openseadragon/src/iiiftilesource.js
2014-09-04 12:04:31 -07:00

309 lines
11 KiB
JavaScript

/*
* OpenSeadragon - IIIFTileSource
*
* Copyright (C) 2009 CodePlex Foundation
* Copyright (C) 2010-2013 OpenSeadragon contributors
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of CodePlex Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
(function( $ ){
/**
* @class IIIFTileSource
* @classdesc A client implementation of the International Image Interoperability
* Format: Image API 1.0 - 2.0
*
* @memberof OpenSeadragon
* @extends OpenSeadragon.TileSource
* @see http://iiif.io/api/image/
*/
$.IIIFTileSource = function( options ){
$.extend( true, this, options );
if ( !( this.height && this.width && this['@id'] ) ) {
throw new Error( 'IIIF required parameters not provided.' );
}
options.tileSizePerScaleFactor = {};
// N.B. 2.0 renamed scale_factors to scaleFactors
if ( this.tile_width ) {
options.tileSize = this.tile_width;
} else if ( this.tile_height ) {
options.tileSize = this.tile_height;
} else if ( this.tiles ) {
// Version 2.0 forwards
if ( this.tiles.length == 1 ) {
options.tileSize = this.tiles[0].width;
this.scale_factors = this.tiles[0].scaleFactors;
} else {
// Multiple tile sizes at different levels
this.scale_factors = [];
for (var t = 0; t < this.tiles.length; t++ ) {
for (var sf = 0; sf < this.tiles[t].scaleFactors.length; sf++) {
var scaleFactor = this.tiles[t].scaleFactors[sf];
this.scale_factors.push(scaleFactor);
options.tileSizePerScaleFactor[scaleFactor] = this.tiles[t].width;
}
}
}
} else {
// use the largest of tileOptions that is smaller than the short dimension
var shortDim = Math.min( this.height, this.width ),
tileOptions = [256,512,1024],
smallerTiles = [];
for ( var c = 0; c < tileOptions.length; c++ ) {
if ( tileOptions[c] <= shortDim ) {
smallerTiles.push( tileOptions[c] );
}
}
if ( smallerTiles.length > 0 ) {
options.tileSize = Math.max.apply( null, smallerTiles );
} else {
// If we're smaller than 256, just use the short side.
options.tileSize = shortDim;
}
this.tile_width = options.tileSize; // So that 'full' gets used for
this.tile_height = options.tileSize; // the region below
}
if ( !options.maxLevel ) {
if ( !this.scale_factors ) {
options.maxLevel = Number( Math.ceil( Math.log( Math.max( this.width, this.height ), 2 ) ) );
} else {
options.maxLevel = Math.floor( Math.pow( Math.max.apply(null, this.scale_factors), 0.5) );
}
}
$.TileSource.apply( this, [ options ] );
};
$.extend( $.IIIFTileSource.prototype, $.TileSource.prototype, /** @lends OpenSeadragon.IIIFTileSource.prototype */{
/**
* Determine if the data and/or url imply the image service is supported by
* this tile source.
* @function
* @param {Object|Array} data
* @param {String} optional - url
*/
supports: function( data, url ) {
// Version 2.0 and forwards
if (data.protocol && data.protocol == 'http://iiif.io/api/image') {
return true;
// Version 1.1
} else if ( data['@context'] && (
data['@context'] == "http://library.stanford.edu/iiif/image-api/1.1/context.json" ||
data['@context'] == "http://iiif.io/api/image/1/context.json") ) {
// N.B. the iiif.io context is wrong, but where the representation lives so likely to be used
return true;
// Version 1.0
} else if ( data.profile &&
data.profile.indexOf("http://library.stanford.edu/iiif/image-api/compliance.html") === 0) {
return true;
} else if ( data.identifier && data.width && data.height ) {
return true;
} else if ( data.documentElement &&
"info" == data.documentElement.tagName &&
"http://library.stanford.edu/iiif/image-api/ns/" ==
data.documentElement.namespaceURI) {
return true;
// Not IIIF
} else {
return false;
}
},
/**
*
* @function
* @param {Object} data - the raw configuration
* @example <caption>IIIF 1.1 Info Looks like this</caption>
* {
* "@context" : "http://library.stanford.edu/iiif/image-api/1.1/context.json",
* "@id" : "http://iiif.example.com/prefix/1E34750D-38DB-4825-A38A-B60A345E591C",
* "width" : 6000,
* "height" : 4000,
* "scale_factors" : [ 1, 2, 4 ],
* "tile_width" : 1024,
* "tile_height" : 1024,
* "formats" : [ "jpg", "png" ],
* "qualities" : [ "native", "grey" ],
* "profile" : "http://library.stanford.edu/iiif/image-api/1.1/compliance.html#level0"
* }
*/
configure: function( data, url ){
// Try to deduce our version and fake it upwards if needed
if ( !$.isPlainObject(data) ) {
var options = configureFromXml10( data );
options['@context'] = "http://iiif.io/api/image/1.0/context.json";
options['@id'] = url.replace('/info.xml', '');
return options;
} else if ( !data['@context'] ) {
data['@context'] = 'http://iiif.io/api/image/1.0/context.json';
data['@id'] = url.replace('/info.json', '');
return data;
} else {
return data;
}
},
/**
* Return the tileSize for the given level.
* @function
* @param {Number} level
*/
getTileSize: function( level ){
var scaleFactor = Math.pow(2, this.maxLevel - level);
// cache it in case any external code is going to read it directly
if (this.tileSizePerScaleFactor && this.tileSizePerScaleFactor[scaleFactor]) {
this.tileSize = this.tileSizePerScaleFactor[scaleFactor];
}
return this.tileSize;
},
/**
* Responsible for retreiving the url which will return an image for the
* region specified by the given x, y, and level components.
* @function
* @param {Number} level - z index
* @param {Number} x
* @param {Number} y
* @throws {Error}
*/
getTileUrl: function( level, x, y ){
//# constants
var IIIF_ROTATION = '0',
//## get the scale (level as a decimal)
scale = Math.pow( 0.5, this.maxLevel - level ),
//# image dimensions at this level
levelWidth = Math.ceil( this.width * scale ),
levelHeight = Math.ceil( this.height * scale ),
//## iiif region
iiifTileSizeWidth,
iiifTileSizeHeight,
iiifRegion,
iiifTileX,
iiifTileY,
iiifTileW,
iiifTileH,
iiifSize,
iiifQuality,
uri;
iiifTileSizeWidth = Math.ceil( this.getTileSize(level) / scale );
iiifTileSizeHeight = iiifTileSizeWidth;
if ( this['@context'].indexOf('/1.0/context.json') > -1 ||
this['@context'].indexOf('/1.1/context.json') > -1 ||
this['@context'].indexOf('/1/context.json') > -1 ) {
iiifQuality = "native.jpg";
} else {
iiifQuality = "default.jpg";
}
if ( levelWidth < this.tile_width && levelHeight < this.tile_height ){
iiifSize = levelWidth + ",";
iiifRegion = 'full';
} else {
iiifTileX = x * iiifTileSizeWidth;
iiifTileY = y * iiifTileSizeHeight;
iiifTileW = Math.min( iiifTileSizeWidth, this.width - iiifTileX );
iiifTileH = Math.min( iiifTileSizeHeight, this.height - iiifTileY );
iiifSize = Math.ceil( iiifTileW * scale ) + ",";
iiifRegion = [ iiifTileX, iiifTileY, iiifTileW, iiifTileH ].join( ',' );
}
uri = [ this['@id'], iiifRegion, iiifSize, IIIF_ROTATION, iiifQuality ].join( '/' );
return uri;
}
});
function configureFromXml10(xmlDoc) {
//parse the xml
if ( !xmlDoc || !xmlDoc.documentElement ) {
throw new Error( $.getString( "Errors.Xml" ) );
}
var root = xmlDoc.documentElement,
rootName = root.tagName,
configuration = null;
if ( rootName == "info" ) {
try {
configuration = {};
parseXML10( root, configuration );
return configuration;
} catch ( e ) {
throw (e instanceof Error) ?
e :
new Error( $.getString("Errors.IIIF") );
}
}
throw new Error( $.getString( "Errors.IIIF" ) );
}
function parseXML10( node, configuration, property ) {
var i,
value;
if ( node.nodeType == 3 && property ) {//text node
value = node.nodeValue.trim();
if( value.match(/^\d*$/)){
value = Number( value );
}
if( !configuration[ property ] ){
configuration[ property ] = value;
}else{
if( !$.isArray( configuration[ property ] ) ){
configuration[ property ] = [ configuration[ property ] ];
}
configuration[ property ].push( value );
}
} else if( node.nodeType == 1 ){
for( i = 0; i < node.childNodes.length; i++ ){
parseXML10( node.childNodes[ i ], configuration, node.nodeName );
}
}
}
}( OpenSeadragon ));