272\u7684\u3002s\u7528\u4e8e\u6307\u5b9a\u753b\u5e03\u7684\u5927\u5c0f\uff0c\u9ed8\u8ba4\u662f320&#215;240\uff0c\u8fd9\u91cc\u8868\u793a\u6211\u4eec\u521b\u5efa\u4e00\u4e2a544&#215;960\u7684\u753b\u5e03\uff0c\u5e76\u547d\u540d\u4e3abackground\uff1b<\/p>\n\n\n\n<p>\u5173\u4e8enullsrc\u8fd8\u6709\u5f88\u591a\u79cd\u4e0d\u540c\u7684\u7528\u6237\uff0c\u6bd4\u5982\u4f7f\u7528nullsrc\u548cCIQRCodeGenerator\u521b\u5efa\u4e00\u4e2a\u201c\u767d\u72fc\u6808\u201d\u9996\u9875\u7684\u4e8c\u7ef4\u7801<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ffmpeg -f lavfi -i nullsrc=s=200x200,coreimage=filter=CIQRCodeGenerator@inputMessage=\\ \nhttp\\\\\\\\\\:\/\/manks.top\/@inputCorrectionLevel=H -frames:v 1 manks.png<\/pre>\n\n\n\n<p>crop\u6ee4\u955c\u7528\u4e8e\u88c1\u526a\u89c6\u9891\uff0c\u4e5f\u5c31\u662f\u8bf4\u89c6\u9891\u7684\u4efb\u610f\u533a\u57df\u4efb\u610f\u5927\u5c0f\uff0c\u6211\u4eec\u90fd\u53ef\u4ee5\u88c1\u526a\u51fa\u6765\u3002crop=iw:(ih\/2 &#8211; 110):0:250[middle]; \u8fd9\u91cc\u6211\u4eec\u88c1\u526a\u539f\u89c6\u9891\u7684\u4e2d\u95f4\u90e8\u5206\u5e76\u547d\u540d\u4e3amiddle\uff1b<\/p>\n\n\n\n<p>overlay\u6ee4\u955c\u8868\u793a\u4e24\u4e2a\u89c6\u9891\u76f8\u4e92\u53e0\u52a0\uff0cshortest\u5b98\u7f51\u662f\u8fd9\u4e48\u4ecb\u7ecd\u7684\uff1a\u201cIf set to 1, force the output to terminate when the shortest input terminates. Default value is 0.\u201d\uff0c\u56e0\u4e3a\u6211\u4eec\u4f7f\u7528nullsrc\u521b\u5efa\u4e86\u4e00\u4e2a\u6ca1\u6709\u65f6\u95f4\u8f74\u7684\u753b\u5e03\uff0c\u6240\u4ee5\u8fd9\u91cc\u9700\u8981\u4ee5middle\u7684\u89c6\u9891\u65f6\u95f4\u4e3a\u6700\u7ec8\u65f6\u95f4\uff0c\u6545\u8bbe\u7f6e\u4e3a1\u3002main_w\u548cmain_h\u8868\u793a\u4e3b\u89c6\u9891\u7684\u5bbd\u9ad8\uff0coverlay_w\u548coverlay_h\u8868\u793a\u53e0\u52a0\u89c6\u9891\u7684\u5bbd\u9ad8\u3002\u5982\u679c\u8981\u628aA\u89c6\u9891\u53e0\u52a0\u5230B\u89c6\u9891\u4e0a\uff0c\u5219main_w\u548cmain_h\u8868\u793aB\u89c6\u9891\u7684\u5bbd\u9ad8\uff0coverlay_w\u548coverlay_h\u8868\u793aA\u89c6\u9891\u7684\u5bbd\u9ad8\u3002\u5408\u8d77\u6765\u4fbf\u662f\u628amiddle\u53e0\u52a0\u5230background\u4e4b\u4e0a\u4e14\u7f6e\u4e8ebackground\u7684\u4e2d\u95f4\uff08\u76f8\u5f53\u4e8e\u6709\u4e2a\u53e0\u52a0\u5c42\u7684\u6982\u5ff5\uff09\uff1b<\/p>\n\n\n\n<p>\u6700\u540e\u4e00\u4e2a\u53c2\u6570\u662f-movflags\uff0c\u5b83\u8ddfmp4\u7684\u5143\u6570\u636e\u6709\u5173\uff0c\u8bbe\u4e3afaststart\u8868\u793a\u4f1a\u5c06moov\u79fb\u52a8\u5230mdat\u7684\u524d\u9762\uff0c\u5728\u7ebf\u64ad\u653e\u7684\u65f6\u5019\u4f1a\u7a0d\u5fae\u5feb\u4e00\u4e9b\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p>\u6765\u6e90\uff1ahttp:\/\/www.manks.top\/ffmpeg-basic-use-of-filters.html<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6ee4\u955c \u4ec0\u4e48\u662f\u6ee4\u955c\uff1f\u767e\u5ea6\u767e\u79d1\u4ecb\u7ecd\u8bf4\u201c\u6ee4\u955c\u4e3b\u8981\u662f\u7528\u6765\u5b9e\u73b0\u56fe\u50cf\u7684\u5404\u79cd\u7279\u6b8a\u6548\u679c&#038;#823 &hellip;<\/p>\n<p class=\"read-more\"><a href=\"http:\/\/zerobox.org\/notes\/1233.html\">\u7ee7\u7eed\u9605\u8bfb &raquo;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[270,269,271],"class_list":["post-1233","post","type-post","status-publish","format-standard","hentry","tag-ffmpeg","tag-269","tag-271"],"views":293,"_links":{"self":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/posts\/1233","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/comments?post=1233"}],"version-history":[{"count":0,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/posts\/1233\/revisions"}],"wp:attachment":[{"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/media?parent=1233"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/categories?post=1233"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/zerobox.org\/notes\/wp-json\/wp\/v2\/tags?post=1233"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}