Blackmagic Design Web Presenter 4K - Manual (Page 216)

Status Updates
When any device parameter is changed on the Web Presenter server by any client, such as the
Blackmagic Web Presenter Setup utility, the Web Presenter server resends the applicable
status block, containing only the items that have changed. Status updates can also occur due to
external changes such as tethering to a smartphone or when a streaming service is
disconnected.
For example. if the input video mode is set to Auto, the following block will be sent:
STREAM SETTINGS: ↵
Video Mode: Auto ↵
↵
Requesting Changes
To change one or more parameters in a block, the client should send the appropriate block
header in the same form the Web Presenter server sends, followed by the key/value pairs to be
changed. For example, to change the input video format to 1080p59.94, the user should send
the following block:
STREAM SETTINGS: ↵
Video Mode: 1080p59.94 ↵
↵
The block must be terminated by a blank line. On receipt of a blank line, the Web Presenter
server will either acknowledge the request by responding:
ACK ↵
↵
or if unable to parse the block responding with:
NACK ↵
↵
After a positive response, the client should expect to see a status update from the Web
Presenter server showing the status change. This is likely to be the same as the command that
was sent, sometimes followed by other blocks providing data specific to the change.
STREAM SETTINGS: ↵
Video Mode: 1080p59.94 ↵
↵
If the Web Presenter server does not understand a key in the requested block, the key will be
ignored. If an invalid value is provided for a known key, then the request is ignored and the Web
Presenter will respond with the existing value for the key. In both cases the Web Presenter
server will still respond with an ACK.
STREAM SETTINGS: ↵
Video Mode: UnsupportedMode ↵
↵
ACK ↵
↵
STREAM SETTINGS: ↵
Video Mode: 1080p59.94 ↵
↵
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