Device Camera

The device camera bridge drives this device’s own camera from a page anywhere: a live MJPEG viewfinder, photos and video filed into a file root, lens, zoom, torch and effects.

Install and register

dotnet add package Shiny.AppDeviceBridge.Camera

builder.UseAppDeviceBridge(
    bridge => bridge.AddCameraBridge(),
    webApp => { /* … */ }
);

Client	C#	TypeScript
ICameraBridge	AddCameraBridgeClient()	CameraBridge

Details

This device’s own camera, driven from a page anywhere — the reason being a phone on a mount, framed and fired from a laptop across the room. Not the camera of the machine showing the page: that’s getUserMedia (see Camera, microphone and location in the page). Android, iOS, Mac Catalyst, macOS and Windows, through Shiny’s CameraView; Linux has no camera and answers 501.

bridge.AddCameraBridge(o =>
{
    o.Root = "data";                 // captures are filed here…
    o.Folder = "camera";             // …as camera/IMG_20260916-201502.jpg, camera/VID_….mov
});

• A camera screen, not a background service. The camera runs on a view on screen — iOS won’t run one in the background at all — so GET camera says whether one is live, and until it is every command answers 409 camera_not_open. That’s a normal state: show it as “open the camera on the device”, not as an error.
• Opening it from afar. POST camera/open (202) asks the device to show its camera. Unless something handles CameraBridgeSession.OpenRequested, the bridge pushes its own CameraBridgePage over the web app — shutter, photo and video, flip, torch, close. POST camera/close closes it. For a camera screen of your own, put a CameraBridgeView on it, set PresentWhenOpened = false and navigate there from OpenRequested; the buttons on that screen and the requests from a page run the same methods.
• Driving it. POST camera/photo and POST/DELETE camera/recording capture at full resolution and file into the file root, answering { file: { root, path }, kind, size, … } for the files bridge. PUT camera/settings is a patch — videoMode, facing, cameraId, active, filter, torchOn, zoom — so two viewers don’t undo each other; changing the camera mid-recording is a 422 camera_state. Phones flip front and back; desktops list cameras and set choosesCamera, since none of theirs is front or back.
• The viewfinder. GET camera/preview is multipart/x-mixed-replace MJPEG an <img> plays: small (720 px) and 12 frames a second by default (PreviewMaxEdge, PreviewFramesPerSecond, PreviewQuality), because latency matters more than smoothness when framing. The device encodes only while someone watches, and a slow viewer gets the newest frame.
• Everyone follows the device. camera.status carries the whole status whenever anything changes — somebody picks the phone up and switches to video, and every page’s controls follow.
• Filing elsewhere. Register an ICameraCaptureStore before AddCameraBridge to file captures through your own storage.
• Platform setup: NSCameraUsageDescription and NSMicrophoneUsageDescription on Apple platforms (plus the camera and audio-input entitlements where sandboxed), CAMERA and RECORD_AUDIO on Android, the webcam and microphone capabilities on Windows. POST camera/access prompts where the platform will.

<img src="_bridge/camera/preview?t=1726517702" />   <!-- a new query each time it's shown -->

const camera = new CameraBridge();
camera.onStatus(status => render(status));
await camera.open();
const photo = await camera.takePhoto();              // { file: { root: "data", path: "camera/IMG_….jpg" }, … }
await camera.updateSettings({ videoMode: true, zoom: 2 });

Requests

GET/_bridge/cameraThe camera's state, and whether this platform has one and the app may use it — without prompting.POST/_bridge/camera/accessPrompts for camera access where the platform still will, and says where it stands.POST/_bridge/camera/openAsks the device to show its camera screen.POST/_bridge/camera/closeCloses the camera screen the bridge opened.POST/_bridge/camera/photoTakes a photo at full resolution and files it.POST/_bridge/camera/recordingStarts recording video.DELETE/_bridge/camera/recordingStops recording and files the video.PUT/_bridge/camera/settingsChanges the live camera, and answers with the state it is in afterwards.

GET/_bridge/camera#

The camera's state, and whether this platform has one and the app may use it — without prompting.

C#ICameraBridge.GetStatusAsyncTSCameraBridge.getStatus

Response

200 CameraStatus

CameraStatus · 19 fields

supported	boolean	Whether this platform has a camera to bridge. False on Linux.
access	AccessState	The camera permission, without prompting.
live	boolean	Whether a camera screen is open on the device, so there is something to drive.
active	boolean	Whether that screen has the camera turned on. A live camera can be put down without closing it.
videoMode	boolean	Video rather than photos. The two are modes, never both at once.
recording	boolean	Whether a video is being recorded.
busy	boolean	Whether a capture is in progress.
facing	CameraFacing	Which way the camera in use points.
cameraId	string | null	The camera pinned by id, or null when the device chose by facing.
cameras	CameraDevice[] | null	The cameras this device offers.
choosesCamera	boolean	Whether this device picks a camera from cameras rather than flipping between front and back — true on desktops, whose cameras are neither.
torchOn	boolean	Whether the torch is lit.
torchAvailable	boolean	Whether there is a torch to light. False on front cameras and desktops.
zoom	number	The zoom factor, between minZoom and maxZoom.
minZoom	number	The least the camera in use zooms.
maxZoom	number	The most the camera in use zooms.
filter	CameraFilter	The effect in use.
lastCapture	CameraCapture | null	The most recent capture this camera filed.
message	string | null	A sentence for people: what the camera is doing, or why it is not.

POST/_bridge/camera/access#

Prompts for camera access where the platform still will, and says where it stands.

C#ICameraBridge.RequestAccessAsyncTSCameraBridge.requestAccess

Response

200 CameraAccessResult

CameraAccessResult · 1 field

access

AccessState

Where the camera permission stands after asking.

POST/_bridge/camera/open#

Asks the device to show its camera screen. Answers straight away; the camera arrives on onStatus when it is up. Does nothing when one is already open.

C#ICameraBridge.OpenAsyncTSCameraBridge.open

Response

204 No content

POST/_bridge/camera/close#

Closes the camera screen the bridge opened. A camera screen the app opened itself is the app's to close.

C#ICameraBridge.CloseAsyncTSCameraBridge.close

Response

204 No content

POST/_bridge/camera/photo#

Takes a photo at full resolution and files it.

C#ICameraBridge.TakePhotoAsyncTSCameraBridge.takePhoto

Response

200 CameraCapture

CameraCapture · 6 fields

file	BridgeFile	Where it was filed.
kind	CameraCaptureKind	A photo or a video.
size	number	Bytes.
width	number | null	A photo's width in pixels.
height	number | null	A photo's height in pixels.
durationSeconds	number | null	A video's length, where the platform reports one.

POST/_bridge/camera/recording#

Starts recording video. The camera has to be in video mode.

C#ICameraBridge.StartRecordingAsyncTSCameraBridge.startRecording

Response

204 No content

DELETE/_bridge/camera/recording#

Stops recording and files the video.

C#ICameraBridge.StopRecordingAsyncTSCameraBridge.stopRecording

Response

200 CameraCapture

CameraCapture · 6 fields

file	BridgeFile	Where it was filed.
kind	CameraCaptureKind	A photo or a video.
size	number	Bytes.
width	number | null	A photo's width in pixels.
height	number | null	A photo's height in pixels.
durationSeconds	number | null	A video's length, where the platform reports one.

PUT/_bridge/camera/settings#

Changes the live camera, and answers with the state it is in afterwards.

C#ICameraBridge.UpdateSettingsAsyncTSCameraBridge.updateSettings

Body

application/json · CameraSettingsInput

CameraSettingsInput · 7 fields

videoMode	boolean | null	Switch between photos and video. Refused while recording.
facing	CameraFacing | null	Choose a camera by which way it points. Refused while recording.
cameraId	string | null	Pin a camera by id, which wins over facing; empty unpins it. Refused while recording.
active	boolean | null	Turn the camera on or off without closing its screen. Refused while recording.
filter	CameraFilter | null	The effect to apply.
torchOn	boolean | null	Light the torch, where there is one.
zoom	number | null	The zoom factor, clamped to the camera's range.

Response

200 CameraStatus

CameraStatus · 19 fields

supported	boolean	Whether this platform has a camera to bridge. False on Linux.
access	AccessState	The camera permission, without prompting.
live	boolean	Whether a camera screen is open on the device, so there is something to drive.
active	boolean	Whether that screen has the camera turned on. A live camera can be put down without closing it.
videoMode	boolean	Video rather than photos. The two are modes, never both at once.
recording	boolean	Whether a video is being recorded.
busy	boolean	Whether a capture is in progress.
facing	CameraFacing	Which way the camera in use points.
cameraId	string | null	The camera pinned by id, or null when the device chose by facing.
cameras	CameraDevice[] | null	The cameras this device offers.
choosesCamera	boolean	Whether this device picks a camera from cameras rather than flipping between front and back — true on desktops, whose cameras are neither.
torchOn	boolean	Whether the torch is lit.
torchAvailable	boolean	Whether there is a torch to light. False on front cameras and desktops.
zoom	number	The zoom factor, between minZoom and maxZoom.
minZoom	number	The least the camera in use zooms.
maxZoom	number	The most the camera in use zooms.
filter	CameraFilter	The effect in use.
lastCapture	CameraCapture | null	The most recent capture this camera filed.
message	string | null	A sentence for people: what the camera is doing, or why it is not.

Events

EVENTcamera.status#

The camera changed — opened, closed, switched mode, filed a capture. Raised with the whole state.

C#ICameraBridge.OnStatusAsyncTSCameraBridge.onStatus

Payload

CameraStatus

supported	boolean	Whether this platform has a camera to bridge. False on Linux.
access	AccessState	The camera permission, without prompting.
live	boolean	Whether a camera screen is open on the device, so there is something to drive.
active	boolean	Whether that screen has the camera turned on. A live camera can be put down without closing it.
videoMode	boolean	Video rather than photos. The two are modes, never both at once.
recording	boolean	Whether a video is being recorded.
busy	boolean	Whether a capture is in progress.
facing	CameraFacing	Which way the camera in use points.
cameraId	string | null	The camera pinned by id, or null when the device chose by facing.
cameras	CameraDevice[] | null	The cameras this device offers.
choosesCamera	boolean	Whether this device picks a camera from cameras rather than flipping between front and back — true on desktops, whose cameras are neither.
torchOn	boolean	Whether the torch is lit.
torchAvailable	boolean	Whether there is a torch to light. False on front cameras and desktops.
zoom	number	The zoom factor, between minZoom and maxZoom.
minZoom	number	The least the camera in use zooms.
maxZoom	number	The most the camera in use zooms.
filter	CameraFilter	The effect in use.
lastCapture	CameraCapture | null	The most recent capture this camera filed.
message	string | null	A sentence for people: what the camera is doing, or why it is not.

Types

JSON property names are camelCase and enums travel as their names. A ? marks a property the payload may omit;| null one that may be null.

CameraStatusobject#

The camera as it is right now. Everything about the camera itself is meaningless while live is false: no camera screen is open on the device, and every command answers 409.

supported	boolean	Whether this platform has a camera to bridge. False on Linux.
access	AccessState	The camera permission, without prompting.
live	boolean	Whether a camera screen is open on the device, so there is something to drive.
active	boolean	Whether that screen has the camera turned on. A live camera can be put down without closing it.
videoMode	boolean	Video rather than photos. The two are modes, never both at once.
recording	boolean	Whether a video is being recorded.
busy	boolean	Whether a capture is in progress.
facing	CameraFacing	Which way the camera in use points.
cameraId	string | null	The camera pinned by id, or null when the device chose by facing.
cameras	CameraDevice[] | null	The cameras this device offers.
choosesCamera	boolean	Whether this device picks a camera from cameras rather than flipping between front and back — true on desktops, whose cameras are neither.
torchOn	boolean	Whether the torch is lit.
torchAvailable	boolean	Whether there is a torch to light. False on front cameras and desktops.
zoom	number	The zoom factor, between minZoom and maxZoom.
minZoom	number	The least the camera in use zooms.
maxZoom	number	The most the camera in use zooms.
filter	CameraFilter	The effect in use.
lastCapture	CameraCapture | null	The most recent capture this camera filed.
message	string | null	A sentence for people: what the camera is doing, or why it is not.

AccessStateenum#

Where a permission stands. Reported by every bridge that needs one; the names match Shiny's own.

"Unknown""NotSupported""NotSetup""Disabled""Restricted""Denied""Available"

CameraFacingenum#

Which way a camera points. Most desktop cameras are External, which is neither front nor back.

"Back""Front""External"

CameraDeviceobject#

One camera the device can open.

id	string	What cameraId takes.
name	string	The name the platform gives it — "FaceTime HD Camera", "Back Camera".
facing	CameraFacing	Which way it points.
isDefault	boolean	Whether the platform would choose it when nothing is pinned.

CameraFilterenum#

The camera's built-in effects, applied to the preview, the viewfinder stream and the captures alike.

"None""Mono""Noir""Sepia""Invert""Vivid""Cool""Warm""Fade""Chrome""Instant""Tonal"

CameraCaptureobject#

A capture, filed into a file root and read through the files bridge.

file	BridgeFile	Where it was filed.
kind	CameraCaptureKind	A photo or a video.
size	number	Bytes.
width	number | null	A photo's width in pixels.
height	number | null	A photo's height in pixels.
durationSeconds	number | null	A video's length, where the platform reports one.

BridgeFileobject#

A file the page can reach through the files bridge: a named root and a path inside it. Bridges that take or return a file use this, so nothing reaches the page that /_bridge/files would not also serve.

root	string
path	string

CameraCaptureKindenum#

"Photo""Video"

CameraAccessResultobject#

access

AccessState

Where the camera permission stands after asking.

CameraSettingsInputobject#

A change to the live camera. Every member is optional and null leaves it alone — a patch, so two viewers of the same camera do not undo each other's changes.

videoMode?	boolean | null	Switch between photos and video. Refused while recording.
facing?	CameraFacing | null	Choose a camera by which way it points. Refused while recording.
cameraId?	string | null	Pin a camera by id, which wins over facing; empty unpins it. Refused while recording.
active?	boolean | null	Turn the camera on or off without closing its screen. Refused while recording.
filter?	CameraFilter | null	The effect to apply.
torchOn?	boolean | null	Light the torch, where there is one.
zoom?	number | null	The zoom factor, clamped to the camera's range.

Security

These routes sit under AppDeviceBridgePolicies.Bridges like every other bridge: callers on this device by default. See Security.