# Agora SEI information (/en/realtime-media/media-push/reference/sei-information) > For AI agents: see the complete documentation index at [llms.txt](/llms.txt). By default, Agora adds the encoding information of the current video to the transcoded H264/H265 SEI (Supplemental Enhancement Information) during Media Push. The encoding information is a JSON string. The following is the sample code: ```json { "canvas": { "w": 640, "h": 360, "bgnd": "#000000" }, "regions": [ { "uid": 1, "alpha": 1.0, "zorder": 1, "volume": 50, "x": 0, "y": 0, "w": 320, "h": 360 }, { "uid": 2, "alpha": 1.0, "zOrder": 1, "volume": 89, "x": 320, "y": 0, "w": 320, "h": 360 } ], "ver": "20190611", "ts": 1535385600000, "app_data": "" } ``` The definition of the parameters: | Parameter | Description | | ---------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `canvas` | The canvas information. It contains the following properties:- `w`: Width (pixel) of the canvas. It corresponds to the `width` member in the `LiveTranscoding` class. - `h`: Height (pixel) of the canvas. It corresponds to the `height` member in the `LiveTranscoding` class. - `bgnd`: The background color (RGB) of the canvas, represented by a hexademical string. It corresponds to the `backgoundColor` member in the `LiveTranscoding` class. | | `regions` | The layout information of the host. It corresponds to the `transcodingUsers` member in the `LiveTranscoding` class. It contains the following properties:- `suid`: (**Optional**)The string user account of the host in this region. This parameter applies to use-cases where string user accounts are used to identify the host. - `uid`: UID of the host in this region. It corresponds to the `uid` member in the `TranscodingUser` class. - `alpha`: The transparency of the video frame of the host. The value range is \[0.0, 1.0]. It corresponds to the `alpha` member in `TranscodingUser` . - `zorder`: The layout position of the video frame of the host. The value range is \[0, 100]. It corresponds to the `zOrder` member in `TranscodingUser`. - `volume`: The volume (dB) of the host. The value range is \[0, 100]. - `x`: The horizontal position of the video frame of the broadacaster from the top left corner of the Media Push. It corresponds to the `x` member in `TranscodingUser`. - `y`: The vertical position of the video frame of the host from the top left corner of the Media Push. It corresponds to the `y` member in `TranscodingUser`. - `w`: Width (pixel) of the video frame of the host. It corresponds to the `width` member in `TranscodingUser`. - `h`: Height (pixel) of the video frame of the host. It corresponds to the `height` member in `TranscodingUser`. | | `ver` | The version of the SEI protocol. The current version is 20190611. | | `ts` | Timestamp (ms) of the current encoding information. | | `app_data` | Extra user-defined information. It corresponds to the `transcodingExtraInfo` member in the `LiveTranscoding` class. | ### The structure of SEI [#the-structure-of-sei] The SEI information is as follows: ```text 0000 0664bd7b 22617070 5f646174 61223a22 .d.{"app_data":" 0010 222c2263 616e7661 73223a7b 2262676e ","canvas":{"bgn 0020 64223a22 23666666 66666622 2c226822 d":"#ffffff","h" 0030 3a363430 2c227722 3a333630 7d2c2272 :640,"w":360},"r 0040 6567696f 6e73223a 5b7b2261 6c706861 egions":[{"alpha 0050 223a3235 352c2268 223a3634 302c2275 ":255,"h":640,"u 0060 6964223a 33313031 32373137 39312c22 id":3101271791," 0070 766f6c75 6d65223a 32382c22 77223a33 volume":28,"w":3 0080 36302c22 78223a30 2c227922 3a302c22 60,"x":0,"y":0," 0090 7a6f7264 6572223a 317d5d2c 22747322 zorder":1}],"ts" 00a0 3a313533 37393630 32333537 38332c22 :1537960235783," 00b0 76657222 3a223230 31383038 3238227d ver":"20190611"} ``` In which: * `06`: The SEI frame. * `64`: The SEI frame type defined by the user. Here we define it as 100. * `bd`: The length of the SEI frame. The following are some sample calculations rendered in decimal and hexadecimal: * If the length is 922, because 922 can be divided by 255 (`0xff`) three times and the remainder is 157 (`0x9d`), then `bd` is `ffffff9d`. * If the length is 572, because 572 can be divided by 255 (`0xff`) two times and the remainder is 62 (`0x3e`), then `bd` is `ffff3e`. * If the length is 234, because 234 divided by 255 (`0xff`) gives 0 and the remainder is 234 (`0xea`), then `bd` is `ea`. * Other digits: Content of the SEI frame. ### FAQ [#faq] Q: If I use the SEI frame in Media Push, is it necessary to use the signaling system to send the layout information? Do I use either signaling or SEI? A: Adding the H264/H265 SEI information to the video stream during Media Push is different from sending the uplink data. Only the `app_data` parameter of the SEI information relates to the uplink data. Q: Does the signaling system send the layout information? Why does the SEI frame contain the layout information? A: Agora puts the layout information in the SEI frame because the audience members in the `LIVE_BROADCASTING` profile also need the layout information of the current stream to set the window region of the hosts.