# agora::rtc 命名空间参考 (/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc)

> For AI agents: see the complete documentation index at [llms.txt](/llms.txt).

## 类型定义说明 [#类型定义说明]

<a id="ab650539cb2bdcf8382d0aa32c6d70aa7"></a>

### uid_t [#uid_t]

<ApiSignature>

typedef unsigned int [agora::rtc::uid_t](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ab650539cb2bdcf8382d0aa32c6d70aa7)

</ApiSignature>

<a id="a728a2a0d7515f2c3376614be00173f7d"></a>

### track_id_t [#track_id_t]

<ApiSignature>

typedef unsigned int [agora::rtc::track_id_t](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a728a2a0d7515f2c3376614be00173f7d)

</ApiSignature>

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### conn_id_t [#conn_id_t]

<ApiSignature>

typedef unsigned int [agora::rtc::conn_id_t](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ab669d53cb37e3274112d7fba3eaa27d9)

</ApiSignature>

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### USER_OFFLINE_REASON_TYPE [#user_offline_reason_type]

<ApiSignature>

enum [agora::rtc::USER_OFFLINE_REASON_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a56ebc30a718928cb6998ba1424900fef)

</ApiSignature>

用户离线原因。

<DocsTable>
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<a id="a56ebc30a718928cb6998ba1424900fefa39836e44dee02db52ccebf4f8d963422"></a>USER_OFFLINE_QUIT

</td>
<td>0: 用户主动离开。</td>
</tr>
<tr>
<td>

<a id="a56ebc30a718928cb6998ba1424900fefab534ea4a1a5d4fcd4932d50f4e0e96d1"></a>USER_OFFLINE_DROPPED

</td>
<td>1\:因过长时间收不到对方数据包，超时掉线。由于 SDK 使用的是不可靠通道，也有可能对方主动离开频道，但是本地没收到对方离开消息而误判为超时掉线。</td>
</tr>
<tr>
<td>

<a id="a56ebc30a718928cb6998ba1424900fefa2f31868fc17153cb1d798dad13905d32"></a>USER_OFFLINE_BECOME_AUDIENCE

</td>
<td>2: 用户身份从主播切换为观众。</td>
</tr>
</tbody>
</DocsTable>

<a id="aeaf419fcafaa4d58da8b6d8718e31891"></a>

### QUALITY_TYPE [#quality_type]

<ApiSignature>

enum [agora::rtc::QUALITY_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#aeaf419fcafaa4d58da8b6d8718e31891)

</ApiSignature>

网络质量类型。

<DocsTable>
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<a id="aeaf419fcafaa4d58da8b6d8718e31891aa5c479e59fe69f38a52040a3f4d19380"></a>QUALITY_UNKNOWN

</td>
<td>0: 质量未知。</td>
</tr>
<tr>
<td>

<a id="aeaf419fcafaa4d58da8b6d8718e31891aed27e4baacc04a6ae99e063e01db3694"></a>QUALITY_EXCELLENT

</td>
<td>1: 质量极好。</td>
</tr>
<tr>
<td>

<a id="aeaf419fcafaa4d58da8b6d8718e31891a75cf9305a451fcb53279a2e628d78c16"></a>QUALITY_GOOD

</td>
<td>2: 用户主观感觉和极好差不多，但码率可能略低于极好。</td>
</tr>
<tr>
<td>

<a id="aeaf419fcafaa4d58da8b6d8718e31891a4bcf1cac434df6a62b56210f065dc6cb"></a>QUALITY_POOR

</td>
<td>3: 用户主观感受有瑕疵但不影响沟通。</td>
</tr>
<tr>
<td>

<a id="aeaf419fcafaa4d58da8b6d8718e31891a2783cf640eaf1505575b2812da79f396"></a>QUALITY_BAD

</td>
<td>4: 勉强能沟通但不顺畅。</td>
</tr>
<tr>
<td>

<a id="aeaf419fcafaa4d58da8b6d8718e31891ab362c6bae120ac210b506120a95cf940"></a>QUALITY_VBAD

</td>
<td>5: 网络质量非常差，基本不能沟通。</td>
</tr>
<tr>
<td>

<a id="aeaf419fcafaa4d58da8b6d8718e31891aed391bbc2c9e747b36bdf76997bb8221"></a>QUALITY_DOWN

</td>
<td>6: 网络连接断开，完全无法沟通。</td>
</tr>
</tbody>
</DocsTable>

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### VIDEO_ORIENTATION [#video_orientation]

<ApiSignature>

enum [agora::rtc::VIDEO_ORIENTATION](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#aedbc3d09c641940779abc983aa3ee3bc)

</ApiSignature>

视频旋转信息。

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<a id="aedbc3d09c641940779abc983aa3ee3bca3383b6c7e915840bc3608662ea4fae4d"></a>VIDEO_ORIENTATION_0

</td>
<td>0: 顺时针旋转 0 度。</td>
</tr>
<tr>
<td>

<a id="aedbc3d09c641940779abc983aa3ee3bca6608e1f19f9838ff0f570adf248a5343"></a>VIDEO_ORIENTATION_90

</td>
<td>90: 顺时针旋转 90 度。</td>
</tr>
<tr>
<td>

<a id="aedbc3d09c641940779abc983aa3ee3bca6e0af5872680eb93aae8bbf93d2d3382"></a>VIDEO_ORIENTATION_180

</td>
<td>180: 顺时针旋转 180 度。</td>
</tr>
<tr>
<td>

<a id="aedbc3d09c641940779abc983aa3ee3bca0d0688309a8c979440800c7e2951f856"></a>VIDEO_ORIENTATION_270

</td>
<td>270: 顺时针旋转 270 度。</td>
</tr>
</tbody>
</DocsTable>

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### FRAME_RATE [#frame_rate]

<ApiSignature>

enum [agora::rtc::FRAME_RATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a382d0a93e80539155ebd729e362684f1)

</ApiSignature>

视频帧率。

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<a id="a382d0a93e80539155ebd729e362684f1a977f1cfdcf5b800f993482da6a173cd5"></a>FRAME_RATE_FPS_1

</td>
<td>1: 1 fps</td>
</tr>
<tr>
<td>

<a id="a382d0a93e80539155ebd729e362684f1ad04434616f09899ce747d9411099a3a1"></a>FRAME_RATE_FPS_7

</td>
<td>7: 7 fps</td>
</tr>
<tr>
<td>

<a id="a382d0a93e80539155ebd729e362684f1aa12cac1b6fd0fae6e0d17e300bc16623"></a>FRAME_RATE_FPS_10

</td>
<td>10: 10 fps</td>
</tr>
<tr>
<td>

<a id="a382d0a93e80539155ebd729e362684f1a58bcbb5182037fb47ff30c42eee66710"></a>FRAME_RATE_FPS_15

</td>
<td>15: 15 fps</td>
</tr>
<tr>
<td>

<a id="a382d0a93e80539155ebd729e362684f1a076f14806cad9efc861f4cc1275578e4"></a>FRAME_RATE_FPS_24

</td>
<td>24: 24 fps</td>
</tr>
<tr>
<td>

<a id="a382d0a93e80539155ebd729e362684f1ac9ceedbdf97cbaa1c30a17773e7998db"></a>FRAME_RATE_FPS_30

</td>
<td>30: 30 fps</td>
</tr>
<tr>
<td>

<a id="a382d0a93e80539155ebd729e362684f1ae3b15e53bd5d9107a7aa13e6ed29b825"></a>FRAME_RATE_FPS_60

</td>
<td>60: 60 fps。仅适用于 Windows 和 macOS 平台。</td>
</tr>
</tbody>
</DocsTable>

<a id="a2f07c4ed608d97da9e6bfbdb7723d9dd"></a>

### FRAME_WIDTH [#frame_width]

<ApiSignature>

enum [agora::rtc::FRAME_WIDTH](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a2f07c4ed608d97da9e6bfbdb7723d9dd)

</ApiSignature>

视频帧宽度。

<DocsTable>
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<th colSpan={2} scope="colgroup">枚举值</th>
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<td>

<a id="a2f07c4ed608d97da9e6bfbdb7723d9ddad29e62742c2779d2171051f8be3e9de9"></a>FRAME_WIDTH_640

</td>
<td>640：640 像素</td>
</tr>
</tbody>
</DocsTable>

<a id="a29e02d842f9dbb4284039e6ee31a99f0"></a>

### FRAME_HEIGHT [#frame_height]

<ApiSignature>

enum [agora::rtc::FRAME_HEIGHT](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a29e02d842f9dbb4284039e6ee31a99f0)

</ApiSignature>

视频帧高度。

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<a id="a29e02d842f9dbb4284039e6ee31a99f0aa037e64f88bf0ca7c3d4d20956973c81"></a>FRAME_HEIGHT_360

</td>
<td>360：360 像素</td>
</tr>
</tbody>
</DocsTable>

<a id="aecdd48fd8c80e68e723e4bea97cb4281"></a>

### VIDEO_FRAME_TYPE [#video_frame_type]

<ApiSignature>

enum [agora::rtc::VIDEO_FRAME_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#aecdd48fd8c80e68e723e4bea97cb4281)

</ApiSignature>

视频帧类型。

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<th colSpan={2} scope="colgroup">枚举值</th>
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<td>

<a id="aecdd48fd8c80e68e723e4bea97cb4281a7bf11c6cbcd205e9cc75546528207a93"></a>VIDEO_FRAME_TYPE_BLANK_FRAME

</td>
<td>0：空白帧</td>
</tr>
<tr>
<td>

<a id="aecdd48fd8c80e68e723e4bea97cb4281a6092e565d83e3e0e6b441ca11e21a65e"></a>VIDEO_FRAME_TYPE_KEY_FRAME

</td>
<td>3：关键帧。对于 H.264 编码格式，SDK 把带有 sps 和 pps 信息的 I 帧归类为关键帧。</td>
</tr>
<tr>
<td>

<a id="aecdd48fd8c80e68e723e4bea97cb4281ac20e0af03b67b72c32a9cf44a2854f00"></a>VIDEO_FRAME_TYPE_DELTA_FRAME

</td>
<td>4：Delta 帧。对于 H.264 编码格式，SDK 把 P 帧和不带 sps 和 pps 信息的 I 帧都归类为 Delta 帧。</td>
</tr>
<tr>
<td>

<a id="aecdd48fd8c80e68e723e4bea97cb4281a18eefebf17017d9a7e7b846fe7320f40"></a>VIDEO_FRAME_TYPE_B_FRAME

</td>
<td>5：B 帧</td>
</tr>
<tr>
<td>

<a id="aecdd48fd8c80e68e723e4bea97cb4281a49a7f6c4e570941736c95eb997a91098"></a>VIDEO_FRAME_TYPE_DROPPABLE_FRAME

</td>
<td>6：丢弃帧</td>
</tr>
<tr>
<td>

<a id="aecdd48fd8c80e68e723e4bea97cb4281a5e6a216c6f2dc7491eb0a8b9f1f2487e"></a>VIDEO_FRAME_TYPE_UNKNOW

</td>
<td>7：未知</td>
</tr>
</tbody>
</DocsTable>

<a id="af3d825e24a1e5dcfb74279c69b81d0c7"></a>

### ORIENTATION_MODE [#orientation_mode]

<ApiSignature>

enum [agora::rtc::ORIENTATION_MODE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#af3d825e24a1e5dcfb74279c69b81d0c7)

</ApiSignature>

视频编码的方向模式。

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<th colSpan={2} scope="colgroup">枚举值</th>
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<td>

<a id="af3d825e24a1e5dcfb74279c69b81d0c7a6c9c916656d47771664b0696fbaa39bc"></a>ORIENTATION_MODE_ADAPTIVE

</td>
<td>0: （默认）该模式下 SDK 输出的视频方向与采集到的视频方向一致。接收端会根据收到的视频旋转信息对视频进行旋转。该模式适用于接收端可以调整视频方向的场景。 如果采集的视频是横屏模式，则输出的视频也是横屏模式。 如果采集的视频是竖屏模式，则输出的视频也是竖屏模式。</td>
</tr>
<tr>
<td>

<a id="af3d825e24a1e5dcfb74279c69b81d0c7ac8e505f519b124299c5977b21df29c21"></a>ORIENTATION_MODE_FIXED_LANDSCAPE

</td>
<td>1: 该模式下 SDK 固定输出风景（横屏）模式的视频。如果采集到的视频是竖屏模式，则视频编码器会对其进行裁剪。该模式适用于接收端无法调整视频方向的场景，如直推 CDN。</td>
</tr>
<tr>
<td>

<a id="af3d825e24a1e5dcfb74279c69b81d0c7a26abe8e035ec0867b3603ffccc9248f8"></a>ORIENTATION_MODE_FIXED_PORTRAIT

</td>
<td>2: 该模式下 SDK 固定输出人像（竖屏）模式的视频，如果采集到的视频是横屏模式，则视频编码器会对其进行裁剪。该模式适用于接收端无法调整视频方向的场景，如直推 CDN。</td>
</tr>
</tbody>
</DocsTable>

<a id="ae02c6d4b2848c21a502e4c1643d85ef6"></a>

### DEGRADATION_PREFERENCE [#degradation_preference]

<ApiSignature>

enum [agora::rtc::DEGRADATION_PREFERENCE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ae02c6d4b2848c21a502e4c1643d85ef6)

</ApiSignature>

带宽受限时的视频编码降级偏好。

<DocsTable>
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<td>

<a id="ae02c6d4b2848c21a502e4c1643d85ef6ac80182fd2f0983d09e5e6841c6020729"></a>MAINTAIN_QUALITY

</td>
<td>0: （默认）带宽受限时，视频编码时优先降低视频帧率，维持视频质量不变。该降级偏好适用于画质优先的场景。</td>
</tr>
<tr>
<td>

<a id="ae02c6d4b2848c21a502e4c1643d85ef6a0334a246d5ad15fc9c8a9b4bc3c5fdd7"></a>MAINTAIN_FRAMERATE

</td>
<td>1: 带宽受限时，视频编码时优先降低视频质量，维持视频帧率不变。该降级偏好适用于流畅性优先且允许画质降低的场景。</td>
</tr>
<tr>
<td>

<a id="ae02c6d4b2848c21a502e4c1643d85ef6abac0022e3068e6435d9bc50db18983ac"></a>MAINTAIN_BALANCED

</td>
<td>2: 带宽受限时，视频编码时同时降低视频帧率和视频质量。MAINTAIN_BALANCED 的降幅比 MAINTAIN_QUALITY 和 MAINTAIN_FRAMERATE 降幅更低， 适用于流畅性和画质均有限的场景。</td>
</tr>
<tr>
<td>

<a id="ae02c6d4b2848c21a502e4c1643d85ef6adc9377a20e6d6e8c686a5fe44e13a5c2"></a>MAINTAIN_RESOLUTION

</td>
<td>3: 带宽受限时，视频编码时优先降低视频帧率。</td>
</tr>
</tbody>
</DocsTable>

<a id="a79ccac2a3f394deae680761453d15215"></a>

### VIDEO_CODEC_TYPE [#video_codec_type]

<ApiSignature>

enum [agora::rtc::VIDEO_CODEC_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a79ccac2a3f394deae680761453d15215)

</ApiSignature>

视频编码类型。

<DocsTable>
<thead>
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<th colSpan={2} scope="colgroup">枚举值</th>
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<tbody>
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<td>

<a id="a79ccac2a3f394deae680761453d15215ab9372940cb7e4d55d9ddd5dd602e9bcd"></a>VIDEO_CODEC_NONE

</td>
<td>0: 无</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215af329da3c92373846ea20233787353237"></a>VIDEO_CODEC_VP8

</td>
<td>1: VP8</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215a6fcc2382c1d5bbc07d14db66fd9d6574"></a>VIDEO_CODEC_H264

</td>
<td>2: H.264</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215a382e3099cc94622b11fbbe0d71a73cd2"></a>VIDEO_CODEC_H265

</td>
<td>3: H.265</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215a52b54b2dd05570f3333935d7afab9a7f"></a>VIDEO_CODEC_VP9

</td>
<td>5: VP9</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215a742d2b12d33fb9f54afc97a5d14211cd"></a>VIDEO_CODEC_GENERIC

</td>
<td>6: Generic</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215a2effe3d56056678fa3d5c29bf79be2bf"></a>VIDEO_CODEC_GENERIC_H264

</td>
<td>7: Generic H264</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215a5825fdb6f7017fbc95cef506b811193f"></a>VIDEO_CODEC_AV1

</td>
<td>12: AV1</td>
</tr>
<tr>
<td>

<a id="a79ccac2a3f394deae680761453d15215a3c72dac48d1512ad4094fe1429d54c58"></a>VIDEO_CODEC_GENERIC_JPEG

</td>
<td>20: JPEG</td>
</tr>
</tbody>
</DocsTable>

<a id="ac211c1a503d38d504c92b5f006240053"></a>

### AUDIO_CODEC_TYPE [#audio_codec_type]

<ApiSignature>

enum [agora::rtc::AUDIO_CODEC_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ac211c1a503d38d504c92b5f006240053)

</ApiSignature>

音频编码类型。

<DocsTable>
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<th colSpan={2} scope="colgroup">枚举值</th>
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</thead>
<tbody>
<tr>
<td>

<a id="ac211c1a503d38d504c92b5f006240053a618295ffbcd36987358d5630568fe0fb"></a>AUDIO_CODEC_OPUS

</td>
<td>1: OPUS</td>
</tr>
<tr>
<td>

<a id="ac211c1a503d38d504c92b5f006240053ad8c446b4ba583f021ba164c0be9a15e3"></a>AUDIO_CODEC_PCMA

</td>
<td>3: PCMA</td>
</tr>
<tr>
<td>

<a id="ac211c1a503d38d504c92b5f006240053a47aee8a3336612189e116839c9398aa3"></a>AUDIO_CODEC_PCMU

</td>
<td>4: PCMU</td>
</tr>
<tr>
<td>

<a id="ac211c1a503d38d504c92b5f006240053a0e153f963224879f02255a8e557bfeb5"></a>AUDIO_CODEC_G722

</td>
<td>5: G722</td>
</tr>
<tr>
<td>

<a id="ac211c1a503d38d504c92b5f006240053a9826001d5230eb1383e1af589ea4b972"></a>AUDIO_CODEC_AACLC

</td>
<td>8: AAC LC</td>
</tr>
<tr>
<td>

<a id="ac211c1a503d38d504c92b5f006240053a39d84162c35f3ab0be6fac022591bd2a"></a>AUDIO_CODEC_HEAAC

</td>
<td>9: HE AAC</td>
</tr>
<tr>
<td>

<a id="ac211c1a503d38d504c92b5f006240053a61b2cdb6ef05d8def8e35d61f443db33"></a>AUDIO_CODEC_HEAAC2

</td>
<td>11: HEAAC2</td>
</tr>
</tbody>
</DocsTable>

<a id="a5f78a8dc3552e4ec308270198dd49b55"></a>

### VIDEO_STREAM_TYPE [#video_stream_type]

<ApiSignature>

enum [agora::rtc::VIDEO_STREAM_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a5f78a8dc3552e4ec308270198dd49b55)

</ApiSignature>

视频流类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a5f78a8dc3552e4ec308270198dd49b55a115955aeb07c864335c1bf23ec59953e"></a>VIDEO_STREAM_HIGH

</td>
<td>0: 大流。分辨率和码率较高。</td>
</tr>
<tr>
<td>

<a id="a5f78a8dc3552e4ec308270198dd49b55a5e75ad3a4498bf5c2daafad6610a3e5a"></a>VIDEO_STREAM_LOW

</td>
<td>1: 小流。分辨率和码率较低。</td>
</tr>
</tbody>
</DocsTable>

<a id="a8f684b7ea22afd313ea9fbff6d6aea13"></a>

### VIDEO_MIRROR_MODE_TYPE [#video_mirror_mode_type]

<ApiSignature>

enum [agora::rtc::VIDEO_MIRROR_MODE_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a8f684b7ea22afd313ea9fbff6d6aea13)

</ApiSignature>

镜像模式类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a8f684b7ea22afd313ea9fbff6d6aea13a9e37327c3d25497dc587a63a28671f0f"></a>VIDEO_MIRROR_MODE_AUTO

</td>
<td>0：（默认）由 SDK 决定镜像模式。</td>
</tr>
<tr>
<td>

<a id="a8f684b7ea22afd313ea9fbff6d6aea13ada3518bf73757e866ebcac5e80e27e3f"></a>VIDEO_MIRROR_MODE_ENABLED

</td>
<td>1: 启用镜像模式。</td>
</tr>
<tr>
<td>

<a id="a8f684b7ea22afd313ea9fbff6d6aea13ae30d613a911b110e8628e9b0d28e9ac9"></a>VIDEO_MIRROR_MODE_DISABLED

</td>
<td>2: 关闭镜像模式。</td>
</tr>
</tbody>
</DocsTable>

<a id="a0ec618f678ca12272679cbb93e01f3f4"></a>

### SIMULCAST_STREAM_MODE [#simulcast_stream_mode]

<ApiSignature>

enum [agora::rtc::SIMULCAST_STREAM_MODE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a0ec618f678ca12272679cbb93e01f3f4)

</ApiSignature>

发送视频流的模式。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a0ec618f678ca12272679cbb93e01f3f4a6dd054127d354c2abd52a7636b2b9d94"></a>AUTO_SIMULCAST_STREAM

</td>
<td>-1：默认不发送小流，直至收到接收端发起的订阅小流申请时，自动切换为发送小流模式。</td>
</tr>
<tr>
<td>

<a id="a0ec618f678ca12272679cbb93e01f3f4a22ac2a70a5a84d804f505a7db38ee093"></a>DISABLE_SIMULCAST_STREAM

</td>
<td>0：始终不发送小流。</td>
</tr>
<tr>
<td>

<a id="a0ec618f678ca12272679cbb93e01f3f4a00d6c1355528b457298c7fa6bc4cb755"></a>ENABLE_SIMULCAST_STREAM

</td>
<td>1：始终发送小流。</td>
</tr>
</tbody>
</DocsTable>

<a id="ac6699b3c40e047af097d877115dde751"></a>

### VIDEO_SOURCE_TYPE [#video_source_type]

<ApiSignature>

enum [agora::rtc::VIDEO_SOURCE_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ac6699b3c40e047af097d877115dde751)

</ApiSignature>

视频源的类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a088a280c4204b82a8b459a81116a6d1c"></a>VIDEO_SOURCE_CAMERA_PRIMARY

</td>
<td>0：（默认）第一个摄像头。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a34ed3e8d6f90d64b327f890c690b62fd"></a>VIDEO_SOURCE_CAMERA

</td>
<td>0：摄像头。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a6cf51b1f6014ae5235e5cb06c0c94fe0"></a>VIDEO_SOURCE_CAMERA_SECONDARY

</td>
<td>1：第二个摄像头。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a3800c4e85a719f00a15a989cbccc4aa4"></a>VIDEO_SOURCE_SCREEN_PRIMARY

</td>
<td>2：第一个屏幕。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751acc0a885b0b273e2708e50f86b94142c9"></a>VIDEO_SOURCE_SCREEN

</td>
<td>2：屏幕。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751aa54842e7340f66b113f7a429fca36aeb"></a>VIDEO_SOURCE_SCREEN_SECONDARY

</td>
<td>3：第二个屏幕。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a215a20f135a19390876851a29762c96b"></a>VIDEO_SOURCE_CUSTOM

</td>
<td>4：自定义的视频源。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751abedaad87768634e870614424f3b74785"></a>VIDEO_SOURCE_MEDIA_PLAYER

</td>
<td>5：媒体播放器共享的视频源。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751af03455532348db7151b91e2faf67871a"></a>VIDEO_SOURCE_RTC_IMAGE_PNG

</td>
<td>6：视频源为 PNG 图片。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a17491d6725bfdb4735f18c5d86bd9fca"></a>VIDEO_SOURCE_RTC_IMAGE_JPEG

</td>
<td>7：视频源为 JPEG 图片。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a224314b533e8347d86e35bb10a4c2726"></a>VIDEO_SOURCE_RTC_IMAGE_GIF

</td>
<td>8：视频源为 GIF 图片。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751a57b4d782e7da427d3c17546ee92f20c4"></a>VIDEO_SOURCE_REMOTE

</td>
<td>9：视频源为网络获取的远端视频。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751aef414c00ce57b3278695b090ac4df9f9"></a>VIDEO_SOURCE_TRANSCODED

</td>
<td>10：转码后的视频源。</td>
</tr>
<tr>
<td>

<a id="ac6699b3c40e047af097d877115dde751ab2cafe4ce84ddeefb1c10ac8abaeff36"></a>VIDEO_SOURCE_UNKNOWN

</td>
<td>11：未知的视频源。</td>
</tr>
</tbody>
</DocsTable>

<a id="a42f167813e36b5c11a8a1c659b877080"></a>

### CLIENT_ROLE_TYPE [#client_role_type]

<ApiSignature>

enum [agora::rtc::CLIENT_ROLE_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a42f167813e36b5c11a8a1c659b877080)

</ApiSignature>

用户角色类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a42f167813e36b5c11a8a1c659b877080a8a1a7a863a7f1f1f23d300d59d719912"></a>CLIENT_ROLE_BROADCASTER

</td>
<td>1: 主播。主播可以同时发送和接收媒体流。</td>
</tr>
<tr>
<td>

<a id="a42f167813e36b5c11a8a1c659b877080a21c4eacfac7477cf9b061cebd7093d97"></a>CLIENT_ROLE_AUDIENCE

</td>
<td>2: 观众。观众只能接收媒体流。</td>
</tr>
</tbody>
</DocsTable>

<a id="ab8ebad21ea6a6b579c03f05c4533a071"></a>

### QUALITY_ADAPT_INDICATION [#quality_adapt_indication]

<ApiSignature>

enum [agora::rtc::QUALITY_ADAPT_INDICATION](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ab8ebad21ea6a6b579c03f05c4533a071)

</ApiSignature>

视频质量变化提示。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ab8ebad21ea6a6b579c03f05c4533a071a36d8846dfe311cc3aa7a4c21d1b09cf5"></a>ADAPT_NONE

</td>
<td>0：本地视频质量不变。</td>
</tr>
<tr>
<td>

<a id="ab8ebad21ea6a6b579c03f05c4533a071a3ea2884cacdfa1e8cebcf4f2a1b1de85"></a>ADAPT_UP_BANDWIDTH

</td>
<td>1：由于网络带宽增加导致质量提升。</td>
</tr>
<tr>
<td>

<a id="ab8ebad21ea6a6b579c03f05c4533a071a92869c78f5489738ea1413035c59c8b7"></a>ADAPT_DOWN_BANDWIDTH

</td>
<td>2：由于网络带宽降低导致质量下降。</td>
</tr>
</tbody>
</DocsTable>

<a id="a8d5b01851e8fcbee10e5bd85fb9bf15a"></a>

### EXPERIENCE_QUALITY_TYPE [#experience_quality_type]

<ApiSignature>

enum [agora::rtc::EXPERIENCE_QUALITY_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a8d5b01851e8fcbee10e5bd85fb9bf15a)

</ApiSignature>

接收远端音频时，本地用户的主观体验质量。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a8d5b01851e8fcbee10e5bd85fb9bf15aa2d970353462d66fab90095055a1f3062"></a>EXPERIENCE_QUALITY_GOOD

</td>
<td>0: 主观体验质量较好。</td>
</tr>
<tr>
<td>

<a id="a8d5b01851e8fcbee10e5bd85fb9bf15aa7570318e483039dfc47033eaf9e036c9"></a>EXPERIENCE_QUALITY_BAD

</td>
<td>1: 主观体验质量较差。</td>
</tr>
</tbody>
</DocsTable>

<a id="a830f382d595a185632d0fece36d67d54"></a>

### EXPERIENCE_POOR_REASON [#experience_poor_reason]

<ApiSignature>

enum [agora::rtc::EXPERIENCE_POOR_REASON](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a830f382d595a185632d0fece36d67d54)

</ApiSignature>

接收远端音频时，本地用户主观体验质量较差的原因。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a830f382d595a185632d0fece36d67d54a3a127af891654876ad34a2404d17a7fb"></a>EXPERIENCE_REASON_NONE

</td>
<td>0: 无原因，说明主观体验质量较好。</td>
</tr>
<tr>
<td>

<a id="a830f382d595a185632d0fece36d67d54afbefb5b8fc8ba61e934e3e4ffad472c0"></a>REMOTE_NETWORK_QUALITY_POOR

</td>
<td>1: 远端用户的网络较差。</td>
</tr>
<tr>
<td>

<a id="a830f382d595a185632d0fece36d67d54a2ce9dd01a723e103bd851dfb892a2892"></a>LOCAL_NETWORK_QUALITY_POOR

</td>
<td>2: 本地用户的网络较差。</td>
</tr>
<tr>
<td>

<a id="a830f382d595a185632d0fece36d67d54a634c8ded29dfafa8b41da9187daf5d9a"></a>WIRELESS_SIGNAL_POOR

</td>
<td>4: 本地用户的 Wi-Fi 或者移动数据网络信号弱。</td>
</tr>
<tr>
<td>

<a id="a830f382d595a185632d0fece36d67d54ab624ea30a5ec9a0ade1afcf03c886177"></a>WIFI_BLUETOOTH_COEXIST

</td>
<td>8: 本地用户同时开启 Wi-Fi 和蓝牙，二者信号互相干扰，导致音频传输质量下降。</td>
</tr>
</tbody>
</DocsTable>

<a id="a75448342947f6e98becc2b27d2edca55"></a>

### AUDIO_PROFILE_TYPE [#audio_profile_type]

<ApiSignature>

enum [agora::rtc::AUDIO_PROFILE_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a75448342947f6e98becc2b27d2edca55)

</ApiSignature>

音频属性。设置采样率，码率，编码模式和声道数。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55acd8fd9d26d8c8955376f9ff51274ca2b"></a>AUDIO_PROFILE_DEFAULT

</td>
<td>

0: 默认音频场景。

- 通信场景下：16 KHz 采样率，语音编码，单声道，编码码率最大值为 16 Kbps。
- 直播场景下：48 KHz 采样率，音乐编码，单声道，编码码率最大值为 64 Kbps。

</td>
</tr>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55affc1f92238b3aef72ed2b80401ed0551"></a>AUDIO_PROFILE_SPEECH_STANDARD

</td>
<td>1: 指定 32 KHz 采样率，语音编码，单声道，编码码率最大值为 18 Kbps。</td>
</tr>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55ae679e3ccbbae7bf1380d9cd81413db6c"></a>AUDIO_PROFILE_MUSIC_STANDARD

</td>
<td>2: 指定 48 KHz 采样率，音乐编码，单声道，编码码率最大值为 64 Kbps。</td>
</tr>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55a18087e125c075c85266716fc9bcf4c48"></a>AUDIO_PROFILE_MUSIC_STANDARD_STEREO

</td>
<td>3: 指定 48 KHz 采样率，音乐编码，双声道，编码码率最大值为 80 Kbps。</td>
</tr>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55a3cdc504b3107c07fc3f6da3aaa92e9d0"></a>AUDIO_PROFILE_MUSIC_HIGH_QUALITY

</td>
<td>4: 指定 48 KHz 采样率，音乐编码，单声道，编码码率最大值为 96 Kbps。</td>
</tr>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55aff92287ea621655559626dfae7478451"></a>AUDIO_PROFILE_MUSIC_HIGH_QUALITY_STEREO

</td>
<td>5: 指定 48 KHz 采样率，音乐编码，双声道，编码码率最大值为 128 Kbps。</td>
</tr>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55a2b957d65e55598c4f3a2a9ff0395d17d"></a>AUDIO_PROFILE_IOT

</td>
<td>6: 指定 16 kHz 采样率，语音编码，单声道，应用回声消除算法 AES。</td>
</tr>
<tr>
<td>

<a id="a75448342947f6e98becc2b27d2edca55abac03ea04a5bce04a83f608af8847c9b"></a>AUDIO_PROFILE_NUM

</td>
<td>枚举值边界。</td>
</tr>
</tbody>
</DocsTable>

<a id="a2c5708461a9e1568bbda636d95055533"></a>

### AUDIO_SCENARIO_TYPE [#audio_scenario_type]

<ApiSignature>

enum [agora::rtc::AUDIO_SCENARIO_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a2c5708461a9e1568bbda636d95055533)

</ApiSignature>

音频应用场景。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a2c5708461a9e1568bbda636d95055533afd3662c362a5497828550290ab003735"></a>AUDIO_SCENARIO_DEFAULT

</td>
<td>0: （默认）自动场景，根据用户角色和音频路由自动匹配合适的音质。</td>
</tr>
<tr>
<td>

<a id="a2c5708461a9e1568bbda636d95055533a42f87ca1c43185f9084cd0fa9808b9a9"></a>AUDIO_SCENARIO_GAME_STREAMING

</td>
<td>3: 高音质场景，适用于音乐为主的场景。</td>
</tr>
<tr>
<td>

<a id="a2c5708461a9e1568bbda636d95055533aec10020d50ff659b77ac160482228e42"></a>AUDIO_SCENARIO_CHATROOM

</td>
<td>5: 聊天室场景，适用于用户需要频繁上下麦的场景。该场景下，观众会收到申请麦克风权限的弹窗提示。</td>
</tr>
<tr>
<td>

<a id="a2c5708461a9e1568bbda636d95055533a8680bbc2f9d3247e4d65c202877eb5ee"></a>AUDIO_SCENARIO_CHORUS

</td>
<td>7: 合唱场景，适用于网络条件良好，要求极低延时的实时合唱场景。</td>
</tr>
<tr>
<td>

<a id="a2c5708461a9e1568bbda636d95055533a717eec01a97bcf9e8ec82266c5a2f3d5"></a>AUDIO_SCENARIO_MEETING

</td>
<td>8: 会议场景，适用于人声为主的多人会议。</td>
</tr>
<tr>
<td>

<a id="a2c5708461a9e1568bbda636d95055533a35d5c54e239a1f80d38fb1c4577f3da6"></a>AUDIO_SCENARIO_NUM

</td>
<td>枚举值边界。</td>
</tr>
</tbody>
</DocsTable>

<a id="a19311f858629420654fcc0da9d043332"></a>

### LOCAL_AUDIO_STREAM_STATE [#local_audio_stream_state]

<ApiSignature>

enum [agora::rtc::LOCAL_AUDIO_STREAM_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a19311f858629420654fcc0da9d043332)

</ApiSignature>

本地音频状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a19311f858629420654fcc0da9d043332ac3c41c909dcd344ace461c48788481ab"></a>LOCAL_AUDIO_STREAM_STATE_STOPPED

</td>
<td>0: 本地音频位于初始状态。</td>
</tr>
<tr>
<td>

<a id="a19311f858629420654fcc0da9d043332aa9157bed267eba92cfb6c2a3acb5a7e0"></a>LOCAL_AUDIO_STREAM_STATE_RECORDING

</td>
<td>1: 音频录制设备成功启动。</td>
</tr>
<tr>
<td>

<a id="a19311f858629420654fcc0da9d043332aec6af6a49b19d437d738a8f0721ae2c1"></a>LOCAL_AUDIO_STREAM_STATE_ENCODING

</td>
<td>2: 第一个音频帧成功完成编码。</td>
</tr>
<tr>
<td>

<a id="a19311f858629420654fcc0da9d043332a1f3ad0127796639401a7bb4193c96b67"></a>LOCAL_AUDIO_STREAM_STATE_FAILED

</td>
<td>3: 本地音频启动失败。</td>
</tr>
</tbody>
</DocsTable>

<a id="a3929991eea3a522dcbf6ac078810045e"></a>

### LOCAL_AUDIO_STREAM_ERROR [#local_audio_stream_error]

<ApiSignature>

enum [agora::rtc::LOCAL_AUDIO_STREAM_ERROR](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a3929991eea3a522dcbf6ac078810045e)

</ApiSignature>

本地音频失败的原因。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a3929991eea3a522dcbf6ac078810045eae885394c6686de5e5f02d3f9ff41f404"></a>LOCAL_AUDIO_STREAM_ERROR_OK

</td>
<td>0: 本地音频状态正常。</td>
</tr>
<tr>
<td>

<a id="a3929991eea3a522dcbf6ac078810045ea0a2a7f0a95512612ace909f32f0e6fa1"></a>LOCAL_AUDIO_STREAM_ERROR_FAILURE

</td>
<td>1: 原因未知。</td>
</tr>
<tr>
<td>

<a id="a3929991eea3a522dcbf6ac078810045eade3c7c2610610a823e17e3143b64671b"></a>LOCAL_AUDIO_STREAM_ERROR_DEVICE_NO_PERMISSION

</td>
<td>2: 没有权限使用本地音频设备。</td>
</tr>
<tr>
<td>

<a id="a3929991eea3a522dcbf6ac078810045ea18d5153634f36b31fa22cbd4af1ab9ee"></a>LOCAL_AUDIO_STREAM_ERROR_DEVICE_BUSY

</td>
<td>3: 麦克风被占用。</td>
</tr>
<tr>
<td>

<a id="a3929991eea3a522dcbf6ac078810045ead9325bf3dc67dcdceb37b2d5f4664905"></a>LOCAL_AUDIO_STREAM_ERROR_RECORD_FAILURE

</td>
<td>4: 本地音频录制失败。检查录制设备是否正常工作。</td>
</tr>
<tr>
<td>

<a id="a3929991eea3a522dcbf6ac078810045ea47e3c85eaebf952b4815cef4b20ff297"></a>LOCAL_AUDIO_STREAM_ERROR_ENCODE_FAILURE

</td>
<td>5: 本地音频编码失败。</td>
</tr>
</tbody>
</DocsTable>

<a id="a7c8ce313cb6ccb0d186953bd06e6200b"></a>

### LOCAL_VIDEO_STREAM_STATE [#local_video_stream_state]

<ApiSignature>

enum [agora::rtc::LOCAL_VIDEO_STREAM_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a7c8ce313cb6ccb0d186953bd06e6200b)

</ApiSignature>

本地视频状态类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a7c8ce313cb6ccb0d186953bd06e6200ba9bb52f743f03c961df2237cd72046a4f"></a>LOCAL_VIDEO_STREAM_STATE_STOPPED

</td>
<td>0: 初始状态。</td>
</tr>
<tr>
<td>

<a id="a7c8ce313cb6ccb0d186953bd06e6200bafe5af8aeff46879f3144ac03e6aa0757"></a>LOCAL_VIDEO_STREAM_STATE_CAPTURING

</td>
<td>1: 视频采集已开始。</td>
</tr>
<tr>
<td>

<a id="a7c8ce313cb6ccb0d186953bd06e6200ba2e843243500ed35448afb877e1c06032"></a>LOCAL_VIDEO_STREAM_STATE_ENCODING

</td>
<td>2: 第一个视频帧已编码。</td>
</tr>
<tr>
<td>

<a id="a7c8ce313cb6ccb0d186953bd06e6200ba456af207107500445138c5f35b3d938d"></a>LOCAL_VIDEO_STREAM_STATE_FAILED

</td>
<td>3: 本地视频发送失败。</td>
</tr>
</tbody>
</DocsTable>

<a id="aca8292c30c50a78f6fbd1ef1b264d842"></a>

### LOCAL_VIDEO_STREAM_ERROR [#local_video_stream_error]

<ApiSignature>

enum [agora::rtc::LOCAL_VIDEO_STREAM_ERROR](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#aca8292c30c50a78f6fbd1ef1b264d842)

</ApiSignature>

本地视频出错原因。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="aca8292c30c50a78f6fbd1ef1b264d842a2695a861e13d12ac54bb20d3d630311e"></a>LOCAL_VIDEO_STREAM_ERROR_OK

</td>
<td>0: 本地视频状态正常。</td>
</tr>
<tr>
<td>

<a id="aca8292c30c50a78f6fbd1ef1b264d842ab7dd59c52b4cb11b12c2db7597d63f66"></a>LOCAL_VIDEO_STREAM_ERROR_FAILURE

</td>
<td>1: 出错原因不明确。</td>
</tr>
<tr>
<td>

<a id="aca8292c30c50a78f6fbd1ef1b264d842a0f8ebaaffc51e8a9a1fbeac39715ad62"></a>LOCAL_VIDEO_STREAM_ERROR_DEVICE_NO_PERMISSION

</td>
<td>2: 没有权限启动本地视频采集设备。</td>
</tr>
<tr>
<td>

<a id="aca8292c30c50a78f6fbd1ef1b264d842ab2095d8de4bb63147b1e121c466e2eac"></a>LOCAL_VIDEO_STREAM_ERROR_DEVICE_BUSY

</td>
<td>3: 本地视频采集设备正在使用中。</td>
</tr>
<tr>
<td>

<a id="aca8292c30c50a78f6fbd1ef1b264d842a5e8d8b389aacc1732840973586baa286"></a>LOCAL_VIDEO_STREAM_ERROR_CAPTURE_FAILURE

</td>
<td>4: 本地视频采集失败，建议检查采集设备是否正常工作。</td>
</tr>
<tr>
<td>

<a id="aca8292c30c50a78f6fbd1ef1b264d842ad331f36475ad1f8617ad9e65fbf7ebfd"></a>LOCAL_VIDEO_STREAM_ERROR_ENCODE_FAILURE

</td>
<td>5: 本地视频编码失败。</td>
</tr>
</tbody>
</DocsTable>

<a id="aa83ef274510d1063e840d6104fd12516"></a>

### REMOTE_AUDIO_STATE [#remote_audio_state]

<ApiSignature>

enum [agora::rtc::REMOTE_AUDIO_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#aa83ef274510d1063e840d6104fd12516)

</ApiSignature>

远端音频流状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="aa83ef274510d1063e840d6104fd12516a7463dc6d26033cfacd12ffc39a7454d9"></a>REMOTE_AUDIO_STATE_STOPPED

</td>
<td>0：远端音频默认初始状态。在 `REMOTE_AUDIO_STATE_REASON_LOCAL_MUTED`、 `REMOTE_AUDIO_STATE_REASON_REMOTE_MUTED` 或 `REMOTE_AUDIO_STATE_REASON_REMOTE_OFFLINE` 的情况下，会报告该状态。</td>
</tr>
<tr>
<td>

<a id="aa83ef274510d1063e840d6104fd12516a4d808806be3f8a87886d26617b90f87a"></a>REMOTE_AUDIO_STATE_STARTING

</td>
<td>1: 本地用户已接收远端音频首包。</td>
</tr>
<tr>
<td>

<a id="aa83ef274510d1063e840d6104fd12516ae46f2eb53b7fc3b7f7cfb7d7fab4f75c"></a>REMOTE_AUDIO_STATE_DECODING

</td>
<td>2: 远端音频流正在解码，正常播放。在 `REMOTE_AUDIO_STATE_REASON_NETWORK_RECOVERY`、 `REMOTE_AUDIO_STATE_REASON_LOCAL_UNMUTED` 或 `REMOTE_AUDIO_STATE_REASON_REMOTE_UNMUTED` 的情况下， 会报告该状态。</td>
</tr>
<tr>
<td>

<a id="aa83ef274510d1063e840d6104fd12516ad2df06bc8d804962bc422c39f7729083"></a>REMOTE_AUDIO_STATE_FROZEN

</td>
<td>3: 远端音频流卡顿。在 `REMOTE_AUDIO_STATE_REASON_NETWORK_CONGESTION` 的情况下，会报告该状态。</td>
</tr>
<tr>
<td>

<a id="aa83ef274510d1063e840d6104fd12516a3d97dbd00fbac952acf11d2763a9d7e5"></a>REMOTE_AUDIO_STATE_FAILED

</td>
<td>4: 远端音频流播放失败。在 `REMOTE_AUDIO_STATE_REASON_INTERNAL` 的情况下，会报告该状态。</td>
</tr>
</tbody>
</DocsTable>

<a id="a532f4584f6ed5962012e1f08bef6f0fc"></a>

### REMOTE_AUDIO_STATE_REASON [#remote_audio_state_reason]

<ApiSignature>

enum [agora::rtc::REMOTE_AUDIO_STATE_REASON](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a532f4584f6ed5962012e1f08bef6f0fc)

</ApiSignature>

远端音频流状态切换原因。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fcacaa43c150ce1c677f2a51f6f2433096a"></a>REMOTE_AUDIO_REASON_INTERNAL

</td>
<td>0: 音频状态发生改变时，会报告该原因。</td>
</tr>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fca7f138c39f7319a6ba719ceb6f5eacba7"></a>REMOTE_AUDIO_REASON_NETWORK_CONGESTION

</td>
<td>1: 网络阻塞。</td>
</tr>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fcac2720abcfdb7bf6a6a8166abf515395b"></a>REMOTE_AUDIO_REASON_NETWORK_RECOVERY

</td>
<td>2: 网络恢复正常。</td>
</tr>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fca561a396c1f6d7adbbefe86c428683ad6"></a>REMOTE_AUDIO_REASON_LOCAL_MUTED

</td>
<td>3: 本地用户停止接收远端音频流或本地用户禁用音频模块。</td>
</tr>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fcac5ebd4f77fcf94b838e9d2da89b013e6"></a>REMOTE_AUDIO_REASON_LOCAL_UNMUTED

</td>
<td>4: 本地用户恢复接收远端音频流或本地用户启动音频模块。</td>
</tr>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fca54c8d889ed645500113fc18f876c5494"></a>REMOTE_AUDIO_REASON_REMOTE_MUTED

</td>
<td>5: 远端用户停止发送音频流或远端用户禁用音频模块。</td>
</tr>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fca0e898d0e3022385e6c9d185d73972c2f"></a>REMOTE_AUDIO_REASON_REMOTE_UNMUTED

</td>
<td>6: 远端用户恢复发送音频流或远端用户启用音频模块。</td>
</tr>
<tr>
<td>

<a id="a532f4584f6ed5962012e1f08bef6f0fca6f4851ce8d939dd587f0888b1d2a5fe9"></a>REMOTE_AUDIO_REASON_REMOTE_OFFLINE

</td>
<td>7: 远端用户离开频道。</td>
</tr>
</tbody>
</DocsTable>

<a id="a8098bde3bb614a7716d0f39105b8f1d8"></a>

### REMOTE_VIDEO_STATE [#remote_video_state]

<ApiSignature>

enum [agora::rtc::REMOTE_VIDEO_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a8098bde3bb614a7716d0f39105b8f1d8)

</ApiSignature>

远端视频流状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a8098bde3bb614a7716d0f39105b8f1d8afe59a97a2d92b043864ba01dfdf4d917"></a>REMOTE_VIDEO_STATE_STOPPED

</td>
<td>0: 远端视频默认初始状态。在 `REMOTE_VIDEO_STATE_REASON_LOCAL_MUTED`、`REMOTE_VIDEO_STATE_REASON_REMOTE_MUTED` 或 `REMOTE_VIDEO_STATE_REASON_REMOTE_OFFLINE` 的情况下，会报告该状态。</td>
</tr>
<tr>
<td>

<a id="a8098bde3bb614a7716d0f39105b8f1d8ad5d9ad6fe0d96c7ea7c65bf59c8c0e63"></a>REMOTE_VIDEO_STATE_STARTING

</td>
<td>1: 本地用户已接收远端视频首包。</td>
</tr>
<tr>
<td>

<a id="a8098bde3bb614a7716d0f39105b8f1d8a659462d41f13f53f3073eb1150a7435d"></a>REMOTE_VIDEO_STATE_DECODING

</td>
<td>2: 远端视频流正在解码，正常播放。 在 `REMOTE_VIDEO_STATE_REASON_NETWORK_RECOVERY`、`REMOTE_VIDEO_STATE_REASON_LOCAL_UNMUTED`、`REMOTE_VIDEO_STATE_REASON_REMOTE_UNMUTED` 或 `REMOTE_VIDEO_STATE_REASON_AUDIO_FALLBACK_RECOVERY` 的情况下， 会报告该状态。</td>
</tr>
<tr>
<td>

<a id="a8098bde3bb614a7716d0f39105b8f1d8ac9e6585199f84abcab1074adadf40634"></a>REMOTE_VIDEO_STATE_FROZEN

</td>
<td>3: 远端视频流卡顿。在 `REMOTE_VIDEO_STATE_REASON_NETWORK_CONGESTION` 或 `REMOTE_VIDEO_STATE_REASON_AUDIO_FALLBACK` 的情况下，会报告该状态。</td>
</tr>
<tr>
<td>

<a id="a8098bde3bb614a7716d0f39105b8f1d8a1ea1ebf82ddb1782b4259fbc2a5ea7c3"></a>REMOTE_VIDEO_STATE_FAILED

</td>
<td>4: 远端视频流播放失败。在 `REMOTE_VIDEO_STATE_REASON_INTERNAL` 的情况下，会报告该状态。</td>
</tr>
</tbody>
</DocsTable>

<a id="ae31fce5548860cb0a62e4c232fb18bff"></a>

### REMOTE_VIDEO_STATE_REASON [#remote_video_state_reason]

<ApiSignature>

enum [agora::rtc::REMOTE_VIDEO_STATE_REASON](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ae31fce5548860cb0a62e4c232fb18bff)

</ApiSignature>

远端视频流状态切换原因。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffaea26e05fcb8887e852058a1873680f8c"></a>REMOTE_VIDEO_STATE_REASON_INTERNAL

</td>
<td>0: 视频状态发生改变时，会报告该原因。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffa24ac73ce5bd6a277616710988066ff6a"></a>REMOTE_VIDEO_STATE_REASON_NETWORK_CONGESTION

</td>
<td>1: 网络阻塞。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffa8b1dbaba9e3aa75e8a76e93f21c5bbd4"></a>REMOTE_VIDEO_STATE_REASON_NETWORK_RECOVERY

</td>
<td>2: 网络恢复正常。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffae30b7689ceb3dcd01b3b8b3ad1a704f3"></a>REMOTE_VIDEO_STATE_REASON_LOCAL_MUTED

</td>
<td>3: 本地用户停止接收远端视频流或本地用户禁用视频模块。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffa62125754b06f30479a5721e222eef201"></a>REMOTE_VIDEO_STATE_REASON_LOCAL_UNMUTED

</td>
<td>4: 本地用户恢复接收远端视频流或本地用户启动视频模块。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffa513577953b31bbacde159cfd99198503"></a>REMOTE_VIDEO_STATE_REASON_REMOTE_MUTED

</td>
<td>5: 远端用户停止发送视频流或远端用户禁用视频模块。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffa3cd0f8dfa3229bebe1b7f5037a8ac703"></a>REMOTE_VIDEO_STATE_REASON_REMOTE_UNMUTED

</td>
<td>6: 远端用户恢复发送视频流或远端用户启用视频模块。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffa9bc22d0a122082c4662e2c155611f2a9"></a>REMOTE_VIDEO_STATE_REASON_REMOTE_OFFLINE

</td>
<td>7: 远端用户离开频道。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffa84ac2f44167080fca3ba872796ff66af"></a>REMOTE_VIDEO_STATE_REASON_AUDIO_FALLBACK

</td>
<td>8: 弱网情况下，远端音视频流回退为音频流。</td>
</tr>
<tr>
<td>

<a id="ae31fce5548860cb0a62e4c232fb18bffac2f84fb8b7ba73eb74f6bd9bf44f5baf"></a>REMOTE_VIDEO_STATE_REASON_AUDIO_FALLBACK_RECOVERY

</td>
<td>9: 网络情况改善时，远端音频流恢复为音视频流。</td>
</tr>
</tbody>
</DocsTable>

<a id="a986ba95b84f37af9ae5790dd90765baa"></a>

### REMOTE_VIDEO_DOWNSCALE_LEVEL [#remote_video_downscale_level]

<ApiSignature>

enum [agora::rtc::REMOTE_VIDEO_DOWNSCALE_LEVEL](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a986ba95b84f37af9ae5790dd90765baa)

</ApiSignature>

远端视频缩小级别。级别越高，缩小程度越高。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a986ba95b84f37af9ae5790dd90765baaa91573f6a364c510eae4652f1740b6ef5"></a>REMOTE_VIDEO_DOWNSCALE_LEVEL_NONE

</td>
<td>0：不缩小。</td>
</tr>
<tr>
<td>

<a id="a986ba95b84f37af9ae5790dd90765baaa0820f5c9d6855cadabd17a04ae7367b5"></a>REMOTE_VIDEO_DOWNSCALE_LEVEL_1

</td>
<td>1：级别 1。</td>
</tr>
<tr>
<td>

<a id="a986ba95b84f37af9ae5790dd90765baaaba8b193b56704d549f394765f01702db"></a>REMOTE_VIDEO_DOWNSCALE_LEVEL_2

</td>
<td>2：级别 2。</td>
</tr>
<tr>
<td>

<a id="a986ba95b84f37af9ae5790dd90765baaa380c2eabb7a34532f424c66267c76c48"></a>REMOTE_VIDEO_DOWNSCALE_LEVEL_3

</td>
<td>3：级别 3。</td>
</tr>
<tr>
<td>

<a id="a986ba95b84f37af9ae5790dd90765baaa54e9b9d729a5ef908f0f4e04dfb71673"></a>REMOTE_VIDEO_DOWNSCALE_LEVEL_4

</td>
<td>4：级别 4。</td>
</tr>
</tbody>
</DocsTable>

<a id="a430364c3f2cbf4419b898077cf6977f7"></a>

### CONNECTION_STATE_TYPE [#connection_state_type]

<ApiSignature>

enum [agora::rtc::CONNECTION_STATE_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a430364c3f2cbf4419b898077cf6977f7)

</ApiSignature>

网络连接状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a430364c3f2cbf4419b898077cf6977f7a335642f7cca4e7761ddbd0a722f6dd29"></a>CONNECTION_STATE_DISCONNECTED

</td>
<td>1: 网络连接断开。</td>
</tr>
<tr>
<td>

<a id="a430364c3f2cbf4419b898077cf6977f7a8d286796a07a1b7d25d871d859ff5727"></a>CONNECTION_STATE_CONNECTING

</td>
<td>2: 建立网络连接中。</td>
</tr>
<tr>
<td>

<a id="a430364c3f2cbf4419b898077cf6977f7ae42663fc1191d37b6648916134bc42ea"></a>CONNECTION_STATE_CONNECTED

</td>
<td>3: 网络已连接。</td>
</tr>
<tr>
<td>

<a id="a430364c3f2cbf4419b898077cf6977f7a7e870baf55d8bc02fc294ad0b3971d2d"></a>CONNECTION_STATE_RECONNECTING

</td>
<td>4: 重新建立网络连接中。</td>
</tr>
<tr>
<td>

<a id="a430364c3f2cbf4419b898077cf6977f7aaf1e40b56dd8162ae63b9d6fc0d88241"></a>CONNECTION_STATE_FAILED

</td>
<td>5: 网络连接失败。</td>
</tr>
</tbody>
</DocsTable>

<a id="aa6c9106e765c0ebb15be1b3e4e384f65"></a>

### LASTMILE_PROBE_RESULT_STATE [#lastmile_probe_result_state]

<ApiSignature>

enum [agora::rtc::LASTMILE_PROBE_RESULT_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#aa6c9106e765c0ebb15be1b3e4e384f65)

</ApiSignature>

Last mile 质量探测结果的状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="aa6c9106e765c0ebb15be1b3e4e384f65a2ad1e8c070b48edb9bf416da2b4b8436"></a>LASTMILE_PROBE_RESULT_COMPLETE

</td>
<td>1: 表示本次 last mile 质量探测的结果是完整的。</td>
</tr>
<tr>
<td>

<a id="aa6c9106e765c0ebb15be1b3e4e384f65a7c744e3a9a98a609d96fab9c66c90a5c"></a>LASTMILE_PROBE_RESULT_INCOMPLETE_NO_BWE

</td>
<td>2: 表示本次 last mile 质量探测未进行带宽预测，因此结果不完整。一个可能的原因是测试资源暂时受限。</td>
</tr>
<tr>
<td>

<a id="aa6c9106e765c0ebb15be1b3e4e384f65ae9ac0c1d564b1be9e5733ce22d3154af"></a>LASTMILE_PROBE_RESULT_UNAVAILABLE

</td>
<td>3: 未进行 last mile 质量探测。一个可能的原因是网络连接中断。</td>
</tr>
</tbody>
</DocsTable>

<a id="a329573b5363b2065b4069e5bf6013144"></a>

### CONNECTION_CHANGED_REASON_TYPE [#connection_changed_reason_type]

<ApiSignature>

enum [agora::rtc::CONNECTION_CHANGED_REASON_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a329573b5363b2065b4069e5bf6013144)

</ApiSignature>

连接状态变化原因。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a909210151e80a40412b33b7c65f657d5"></a>CONNECTION_CHANGED_CONNECTING

</td>
<td>0: 建立网络连接中。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a7db96919ed2935f5b2002183b1ed21eb"></a>CONNECTION_CHANGED_JOIN_SUCCESS

</td>
<td>1: 成功加入频道。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a861e516bece11ba81cf53be6c2c631b0"></a>CONNECTION_CHANGED_INTERRUPTED

</td>
<td>2: 网络连接中断。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a322a93479407c09f82189e13f6aa79a3"></a>CONNECTION_CHANGED_BANNED_BY_SERVER

</td>
<td>3: 网络连接被服务器禁止。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144ab450ea0fd2e115e3ff60cc5afca4a3a5"></a>CONNECTION_CHANGED_JOIN_FAILED

</td>
<td>4: 加入频道失败。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a87b7858350d388b2ad6a2c46fd803cbe"></a>CONNECTION_CHANGED_LEAVE_CHANNEL

</td>
<td>5: 离开频道。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144ae6f2f9c1a302c6df1c05d6fdd2cc3d8e"></a>CONNECTION_CHANGED_INVALID_APP_ID

</td>
<td>6: 不是有效的 APP ID。请更换有效的 APP ID 重新加入频道。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a7222d75a9cbd116cd16761953e65df3b"></a>CONNECTION_CHANGED_INVALID_CHANNEL_NAME

</td>
<td>7: 不是有效的频道名。请更换有效的频道名重新加入频道。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a26ab3e648572bcf8bdd43d036aba3ec8"></a>CONNECTION_CHANGED_INVALID_TOKEN

</td>
<td>

8: 生成的 Token 无效。一般有以下原因：

- 在控制台上启用了 App Certificate，但加入频道未使用 Token。当启用了 App Certificate，必须使用 Token。
- 在调用 `connect` 加入频道时指定的 uid 与生成 Token 时传入的 uid 不一致。

</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144ac8493348234ccea33ac7e61ad268fe60"></a>CONNECTION_CHANGED_TOKEN_EXPIRED

</td>
<td>9: 生成的 Token 无效。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144ae0a9bf5f38d1828a96682e6678ff8c16"></a>CONNECTION_CHANGED_REJECTED_BY_SERVER

</td>
<td>10: 此用户被服务器禁止。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a95d29853df095ef245640e6b3d5e744a"></a>CONNECTION_CHANGED_SETTING_PROXY_SERVER

</td>
<td>11: 由于设置了代理服务器，SDK 尝试重连。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144abf908a9040ed3c9dc19ea3bd0036498b"></a>CONNECTION_CHANGED_RENEW_TOKEN

</td>
<td>12: 更新 Token 引起网络连接状态改变。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a9eb64c9200bbf61d9a4cb9e5371ebe0a"></a>CONNECTION_CHANGED_CLIENT_IP_ADDRESS_CHANGED

</td>
<td>13: 客户端 IP 地址变更，可能是由于网络类型，或网络运营商的 IP 或端口发生改变引起。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144acf412770f5052abd4f8d11ce52e1e3c3"></a>CONNECTION_CHANGED_KEEP_ALIVE_TIMEOUT

</td>
<td>14: SDK 和服务器连接保活超时，进入自动重连状态。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a48a6b0b0a23447a63143f94d0623b32c"></a>CONNECTION_CHANGED_REJOIN_SUCCESS

</td>
<td>15: 重新加入频道成功。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a9df6b7fcbba2d97e407c90a20988b76b"></a>CONNECTION_CHANGED_LOST

</td>
<td>16: SDK 和服务器失去连接。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144a4c2e2aa3bea1920093387fbaba9ed995"></a>CONNECTION_CHANGED_ECHO_TEST

</td>
<td>17: 连接状态变化由回声测试引起。</td>
</tr>
<tr>
<td>

<a id="a329573b5363b2065b4069e5bf6013144afdd77619ace4a8b364d5d0365ce755fa"></a>CONNECTION_CHANGED_CLIENT_IP_ADDRESS_CHANGED_BY_USER

</td>
<td>18: 用户更改了本地 IP 地址。</td>
</tr>
</tbody>
</DocsTable>

<a id="ab5e06b511f978f1a997008401da46505"></a>

### NETWORK_TYPE [#network_type]

<ApiSignature>

enum [agora::rtc::NETWORK_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ab5e06b511f978f1a997008401da46505)

</ApiSignature>

网络连接类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ab5e06b511f978f1a997008401da46505aaffd83f62604659b799989fc9755d773"></a>NETWORK_TYPE_UNKNOWN

</td>
<td>-1: 网络连接类型未知。</td>
</tr>
<tr>
<td>

<a id="ab5e06b511f978f1a997008401da46505a088190434b4a1271f4e5849cd41fc9fe"></a>NETWORK_TYPE_DISCONNECTED

</td>
<td>0: 网络连接已断开。</td>
</tr>
<tr>
<td>

<a id="ab5e06b511f978f1a997008401da46505abc2d98d2aa184f7766cc1d480b0302b3"></a>NETWORK_TYPE_LAN

</td>
<td>1: 网络类型为 LAN。</td>
</tr>
<tr>
<td>

<a id="ab5e06b511f978f1a997008401da46505abf47c9dede3e20c97f8d4c8e2050c4df"></a>NETWORK_TYPE_WIFI

</td>
<td>2: 网络类型为 Wi-Fi(包含热点）。</td>
</tr>
<tr>
<td>

<a id="ab5e06b511f978f1a997008401da46505ac93cdd7ba1c6004cd959a407bb9aaf0b"></a>NETWORK_TYPE_MOBILE_2G

</td>
<td>3: 网络类型为 2G 移动网络。</td>
</tr>
<tr>
<td>

<a id="ab5e06b511f978f1a997008401da46505a3f70717344b70437028cb9519ec07900"></a>NETWORK_TYPE_MOBILE_3G

</td>
<td>4: 网络类型为 3G 移动网络。</td>
</tr>
<tr>
<td>

<a id="ab5e06b511f978f1a997008401da46505a748a1c812bf1a7026aeca60322e0c126"></a>NETWORK_TYPE_MOBILE_4G

</td>
<td>5: 网络类型为 4G 移动网络。</td>
</tr>
</tbody>
</DocsTable>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5e"></a>

### AREA_CODE [#area_code]

<ApiSignature>

enum [agora::rtc::AREA_CODE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a85a66bc360e0d01a3f675c6a0fe95f5e)

</ApiSignature>

访问区域。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5eaf8e2d0900a4543fab82c7dc0b0074c35"></a>AREA_CODE_CN

</td>
<td>0x00000001：中国大陆。</td>
</tr>
<tr>
<td>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5ea69812bc2f9cccfac8cc34654ef159d11"></a>AREA_CODE_NA

</td>
<td>0x00000002：北美区域。</td>
</tr>
<tr>
<td>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5eaa47e5e2c0fe01fdec041bfe24fc12f0d"></a>AREA_CODE_EU

</td>
<td>0x00000004：欧洲区域。</td>
</tr>
<tr>
<td>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5ea8168957c370c6582c6c4fb75122e76b4"></a>AREA_CODE_AS

</td>
<td>0x00000008：除中国大陆以外的亚洲区域。</td>
</tr>
<tr>
<td>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5ead20308fc6f76ad911a42fb42fb678721"></a>AREA_CODE_JP

</td>
<td>0x00000010：日本。</td>
</tr>
<tr>
<td>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5eadd5d950a7dd5cc79b631ca836bdadf74"></a>AREA_CODE_IN

</td>
<td>0x00000020：印度。</td>
</tr>
<tr>
<td>

<a id="a85a66bc360e0d01a3f675c6a0fe95f5ead4bbb5e676a198ab727fb7e432111a2f"></a>AREA_CODE_GLOB

</td>
<td>0xFFFFFFFF：（默认）全球。</td>
</tr>
</tbody>
</DocsTable>

<a id="a906cebebbabf534c86ca71de0d1a4cf0"></a>

### ENCRYPTION_MODE [#encryption_mode]

<ApiSignature>

enum [agora::rtc::ENCRYPTION_MODE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a906cebebbabf534c86ca71de0d1a4cf0)

</ApiSignature>

内置加密模式。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a906cebebbabf534c86ca71de0d1a4cf0aa789ba9768f5f542f163c6460da7f365"></a>SM4_128_ECB

</td>
<td>4: 128-bit SM4 加密，ECB 模式。</td>
</tr>
</tbody>
</DocsTable>

<a id="a32a0270f2e3dab57953457ac1871b521"></a>

### ENCRYPTION_ERROR_TYPE [#encryption_error_type]

<ApiSignature>

enum [agora::rtc::ENCRYPTION_ERROR_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a32a0270f2e3dab57953457ac1871b521)

</ApiSignature>

内置加密的错误类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a32a0270f2e3dab57953457ac1871b521a441bf6a89ab42ecef6ae28949ea0435d"></a>ENCRYPTION_ERROR_INTERNAL_FAILURE

</td>
<td>0：内部原因。</td>
</tr>
<tr>
<td>

<a id="a32a0270f2e3dab57953457ac1871b521a337a35a9e01622a0d2a17b6e3f3e185b"></a>ENCRYPTION_ERROR_DECRYPTION_FAILURE

</td>
<td>1：解密错误。请确保接收端和发送端使用的加密模式或密钥一致。</td>
</tr>
<tr>
<td>

<a id="a32a0270f2e3dab57953457ac1871b521a24eaecae54c5ec0fc7cc505f5339afae"></a>ENCRYPTION_ERROR_ENCRYPTION_FAILURE

</td>
<td>2：加密错误。</td>
</tr>
</tbody>
</DocsTable>

<a id="a895ba93435851fd5ddbccd92e6d5356f"></a>

### MAX_USER_ACCOUNT_LENGTH_TYPE [#max_user_account_length_type]

<ApiSignature>

enum [agora::rtc::MAX_USER_ACCOUNT_LENGTH_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a895ba93435851fd5ddbccd92e6d5356f)

</ApiSignature>

user account 的最大长度。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a895ba93435851fd5ddbccd92e6d5356fa8a980d28f1c8c8e67300b430d18853f8"></a>MAX_USER_ACCOUNT_LENGTH

</td>
<td>256：user account 的最大长度（字节）。</td>
</tr>
</tbody>
</DocsTable>

<a id="ac405a073458682fd6464c82d49fece3c"></a>

### STREAM_SUBSCRIBE_STATE [#stream_subscribe_state]

<ApiSignature>

enum [agora::rtc::STREAM_SUBSCRIBE_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ac405a073458682fd6464c82d49fece3c)

</ApiSignature>

流订阅状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ac405a073458682fd6464c82d49fece3ca1e7316c35ab5c6854892582cc7967773"></a>SUB_STATE_IDLE

</td>
<td>0：加入频道后的初始订阅状态。</td>
</tr>
<tr>
<td>

<a id="ac405a073458682fd6464c82d49fece3ca6678ddfda9aece5abc6feb438d1d528d"></a>SUB_STATE_NO_SUBSCRIBED

</td>
<td>1：订阅失败。</td>
</tr>
<tr>
<td>

<a id="ac405a073458682fd6464c82d49fece3cace29d3c4aeb9206e71426d672ea7d963"></a>SUB_STATE_SUBSCRIBING

</td>
<td>2：正在订阅。</td>
</tr>
<tr>
<td>

<a id="ac405a073458682fd6464c82d49fece3cae4f929d7bd7112a7db7a8053581daecc"></a>SUB_STATE_SUBSCRIBED

</td>
<td>3：收到了远端流，订阅成功。</td>
</tr>
</tbody>
</DocsTable>

<a id="a58eeb8b495ca1c91d38785f064132537"></a>

### STREAM_PUBLISH_STATE [#stream_publish_state]

<ApiSignature>

enum [agora::rtc::STREAM_PUBLISH_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a58eeb8b495ca1c91d38785f064132537)

</ApiSignature>

流发布状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a58eeb8b495ca1c91d38785f064132537a14e3e6abd2239fe4ba1098fdfb4693c0"></a>PUB_STATE_IDLE

</td>
<td>0: 加入频道后的初始发布状态。</td>
</tr>
<tr>
<td>

<a id="a58eeb8b495ca1c91d38785f064132537a989dfdb24e7c2a5533dcdca3549629b2"></a>PUB_STATE_NO_PUBLISHED

</td>
<td>1: 发布失败。</td>
</tr>
<tr>
<td>

<a id="a58eeb8b495ca1c91d38785f064132537a926fbe7ef2663c708ac04cb0315a5745"></a>PUB_STATE_PUBLISHING

</td>
<td>2: 正在发布。</td>
</tr>
<tr>
<td>

<a id="a58eeb8b495ca1c91d38785f064132537a156bc733b29c56ffacae478f5f06d868"></a>PUB_STATE_PUBLISHED

</td>
<td>3: 发布成功。</td>
</tr>
</tbody>
</DocsTable>

<a id="a54de466c4f3f991c714bb5719d706b63"></a>

### TCcMode [#tccmode]

<ApiSignature>

enum [agora::rtc::TCcMode](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a54de466c4f3f991c714bb5719d706b63)

</ApiSignature>

阻塞控制模块选项。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a54de466c4f3f991c714bb5719d706b63aef79c253b99faa4f9a41cfa73a84a74f"></a>CC_ENABLED

</td>
<td>0：开启阻塞控制模块。</td>
</tr>
<tr>
<td>

<a id="a54de466c4f3f991c714bb5719d706b63ad4a94566cadf162aa667e0923a7697de"></a>CC_DISABLED

</td>
<td>1：关闭阻塞控制模块。</td>
</tr>
</tbody>
</DocsTable>

<a id="a74143af8b2847d195090020877e7369d"></a>

### BYTES_PER_SAMPLE [#bytes_per_sample]

<ApiSignature>

enum [agora::rtc::BYTES_PER_SAMPLE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a74143af8b2847d195090020877e7369d)

</ApiSignature>

每个样本的字节数。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a74143af8b2847d195090020877e7369da2ac2866da3a1e71f529fa2aa06eab97d"></a>TWO_BYTES_PER_SAMPLE

</td>
<td>2：每个样本两个字节。</td>
</tr>
</tbody>
</DocsTable>

<a id="ae5df06fc9c5b15135e22047c01e565bb"></a>

### RAW_AUDIO_FRAME_OP_MODE_TYPE [#raw_audio_frame_op_mode_type]

<ApiSignature>

enum [agora::rtc::RAW_AUDIO_FRAME_OP_MODE_TYPE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ae5df06fc9c5b15135e22047c01e565bb)

</ApiSignature>

`onRecordAudioFrame` 或 `onPlaybackAudioFrame` 回调中返回的音频数据的使用模式。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ae5df06fc9c5b15135e22047c01e565bbac46b5a2a6a1bcf560cdd0cad3c888d52"></a>RAW_AUDIO_FRAME_OP_MODE_READ_ONLY

</td>
<td>0: 只读模式，用户仅从 AudioFrame 获取原始数据，不作任何修改。</td>
</tr>
<tr>
<td>

<a id="ae5df06fc9c5b15135e22047c01e565bba981a8e6434a19c97343ffec38bf2e31a"></a>RAW_AUDIO_FRAME_OP_MODE_READ_WRITE

</td>
<td>2: 读写模式, 用户从 AudioFrame 获取并修改数据，并返回给 SDK 进行编码传输。</td>
</tr>
</tbody>
</DocsTable>

<a id="aff7596486950cd8ca8a3010d8c8710de"></a>

### RTMP_CONNECTION_ERROR [#rtmp_connection_error]

<ApiSignature>

enum [agora::rtc::RTMP_CONNECTION_ERROR](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#aff7596486950cd8ca8a3010d8c8710de)

</ApiSignature>

推流错误信息。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="aff7596486950cd8ca8a3010d8c8710dea9487ca7eea78822013083f643585e994"></a>RTMP_CONNECTION_ERR_OK

</td>
<td>0: 推流成功。</td>
</tr>
<tr>
<td>

<a id="aff7596486950cd8ca8a3010d8c8710deabdce99809b2f603d2c389b86a6ffd81d"></a>RTMP_CONNECTION_ERR_FAILED

</td>
<td>1: 一般性错误。</td>
</tr>
<tr>
<td>

<a id="aff7596486950cd8ca8a3010d8c8710dea8071775e91d6654350fc0e5fe7636d70"></a>RTMP_CONNECTION_ERR_INVALID_URL

</td>
<td>2: 推流 URL 无效。请检查输入的 URL 是否正确。</td>
</tr>
<tr>
<td>

<a id="aff7596486950cd8ca8a3010d8c8710dea3208d528c68c666efbcc599166c5467e"></a>RTMP_CONNECTION_ERR_BAD_NAME

</td>
<td>3: 该推流 URL 已用于推流。如果你想开始新的推流，请使用新的推流 URL。</td>
</tr>
</tbody>
</DocsTable>

<a id="a843a00f1c45fdfe18856a8f835018681"></a>

### RTMP_CONNECTION_STATE [#rtmp_connection_state]

<ApiSignature>

enum [agora::rtc::RTMP_CONNECTION_STATE](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a843a00f1c45fdfe18856a8f835018681)

</ApiSignature>

SDK 与 CDN 的连接状态。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a843a00f1c45fdfe18856a8f835018681a1e98a9b3e2100a99833d45d3f95c7728"></a>STATE_DISCONNECTED

</td>
<td>

1: SDK 与 CDN 断开连接。

以下操作会让 SDK 进入该状态：

- 调用 [createRtmpConnection](/zh-CN/api-reference/rtc-server-sdk/cpp/classagora-1-1base-1-1-i-agora-service#adae5bb15639f9559a1399082590955e5)，即 SDK 与 CDN 的初始连接状态。
- 调用 [disconnect](/zh-CN/api-reference/rtc-server-sdk/cpp/classagora-1-1rtc-1-1-i-rtmp-connection#ac3fcd6d1efd903f1bb75797fb709584e)。

</td>
</tr>
<tr>
<td>

<a id="a843a00f1c45fdfe18856a8f835018681a88f854c4436729950e18c291c8c19b6d"></a>STATE_CONNECTING

</td>
<td>

2: SDK 正在连接 CDN。

调用 [connect](/zh-CN/api-reference/rtc-server-sdk/cpp/classagora-1-1rtc-1-1-i-rtmp-connection#a5e89428056585b3b0643af03ff197ec4) 连接 CDN 的过程中，SDK 会进入该状态。

</td>
</tr>
<tr>
<td>

<a id="a843a00f1c45fdfe18856a8f835018681af8ba2691700e27ae350207c48b4ec1df"></a>STATE_CONNECTED

</td>
<td>

3: SDK 已连接 CDN。

调用 [connect](/zh-CN/api-reference/rtc-server-sdk/cpp/classagora-1-1rtc-1-1-i-rtmp-connection#a5e89428056585b3b0643af03ff197ec4) 成功连接 CDN 时，SDK 会进入该状态， 你可以开始向 CDN 推流。

</td>
</tr>
<tr>
<td>

<a id="a843a00f1c45fdfe18856a8f835018681aa0b16717707e51c789610f80d3c6f059"></a>STATE_RECONNECTING

</td>
<td>

4: SDK 正在重新连接 CDN。

在弱网环境或用户切换网络类型等情况下，如果 SDK 与 CDN 断开连接，SDK 会尝试重新连接 CDN 并进入该状态。

</td>
</tr>
<tr>
<td>

<a id="a843a00f1c45fdfe18856a8f835018681a2d592cdb8de205cec41e5eb702f4431c"></a>STATE_FAILED

</td>
<td>

5: SDK 连接 CDN 失败。

以下情况会让 SDK 进入该状态：

- 调用 [connect](/zh-CN/api-reference/rtc-server-sdk/cpp/classagora-1-1rtc-1-1-i-rtmp-connection#a5e89428056585b3b0643af03ff197ec4) 连接 CDN 失败时。
- 在弱网环境或用户切换网络类型等情况下，SDK 重新连接 CDN 失败时。

该状态下，如需连接 CDN，你需要先调用 [disconnect](/zh-CN/api-reference/rtc-server-sdk/cpp/classagora-1-1rtc-1-1-i-rtmp-connection#ac3fcd6d1efd903f1bb75797fb709584e) 断开连接， 再调用 [connect](/zh-CN/api-reference/rtc-server-sdk/cpp/classagora-1-1rtc-1-1-i-rtmp-connection#a5e89428056585b3b0643af03ff197ec4)。

</td>
</tr>
<tr>
<td>

<a id="a843a00f1c45fdfe18856a8f835018681a3941ce0aa3e7b73b3686a94d5804e4b5"></a>STATE_RECONNECTED

</td>
<td>

6: SDK 已重新连接 CDN。

在弱网环境或用户切换网络类型等情况下，如果 SDK 与 CDN 断开连接，则 SDK 重新连接 CDN 成功时会进入该状态。 你可以继续向 CDN 推流。

</td>
</tr>
</tbody>
</DocsTable>

<a id="ae1713f658284be303aaa022bcf018d47"></a>

### PublishAudioError [#publishaudioerror]

<ApiSignature>

enum [agora::rtc::PublishAudioError](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ae1713f658284be303aaa022bcf018d47)

</ApiSignature>

推送音频帧失败的错误码。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ae1713f658284be303aaa022bcf018d47a8f591dd20b09edddde423f6516049f83"></a>PUBLISH_AUDIO_ERR_OK

</td>
<td>0: 推送成功。</td>
</tr>
<tr>
<td>

<a id="ae1713f658284be303aaa022bcf018d47aaae115bb328bc08ac627da5da9b64ae5"></a>PUBLISH_AUDIO_ERR_FAILED

</td>
<td>1: 一般性错误。</td>
</tr>
</tbody>
</DocsTable>

<a id="a68e2825c220df8afbe45a98f59ccd63e"></a>

### PublishVideoError [#publishvideoerror]

<ApiSignature>

enum [agora::rtc::PublishVideoError](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a68e2825c220df8afbe45a98f59ccd63e)

</ApiSignature>

推送视频帧失败的错误码。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a68e2825c220df8afbe45a98f59ccd63ead4f8e8d4c95b080ebe57315470de4918"></a>PUBLISH_VIDEO_ERR_OK

</td>
<td>0: 推送成功。</td>
</tr>
<tr>
<td>

<a id="a68e2825c220df8afbe45a98f59ccd63eab7ce18174ee9b15caa9d0c60fc93b726"></a>PUBLISH_VIDEO_ERR_FAILED

</td>
<td>1: 一般性错误。</td>
</tr>
</tbody>
</DocsTable>

<a id="a2bb24f13233850a63fb152366902bd75"></a>

### ImageType [#imagetype]

<ApiSignature>

enum [agora::rtc::ImageType](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a2bb24f13233850a63fb152366902bd75)

</ApiSignature>

图像类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a2bb24f13233850a63fb152366902bd75a81830984dc6493ee9dc1f20cfecab173"></a>kPng

</td>
<td>PNG。</td>
</tr>
<tr>
<td>

<a id="a2bb24f13233850a63fb152366902bd75ab5257456edaf82872832b2c76194b8b3"></a>kJpeg

</td>
<td>JPEG。</td>
</tr>
<tr>
<td>

<a id="a2bb24f13233850a63fb152366902bd75a99b1da8bf6dc1d32ff098843d3049576"></a>kGif

</td>
<td>Gif。</td>
</tr>
</tbody>
</DocsTable>

<a id="ac7c53aef1d848fde23b24e9c9e14a26d"></a>

### StreamLayerIndexInternal [#streamlayerindexinternal]

<ApiSignature>

enum [agora::rtc::StreamLayerIndexInternal](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#ac7c53aef1d848fde23b24e9c9e14a26d)

</ApiSignature>

定义 YUV 视频流的索引，用于标识不同的流。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26daee8d44f729c22d7c6773ee56927dd0f8"></a>STREAM_LAYER_1

</td>
<td>`1`: 第 1 路流。</td>
</tr>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26da4aeab168f90bd1d68e2c24cb4350ab39"></a>STREAM_LAYER_2

</td>
<td>`2`: 第 2 路流。</td>
</tr>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26da8d773251752a80df0eb8aa3dad93b457"></a>STREAM_LAYER_3

</td>
<td>`3`: 第 3 路流。</td>
</tr>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26daedafa3ffd189ca1d2c272a6c65cd2d52"></a>STREAM_LAYER_4

</td>
<td>`4`: 第 4 路流。</td>
</tr>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26daf24d21dd50966a23f757a1e5902bb4c9"></a>STREAM_LAYER_5

</td>
<td>`5`: 第 5 路流。</td>
</tr>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26da0d0c04aba908347fa0161272524bc8c0"></a>STREAM_LAYER_6

</td>
<td>`6`: 第 6 路流。</td>
</tr>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26da9530b8403f1b34e408ef1a91d43657a7"></a>STREAM_LOW

</td>
<td>`7`: 视频小流。</td>
</tr>
<tr>
<td>

<a id="ac7c53aef1d848fde23b24e9c9e14a26da06c1204fcdf9fc528f81f6663da31343"></a>STREAM_LAYER_COUNT_MAX

</td>
<td>`8`: 枚举值边界。</td>
</tr>
</tbody>
</DocsTable>

<a id="a1a5e96c615b82373b20c842f8b20ccf9"></a>

### VideoTrackType [#videotracktype]

<ApiSignature>

enum [agora::rtc::VideoTrackType](/zh-CN/api-reference/rtc-server-sdk/cpp/namespaceagora-1-1rtc#a1a5e96c615b82373b20c842f8b20ccf9)

</ApiSignature>

视频轨道类型。

<DocsTable>
<thead>
<tr>
<th colSpan={2} scope="colgroup">枚举值</th>
</tr>
</thead>
<tbody>
<tr>
<td>

<a id="a1a5e96c615b82373b20c842f8b20ccf9a8d3e687b87c6008d6b856e8781580c3a"></a>LOCAL_VIDEO_TRACK

</td>
<td>本地视频轨道。</td>
</tr>
<tr>
<td>

<a id="a1a5e96c615b82373b20c842f8b20ccf9a3d199461a405a1ec0a3f5908eb518438"></a>REMOTE_VIDEO_TRACK

</td>
<td>远端视频轨道。</td>
</tr>
</tbody>
</DocsTable>

## 变量说明 [#变量说明]

<a id="aa3b9a29c1e9893671d0ca8fe05c7b302"></a>

### STANDARD_BITRATE [#standard_bitrate]

<ApiSignature>

const int agora::rtc::STANDARD_BITRATE = 0

</ApiSignature>

(推荐) 标准码率模式。该模式下，视频的码率是基准码率的两倍。

<a id="a4e18b18d956926c9c9c647d6ce5f1542"></a>

### COMPATIBLE_BITRATE [#compatible_bitrate]

<ApiSignature>

const int agora::rtc::COMPATIBLE_BITRATE = -1

</ApiSignature>

适配码率模式。该模式下，视频码率与基准码率一致。直播时如果选择该模式，视频帧率可能会低于设置的值。

<a id="af0e8e50f05a368140f51ab0b899f0833"></a>

### DEFAULT_CONNECTION_ID [#default_connection_id]

<ApiSignature labels="static">

const unsigned int agora::rtc::DEFAULT_CONNECTION_ID = 0

</ApiSignature>

<a id="abaad7ca107078a076b2543a6c13fcec7"></a>

### DUMMY_CONNECTION_ID [#dummy_connection_id]

<ApiSignature labels="static">

const unsigned int agora::rtc::DUMMY_CONNECTION_ID =(std::numeric_limits&lt;unsigned int&gt;::max)()

</ApiSignature>