TiRotate - Android Image Rotation Module

Is it a Titanium bug or an Android bug or a handset-maker bug? Who cares. Sometimes you take a photo with your phone upright (portrait) and it ends up sideways. This module is meant to fix that.

The TiRotate module will rotate an image to an orientation you specify and set its EXIF orientation tag to reflect that orientation (so that web clients, etc. will respect the new orientation).

Note: This module doesn't support free rotation. You can rotate to any of the cardinal coordinates -- portrait, landscape right, upside-down, landscape left.

Obtaining / Installing

Recommended

$ gittio install com.skypanther.tirotate

###Manual method (works, but why not use gittio?):

1. Download the zip from the dist folder
2. Unzip to your app's modules/android folder
3. Add the module to the modules tag:

<modules>
	<module platform="android">com.skypanther.tirotate</module>
</modules>

Using

In your controller, instantiate it and use it:

var tirotate = require('com.skypanther.tirotate');
var file = Ti.Filesystem.getFile(Ti.Filesystem.applicationDataDirectory, 'photo.jpg');
var orientation = tirotate.getExifOrientation(file.nativePath);
if (orientation === tirotate.ORIENTATION_NORMAL) {
	alert("The image is portrait");
}

Methods

Method	Description
getExifOrientationDegrees(path)	Get the image's EXIF orientation in degrees
getExifOrientation(path)	Get the image's EXIF orientation tag value
setExifOrientation(path, targetOrientation)	Set the image's EXIF orientation tag
rotate(path, targetOrientation)	Rotates the image to specified orientation and updates its EXIF tag

Examples:

Get the orientation of an image file in degrees

tirotate.getExifOrientationDegrees(file.nativePath); // e.g. 90

Get the EXIF orientation tag value

tirotate.getExifOrientation(file.nativePath); // 1 (ORIENTATION_NORMAL)

(The resulting value will match the constants defined by the native ExifInterface. See https://developer.android.com/reference/android/media/ExifInterface.html for those values.)

Set the EXIF orientation tag value

tirotate.setExifOrientation(file.nativePath, tirotate.PORTRAIT);

Alternatively:

tirotate.setExifOrientation(file.nativePath, tirotate.ORIENTATION_NORMAL);

Rotate the image AND set its EXIF tag to the new orientation

if (tirotate.rotate(file.nativePath, tirotate.PORTRAIT)) {
	// successfully rotated
} else {
	// failed to rotate
}

Alternatively:

if (tirotate.rotate(file.nativePath, tirotate.ORIENTATION_NORMAL)) {
	// successfully rotated
} else {
	// failed to rotate
}

Constants

The module defines a few constants that you should use when interacting with images via the module's methods. For example, assuming you instantiate the module in a variable tirotate you would reference the EXIF portrait orientation as tirotate.ORIENTATION_NORMAL

Constant	Description	Value
DEGREES_PORTRAIT	Integer rotation, used when reading the EXIF orientation of an image	0
DEGREES_LANDSCAPE_RIGHT	Integer rotation, used when reading the EXIF orientation of an image	90
DEGREES_UPSIDE_PORTRAIT	Integer rotation, used when reading the EXIF orientation of an image	180
DEGREES_LANDSCAPE_LEFT	Integer rotation, used when reading the EXIF orientation of an image	270
PORTRAIT	String used when rotating an image to a specific orientation	"portrait"
LANDSCAPE_RIGHT	String used when rotating an image to a specific orientation	"landscape_right"
UPSIDE_PORTRAIT	String used when rotating an image to a specific orientation	"upside_portrait"
LANDSCAPE_LEFT	String used when rotating an image to a specific orientation	"landscape_left"
ORIENTATION_NORMAL	Corresponds to the EXIF orientation constant for the portrait orientation	ExifInterface.ORIENTATION_NORMAL
ORIENTATION_ROTATE_90	Corresponds to the EXIF orientation constant for the landscape right orientation	ExifInterface.ORIENTATION_ROTATE_90
ORIENTATION_ROTATE_180	Corresponds to the EXIF orientation constant for the upside-down orientation	ExifInterface.ORIENTATION_ROTATE_180
ORIENTATION_ROTATE_270	Corresponds to the EXIF orientation constant for the landscape left orientation	ExifInterface.ORIENTATION_ROTATE_270
ORIENTATION_UNDEFINED	Corresponds to the EXIF orientation constant for the undefined orientation	ExifInterface.ORIENTATION_UNDEFINED

Contributing

I welcome any and all help, naturally. I could specifically use testing on various Android devices. Open issues, or even better, submit a pull request.

License & Copyright

Copyright © 2017 Tim Poulsen distributed under the MIT license.