Annotation: iOS SDK – Video API

Availability: iOS SDK v1.5.6+

The Annotation feature allows you to annotate on a Remote Stream. To support Annotations, you need to enable Canvas Streaming during Room Creation by setting: { canvas: true; }} in the JSON payload. To implement Annotation, you need to add Annotation Toolbar before you can start Annotations.

Table of Contents

• Annotation Toolbar
• Start / Stop Annotation

Add Annotation Toolbar

Initiate Annotation Toolbar using the following code in XML:

EnxToolBar *toolBar = [[EnxToolBar alloc] initWithFrame:CGRectMake(X, Y, width, height)];

Start Annotation

The EnxRoom.startAnnotation() is used to start Annotation on a given Stream object.

Class: EnxRoom

Method:

• -(void)startAnnotation:(EnxStream *_Nonnull)stream 

Parameter: 

EnxStream – Stream Object to be annotated.

Delegate Methods:

• -room:didStartAnnotationACK:(NSArray *_Nullable)Data – Acknowledgment to the Annotator when Annotation starts.
• -room:didAnnotationStarted:(NSArray *_Nullable)Data – Notification to everyone in the Room when Annotation starts.

// Start Annotation
-(void)startAnnotation:(EnxStream*_Nonnull)stream;

// Stop Annotation
-(void)stopAnnotation;  

// Notification to all - Annotation started
-(void)room: (EnxRoom *_Nullable) room didAnnotationStarted: (NSArray *_Nullable) Data; 

// Acknowlegement to Annotator - Annotation started
-(void)room: (EnxRoom *_Nullable) room didStartAnnotationACK: (NSArray *_Nullable) Data; 

// Notification to all - Annotation stopped
-(void)room: (EnxRoom *_Nullable) room didAnnotationStopped: (NSArray *_Nullable) Data; 

// Acknowlegement to Annotator - Annotation stopped
-(void)room: (EnxRoom *_Nullable) room didStoppedAnnotationACK: (NSArray *_Nullable) Data; 

Stop Annotation

The EnxRoom.stopAnnotation() method is used to stop Annotations.

Method:

-(void)stopAnnotation 

Delegate Methods:

• -room:didStoppedAnnotationACK:(NSArray *_Nullable)Data – Acknowledgment to the Annotator when Annotation stops.
• -room:didAnnotationStopped:(NSArray *_Nullable)Data – Notification to everyone in the Room when Annotation stops.

Error Codes / Exceptions: 

Code	Description
5093	Annotation Access denied.
5104	Repeated startAnnotation() call made while Annotations already active in the Room.
5106	Repeated startAnnotation() call made while a previous request is in process.
5108	Invalid Stream passed to startAnnotation().
5109	Failed to publish Annotation Stream.
5112	Annotation support available in Landscape Mode only.
5094	Repeated stopAnnotation() call made while a previous request is in process.

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