StartRawImageDataStream

Retrieves real time camera images (if enabled) by subscribing to an event stream.

The PST REST server implements a Server-Send Events (SSEs) communication channel. When a new connection is established, if camera images are enabled, frames are served with a text/event-stream Content-Type, that follows the SSE format. Typically, a frame consist of 2 images, each of them contained in a "data:" line. This pair of images is terminated by a second carriage return.

Note

The server does not allow to have more than 2 image streams open at the same time. It is possible to close all currently opened image streams using PSTapi/CloseImageStream or PSTapi/CloseStreams. If a client closes the connection or does not read the data fast enough, the server will automatically end the connection.

More detailed information on Server Sent Events and the event-stream protocol can be found at https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events#Event_stream_format

Endpoint

GET /PSTapi/StartRawImageDataStream  HTTP/1.1
Host: address:port

Get Request example

http://localhost:7278/PSTapi/StartRawImageDataStream

Response

Open a Server-Send Events (SSEs) stream, with a text/event-stream Content-Type. Each message represents a new capture that follows the SSE format. A message has several "data:" lines representing each camera and is terminated by a carriage return character \n. Each "data:" line represents a base64 encoded JPEG camera image.

SSE Data Object

Key	Value Type	Description
data	base64 string	A base 64 string representing a JPEG image

Example

data: <a base64 string representing a JPEG image, the left/right camera, 1st frame>
data: <a base64 string representing a JPEG image, the left/right camera, 1st frame><br>  data: <a base64 string representing a JPEG image, the left/right camera, 2nd frame>
data: <a base64 string representing a JPEG image, the left/right camera, 2nd frame><br>  data: <a base64 string representing a JPEG image, the left/right camera, 3rd frame>
data: <a base64 string representing a JPEG image, the left/right camera, 3rd frame><br>  ...

Verification table

Status Code	Content Example	Meaning
200	JSON event stream "data:"	Stream of "data" objects containing the images
429	{"message":"TOO_MANY_IMAGES_STREAM_ALREADY_OPENED"}	There are 2 image streams open already. cf. CloseImageStream
500	{"message":"TrackerException: <...>"}	An other type of internal error