OpenDroneMap-WebODM/app/static/app/js/vendor/osgjs/osg/Image.js

'use strict';
var Notify = require( 'osg/notify' );
var MACROUTILS = require( 'osg/Utils' );
var Object = require( 'osg/Object' );

var ImageBitmap = window.ImageBitmap || function () {};

var ImageObject = function ( image ) {
    Object.call( this );

    this._imageObject = undefined;
    this._url = undefined;
    this._width = undefined;
    this._height = undefined;
    this._dirty = true;
    this._mipmap = [];

    if ( image ) {
        this.setImage( image );
    }

    this._isGreyscale = undefined;
};

ImageObject.prototype = MACROUTILS.objectLibraryClass( MACROUTILS.objectInherit( Object.prototype, {

    dirty: function () {
        this._isGreyscale = undefined;
        this._dirty = true;
    },

    isDirty: function () {
        return this._dirty;
    },

    setDirty: function ( bool ) {
        this._dirty = bool;
    },

    getImage: function () {
        return ( this._imageObject instanceof ImageObject ) ? this._imageObject.getImage() : this._imageObject;
    },

    getURL: function () {
        return this._url;
    },

    setURL: function ( url ) {
        this._url = url;
    },

    useOrCreateImage: function ( img ) {
        return ( img instanceof( ImageObject ) === false ) ? new ImageObject( img ) : img;
    },

    setImage: function ( img ) {
        if ( !this._url && img && ( img.src || img.currentSrc ) ) {
            // TODO what is currentSrc ?
            this._url = img.src || img.currentSrc;
        }

        this._mipmap.length = 0;

        // img can be an image or an array of image if specify the
        // all mipmap levels
        if ( Array.isArray( img ) ) {
            for ( var i = 0, nbImg = img.length; i < nbImg; i++ ) {
                this._mipmap.push( this.useOrCreateImage( img[ i ] ) );
            }
            this.setWidth( this._mipmap[ 0 ].getWidth() );
            this.setHeight( this._mipmap[ 0 ].getHeight() );
        } else {
            this._mipmap.push( img );
        }

        this._imageObject = this._mipmap[ 0 ];
        this.dirty();
    },

    isCanvas: function () {
        return this.getImage() instanceof window.HTMLCanvasElement;
    },

    isBitmap: function () {
        return this.getImage() instanceof ImageBitmap;
    },

    isVideo: function () {
        return this.getImage() instanceof window.HTMLVideoElement;
    },

    isImage: function () {
        return this.getImage() instanceof window.Image;
    },

    isTypedArray: function () {
        var img = this.getImage();
        return img instanceof Uint8Array || img instanceof Float32Array || img instanceof Uint16Array;
    },

    setWidth: function ( w ) {
        this._width = w;
    },

    setHeight: function ( h ) {
        this._height = h;
    },

    getWidth: function () {
        var img = this.getImage();
        if ( this.isImage() ) {
            return img.naturalWidth;
        } else if ( this.isVideo() ) {
            return img.videoWidth;
        } else if ( this.isCanvas() || this.isBitmap() ) {
            return img.width;
        }
        return this._width;
    },

    getHeight: function () {
        var img = this.getImage();
        if ( this.isImage() ) {
            return img.naturalHeight;
        } else if ( this.isVideo() ) {
            return img.videoHeight;
        } else if ( this.isCanvas() || this.isBitmap() ) {
            return img.height;
        }
        return this._height;
    },

    isGreyscale: function ( nbSamples ) {
        if ( this._isGreyscale !== undefined )
            return this._isGreyscale;

        if ( this._imageObject !== undefined && this.isReady() && this._isGreyscale === undefined ) {

            var canvas = this._imageObject;
            if ( !this.isCanvas() ) {
                canvas = document.createElement( 'canvas' );
            }
            var ctx = canvas.getContext( '2d' );
            canvas.width = this._imageObject.width;
            canvas.height = this._imageObject.height;
            ctx.drawImage( this._imageObject, 0, 0 );

            var sampleX, sampleY;
            // cap sample if needed
            if ( !nbSamples ) {
                sampleX = canvas.width;
                sampleY = canvas.height;
            }
            if ( nbSamples > 0 ) {
                nbSamples = Math.min( Math.min( canvas.width, canvas.height ), nbSamples );
                sampleX = sampleY = nbSamples;
            }

            var isGreyscale = true;
            var xFactor = canvas.width / ( sampleX );
            var yFactor = canvas.height / ( sampleY );
            for ( var i = 0; i < sampleX; i++ ) {
                for ( var j = 0; j < sampleY; j++ ) {
                    var x = Math.floor( xFactor * ( i + 0.5 ) ),
                        y = Math.floor( yFactor * ( j + 0.5 ) );
                    var data = ctx.getImageData( x, y, 1, 1 ).data;
                    if ( !( data[ 0 ] === data[ 1 ] && data[ 0 ] === data[ 2 ] ) ) {
                        isGreyscale = false;
                        break;
                    }
                }
            }
            this._isGreyscale = isGreyscale;
        }

        return this._isGreyscale;
    },

    isReady: function () {

        // image is a osgImage
        if ( this._imageObject && this._imageObject instanceof ImageObject ) {
            return this._imageObject.isReady();
        }


        // image are ready for static data
        if ( this.isCanvas() || this.isTypedArray() || this.isBitmap() ) {
            return true;
        }

        if ( this.isImage() ) {
            var image = this.getImage();
            if ( image.complete ) {
                if ( image.naturalWidth !== undefined && image.naturalWidth === 0 ) {
                    return false;
                }

                return true;
            }
        }

        if ( this.isVideo() ) {
            if ( this.getWidth() !== 0 ) return true;
        }

        // here means we have something but we don't know what
        // Check if the object is not a image
        // by "feature" detect it
        var imageTry = this.getImage();
        if ( imageTry.complete ) {
            if ( imageTry.naturalWidth !== undefined && imageTry.naturalWidth === 0 ) {
                return false;
            }
            return true;
        }

        // It's not something we recognise
        /*develblock:start*/
        Notify.warn( 'Warning can\'t detect image object ' );
        /*develblock:end*/
        return false;
    },

    getMipmap: function () {
        return this._mipmap;
    },

    hasMipmap: function () {
        return this._mipmap.length > 1;
    },

    release: function () {
        this._mipmap.length = 0;
        this._imageObject = undefined;
    }
} ), 'osg', 'Image' );

MACROUTILS.setTypeID( ImageObject );

module.exports = ImageObject;