{"id":3084,"date":"2024-01-12T14:12:38","date_gmt":"2024-01-12T06:12:38","guid":{"rendered":"https:\/\/www.xianwaizhiyin.net\/?p=3084"},"modified":"2024-01-12T18:42:37","modified_gmt":"2024-01-12T10:42:37","slug":"h264probe","status":"publish","type":"post","link":"https:\/\/www.xianwaizhiyin.net\/?p=3084","title":{"rendered":"h264_probe\u63a2\u6d4bh264\u683c\u5f0f\u2014FFmpeg\u6e90\u7801\u5206\u6790"},"content":{"rendered":"\n<p><span style=\"color: gray;font-size: 14px;\">\u4f5c\u8005\uff1a\u7f57\u4e0a\u6587\uff0c\u5fae\u4fe1\uff1aLoken1\uff0c\u516c\u4f17\u53f7\uff1aFFmpeg\u5f26\u5916\u4e4b\u97f3<\/span><\/p>\n\n\n\n<p>\u672c\u6587\u4f7f\u7528\u7684\u547d\u4ee4\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >ffmpeg -i juren-30s.h264 out.flv -y\n<\/code><\/pre>\n\n\n\n<p>\u8bf7\u53c2\u8003\u300a<a href=\"https:\/\/ffmpeg.xianwaizhiyin.net\/debug-ffmpeg\/ubuntu18-clion.html\" target=\"_blank\" rel=\"noreferrer noopener\">\u7528Ubuntu18\u4e0eclion\u8c03\u8bd5FFmpeg<\/a>\u300b\u642d\u5efa\u597d\u8c03\u8bd5\u73af\u5883\uff0c<code class=\"prettyprint\" >juren-30s.h264<\/code>&nbsp;\u5728&nbsp;<a href=\"https:\/\/github.com\/lokenetwork\/FFmpeg-Principle\/tree\/main\/videos\" target=\"_blank\" rel=\"noreferrer noopener\">GitHub<\/a>&nbsp;\u91cc\u9762\u6709\u7684\uff0c\u8bf7\u81ea\u884c\u4e0b\u8f7d\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>\u51e0\u4e4e\u6bcf\u4e00\u4e2a&nbsp;<code class=\"prettyprint\" >Demuxer<\/code>&nbsp;\u90fd\u6709\u81ea\u5df1\u7684&nbsp;<code>probe<\/code>&nbsp;\u63a2\u6d4b\u51fd\u6570\u7684\uff0c\u63a2\u6d4b\u51fd\u6570\u88ab\u8c03\u7528\u7684\u4f4d\u7f6e\uff0c\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/demuxer\/h264_probe\/1-1.jpg\" alt=\"1-1\"\/><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><code class=\"prettyprint\" >h264_probe()<\/code>&nbsp;\u51fd\u6570\u7684\u5185\u90e8\u6d41\u7a0b\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/demuxer\/h264_probe\/1-2.jpg\" alt=\"1-2\"\/><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><code class=\"prettyprint\" >h264_probe()<\/code>&nbsp;\u51fd\u6570\u7684\u91cd\u70b9\u5982\u4e0b\uff1a<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"1\uff0c\u627e\u5230\u6bcf\u4e2a-nalu-\u7684\u5f00\u5934\">1\uff0c\u627e\u5230\u6bcf\u4e2a NALU \u7684\u5f00\u5934<\/h4>\n\n\n\n<p>Annex B \u683c\u5f0f\u7684\u5404\u4e2a NALU \u4e4b\u95f4\u662f\u7528 Start Codes (<code class=\"prettyprint\" >0x000001<\/code>) \u8ddf \u586b\u5145\u5b57\u7b26 0 \u6765\u5206\u9694\u3002\u6240\u4ee5\u5728&nbsp;<code>for<\/code>&nbsp;\u5faa\u73af\u91cc\u9762\uff0c<strong>\u9700\u8981\u627e\u5230 \u8d77\u59cb\u7801\uff0c\u540c\u65f6\u8fd8\u8981\u5904\u7406\u586b\u5145\u5b57\u7b26 0<\/strong>\uff0c\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/demuxer\/h264_probe\/1-3.png\" alt=\"1-3\"\/><\/figure>\n\n\n\n<p>\u8fd9\u6bb5\u4ee3\u7801\u662f\u6bd4\u8f83\u590d\u6742\u7684\uff0c\u6211\u4e5f\u770b\u4e86\u633a\u4e45\u7684\uff0c\u9996\u5148\u53d8\u91cf&nbsp;<code class=\"prettyprint\" >code<\/code>&nbsp;\u9ed8\u8ba4\u662f -1\uff0c\u6ce8\u610f\uff0c\u4ed6\u662f<strong>\u65e0\u7b26\u53f7\u7684 32\u4f4d\u7c7b\u578b\u7684<\/strong>\u3002\u6240\u4ee5&nbsp;<code>code<\/code>&nbsp;\u7684\u4e8c\u8fdb\u5236\u8868\u793a\u662f<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >code = -1 = 0b1111 1111 1111 1111 1111 1111 1111 1111\n<\/code><\/pre>\n\n\n\n<p>code \u5185\u5b58\u7684 32 \u4f4d\u5168\u90e8\u90fd\u662f 1\uff0c\u7136\u540e\u4ed6\u5faa\u73af\u91cc\uff0c\u6bcf\u6b21\u90fd\u628a&nbsp;<code class=\"prettyprint\" >code<\/code>&nbsp;\u53f3\u79fb 8 \u4f4d\uff0c\u8fd0\u7b97\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >0b1111 1111 1111 1111 1111 1111 1111 1111 &lt;&lt; 8 = 0b1111 1111 1111 1111 1111 1111 0000 0000\n<\/code><\/pre>\n\n\n\n<p>\u53ef\u4ee5\u770b\u5230\uff0c\u6700\u540e8\u4f4d\u53d8\u6210\u4e86 0\uff0c\u6240\u4ee5\u7a7a\u51fa\u6765\u4e868\u4f4d\u7684\u7a7a\u95f4\u3002\u8fd9 8 \u4f4d\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u5176\u5b9e\u662f\u7ed9&nbsp;<code class=\"prettyprint\" >p-&gt;buf[i]<\/code>&nbsp;\u7528\u7684\uff0c<code>p-&gt;buf[i]<\/code>&nbsp;\u5360 8 \u4f4d\u3002<\/p>\n\n\n\n<p><strong>\u6240\u4ee5&nbsp;<code class=\"prettyprint\" >(code &lt;&lt; 8) + p-&gt;buf[i]<\/code>&nbsp;\u8fd9\u53e5\u4ee3\u7801\u7684\u542b\u4e49\uff0c\u5c31\u662f\u6bcf\u6b21\u90fd\u8bfb\u53d6\u4e00\u4e2a\u5b57\u8282\uff0c\u7136\u540e\u653e\u5728\u672b\u5c3e\u3002<\/strong><\/p>\n\n\n\n<p>\u7136\u540e\uff0c\u4e0b\u9762\u7684\u8fd9\u53e5\u4ee3\u7801\u4e5f\u662f\u4e0d\u592a\u5bb9\u6613\u7406\u89e3\u7684\uff0c\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >if ((code &amp; 0xffffff00) == 0x100)\n<\/code><\/pre>\n\n\n\n<p>\u56e0\u4e3a \u8d77\u59cb\u7801 \u524d\u9762\u53ef\u80fd\u4f1a\u586b\u5145\u591a\u4e2a 0 \u6765<strong>\u5bf9\u9f50\u6570\u636e\u957f\u5ea6<\/strong>\uff0c\u6240\u4ee5\u6211\u4eec\u9700\u8981\u5904\u7406\u586b\u5145\u5b57\u7b26\u3002\u5176\u5b9e\u8fd9\u6bb5\u4ee3\u7801\u662f\u5904\u7406\u4e86\u586b\u5145\u5b57\u7b26 0 \u7684\u3002\u4f60\u9700\u8981\u628a&nbsp;<code class=\"prettyprint\" >0xffffff00<\/code>&nbsp;\u8ddf&nbsp;<code>0x100<\/code>&nbsp;\u8f6c\u6210\u4e8c\u8fdb\u5236\u624d\u80fd\u770b\u61c2\u4ed6\u7684\u4ee3\u7801\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >0xffffff00 = 0b1111 1111 1111 1111 1111 1111 0000 0000\n0x100 = 0b0000 0000 0000 0000 0000 0001 0000 0000\n<\/code><\/pre>\n\n\n\n<p>\u56e0\u6b64\u00a0<code class=\"prettyprint\" >code &amp; 0xffffff00<\/code>\u00a0\u64cd\u4f5c\uff0c\u4f1a\u6d88\u9664\u6700\u540e 8 \u4f4d\uff0c\u4f46\u662f\uff0c\u4f46\u662f\uff0c\u524d\u9762\u7684 24 \u4f4d\u662f\u4fdd\u7559\u7684\uff0c\u6240\u4ee5\u4e0a\u4e00\u6b21\u8bfb\u53d6\u51fa\u6765\u7684\u90a3\u4e2a\u5b57\u8282\u662f\u4fdd\u7559\u4e0b\u6765\u7684\uff0c\u6ce8\u610f\uff0c\u662f\u4e0a\u4e00\u6b21\u3002<\/p>\n\n\n\n<p>\u56e0\u6b64\u5f53\u8bfb\u53d6\u5230 67 \u8fd9\u4e2a\u5b57\u8282\u7684\u65f6\u5019\uff0c\u5982\u4e0b\uff0c67 \u5c31\u4f1a\u88ab\u653e\u5230\u53d8\u91cf&nbsp;<code class=\"prettyprint\" >code<\/code>&nbsp;\u7684\u540e 8 \u4f4d\uff0c\u8fd9\u65f6\u5019&nbsp;<code>code<\/code>&nbsp;\u5c31\u7b49\u4e8e\u4e0b\u9762\u7684\u503c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >code        = 0b0000 0000 0000 0000 0000 0001 0110 0111\n<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/demuxer\/h264_probe\/1-4.png\" alt=\"1-4\"\/><\/figure>\n\n\n\n<p>\u56e0\u6b64&nbsp;<code class=\"prettyprint\" >if ((code &amp; 0xffffff00) == 0x100)<\/code>&nbsp;\u5c31\u4f1a\u6210\u7acb\uff0c\u5c31\u7b97\u627e\u5230 NALU \u4e86\u3002\u8bfb\u8005\u53ef\u4ee5\u81ea\u884c\u8c03\u8bd5\u4e00\u4e0b\uff0c\u5c31\u5f88\u5bb9\u6613\u770b\u61c2\u8fd9\u6bb5\u4ee3\u7801\u3002<\/p>\n\n\n\n<p><strong>\u5c0f\u603b\u7ed3\uff1a\u8fd9\u6bb5\u4ee3\u7801\u7684\u903b\u8f91\u5176\u5b9e\u5c31\u662f\u8981\u627e\u5230\u4e00\u5b57\u8282\u7684&nbsp;<code class=\"prettyprint\" >0x1<\/code>\uff0c\u7136\u540e\u524d\u9762\u7684 2 \u4e2a\u5b57\u8282\u5fc5\u987b\u5168\u662f 0 \uff0c\u8fd9\u5c31\u662f\u627e\u5230 NALU \u7684\u903b\u8f91\u3002<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"2\uff0c\u5224\u65ad-nalu-\u662f\u5426\u4ea7\u751f\u4e86\u6bd4\u7279\u9519\u8bef\">2\uff0c\u5224\u65ad NALU \u662f\u5426\u4ea7\u751f\u4e86\u6bd4\u7279\u9519\u8bef<\/h4>\n\n\n\n<p>\u4e4b\u524d\u5728\u300a<a href=\"https:\/\/ffmpeg-vip.xianwaizhiyin.net\/demuxer\/h264_annexb.html\" target=\"_blank\" rel=\"noreferrer noopener\">H.264 Annex B\u683c\u5f0f\u5206\u6790<\/a>\u300b\u8bb2\u8fc7\uff0cNALU \u5934\u90e8\u7684\u7b2c\u4e00\u4f4d\u5982\u679c\u662f 1\uff0c\u4e5f\u5c31\u662f&nbsp;<code class=\"prettyprint\" >forbidden_bit<\/code>&nbsp;\u5b57\u6bb5\u5982\u679c\u7b49\u4e8e 1\uff0c\u5c31\u4ee3\u8868\u8fd9\u4e2a NALU \u53d1\u751f\u4e86\u6bd4\u7279\u9519\u8bef\uff0c\u6240\u4ee5\u4e0b\u9762\u8fd9\u53e5\u4ee3\u7801\u5c31\u662f\u5224\u65ad \u6bd4\u7279\u9519\u8bef\u7684\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >if (code &amp; 0x80) \/\/ forbidden_bit\n    return 0;\n<\/code><\/pre>\n\n\n\n<p><code class=\"prettyprint\" >0x80<\/code> \u8f6c\u6210 \u4e8c\u8fdb\u5236\u8868\u8fbe\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >0x80 = 0b1000 0000\n<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"3\uff0crefzero-\u5224\u65ad-nalu-\u662f\u5426\u7b26\u5408h264\u6807\u51c6\">3\uff0c<code class=\"prettyprint\" >ref_zero<\/code>&nbsp;\u5224\u65ad NALU \u662f\u5426\u7b26\u5408H.264\u6807\u51c6<\/h4>\n\n\n\n<p><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/demuxer\/h264_probe\/1-5.png\" alt=\"1-5\"\/><\/figure>\n\n\n\n<p>\u4e0a\u56fe\u4e2d\u7684 \u53d8\u91cf&nbsp;<code class=\"prettyprint\" >ref_idc<\/code>&nbsp;\u5c31\u662f&nbsp;<strong>StreamAnalyzer<\/strong>&nbsp;\u8f6f\u4ef6\u91cc\u9762\u5c55\u793a\u7684&nbsp;<code>nal_ref_idc<\/code>&nbsp;\uff0c\u53d8\u91cf&nbsp;<code>type<\/code>&nbsp;\u5c31\u662f&nbsp;<code>nal_unit_type<\/code>\uff0c\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/demuxer\/h264_probe\/1-5-2.png\" alt=\"1-5-2\"\/><\/figure>\n\n\n\n<p>\u90a3&nbsp;<code class=\"prettyprint\" >ref_zero[]<\/code>&nbsp;\u8fd9\u4e2a\u53d8\u91cf\u662f\u5e72\u4ec0\u4e48\u7684\u5462\uff1f\u6211\u4e5f\u4e0d\u77e5\u9053\u4ed6\u4e3a\u4ec0\u4e48\u8d77\u540d\u5b57\u53eb&nbsp;<code>zero<\/code>\uff0c\u4f46\u662f\u8fd9\u4e2a\u547d\u540d\u8fd8\u662f\u633a\u597d\u7684\u3002\u53ea\u662f\u6211\u4e0d\u77e5\u9053\u600e\u4e48\u628a&nbsp;<code>zero<\/code>&nbsp;\u7ffb\u8bd1\u6210\u4e2d\u6587\u8868\u8fbe\u7ed9\u5927\u5bb6\u542c\u3002<\/p>\n\n\n\n<p><code class=\"prettyprint\" >ref_zero[]<\/code>&nbsp;\u5176\u5b9e\u662f\u4e00\u4e2a\u6620\u5c04\u8868\uff0c\u8fd9\u4e2a\u6620\u5c04\u8868\u662f\u7528\u6765\u5224\u65ad NALU \u7684\u6570\u636e\u662f\u5426\u7b26\u5408H264\u6807\u51c6\u3002\u8fd9\u4e2a\u5728\u300a\u65b0\u4e00\u4ee3\u89c6\u9891\u538b\u7f29\u7f16\u7801\u6807\u51c6\u300b\u4e00\u4e66\u6709\u4ecb\u7ecd\uff0c\u5982\u4e0b\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><code class=\"prettyprint\" >al_ref_idc<\/code>&nbsp;\u6307\u7684\u662f\u5f53\u524d NAL \u7684\u4f18\u5148\u7ea7\u3002\u53d6\u503c\u8303\u56f4\u4e3a 0\uff5e3\uff0c\u503c\u8d8a\u9ad8\uff0c\u8868\u793a\u5f53\u524d NAL \u8d8a\u91cd\u8981\uff0c\u8d8a\u9700\u8981\u4f18\u5148\u53d7\u5230\u4fdd\u62a4\u3002H.264 \u89c4\u5b9a\u5982\u679c\u5f53\u524d NAL \u662f\u4e00\u4e2a\u5e8f\u5217\u53c2\u6570\u96c6\uff0c\u6216\u4e00\u4e2a\u56fe\u50cf\u53c2\u6570\u96c6\uff0c\u5c5e\u4e8e\u53c2\u8003\u56fe\u50cf\u7684\u7247\u6216\u7247\u5206\u533a\u7b49\u91cd\u8981\u7684\u6570\u636e\u5355\u4f4d\u65f6\uff0c<strong>\u672c\u53e5\u6cd5\u5143\u7d20\u5fc5\u987b\u5927\u4e8e0<\/strong>\u3002\u4f46\u5728\u5927\u4e8e 0 \u65f6\u5177\u4f53\u8be5\u53d6\u4f55\u503c\uff0c\u5e76\u6ca1\u6709\u8fdb\u4e00\u6b65\u7684\u89c4\u5b9a\uff0c\u901a\u4fe1\u53cc\u65b9\u53ef\u4ee5\u7075\u6d3b\u5730\u5236\u5b9a\u7b56\u7565\u3002<strong>\u5f53&nbsp;<code>nal_unit_type<\/code>&nbsp;\u7b49\u4e8e 5 \u65f6\uff0c<code>nal_ref_idc<\/code>&nbsp;\u5927\u4e8e 0\u3002\u5f53&nbsp;<code>nal_unit_type<\/code>&nbsp;\u7b49\u4e8e 6\u30019\u300110\u300111 \u621612 \u65f6\uff0c<code>nal_ref_idc<\/code>&nbsp;\u7b49\u4e8e 0\u3002<\/strong><\/p>\n<\/blockquote>\n\n\n\n<p>\u4e0a\u9762\u8fd9\u6bb5\u8bdd\uff0c\u5176\u5b9e\u4e5f\u662f H.264 \u6807\u51c6\u7684\u5185\u5bb9\uff0c\u4ed6\u9650\u5236\u4e86\u5728\u4ec0\u4e48\u573a\u666f\u4e0b\uff0c<code class=\"prettyprint\" >nal_ref_idc<\/code>&nbsp;\u7684\u53d6\u503c\u8303\u56f4\uff0c<strong>\u5fc5\u987b\u8fd9\u4e48\u505a<\/strong>\u3002<\/p>\n\n\n\n<p>\u6211\u4eec\u57fa\u4e8e\u8fd9\u4e2a\u903b\u8f91\u6765\u7406\u89e3 FFmpeg \u7684\u4ee3\u7801\u5c31\u597d\u7406\u89e3\u5f88\u591a\u4e86\uff0c\u4f8b\u5982\u4e0b\u9762\u8fd9\u53e5\u4ee3\u7801\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >if (ref_zero&#091;type] == 1 &amp;&amp; ref_idc)\n   return 0;\n<\/code><\/pre>\n\n\n\n<p><code class=\"prettyprint\" >ref_zero[]<\/code>&nbsp;\u6570\u7ec4\u91cc\uff0c\u54ea\u4e9b&nbsp;<code>type<\/code>&nbsp;\u7b49\u4e8e 1 \uff1f\u5c31\u662f 6\u30019\u300110\u300111 \u621612\u3002\u5728\u8fd9\u4e9b\u573a\u666f\u4e0b\uff0c\u5982\u679c&nbsp;<code>ref_idc<\/code>&nbsp;\u4e0d\u7b49\u4e8e 0\uff0c\u4e5f\u5c31\u662f\u6709\u503c\uff0c\u8fd9\u4e2a NALU \u5c31\u4e0d\u7b26\u5408\u6807\u51c6\uff0c\u5c31\u76f4\u63a5\u8fd4\u56de 0\uff0c0 \u662f\u6700\u4f4e\u7684\u6253\u5206\u3002<\/p>\n\n\n\n<p>\u5176\u4ed6\u7684\u5224\u65ad\u4e5f\u662f\u7c7b\u4f3c\u7684\u539f\u7406\uff0c\u8bfb\u8005\u81ea\u884c\u63a8\u5bfc\u4e00\u756a\u5c31\u53ef\u4ee5\u4e86\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"4\uff0c\u7edf\u8ba1-sps\uff0cpps-\u7b49-nalu-\u7684\u6570\u91cf\">4\uff0c\u7edf\u8ba1 sps\uff0cpps \u7b49 NALU \u7684\u6570\u91cf<\/h4>\n\n\n\n<p>\u5f53\u901a\u8fc7&nbsp;<code class=\"prettyprint\" >zero_ref<\/code>&nbsp;\u7684\u5224\u65ad\u4e4b\u540e\uff0c\u5c31\u4ee3\u8868\u8fd9\u4e2a NALU \u662f\u7b26\u5408 H.264 \u6807\u51c6\u7684\u3002\u7136\u540e\u6839\u636e&nbsp;<code>type<\/code>&nbsp;\u6765\u5224\u65ad NALU \u7684\u7c7b\u578b\uff0c\u6765\u7edf\u8ba1 NALU\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/demuxer\/h264_probe\/1-6.png\" alt=\"1-6\"\/><\/figure>\n\n\n\n<p>\u6700\u540e\uff0c\u5982\u679c\u627e\u5230&nbsp;<code class=\"prettyprint\" >sps<\/code>\uff0c<code>pps<\/code>&nbsp;\u7b49 NALU \u6570\u636e\uff0c<code>h264_probe()<\/code>&nbsp;\u51fd\u6570\u8fd4\u56de\u7684\u5206\u6570\u5c31\u4f1a\u5f88\u9ad8\uff0c\u5c31\u53ef\u4ee5\u63a2\u6d4b\u51fa\u6765\u8f93\u5165\u7684\u6570\u636e\u662f h.264 \u4e86\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><code class=\"prettyprint\" >h264_probe()<\/code>&nbsp;\u51fd\u6570\u91cc\u9762\u8fd8\u6709\u4e00\u4e9b\u4ee3\u7801\u662f\u6ca1\u6709\u8bb2\u89e3\u7684\uff0c\u8bf7\u8bfb\u8005\u81ea\u884c\u601d\u8003\uff0c\u5982\u4e0b\uff1a<\/p>\n\n\n\n<h5 class=\"wp-block-heading\" id=\"1\uff0c\u53d8\u91cf-res-\u4ee3\u8868\u4ec0\u4e48\uff1f\">1\uff0c\u53d8\u91cf&nbsp;<code class=\"prettyprint\" >res<\/code>&nbsp;\u4ee3\u8868\u4ec0\u4e48\uff1f<\/h5>\n\n\n\n<p><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >if (ref_zero&#091;type] == 2) {\n    if (!(code == 0x100 &amp;&amp; !p-&gt;buf&#091;i + 1] &amp;&amp; !p-&gt;buf&#091;i + 2]))\n        res++;\n}<\/code><\/pre>\n\n\n\n<p><\/p>\n\n\n\n<h5 class=\"wp-block-heading\" id=\"2\uff0c\u51fd\u6570-initgetbits8-\u6709\u4f55\u4f5c\u7528\uff1f\">2\uff0c\u51fd\u6570&nbsp;<code class=\"prettyprint\" >init_get_bits8()<\/code>&nbsp;\u6709\u4f55\u4f5c\u7528\uff1f<\/h5>\n\n\n\n<p><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code class=\"prettyprint\" >ret = init_get_bits8(&amp;gb, p-&gt;buf + i + 1, p-&gt;buf_size - i - 1);<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/ffmpeg.xianwaizhiyin.net\/pdf-buy.html\"><img decoding=\"async\" src=\"https:\/\/ffmpeg.xianwaizhiyin.net\/img\/bottom_ad_ffmpeg.jpg\" alt=\"\"\/><\/a><\/figure>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>\u4f5c\u8005\uff1a\u7f57\u4e0a\u6587\uff0c\u5fae\u4fe1\uff1aLoken1\uff0c\u516c\u4f17\u53f7\uff1aFFmpeg\u5f26\u5916\u4e4b\u97f3 \u672c\u6587\u4f7f\u7528\u7684\u547d\u4ee4\u5982\u4e0b\uff1a \u8bf7\u53c2\u8003\u300a\u7528Ubuntu1 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3084","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v18.2 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>h264_probe\u63a2\u6d4bh264\u683c\u5f0f\u2014FFmpeg\u6e90\u7801\u5206\u6790 - \u5f26\u5916\u4e4b\u97f3<\/title>\n<meta name=\"description\" content=\"h264_probe() \u51fd\u6570\u7684\u91cd\u70b9\u5982\u4e0b\uff1a1\uff0c\u627e\u5230\u6bcf\u4e2a NALU \u7684\u5f00\u5934\uff1b3\uff0cref_zero \u5224\u65ad NALU \u662f\u5426\u7b26\u5408H.264\u6807\u51c6\uff1b4\uff0c\u7edf\u8ba1 sps\uff0cpps \u7b49 NALU \u7684\u6570\u91cf\u6253\u5206\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.xianwaizhiyin.net\/?p=3084\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"h264_probe\u63a2\u6d4bh264\u683c\u5f0f\u2014FFmpeg\u6e90\u7801\u5206\u6790 - \u5f26\u5916\u4e4b\u97f3\" \/>\n<meta property=\"og:description\" content=\"h264_probe() \u51fd\u6570\u7684\u91cd\u70b9\u5982\u4e0b\uff1a1\uff0c\u627e\u5230\u6bcf\u4e2a NALU \u7684\u5f00\u5934\uff1b3\uff0cref_zero \u5224\u65ad NALU 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