openseadragon/src/iiiftilesource.js

549 lines
20 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 Framework
* Format: Image API 1.0 - 2.1
*
* @memberof OpenSeadragon
* @extends OpenSeadragon.TileSource
* @see http://iiif.io/api/image/
* @param {String} [options.tileFormat='jpg']
* The extension that will be used when requiring tiles.
*/
$.IIIFTileSource = function( options ){
/* eslint-disable camelcase */
$.extend( true, this, options );
if ( !( this.height && this.width && this['@id'] ) ) {
throw new Error( 'IIIF required parameters not provided.' );
}
options.tileSizePerScaleFactor = {};
this.tileFormat = this.tileFormat || 'jpg';
this.version = options.version;
// N.B. 2.0 renamed scale_factors to scaleFactors
if ( this.tile_width && this.tile_height ) {
options.tileWidth = this.tile_width;
options.tileHeight = this.tile_height;
} else 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.tileWidth = this.tiles[0].width;
// Use height if provided, otherwise assume square tiles and use width.
options.tileHeight = this.tiles[0].height || 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] = {
width: this.tiles[t].width,
height: this.tiles[t].height || this.tiles[t].width
};
}
}
}
} else if ( canBeTiled(options) ) {
// 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;
}
} else if (this.sizes && this.sizes.length > 0) {
// This info.json can't be tiled, but we can still construct a legacy pyramid from the sizes array.
// In this mode, IIIFTileSource will call functions from the abstract baseTileSource or the
// LegacyTileSource instead of performing IIIF tiling.
this.emulateLegacyImagePyramid = true;
options.levels = constructLevels( this );
// use the largest available size to define tiles
$.extend( true, options, {
width: options.levels[ options.levels.length - 1 ].width,
height: options.levels[ options.levels.length - 1 ].height,
tileSize: Math.max( options.height, options.width ),
tileOverlap: 0,
minLevel: 0,
maxLevel: options.levels.length - 1
});
this.levels = options.levels;
} else {
$.console.error("Nothing in the info.json to construct image pyramids from");
}
if (!options.maxLevel && !this.emulateLegacyImagePyramid) {
if (!this.scale_factors) {
options.maxLevel = Number(Math.ceil(Math.log(Math.max(this.width, this.height), 2)));
} else {
var maxScaleFactor = Math.max.apply(null, this.scale_factors);
options.maxLevel = Math.round(Math.log(maxScaleFactor) * Math.LOG2E);
}
}
$.TileSource.apply( this, [ options ] );
};
$.extend( $.IIIFTileSource.prototype, $.TileSource.prototype, /** @lends OpenSeadragon.IIIFTileSource.prototype */{
/**
* Determine if the data and/or url imply the image service is supported by
* this tile source.
* @function
* @param {Object|Array} data
* @param {String} optional - url
*/
supports: function( data, url ) {
// Version 2.0 and forwards
if (data.protocol && data.protocol === 'http://iiif.io/api/image') {
return true;
// Version 1.1
} else if ( data['@context'] && (
data['@context'] === "http://library.stanford.edu/iiif/image-api/1.1/context.json" ||
data['@context'] === "http://iiif.io/api/image/1/context.json") ) {
// N.B. the iiif.io context is wrong, but where the representation lives so likely to be used
return true;
// Version 1.0
} else if ( data.profile &&
data.profile.indexOf("http://library.stanford.edu/iiif/image-api/compliance.html") === 0) {
return true;
} else if ( data.identifier && data.width && data.height ) {
return true;
} else if ( data.documentElement &&
"info" === data.documentElement.tagName &&
"http://library.stanford.edu/iiif/image-api/ns/" ===
data.documentElement.namespaceURI) {
return true;
// Not IIIF
} else {
return false;
}
},
/**
*
* @function
* @param {Object} data - the raw configuration
* @param {String} url - the url configuration was retrieved from
* @param {String} postData - HTTP POST data in k=v&k2=v2... form or null
* @example <caption>IIIF 1.1 Info Looks like this</caption>
* {
* "@context" : "http://library.stanford.edu/iiif/image-api/1.1/context.json",
* "@id" : "http://iiif.example.com/prefix/1E34750D-38DB-4825-A38A-B60A345E591C",
* "width" : 6000,
* "height" : 4000,
* "scale_factors" : [ 1, 2, 4 ],
* "tile_width" : 1024,
* "tile_height" : 1024,
* "formats" : [ "jpg", "png" ],
* "qualities" : [ "native", "grey" ],
* "profile" : "http://library.stanford.edu/iiif/image-api/1.1/compliance.html#level0"
* }
*/
configure: function( data, url, postData ){
// Try to deduce our version and fake it upwards if needed
if ( !$.isPlainObject(data) ) {
var options = configureFromXml10( data );
options['@context'] = "http://iiif.io/api/image/1.0/context.json";
options['@id'] = url.replace('/info.xml', '');
options.version = 1;
return options;
} else {
if ( !data['@context'] ) {
data['@context'] = 'http://iiif.io/api/image/1.0/context.json';
data['@id'] = url.replace('/info.json', '');
data.version = 1;
} else {
var context = data['@context'];
if (Array.isArray(context)) {
for (var i = 0; i < context.length; i++) {
if (typeof context[i] === 'string' &&
( /^http:\/\/iiif\.io\/api\/image\/[1-3]\/context\.json$/.test(context[i]) ||
context[i] === 'http://library.stanford.edu/iiif/image-api/1.1/context.json' ) ) {
context = context[i];
break;
}
}
}
switch (context) {
case 'http://iiif.io/api/image/1/context.json':
case 'http://library.stanford.edu/iiif/image-api/1.1/context.json':
data.version = 1;
break;
case 'http://iiif.io/api/image/2/context.json':
data.version = 2;
break;
case 'http://iiif.io/api/image/3/context.json':
data.version = 3;
break;
default:
$.console.error('Data has a @context property which contains no known IIIF context URI.');
}
}
if ( !data['@id'] && data['id'] ) {
data['@id'] = data['id'];
}
if(data.preferredFormats) {
for (var f = 0; f < data.preferredFormats.length; f++ ) {
if ( OpenSeadragon.imageFormatSupported(data.preferredFormats[f]) ) {
data.tileFormat = data.preferredFormats[f];
break;
}
}
}
return data;
}
},
/**
* Return the tileWidth for the given level.
* @function
* @param {Number} level
*/
getTileWidth: function( level ) {
if(this.emulateLegacyImagePyramid) {
return $.TileSource.prototype.getTileWidth.call(this, level);
}
var scaleFactor = Math.pow(2, this.maxLevel - level);
if (this.tileSizePerScaleFactor && this.tileSizePerScaleFactor[scaleFactor]) {
return this.tileSizePerScaleFactor[scaleFactor].width;
}
return this._tileWidth;
},
/**
* Return the tileHeight for the given level.
* @function
* @param {Number} level
*/
getTileHeight: function( level ) {
if(this.emulateLegacyImagePyramid) {
return $.TileSource.prototype.getTileHeight.call(this, level);
}
var scaleFactor = Math.pow(2, this.maxLevel - level);
if (this.tileSizePerScaleFactor && this.tileSizePerScaleFactor[scaleFactor]) {
return this.tileSizePerScaleFactor[scaleFactor].height;
}
return this._tileHeight;
},
/**
* @function
* @param {Number} level
*/
getLevelScale: function ( level ) {
if(this.emulateLegacyImagePyramid) {
var levelScale = NaN;
if (this.levels.length > 0 && level >= this.minLevel && level <= this.maxLevel) {
levelScale =
this.levels[level].width /
this.levels[this.maxLevel].width;
}
return levelScale;
}
return $.TileSource.prototype.getLevelScale.call(this, level);
},
/**
* @function
* @param {Number} level
*/
getNumTiles: function( level ) {
if(this.emulateLegacyImagePyramid) {
var scale = this.getLevelScale(level);
if (scale) {
return new $.Point(1, 1);
} else {
return new $.Point(0, 0);
}
}
return $.TileSource.prototype.getNumTiles.call(this, level);
},
/**
* @function
* @param {Number} level
* @param {OpenSeadragon.Point} point
*/
getTileAtPoint: function( level, point ) {
if(this.emulateLegacyImagePyramid) {
return new $.Point(0, 0);
}
return $.TileSource.prototype.getTileAtPoint.call(this, level, point);
},
/**
* Responsible for retrieving 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 ){
if(this.emulateLegacyImagePyramid) {
var url = null;
if ( this.levels.length > 0 && level >= this.minLevel && level <= this.maxLevel ) {
url = this.levels[ level ].url;
}
return url;
}
//# 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
tileWidth,
tileHeight,
iiifTileSizeWidth,
iiifTileSizeHeight,
iiifRegion,
iiifTileX,
iiifTileY,
iiifTileW,
iiifTileH,
iiifSize,
iiifSizeW,
iiifSizeH,
iiifQuality,
uri;
tileWidth = this.getTileWidth(level);
tileHeight = this.getTileHeight(level);
iiifTileSizeWidth = Math.ceil( tileWidth / scale );
iiifTileSizeHeight = Math.ceil( tileHeight / scale );
if (this.version === 1) {
iiifQuality = "native." + this.tileFormat;
} else {
iiifQuality = "default." + this.tileFormat;
}
if ( levelWidth < tileWidth && levelHeight < tileHeight ){
if ( this.version === 2 && levelWidth === this.width ) {
iiifSize = "full";
} else if ( this.version === 3 && levelWidth === this.width && levelHeight === this.height ) {
iiifSize = "max";
} else if ( this.version === 3 ) {
iiifSize = levelWidth + "," + levelHeight;
} else {
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 );
if ( x === 0 && y === 0 && iiifTileW === this.width && iiifTileH === this.height ) {
iiifRegion = "full";
} else {
iiifRegion = [ iiifTileX, iiifTileY, iiifTileW, iiifTileH ].join( ',' );
}
iiifSizeW = Math.ceil( iiifTileW * scale );
iiifSizeH = Math.ceil( iiifTileH * scale );
if ( this.version === 2 && iiifSizeW === this.width ) {
iiifSize = "full";
} else if ( this.version === 3 && iiifSizeW === this.width && iiifSizeH === this.height ) {
iiifSize = "max";
} else if (this.version === 3) {
iiifSize = iiifSizeW + "," + iiifSizeH;
} else {
iiifSize = iiifSizeW + ",";
}
}
uri = [ this['@id'], iiifRegion, iiifSize, IIIF_ROTATION, iiifQuality ].join( '/' );
return uri;
},
__testonly__: {
canBeTiled: canBeTiled,
constructLevels: constructLevels
}
});
/**
* Determine whether arbitrary tile requests can be made against a service with the given profile
* @function
* @param {Object} options
* @param {Array|String} options.profile
* @param {Number} options.version
* @param {String} options.extraFeatures
* @returns {Boolean}
*/
function canBeTiled ( options ) {
var level0Profiles = [
"http://library.stanford.edu/iiif/image-api/compliance.html#level0",
"http://library.stanford.edu/iiif/image-api/1.1/compliance.html#level0",
"http://iiif.io/api/image/2/level0.json",
"level0",
"https://iiif.io/api/image/3/level0.json"
];
var profileLevel = Array.isArray(options.profile) ? options.profile[0] : options.profile;
var isLevel0 = (level0Profiles.indexOf(profileLevel) !== -1);
var hasCanoncicalSizeFeature = false;
if ( options.version === 2 && options.profile.length > 1 && options.profile[1].supports ) {
hasCanoncicalSizeFeature = options.profile[1].supports.indexOf( "sizeByW" ) !== -1;
}
if ( options.version === 3 && options.extraFeatures ) {
hasCanoncicalSizeFeature = options.extraFeatures.indexOf( "sizeByWh" ) !== -1;
}
return !isLevel0 || hasCanoncicalSizeFeature;
}
/**
* Build the legacy pyramid URLs (one tile per level)
* @function
* @param {object} options - infoJson
* @throws {Error}
*/
function constructLevels(options) {
var levels = [];
for(var i = 0; i < options.sizes.length; i++) {
levels.push({
url: options['@id'] + '/full/' + options.sizes[i].width + ',' +
(options.version === 3 ? options.sizes[i].height : '') +
'/0/default.' + options.tileFormat,
width: options.sizes[i].width,
height: options.sizes[i].height
});
}
return levels.sort(function(a, b) {
return a.width - b.width;
});
}
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 ));