Phonegap - Retrieve photo from Camera Roll via path

Question

In my PhoneGap/jQuery Mobile app, I'm currently using PhoneGaps' Camera API to allow the user to take a photo, which is also stored in the Camera Roll. I'm setting DestinationType to FILE_URI and saving this path in a local db. However, FILE_URI is a path to a temporary location that is destroyed when the app is closed. I was thinking of saving the name of the image and then retrieving the image from the Camera Roll. Is there a path I can use to later retrieve the images in the Camera Roll?

I was saving the images as Base64 in the db, but I'm a little weary of this method because of this note in the PhoneGap API Doc:

Note: The image quality of pictures taken using the camera on newer devices is quite good. Encoding such images using Base64 has caused memory issues on some of these devices (iPhone 4, BlackBerry Torch 9800). Therefore, using FILE_URI as the 'Camera.destinationType' is highly recommended.

EDIT:

Got it working with @Simon MacDonald's answer. Here is my stripped-down code:

function capturePhoto() {
    navigator.camera.getPicture(onPhotoURISuccess, onFail, { quality: 25, destinationType: Camera.DestinationType.FILE_URI });
}

function onPhotoURISuccess(imageURI) {
    createFileEntry(imageURI);
}

function createFileEntry(imageURI) {
    window.resolveLocalFileSystemURI(imageURI, copyPhoto, fail);    
}

function copyPhoto(fileEntry) {
    window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, function(fileSys) { 
        fileSys.root.getDirectory("photos", {create: true, exclusive: false}, function(dir) { 
                fileEntry.copyTo(dir, "file.jpg", onCopySuccess, fail); 
            }, fail); 
    }, fail); 
}

function onCopySuccess(entry) {
    console.log(entry.fullPath)
}

function fail(error) {
    console.log(error.code);
}

Answer 1

After you retrieve the file using the FILE_URI method you should use the File API to copy the image from the temp folder to the Documents folder and store the new path in your DB.

So you would take the result of your getPicture() pass it to window.resolveLocalFileSystemURI() to get a FileEntry. Then you can call FileEntry.copyTo() method to back up your file.