image Object

Compresses an image by the specified compression ratio.

Syntax

<<imageObject>>.compress(compressionRatio);

Input Parameters

Example

var imgObj = kony.image.createImage(rawBytes);
imgObj.compress(0.8);

Return Values

None.

Remarks

This method compresses the Image object's bitmap using the JPEG compression algorithm. The floating point value in the compressionRatio parameter must be in the range of 0.0<=compressionRatio<=1.0. If compressionRatio is 0.0, this method uses the minimum amount of compression. A value of 1.0 specifies the maximum amount of compression. Values outside the allowed range will be clamped to the nearest valid value. The compression data size that this method produces will vary depending on the hardware platform.

Availability

• iOS
• Android

This method crops the bitmap contained by the Image object to the size of the input rectangle.

Syntax

cropToRect(array);

Input Parameters

Example

var imgObj = kony.image.createImage(rawBytes);
imgObj.cropToRect([0, 0, 720, 720]);

Return Values

None.

Remarks

This method crops the current Image object's bitmap to the size of the rectangle specified in the array parameter, altering the bitmap in the process.

If there is no intersection between the Image object's bitmap and the rectangle in the array parameter, then no cropping is performed.

Availability

• iOS
• Android

Searches for and retrieves and image in the device's gallery of pictures.

Syntax

findImageInGallery(config);

Input Parameters

Example

var imgObj = kony.image.createImage("src.png");
imgObj.writeToGallery();

var uniqueImgIdentifier;

function onSuccess(uniqueIdentifier) {
    uniqueImgIdentifier = uniqueIdentifier;
}

config = {
    ImageName: uniqueImgIdentifier
};

var rawBytesObj = findImageInGallery(config);

Return Values

Returns an object of type kony.types.RawBytes that contains the RawBytes image data if the file exists, or null if the file is not found.

Remarks

From the Quantum Visualizer 202306 release, if the Target SDK API level of the app is set as 33, and the app uses the findImageInGallery Method of the Image API, you must enable support for granular media permissions. To do so, navigate to Project Settings > Native > Android Mobile / Tablet, and add the following entries in the Permissions tab based on the type of media files you want to access:

• Enable the READ_MEDIA_IMAGES permission to access image files.
• Enable the READ_MEDIA_AUDIO permission to access audio file.
• Enable the READ_MEDIA_VIDEO permission to access video files.

Exceptions

Retrieves the image height as an integer.

Syntax

getImageAsRawBytes(encodingFormat);

Input Parameters

Example

var imgobj = kony.image.createimage(rawbytes);
var imgobj = kony.image.createimage(form1.camera1.rawbytes);
imgobj.writetomediagallery();
var uniqueimgidentifier;

function onsuccess(uniqueidentifier) {
    uniqueimgidentifier = uniqueidentifier;
}
config = {
    imagename: uniqueimgidentifier
};

var rawbytesobj = kony.image.findimageingallery(config);
form1.img1.rawbytes = rawbytesobj;

Return Values

The Image object's bitmap in RawBytes format if an image format is specified. If not, this method returns the RawBytes data in a platform-specific formats.

Availability

• iOS
• Android

Retrieves the image height as an integer.

Syntax

getImageHeight();

Example

var imgObj = kony.image.createImage(rawBytes);
var imgHeight = imgObj.getImageHeight();
kony.print("Image height is:" + imgHeight);
form1.img1.rawbytes = rawbytesobj;

Input Parameters

None

Return Values

An integer that specifies the height of the Image.

Availability

• iOS
• Android

Retrieves the image width as an integer.

Syntax

getImageWidth();

Example

var imgObj = kony.image.createImage(rawBytes);
var imgWidth = imgObj.getImageWidth();
kony.print("Image width is:" + imgWidth);

Input Parameters

None

Return Values

An integer that specifies the object of the Image.

Availability

• iOS
• Android

Removes the internal image from the image object.

Syntax

<<imageObject>>.releaseImage();

Example

var imgObj = kony.image.createImage(rawB);
imgObj.releaseImage();

Input Parameters

None

Return Values

None

Availability

• iOS

Rotates an imageObject either in a clockwise or counter-clockwise manner, depending on the specified rotation degree.

Syntax

<<imageObject>>.rotate(degree, cropImage);

Input Parameters

Example

//Rotate image without crop filter applied
var imageObject = kony.image.createImage("Image.png");
imageObject.rotate(45);

//Rotate image without crop filter applied
var imageObject = kony.image.createImage("Image.png");
imageObject.rotate(45, true);

Return Values

None

Remarks

• The rotate API does not return a new rotated image, instead it rotates the received image.

Platform Availability

• iOS
• Android

Scales the bitmap in the current Image object to a larger or smaller size.

Syntax

scale(scaleFactor);

Input Parameters

Example

var imgObj = kony.image.createImage(rawB);
imgObj.scale(0.4);

Return Values

None

Remarks

The floating point number in the scaleFactor parameter cannot be less than zero. If it is in the range 0.0<=scaleFactor<1.0, the bitmap size will be reduced. Depending on the hardware and the size of the bitmap, distortion or blurring of the image can occur when it is reduced. If scaleFactor equals 1, this method does nothing.

When your app sets scaleFactor to a value greater than 1.0, the size of the bitmap increases. Values greater than 2.0 may result into memory warnings on some platforms. The resultant image quality may differ on platforms due to interpolation algorithms used.

Availability

• iOS
• Android

Writes an image to device's media gallery.

Syntax

writeToMediaGallery(config);

Input Parameters

config

Optional. A dictionary with configurable properties. If you do not specify the config parameter as an argument, the images will be written to the default public location based on the device's OS. You can pass the following properties in the config parameter.

if (statusOfFailure == kony.application.PERMISSION_DENIED) {
    {

    } else if (statusOfFailure == kony.image.SAVE_FAILED) {

    } else if (statusOfFailure == kony.image.INSUFFICIENT_STORAGE) {

    }
    kony.print("reason for the failure" + errorMessage);

}

Example

var config =
{
    albumName: "MyAlbum",
    extensionType: kony.image.ENCODE_PNG,
    onSuccess: successCallback2,
    onFailure: failureCallback2
};
var imgName = "sample.png";
var img = kony.image.createImage(imgName);
img.writeToMediaGallery(config);

Return Values

None

Remarks

You can make use of the writeToImageGallery function when end user wants to save an image from your app to device's gallery. The image gets saved to media gallery based on the properties you pass in the config parameter. If you do not pass the config parameter to the function, the image gets saved to the device's public location.

On iOS, there is no loss of image quality when you call the writeToImageGallery function.

Your app may require runtime permissions to access the device's media gallery. For more information on checking, requesting, and obtaining runtime permissions, please see Runtime Permissions API.

From the Quantum Visualizer 202306 release, if the Target SDK API level of the app is set as 33, and the app uses the writeToMediaGallery Method of the Image API, you must enable support for granular media permissions. To do so, navigate to Project Settings > Native > Android Mobile / Tablet, and add the following entries in the Permissions tab based on the type of media files you want to access:

• Enable the READ_MEDIA_IMAGES permission to access image files.
• Enable the READ_MEDIA_AUDIO permission to access audio file.
• Enable the READ_MEDIA_VIDEO permission to access video files.

Limitations

iOS

To use the writeToImageGallery function for the iOS platform, open the the app's Info.plist and define the NSPhotoLibraryUsageDescription key. Add the reason for accessing the media gallery as a string value to the key. Otherwise, the app crashes.

If you are using iOS 18 (or later) plugins, and the app needs write-only access to the Photo Library, ensure that you add the NSPhotoLibraryAddUsageDescription entry in the info.plist file. To use the description, ensure that the albumName key is not a part of the config.
If the albumName string is a required parameter, ensure that you add the NSPhotoLibraryUsageDescription entry in the info.plist file.
If both the NSPhotoLibraryUsageDescription and albumName entries are available in the info.plist file, the NSPhotoLibraryUsageDescription is given a higher precedence.

Android

The directory path of the primary external storage is dependent on the device. When your app calls the writeToImageGallery function , the function accesses the device's external storage to save the image. Generally, the external storage is an SD card inserted into the device that can store relatively large amount of data. There is also the possibility that the devices uses built-in storage that is distinct from the protected internal storage. The writeToImageGallery function uses the directory path of the external storage provided by the device's OS for saving images.

Platform Availability

• Android
• iOS 8 and later versions