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diff --git a/lib/output2/assets-inliner.js b/lib/output2/assets-inliner.js
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+var util = require('util');
+var path = require('path');
+var crc = require('crc');
+
+var FolderOutput = require('./folder')();
+var Promise = require('../utils/promise');
+var fs = require('../utils/fs');
+var imagesUtil = require('../utils/images');
+var location = require('../utils/location');
+
+var DEFAULT_ASSETS_FOLDER = 'assets';
+
+/*
+Mixin to inline all the assets in a book:
+    - Outline <svg> tags
+    - Download remote images
+    - Convert .svg images as png
+*/
+
+module.exports = function assetsInliner(Base) {
+    Base = Base || FolderOutput;
+
+    function AssetsInliner() {
+        Base.apply(this, arguments);
+
+        // Map of svg already converted
+        this.svgs = {};
+        this.inlineSvgs = {};
+
+        // Map of images already downloaded
+        this.downloaded = {};
+    }
+    util.inherits(AssetsInliner, Base);
+
+    // Output a SVG buffer as a file
+    AssetsInliner.prototype.onOutputSVG = function(page, svg) {
+        this.log.debug.ln('output svg from', page.path);
+
+        // Convert svg buffer to a png file
+        return this.convertSVGBuffer(svg)
+
+            // Return relative path from the page
+            .then(function(filename) {
+                return page.relative('/' + filename);
+            });
+    };
+
+
+    // Output an image as a file
+    AssetsInliner.prototype.onOutputImage = function(page, src) {
+        var that = this;
+
+        return Promise()
+
+        // Download file if external
+        .then(function() {
+            if (!location.isExternal(src)) return;
+
+            return that.downloadAsset(src)
+            .then(function(_asset) {
+                src = '/' + _asset;
+            });
+
+        })
+        .then(function() {
+            // Resolve src to a relative filepath to the book's root
+            src = page.resolveLocal(src);
+
+            // Already a PNG/JPG/.. ?
+            if (path.extname(src).toLowerCase() != '.svg') {
+                return src;
+            }
+
+            // Convert SVG to PNG
+            return that.convertSVGFile(that.resolve(src));
+        })
+
+        // Return relative path from the page
+        .then(function(filename) {
+            return page.relative(filename);
+        });
+    };
+
+    // Download an asset if not already download; returns the output file
+    AssetsInliner.prototype.downloadAsset = function(src) {
+        if (this.downloaded[src]) return Promise(this.downloaded[src]);
+
+        var that = this;
+        var ext = path.extname(src);
+        var hash = crc.crc32(src).toString(16);
+
+        // Create new file
+        return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + ext)
+        .then(function(filename) {
+            that.downloaded[src] = filename;
+
+            that.log.debug.ln('downloading asset', src);
+            return fs.download(src, that.resolve(filename))
+            .thenResolve(filename);
+        });
+    };
+
+    // Convert a .svg into an .png
+    // Return the output filename for the .png
+    AssetsInliner.prototype.convertSVGFile = function(src) {
+        if (this.svgs[src]) return Promise(this.svgs[src]);
+
+        var that = this;
+        var hash = crc.crc32(src).toString(16);
+
+        // Create new file
+        return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
+        .then(function(filename) {
+            that.svgs[src] = filename;
+
+            return imagesUtil.convertSVGToPNG(src, that.resolve(filename))
+            .thenResolve(filename);
+        });
+    };
+
+    // Convert an inline svg into an .png
+    // Return the output filename for the .png
+    AssetsInliner.prototype.convertSVGBuffer = function(buf) {
+        var that = this;
+        var hash = crc.crc32(buf).toString(16);
+
+        // Already converted?
+        if (this.inlineSvgs[hash]) return Promise(this.inlineSvgs[hash]);
+
+        return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
+        .then(function(filename) {
+            that.inlineSvgs[hash] = filename;
+
+            return imagesUtil.convertSVGBufferToPNG(buf, that.resolve(filename))
+            .thenResolve(filename);
+        });
+    };
+
+    return AssetsInliner;
+};