{"id":465,"date":"2025-03-26T16:54:44","date_gmt":"2025-03-26T08:54:44","guid":{"rendered":"https:\/\/trantor.ink\/?p=465"},"modified":"2025-03-26T16:55:33","modified_gmt":"2025-03-26T08:55:33","slug":"exoplayer-%e4%bb%a3%e7%a0%81%e7%89%87%e6%ae%b5%e9%80%bb%e8%be%91%e5%88%86%e6%9e%90","status":"publish","type":"post","link":"https:\/\/trantor.ink\/?p=465","title":{"rendered":"exoplayer \u4ee3\u7801\u7247\u6bb5\u903b\u8f91\u5206\u6790"},"content":{"rendered":"\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">  private fun getDefaultBufferSizeInBytes(audioFormat: AudioProcessor.AudioFormat): Int {\n        val outputPcmFrameSize = Util.getPcmFrameSize(audioFormat.encoding, audioFormat.channelCount)\n        val minBufferSize =\n            AudioTrack.getMinBufferSize(\n                audioFormat.sampleRate,\n                Util.getAudioTrackChannelConfig(audioFormat.channelCount),\n                audioFormat.encoding\n            )\n        Assertions.checkState(minBufferSize != ERROR_BAD_VALUE)\n        val multipliedBufferSize = minBufferSize * EXO_BUFFER_MULTIPLICATION_FACTOR\n        val minAppBufferSize =\n            durationUsToFrames(EXO_MIN_BUFFER_DURATION_US).toInt() * outputPcmFrameSize\n        val maxAppBufferSize = max(\n            minBufferSize.toLong(),\n            durationUsToFrames(EXO_MAX_BUFFER_DURATION_US) * outputPcmFrameSize\n        ).toInt()\n        val bufferSizeInFrames = Util.constrainValue(\n            multipliedBufferSize,\n            minAppBufferSize,\n            maxAppBufferSize\n        ) \/ outputPcmFrameSize\n        return bufferSizeInFrames * outputPcmFrameSize\n    }<\/pre>\n\n\n\n<p>\u8fd9\u6bb5\u4ee3\u7801\u662f\u7528\u4e8e\u8ba1\u7b97 <strong>\u9ed8\u8ba4\u97f3\u9891\u7f13\u51b2\u533a\u5927\u5c0f<\/strong> \u7684\u65b9\u6cd5\uff0c\u901a\u5e38\u7528\u4e8e AudioTrack \u914d\u7f6e\uff0c\u4ee5\u786e\u4fdd\u97f3\u9891\u64ad\u653e\u6d41\u7545\u4e14\u5ef6\u8fdf\u4f4e\u3002\u5b83\u7684\u4f5c\u7528\u662f\uff1a<\/p>\n\n\n\n<p>1. <strong>\u8ba1\u7b97 PCM \u5e27\u5927\u5c0f<\/strong><\/p>\n\n\n\n<p>2. <strong>\u83b7\u53d6 AudioTrack \u6700\u5c0f\u7f13\u51b2\u533a<\/strong><\/p>\n\n\n\n<p>3. <strong>\u6269\u5c55\u7f13\u51b2\u533a\u5927\u5c0f\uff0c\u786e\u4fdd\u5e94\u7528\u5c42\u7f13\u51b2\u533a\u9002\u5408\u4e0d\u540c\u573a\u666f<\/strong><\/p>\n\n\n\n<p>4. <strong>\u5728\u5408\u7406\u8303\u56f4\u5185\u8c03\u6574\u7f13\u51b2\u533a\u5927\u5c0f<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>\u8be6\u7ec6\u89e3\u6790<\/strong><\/p>\n\n\n\n<p><strong>1. \u83b7\u53d6 PCM \u5e27\u5927\u5c0f<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">val outputPcmFrameSize = Util.getPcmFrameSize(audioFormat.encoding, audioFormat.channelCount)<\/pre>\n\n\n\n<p>\u2022 Util.getPcmFrameSize(encoding, channelCount) \u8ba1\u7b97 <strong>\u6bcf\u4e2a PCM \u91c7\u6837\u5e27\u7684\u5b57\u8282\u5927\u5c0f<\/strong>\u3002<\/p>\n\n\n\n<p>\u2022 <strong>\u793a\u4f8b<\/strong>\uff1a<\/p>\n\n\n\n<p>\u2022 <strong>PCM 16-bit<\/strong>\uff0c\u53cc\u58f0\u9053\uff1a2 (bytes per sample) \u00d7 2 (channels) = 4 bytes per frame<\/p>\n\n\n\n<p>\u2022 <strong>PCM 8-bit<\/strong>\uff0c\u5355\u58f0\u9053\uff1a1 (bytes per sample) \u00d7 1 (channel) = 1 byte per frame<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>2. \u83b7\u53d6 AudioTrack \u5141\u8bb8\u7684\u6700\u5c0f\u7f13\u51b2\u533a<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">val minBufferSize =\n    AudioTrack.getMinBufferSize(\n        audioFormat.sampleRate,\n        Util.getAudioTrackChannelConfig(audioFormat.channelCount),\n        audioFormat.encoding\n    )<\/pre>\n\n\n\n<p>\u2022 AudioTrack.getMinBufferSize() <strong>\u83b7\u53d6 Android \u7cfb\u7edf\u63a8\u8350\u7684\u6700\u5c0f\u97f3\u9891\u7f13\u51b2\u533a\u5927\u5c0f\uff08\u4ee5\u5b57\u8282\u4e3a\u5355\u4f4d\uff09<\/strong>\u3002<\/p>\n\n\n\n<p>\u2022 Util.getAudioTrackChannelConfig(audioFormat.channelCount) <strong>\u8f6c\u6362\u58f0\u9053\u6570\u5230 AudioTrack \u914d\u7f6e<\/strong>\uff0c\u5982\uff1a<\/p>\n\n\n\n<p>\u2022 \u5355\u58f0\u9053\uff081 channel\uff09\uff1aAudioFormat.CHANNEL_OUT_MONO<\/p>\n\n\n\n<p>\u2022 \u7acb\u4f53\u58f0\uff082 channels\uff09\uff1aAudioFormat.CHANNEL_OUT_STEREO<\/p>\n\n\n\n<p>\u2022 audioFormat.encoding \u662f\u97f3\u9891\u683c\u5f0f\uff0c\u5982 ENCODING_PCM_16BIT\u3002<\/p>\n\n\n\n<p>\u5982\u679c getMinBufferSize() \u8fd4\u56de ERROR_BAD_VALUE\uff0c\u8868\u793a\u683c\u5f0f\u4e0d\u652f\u6301\uff0c\u7a0b\u5e8f\u4f1a\u629b\u51fa\u5f02\u5e38\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">Assertions.checkState(minBufferSize != ERROR_BAD_VALUE)<\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>3. \u6269\u5c55\u7f13\u51b2\u533a\u5927\u5c0f<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">val multipliedBufferSize = minBufferSize * EXO_BUFFER_MULTIPLICATION_FACTOR<\/pre>\n\n\n\n<p>\u2022 EXO_BUFFER_MULTIPLICATION_FACTOR <strong>\u7528\u4e8e\u6269\u5c55\u7f13\u51b2\u533a\u5927\u5c0f<\/strong>\uff0c\u786e\u4fdd\u64ad\u653e\u4e0d\u5361\u987f\u3002<\/p>\n\n\n\n<p>\u2022 <strong>\u4e3a\u4ec0\u4e48\u6269\u5c55\uff1f<\/strong><\/p>\n\n\n\n<p>\u2022 Android \u63d0\u4f9b\u7684 minBufferSize \u53ef\u80fd\u4e0d\u8db3\u4ee5\u5904\u7406\u6240\u6709\u573a\u666f\uff0c\u6bd4\u5982\u8f83\u9ad8\u7684 sampleRate \u53ef\u80fd\u9700\u8981\u66f4\u5927\u7f13\u51b2\u533a\u3002<\/p>\n\n\n\n<p>\u2022 \u4f8b\u5982\uff0c<strong>\u5982\u679c minBufferSize = 8192 \u4e14 EXO_BUFFER_MULTIPLICATION_FACTOR = 4\uff0c\u5219 multipliedBufferSize = 32768<\/strong>\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>4. \u8ba1\u7b97 minAppBufferSize<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">val minAppBufferSize =\n    durationUsToFrames(EXO_MIN_BUFFER_DURATION_US).toInt() * outputPcmFrameSize<\/pre>\n\n\n\n<p>\u2022 EXO_MIN_BUFFER_DURATION_US \u662f <strong>\u6700\u5c0f\u7f13\u51b2\u533a\u6301\u7eed\u65f6\u95f4\uff08\u5355\u4f4d\uff1a\u5fae\u79d2\uff09<\/strong>\uff0c\u6bd4\u5982 250000\uff08250ms\uff09\u3002<\/p>\n\n\n\n<p>\u2022 durationUsToFrames(EXO_MIN_BUFFER_DURATION_US) <strong>\u5c06\u6301\u7eed\u65f6\u95f4\u8f6c\u6362\u4e3a\u5e27\u6570<\/strong>\u3002<\/p>\n\n\n\n<p>\u2022 frames = (\u91c7\u6837\u7387 \u00d7 \u6301\u7eed\u65f6\u95f4) \/ 1_000_000<\/p>\n\n\n\n<p>\u2022 \u4f8b\u5982 44100 Hz\uff0c250ms\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">frames = (44100 \u00d7 250000) \/ 1_000_000 = 11025 frames<\/pre>\n\n\n\n<p>\u2022 \u8ba1\u7b97\u51fa\u7684\u5e27\u6570\u518d <strong>\u4e58\u4ee5 outputPcmFrameSize<\/strong>\uff0c\u5f97\u5230\u4ee5 <strong>\u5b57\u8282\u4e3a\u5355\u4f4d<\/strong> \u7684\u7f13\u51b2\u533a\u5927\u5c0f\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>5. \u8ba1\u7b97 maxAppBufferSize<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">val maxAppBufferSize = max(\n    minBufferSize.toLong(),\n    durationUsToFrames(EXO_MAX_BUFFER_DURATION_US) * outputPcmFrameSize\n).toInt()<\/pre>\n\n\n\n<p>\u2022 EXO_MAX_BUFFER_DURATION_US <strong>\u662f\u6700\u5927\u7f13\u51b2\u533a\u6301\u7eed\u65f6\u95f4<\/strong>\uff08\u6bd4\u5982 750ms\uff09\u3002<\/p>\n\n\n\n<p>\u2022 \u8ba1\u7b97\u65b9\u6cd5\u540c minAppBufferSize\uff0c\u4f46\u8fd9\u91cc\u53d6 minBufferSize \u548c maxBufferSize <strong>\u7684\u6700\u5927\u503c<\/strong>\uff0c\u4fdd\u8bc1\u7f13\u51b2\u533a\u8db3\u591f\u5927\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>6. \u8ba1\u7b97\u6700\u7ec8\u7684\u7f13\u51b2\u533a\u5927\u5c0f<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">val bufferSizeInFrames = Util.constrainValue(\n    multipliedBufferSize,\n    minAppBufferSize,\n    maxAppBufferSize\n) \/ outputPcmFrameSize\nreturn bufferSizeInFrames * outputPcmFrameSize<\/pre>\n\n\n\n<p>\u2022 Util.constrainValue(value, min, max) <strong>\u786e\u4fdd multipliedBufferSize \u5728 minAppBufferSize \u548c maxAppBufferSize \u4e4b\u95f4<\/strong>\u3002<\/p>\n\n\n\n<p>\u2022 <strong>\u6700\u540e\u8f6c\u6362\u56de\u5b57\u8282\u5355\u4f4d<\/strong>\uff0c\u8fd4\u56de\u6700\u7ec8\u7684\u7f13\u51b2\u533a\u5927\u5c0f\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>\u5b8c\u6574\u6d41\u7a0b\u793a\u4f8b<\/strong><\/p>\n\n\n\n<p>\u5047\u8bbe\uff1a<\/p>\n\n\n\n<p>\u2022 <strong>\u91c7\u6837\u7387<\/strong>\uff1a44100 Hz<\/p>\n\n\n\n<p>\u2022 <strong>\u58f0\u9053\u6570<\/strong>\uff1a2\uff08\u7acb\u4f53\u58f0\uff09<\/p>\n\n\n\n<p>\u2022 <strong>\u683c\u5f0f<\/strong>\uff1aPCM 16-bit<\/p>\n\n\n\n<p>\u2022 <strong>EXO_MIN_BUFFER_DURATION_US = 250_000\uff08250ms\uff09<\/strong><\/p>\n\n\n\n<p>\u2022 <strong>EXO_MAX_BUFFER_DURATION_US = 750_000\uff08750ms\uff09<\/strong><\/p>\n\n\n\n<p>\u2022 <strong>EXO_BUFFER_MULTIPLICATION_FACTOR = 4<\/strong><\/p>\n\n\n\n<p>\u90a3\u4e48\uff1a<\/p>\n\n\n\n<p>1. <strong>\u8ba1\u7b97 PCM \u5e27\u5927\u5c0f<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">outputPcmFrameSize = 2 bytes * 2 channels = 4 bytes<\/pre>\n\n\n\n<p>2. <strong>\u83b7\u53d6 minBufferSize<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">minBufferSize = AudioTrack.getMinBufferSize(44100, CHANNEL_OUT_STEREO, ENCODING_PCM_16BIT)\nminBufferSize = 8192 bytes<\/pre>\n\n\n\n<p>3. <strong>\u6269\u5c55\u7f13\u51b2\u533a<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">multipliedBufferSize = 8192 * 4 = 32768 bytes<\/pre>\n\n\n\n<p>4. <strong>\u8ba1\u7b97 minAppBufferSize<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">minAppBufferSize = (44100 \u00d7 250_000 \/ 1_000_000) * 4 = 11025 * 4 = 44100 bytes<\/pre>\n\n\n\n<p>5. <strong>\u8ba1\u7b97 maxAppBufferSize<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">maxAppBufferSize = max(8192, (44100 \u00d7 750_000 \/ 1_000_000) * 4)\n                  = max(8192, 33075 * 4)\n                  = max(8192, 132300)\n                  = 132300 bytes<\/pre>\n\n\n\n<p>6. <strong>\u8ba1\u7b97\u6700\u7ec8\u7f13\u51b2\u533a\u5927\u5c0f<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">bufferSizeInFrames = constrainValue(32768, 44100, 132300) \/ 4\n                   = 44100 \/ 4\n                   = 11025 frames\nreturn 11025 * 4 = 44100 bytes<\/pre>\n\n\n\n<p>\u6700\u7ec8\u7f13\u51b2\u533a\u5927\u5c0f\uff1a<strong>44100 bytes\uff0844 KB\uff09<\/strong>\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>\u603b\u7ed3<\/strong><\/p>\n\n\n\n<p>\u2022 <strong>\u76ee\u7684\u662f\u8ba1\u7b97\u5408\u9002\u7684\u97f3\u9891\u7f13\u51b2\u533a\u5927\u5c0f<\/strong>\uff0c\u65e2\u4e0d\u4f1a\u592a\u5c0f\uff08\u5bfc\u81f4\u97f3\u9891\u4e2d\u65ad\uff09\uff0c\u4e5f\u4e0d\u4f1a\u592a\u5927\uff08\u589e\u52a0\u5ef6\u8fdf\uff09\u3002<\/p>\n\n\n\n<p>\u2022 <strong>\u786e\u4fdd AudioTrack \u53ef\u4ee5\u6d41\u7545\u64ad\u653e<\/strong>\uff0c\u907f\u514d Buffer Underrun\uff08\u7f13\u51b2\u533a\u6570\u636e\u4e0d\u8db3\uff09\u3002<\/p>\n\n\n\n<p>\u2022 <strong>\u52a8\u6001\u8c03\u6574<\/strong>\uff0c\u57fa\u4e8e\u97f3\u9891\u91c7\u6837\u7387\u3001\u683c\u5f0f\u548c\u6700\u5c0f\/\u6700\u5927\u7f13\u51b2\u533a\u5927\u5c0f\u3002<\/p>\n\n\n\n<p>\u8fd9\u6bb5\u4ee3\u7801\u4f18\u5316\u4e86 <strong>\u97f3\u9891\u64ad\u653e\u7684\u7a33\u5b9a\u6027<\/strong> \u548c <strong>\u4f4e\u5ef6\u8fdf\u6027<\/strong>\uff0c\u5728 ExoPlayer \u97f3\u9891\u5904\u7406\u6d41\u7a0b\u4e2d\u975e\u5e38\u91cd\u8981\u3002 \ud83c\udfb5<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u8fd9\u6bb5\u4ee3\u7801\u662f\u7528\u4e8e\u8ba1\u7b97 \u9ed8\u8ba4\u97f3\u9891\u7f13\u51b2\u533a\u5927\u5c0f \u7684\u65b9\u6cd5\uff0c\u901a\u5e38\u7528\u4e8e AudioTrack \u914d\u7f6e\uff0c\u4ee5\u786e\u4fdd\u97f3\u9891\u64ad\u653e\u6d41\u7545\u4e14\u5ef6\u8fdf\u4f4e\u3002\u5b83\u7684\u4f5c\u7528\u662f\uff1a 1. \u8ba1\u7b97 PCM \u5e27\u5927\u5c0f 2. \u83b7\u53d6 AudioTrack \u6700\u5c0f\u7f13\u51b2\u533a 3. \u6269\u5c55\u7f13\u51b2\u533a\u5927\u5c0f\uff0c\u786e\u4fdd\u5e94\u7528\u5c42\u7f13\u51b2\u533a\u9002\u5408\u4e0d\u540c\u573a\u666f 4. \u5728\u5408\u7406\u8303\u56f4\u5185\u8c03\u6574\u7f13\u51b2\u533a\u5927\u5c0f \u8be6\u7ec6\u89e3\u6790 1. \u83b7\u53d6 PCM \u5e27\u5927\u5c0f \u2022 Util.getPcmFrameSize(encoding, channelCount) \u8ba1\u7b97 \u6bcf\u4e2a PCM \u91c7\u6837\u5e27\u7684\u5b57\u8282\u5927\u5c0f\u3002 \u2022 \u793a\u4f8b\uff1a \u2022 PCM 16-bit\uff0c\u53cc\u58f0\u9053\uff1a2 (bytes per sample) \u00d7 2 (channels) = 4 bytes per frame \u2022 PCM 8-bit\uff0c\u5355\u58f0\u9053\uff1a1 (bytes per sample) \u00d7 1 (channel) = 1 byte per frame 2. \u83b7\u53d6 AudioTrack \u5141\u8bb8\u7684\u6700\u5c0f\u7f13\u51b2\u533a \u2022 AudioTrack.getMinBufferSize() \u83b7\u53d6 Android \u7cfb\u7edf\u63a8\u8350\u7684\u6700\u5c0f\u97f3\u9891\u7f13\u51b2\u533a\u5927\u5c0f\uff08\u4ee5\u5b57\u8282\u4e3a\u5355\u4f4d\uff09\u3002 \u2022 Util.getAudioTrackChannelConfig(audioFormat.channelCount) \u8f6c\u6362\u58f0\u9053\u6570\u5230 AudioTrack \u914d\u7f6e\uff0c\u5982\uff1a \u2022 \u5355\u58f0\u9053\uff081 channel\uff09\uff1aAudioFormat.CHANNEL_OUT_MONO \u2022 \u7acb\u4f53\u58f0\uff082 channels\uff09\uff1aAudioFormat.CHANNEL_OUT_STEREO \u2022 audioFormat.encoding \u662f\u97f3\u9891\u683c\u5f0f\uff0c\u5982 ENCODING_PCM_16BIT\u3002 \u5982\u679c getMinBufferSize() \u8fd4\u56de ERROR_BAD_VALUE\uff0c\u8868\u793a\u683c\u5f0f\u4e0d\u652f\u6301\uff0c\u7a0b\u5e8f\u4f1a\u629b\u51fa\u5f02\u5e38\uff1a 3. \u6269\u5c55\u7f13\u51b2\u533a\u5927\u5c0f \u2022 EXO_BUFFER_MULTIPLICATION_FACTOR \u7528\u4e8e\u6269\u5c55\u7f13\u51b2\u533a\u5927\u5c0f\uff0c\u786e\u4fdd\u64ad\u653e\u4e0d\u5361\u987f\u3002 \u2022 \u4e3a\u4ec0\u4e48\u6269\u5c55\uff1f \u2022 Android \u63d0\u4f9b\u7684 minBufferSize \u53ef\u80fd\u4e0d\u8db3\u4ee5\u5904\u7406\u6240\u6709\u573a\u666f\uff0c\u6bd4\u5982\u8f83\u9ad8\u7684 sampleRate \u53ef\u80fd\u9700\u8981\u66f4\u5927\u7f13\u51b2\u533a\u3002 \u2022 \u4f8b\u5982\uff0c\u5982\u679c minBufferSize = 8192 \u4e14 EXO_BUFFER_MULTIPLICATION_FACTOR = 4\uff0c\u5219 multipliedBufferSize = 32768\u3002 4. \u8ba1\u7b97 minAppBufferSize \u2022 EXO_MIN_BUFFER_DURATION_US \u662f \u6700\u5c0f\u7f13\u51b2\u533a\u6301\u7eed\u65f6\u95f4\uff08\u5355\u4f4d\uff1a\u5fae\u79d2\uff09\uff0c\u6bd4\u5982 250000\uff08250ms\uff09\u3002 \u2022 durationUsToFrames(EXO_MIN_BUFFER_DURATION_US) \u5c06\u6301\u7eed\u65f6\u95f4\u8f6c\u6362\u4e3a\u5e27\u6570\u3002 \u2022 frames = (\u91c7\u6837\u7387 \u00d7 \u6301\u7eed\u65f6\u95f4) \/ 1_000_000 \u2022 \u4f8b\u5982 44100 Hz\uff0c250ms\uff1a \u2022 \u8ba1\u7b97\u51fa\u7684\u5e27\u6570\u518d \u4e58\u4ee5 outputPcmFrameSize\uff0c\u5f97\u5230\u4ee5 \u5b57\u8282\u4e3a\u5355\u4f4d \u7684\u7f13\u51b2\u533a\u5927\u5c0f\u3002 5. \u8ba1\u7b97 maxAppBufferSize \u2022 EXO_MAX_BUFFER_DURATION_US \u662f\u6700\u5927\u7f13\u51b2\u533a\u6301\u7eed\u65f6\u95f4\uff08\u6bd4\u5982 750ms\uff09\u3002 \u2022 \u8ba1\u7b97\u65b9\u6cd5\u540c minAppBufferSize\uff0c\u4f46\u8fd9\u91cc\u53d6 minBufferSize \u548c maxBufferSize \u7684\u6700\u5927\u503c\uff0c\u4fdd\u8bc1\u7f13\u51b2\u533a\u8db3\u591f\u5927\u3002 6. \u8ba1\u7b97\u6700\u7ec8\u7684\u7f13\u51b2\u533a\u5927\u5c0f \u2022 Util.constrainValue(value, min, max) \u786e\u4fdd multipliedBufferSize \u5728 minAppBufferSize \u548c maxAppBufferSize \u4e4b\u95f4\u3002 \u2022 \u6700\u540e\u8f6c\u6362\u56de\u5b57\u8282\u5355\u4f4d\uff0c\u8fd4\u56de\u6700\u7ec8\u7684\u7f13\u51b2\u533a\u5927\u5c0f\u3002 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