CameraView/docs/_posts/2018-12-20-controls.md

layout	title	description	category	order	date	disqus
page	Controls	Configuring output parameters and capture options	docs	2	2018-12-20 21:08:53	1

CameraView supports a wide range of controls that will control the behavior of the sensor or the quality of the output.

Everything can be controlled through XML parameters or programmatically. For convenience, most options are represented by enum classes extending the Control class. This makes it possible to use CameraView.set(Control) to set the given control, CameraView.get(Class<Control>) to get it, or CameraOptions.supports(Control) to see if it is supported.

XML Attributes

<com.otaliastudios.cameraview.CameraView
    app:cameraFacing="front|back"
    app:cameraFlash="off|on|auto|torch"
    app:cameraWhiteBalance="auto|incandescent|fluorescent|daylight|cloudy"
    app:cameraHdr="off|on"
    app:cameraPictureFormat="jpeg|dng"
    app:cameraAudio="on|off|mono|stereo"
    app:cameraAudioBitRate="0"
    app:cameraVideoCodec="deviceDefault|h263|h264"
    app:cameraVideoMaxSize="0"
    app:cameraVideoMaxDuration="0"
    app:cameraVideoBitRate="0"
    app:cameraPreviewFrameRate="30"/>

APIs

cameraFacing

Which camera to use, either back facing or front facing. Defaults to the first available value (tries BACK first). The available values are exposed through the CameraOptions object.

cameraView.setFacing(Facing.BACK);
cameraView.setFacing(Facing.FRONT);

cameraFlash

Flash mode, either off, on, auto or torch. Defaults to OFF. The available values are exposed through the CameraOptions object.

cameraView.setFlash(Flash.OFF);
cameraView.setFlash(Flash.ON);
cameraView.setFlash(Flash.AUTO);
cameraView.setFlash(Flash.TORCH);

cameraVideoCodec

Sets the encoder for video recordings. Defaults to DEVICE_DEFAULT, which should typically be H_264. The available values are exposed through the CameraOptions object.

cameraView.setVideoCodec(VideoCodec.DEVICE_DEFAULT);
cameraView.setVideoCodec(VideoCodec.H_263);
cameraView.setVideoCodec(VideoCodec.H_264);

cameraWhiteBalance

Sets the desired white balance for the current session. Defaults to AUTO. The available values are exposed through the CameraOptions object.

cameraView.setWhiteBalance(WhiteBalance.AUTO);
cameraView.setWhiteBalance(WhiteBalance.INCANDESCENT);
cameraView.setWhiteBalance(WhiteBalance.FLUORESCENT);
cameraView.setWhiteBalance(WhiteBalance.DAYLIGHT);
cameraView.setWhiteBalance(WhiteBalance.CLOUDY);

cameraHdr

Turns on or off HDR captures. Defaults to OFF. The available values are exposed through the CameraOptions object.

cameraView.setHdr(Hdr.OFF);
cameraView.setHdr(Hdr.ON);

cameraPictureFormat

The format for pictures taken with takePicture(). Does not apply to picture snapshots taken with takePictureSnapshot(). The JPEG value is always supported, while for other values support might change depending on the engine and the device sensor. The available values are exposed through the CameraOptions object.

cameraView.setPictureFormat(PictureFormat.JPEG);
cameraView.setPictureFormat(PictureFormat.DNG);

cameraAudio

Turns on or off audio stream while recording videos. Defaults to ON. The available values are exposed through the CameraOptions object.

cameraView.setAudio(Audio.OFF);
cameraView.setAudio(Audio.ON); // on but depends on video config
cameraView.setAudio(Audio.MONO); // force mono
cameraView.setAudio(Audio.STEREO); // force stereo

cameraAudioBitRate

Controls the audio bit rate in bits per second. Use 0 or a negative value to fallback to the encoder default. Defaults to 0.

cameraView.setAudioBitRate(0);
cameraView.setAudioBitRate(64000);

cameraVideoMaxSize

Defines the maximum size in bytes for recorded video files. Once this size is reached, the recording will automatically stop. Defaults to unlimited size. Use 0 or negatives to disable.

cameraView.setVideoMaxSize(100000);
cameraView.setVideoMaxSize(0); // Disable

cameraVideoMaxDuration

Defines the maximum duration in milliseconds for video recordings. Once this duration is reached, the recording will automatically stop. Defaults to unlimited duration. Use 0 or negatives to disable.

cameraView.setVideoMaxDuration(100000);
cameraView.setVideoMaxDuration(0); // Disable

cameraVideoBitRate

Controls the video bit rate in bits per second. Use 0 or a negative value to fallback to the encoder default. Defaults to 0.

cameraView.setVideoBitRate(0);
cameraView.setVideoBitRate(4000000);

cameraPreviewFrameRate

Controls the preview frame rate, in frames per second. Use a value of 0F to restore the camera default value.

cameraView.setPreviewFrameRate(30F);
cameraView.setPreviewFrameRate(0F);

The preview frame rate is an important parameter because it will also control (broadly) the rate at which frame processor frames are dispatched, the video snapshots frame rate, and the rate at which real-time filters are invoked. The available values are exposed through the CameraOptions object:

float min = options.getPreviewFrameRateMinValue();
float max = options.getPreviewFrameRateMaxValue();

Zoom

There are two ways to control the zoom value:

• User can zoom in or out with a Gesture
• The developer can start manual zoom with the setZoom(float) API, passing in a value between 0 and 1.

Both actions will trigger the zoom callback, which can be used, for example, to draw a seek bar:

cameraView.addCameraListener(new CameraListener() {
    
    @Override
    public void onZoomChanged(float newValue, @NonNull float[] bounds, @Nullable PointF[] fingers) {
        // newValue: the new zoom value
        // bounds: this is always [0, 1]
        // fingers: if caused by touch gestures, these is the fingers position
    }
});

Zoom is not guaranteed to be supported: check the CameraOptions to be sure.