diff --git a/README.md b/README.md
index 5597f08a..f0fa2b52 100755
--- a/README.md
+++ b/README.md
@@ -180,7 +180,8 @@ http.createServer(function(request, response) {
 sharp(inputBuffer)
   .resize(200, 300)
   .interpolateWith(sharp.interpolator.nohalo)
-  .embedWhite()
+  .background('white')
+  .embed()
   .toFile('output.tiff')
   .then(function() {
     // output.tiff is a 200 pixels wide and 300 pixels high image
@@ -190,20 +191,29 @@ sharp(inputBuffer)
 ```
 
 ```javascript
-sharp('input.gif').resize(200, 300).embedBlack().webp().toBuffer(function(err, outputBuffer) {
-  if (err) {
-    throw err;
-  }
-  // outputBuffer contains WebP image data of a 200 pixels wide and 300 pixels high
-  // containing a scaled version, embedded on a black canvas, of input.gif
-});
+sharp('input.gif')
+  .resize(200, 300)
+  .background({r: 0, g: 0, b: 0, a: 0})
+  .embed()
+  .webp()
+  .toBuffer(function(err, outputBuffer) {
+    if (err) {
+      throw err;
+    }
+    // outputBuffer contains WebP image data of a 200 pixels wide and 300 pixels high
+    // containing a scaled version, embedded on a transparent canvas, of input.gif
+  });
 ```
 
 ```javascript
-sharp(inputBuffer).resize(200, 200).max().jpeg().toBuffer().then(function(outputBuffer) {
-  // outputBuffer contains JPEG image data no wider than 200 pixels and no higher
-  // than 200 pixels regardless of the inputBuffer image dimensions
-});
+sharp(inputBuffer)
+  .resize(200, 200)
+  .max()
+  .jpeg()
+  .toBuffer().then(function(outputBuffer) {
+    // outputBuffer contains JPEG image data no wider than 200 pixels and no higher
+    // than 200 pixels regardless of the inputBuffer image dimensions
+  });
 ```
 
 ## API
@@ -234,6 +244,7 @@ Fast access to image metadata without decoding any compressed image data.
 * `height`: Number of pixels high
 * `space`: Name of colour space interpretation e.g. `srgb`, `rgb`, `scrgb`, `cmyk`, `lab`, `xyz`, `b-w` [...](https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L502)
 * `channels`: Number of bands e.g. `3` for sRGB, `4` for CMYK
+* `hasAlpha`: Boolean indicating the presence of an alpha transparency channel
 * `orientation`: Number value of the EXIF Orientation header, if present
 
 A Promises/A+ promise is returned when `callback` is not provided.
@@ -244,10 +255,6 @@ An advanced setting that switches the libvips access method to `VIPS_ACCESS_SEQU
 
 ### Image transformation options
 
-#### background(color) or background(r, g, b)
-
-Set background color for operations such as `flatten`. Pass any valid CSS color as `color` string, e.g. `'#00ff00'`, `'hsl(120,100%,50%)'`, etc., or as numbers in the range of `[0, 255]` for `r`, `g`, and `b`. Defaults color to black.
-
 #### resize(width, [height])
 
 Scale output to `width` x `height`. By default, the resized image is cropped to the exact size specified.
@@ -266,21 +273,29 @@ Possible values are `north`, `east`, `south`, `west`, `center` and `centre`. The
 
 #### max()
 
-Preserving aspect ratio, resize the image to the maximum width or height specified.
+Preserving aspect ratio, resize the image to the maximum `width` or `height` specified.
 
 Both `width` and `height` must be provided via `resize` otherwise the behaviour will default to `crop`.
 
-#### embedWhite()
+#### background(rgba)
 
-Embed the resized image on a white background of the exact size specified.
+Set the background for the `embed` and `flatten` operations.
 
-#### embedBlack()
+`rgba` is parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.
 
-Embed the resized image on a black background of the exact size specified.
+The alpha value is a float between `0` (transparent) and `1` (opaque).
+
+The default background is `{r: 0, g: 0, b: 0, a: 1}`, black without transparency.
+
+#### embed()
+
+Preserving aspect ratio, resize the image to the maximum `width` or `height` specified then embed on a background of the exact `width` and `height` specified.
+
+If the background contains an alpha value then WebP and PNG format output images will contain an alpha channel, even when the input image does not.
 
 #### flatten()
 
-Flatten transparent images onto background with a color set using `background`.
+Merge alpha transparency channel, if any, with `background`.
 
 #### rotate([angle])
 
@@ -327,7 +342,7 @@ JPEG input images will not take advantage of the shrink-on-load performance opti
 
 Convert to 8-bit greyscale; 256 shades of grey.
 
-This is a linear operation. If the input image is in a non-linear colourspace such as sRGB, use `gamma()` with `greyscale()` for the best results.
+This is a linear operation. If the input image is in a non-linear colour space such as sRGB, use `gamma()` with `greyscale()` for the best results.
 
 The output image will still be web-friendly sRGB and contain three (identical) channels.
 
diff --git a/index.js b/index.js
index 3a34641c..380199aa 100755
--- a/index.js
+++ b/index.js
@@ -1,10 +1,12 @@
 /*jslint node: true */
 'use strict';
 
-var Color = require('color');
 var util = require('util');
 var stream = require('stream');
+
+var color = require('color');
 var Promise = require('bluebird');
+
 var sharp = require('./build/Release/sharp');
 
 var Sharp = function(input) {
@@ -13,30 +15,30 @@ var Sharp = function(input) {
   }
   stream.Duplex.call(this);
   this.options = {
+    // input options
+    streamIn: false,
+    sequentialRead: false,
+    // resize options
     width: -1,
     height: -1,
     canvas: 'c',
     gravity: 0,
     angle: 0,
     withoutEnlargement: false,
-    sharpen: false,
     interpolator: 'bilinear',
+    // operations
+    background: [0, 0, 0, 255],
+    flatten: false,
+    sharpen: false,
     gamma: 0,
     greyscale: false,
+    // output options
+    output: '__input',
     progressive: false,
-    sequentialRead: false,
     quality: 80,
     compressionLevel: 6,
-    streamIn: false,
     streamOut: false,
-    withMetadata: false,
-    output: '__input',
-    // background
-    backgroundRed: 0,
-    backgroundGreen: 0,
-    backgroundBlue: 0,
-    // flatten
-    flatten: false
+    withMetadata: false
   };
   if (typeof input === 'string') {
     // input=file
@@ -86,34 +88,6 @@ Sharp.prototype._write = function(chunk, encoding, callback) {
 // Crop this part of the resized image (Center/Centre, North, East, South, West)
 module.exports.gravity = {'center': 0, 'centre': 0, 'north': 1, 'east': 2, 'south': 3, 'west': 4};
 
-Sharp.prototype.background = function(color) {
-  if (arguments.length !== 1 && arguments.length !== 3) {
-    throw new Error('Invalid color. Expected `color` or `r, g, b`');
-  }
-
-  var normalize = function (name, color) {
-    if (isNaN(color) || color < 0 || 255 < color) {
-      throw new Error('Invalid ' + name + ' value (0.0 to 255.0) ' + color);
-    }
-    return color;
-  };
-
-  if (arguments.length === 1) {
-    var channels = Color(color);
-    this.options.backgroundRed = normalize('red', channels.red());
-    this.options.backgroundGreen = normalize('green', channels.green());
-    this.options.backgroundBlue = normalize('blue', channels.blue());
-  } else if (arguments.length === 3) {
-    this.options.backgroundRed = normalize('red', arguments[0]);
-    this.options.backgroundGreen = normalize('green', arguments[1]);
-    this.options.backgroundBlue = normalize('blue', arguments[2]);
-  } else {
-    throw new Error('Unreachable state');
-  }
-
-  return this;
-};
-
 Sharp.prototype.crop = function(gravity) {
   this.options.canvas = 'c';
   if (typeof gravity !== 'undefined') {
@@ -127,18 +101,30 @@ Sharp.prototype.crop = function(gravity) {
   return this;
 };
 
-Sharp.prototype.embedWhite = function() {
-  this.options.canvas = 'w';
+/*
+  Deprecated embed* methods, to be removed in v0.8.0
+*/
+Sharp.prototype.embedWhite = util.deprecate(function() {
+  return this.background('white').embed();
+}, "embedWhite() is deprecated, use background('white').embed() instead");
+Sharp.prototype.embedBlack = util.deprecate(function() {
+  return this.background('black').embed();
+}, "embedBlack() is deprecated, use background('black').embed() instead");
+
+/*
+  Set the background colour for embed and flatten operations.
+  Delegates to the 'Color' module, which can throw an Error
+  but is liberal in what it accepts, clamping values to sensible min/max.
+*/
+Sharp.prototype.background = function(rgba) {
+  var colour = color(rgba);
+  this.options.background = colour.rgbArray();
+  this.options.background.push(colour.alpha() * 255);
   return this;
 };
 
-Sharp.prototype.embedBlack = function() {
-  this.options.canvas = 'b';
-  return this;
-};
-
-Sharp.prototype.flatten = function(background) {
-  this.options.flatten = true;
+Sharp.prototype.embed = function() {
+  this.options.canvas = 'e';
   return this;
 };
 
@@ -147,6 +133,11 @@ Sharp.prototype.max = function() {
   return this;
 };
 
+Sharp.prototype.flatten = function(flatten) {
+  this.options.flatten = (typeof flatten === 'boolean') ? flatten : true;
+  return this;
+};
+
 /*
   Rotate output image by 0, 90, 180 or 270 degrees
   Auto-rotation based on the EXIF Orientation tag is represented by an angle of -1
@@ -193,19 +184,6 @@ Sharp.prototype.interpolateWith = function(interpolator) {
   return this;
 };
 
-/*
-  Deprecated interpolation methods, to be removed in v0.7.0
-*/
-Sharp.prototype.bilinearInterpolation = util.deprecate(function() {
-  return this.interpolateWith(module.exports.interpolator.bilinear);
-}, 'bilinearInterpolation() is deprecated, use interpolateWith(sharp.interpolator.bilinear) instead');
-Sharp.prototype.bicubicInterpolation = util.deprecate(function() {
-  return this.interpolateWith(module.exports.interpolator.bicubic);
-}, 'bicubicInterpolation() is deprecated, use interpolateWith(sharp.interpolator.bicubic) instead');
-Sharp.prototype.nohaloInterpolation = util.deprecate(function() {
-  return this.interpolateWith(module.exports.interpolator.nohalo);
-}, 'nohaloInterpolation() is deprecated, use interpolateWith(sharp.interpolator.nohalo) instead');
-
 /*
   Darken image pre-resize (1/gamma) and brighten post-resize (gamma).
   Improves brightness of resized image in non-linear colour spaces.
@@ -319,31 +297,16 @@ Sharp.prototype.toBuffer = function(callback) {
 
 Sharp.prototype.jpeg = function() {
   this.options.output = '__jpeg';
-  if (arguments.length > 0) {
-    console.error('Use of the jpeg() method with a callback is deprecated in 0.6.x and will be removed in 0.7.x');
-    console.error('Please add toFile(), toBuffer() or Stream methods e.g. pipe() for JPEG output');
-    this._sharp(arguments);
-  }
   return this;
 };
 
 Sharp.prototype.png = function() {
   this.options.output = '__png';
-  if (arguments.length > 0) {
-    console.error('Use of the png() method with a callback is deprecated in 0.6.x and will be removed in 0.7.x');
-    console.error('Please add toFile(), toBuffer() or Stream methods e.g. pipe() for PNG output');
-    this._sharp(arguments);
-  }
   return this;
 };
 
 Sharp.prototype.webp = function() {
   this.options.output = '__webp';
-  if (arguments.length > 0) {
-    console.error('Use of the webp() method with a callback is deprecated in 0.6.x and will be removed in 0.7.x');
-    console.error('Please add toFile(), toBuffer() or Stream methods e.g. pipe() for WebP output');
-    this._sharp(arguments);
-  }
   return this;
 };
 
diff --git a/package.json b/package.json
index 72884aeb..414326f3 100755
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "sharp",
-  "version": "0.6.2",
+  "version": "0.7.0",
   "author": "Lovell Fuller <npm@lovell.info>",
   "contributors": [
     "Pierre Inglebert <pierre.inglebert@gmail.com>",
@@ -38,13 +38,13 @@
     "stream"
   ],
   "dependencies": {
-    "bluebird": "^2.3.2",
+    "bluebird": "^2.3.4",
     "color": "^0.7.1",
     "nan": "^1.3.0"
   },
   "devDependencies": {
     "imagemagick": "^0.1.3",
-    "imagemagick-native": "^1.2.2",
+    "imagemagick-native": "^1.3.0",
     "gm": "^1.16.0",
     "async": "^0.9.0",
     "benchmark": "^1.0.0"
diff --git a/src/sharp.cc b/src/sharp.cc
index a3956b46..c8c75a05 100755
--- a/src/sharp.cc
+++ b/src/sharp.cc
@@ -11,6 +11,12 @@
 using namespace v8;
 using namespace node;
 
+typedef enum {
+  CROP,
+  MAX,
+  EMBED
+} Canvas;
+
 struct resize_baton {
   std::string file_in;
   void* buffer_in;
@@ -21,47 +27,37 @@ struct resize_baton {
   size_t buffer_out_len;
   int width;
   int height;
-  bool crop;
+  Canvas canvas;
   int gravity;
-  bool max;
-  VipsExtend extend;
-  bool sharpen;
   std::string interpolator;
+  double background[4];
+  bool flatten;
+  bool sharpen;
   double gamma;
   bool greyscale;
   bool progressive;
   bool without_enlargement;
   VipsAccess access_method;
   int quality;
-  int compressionLevel;
+  int compression_level;
   int angle;
   std::string err;
-  bool withMetadata;
-  // background
-  double background_red;
-  double background_green;
-  double background_blue;
-  // flatten
-  bool flatten;
+  bool with_metadata;
 
   resize_baton():
     buffer_in_len(0),
     output_format(""),
     buffer_out_len(0),
-    crop(false),
+    canvas(CROP),
     gravity(0),
-    max(false),
+    background{0.0, 0.0, 0.0, 255.0},
+    flatten(false),
     sharpen(false),
     gamma(0.0),
+    greyscale(false),
     progressive(false),
     without_enlargement(false),
-    withMetadata(false),
-    // background
-    background_red(0.0),
-    background_green(0.0),
-    background_blue(0.0),
-    // flatten
-    flatten(false) {}
+    with_metadata(false) {}
 };
 
 typedef enum {
@@ -175,7 +171,7 @@ sharp_calc_crop(int const inWidth, int const inHeight, int const outWidth, int c
 
 /*
   Does this image have an alpha channel?
-  Uses colourspace interpretation with number of channels to guess this.
+  Uses colour space interpretation with number of channels to guess this.
 */
 static bool
 sharp_image_has_alpha(VipsImage *image) {
@@ -427,9 +423,9 @@ class ResizeWorker : public NanAsyncWorker {
       // Fixed width and height
       double xfactor = static_cast<double>(inputWidth) / static_cast<double>(baton->width);
       double yfactor = static_cast<double>(inputHeight) / static_cast<double>(baton->height);
-      factor = baton->crop ? std::min(xfactor, yfactor) : std::max(xfactor, yfactor);
+      factor = (baton->canvas == CROP) ? std::min(xfactor, yfactor) : std::max(xfactor, yfactor);
       // if max is set, we need to compute the real size of the thumb image
-      if (baton->max) {
+      if (baton->canvas == MAX) {
         if (xfactor > yfactor) {
           baton->height = round(static_cast<double>(inputHeight) / xfactor);
         } else {
@@ -502,22 +498,21 @@ class ResizeWorker : public NanAsyncWorker {
     }
     g_object_unref(in);
 
-    // Flatten
+    // Flatten image to remove alpha channel
     VipsImage *flattened = vips_image_new();
-    // We skip non-four-band images as we haven’t tested two-channel PNGs with
-    // alpha channel (yet).
-    // See: https://github.com/lovell/sharp/pull/91#issuecomment-56496548
-    if (baton->flatten && sharp_image_has_alpha(shrunk_on_load) && shrunk_on_load->Bands == 4) {
+    if (baton->flatten && sharp_image_has_alpha(shrunk_on_load)) {
+      // Background colour
       VipsArrayDouble *background = vips_array_double_newv(
-        3, // vector size
-        baton->background_red,
-        baton->background_green,
-        baton->background_blue
+        3, // Ignore alpha channel as we're about to remove it
+        baton->background[0],
+        baton->background[1],
+        baton->background[2]
       );
-
       if (vips_flatten(shrunk_on_load, &flattened, "background", background, NULL)) {
+        vips_area_unref(reinterpret_cast<VipsArea*>(background));
         return resize_error(baton, shrunk_on_load);
       };
+      vips_area_unref(reinterpret_cast<VipsArea*>(background));
     } else {
       vips_copy(shrunk_on_load, &flattened, NULL);
     }
@@ -536,11 +531,11 @@ class ResizeWorker : public NanAsyncWorker {
     // Convert to greyscale (linear, therefore after gamma encoding, if any)
     if (baton->greyscale) {
       VipsImage *greyscale = vips_image_new();
-      if (vips_colourspace(shrunk_on_load, &greyscale, VIPS_INTERPRETATION_B_W, NULL)) {
-        return resize_error(baton, shrunk_on_load);
+      if (vips_colourspace(flattened, &greyscale, VIPS_INTERPRETATION_B_W, NULL)) {
+        return resize_error(baton, flattened);
       }
-      g_object_unref(shrunk_on_load);
-      shrunk_on_load = greyscale;
+      g_object_unref(flattened);
+      flattened = greyscale;
     }
 
     VipsImage *shrunk = vips_image_new();
@@ -560,10 +555,10 @@ class ResizeWorker : public NanAsyncWorker {
       }
       double residualx = static_cast<double>(baton->width) / static_cast<double>(shrunkWidth);
       double residualy = static_cast<double>(baton->height) / static_cast<double>(shrunkHeight);
-      if (baton->crop || baton->max) {
-        residual = std::max(residualx, residualy);
-      } else {
+      if (baton->canvas == EMBED) {
         residual = std::min(residualx, residualy);
+      } else {
+        residual = std::max(residualx, residualy);
       }
     } else {
       vips_copy(flattened, &shrunk, NULL);
@@ -600,7 +595,56 @@ class ResizeWorker : public NanAsyncWorker {
     // Crop/embed
     VipsImage *canvased = vips_image_new();
     if (rotated->Xsize != baton->width || rotated->Ysize != baton->height) {
-      if (baton->crop || baton->max) {
+      if (baton->canvas == EMBED) {
+        // Add non-transparent alpha channel, if required
+        if (baton->background[3] < 255.0 && !sharp_image_has_alpha(rotated)) {
+          // Create single-channel transparency
+          VipsImage *black = vips_image_new();
+          if (vips_black(&black, rotated->Xsize, rotated->Ysize, "bands", 1, NULL)) {
+            g_object_unref(black);
+            return resize_error(baton, rotated);
+          }
+          // Invert to become non-transparent
+          VipsImage *alphaChannel = vips_image_new();
+          if (vips_invert(black, &alphaChannel, NULL)) {
+            g_object_unref(black);
+            g_object_unref(alphaChannel);
+            return resize_error(baton, rotated);
+          }
+          g_object_unref(black);
+          // Append alpha channel to existing image
+          VipsImage *joined = vips_image_new();
+          if (vips_bandjoin2(rotated, alphaChannel, &joined, NULL)) {
+            g_object_unref(alphaChannel);
+            g_object_unref(joined);
+            return resize_error(baton, rotated);
+          }
+          g_object_unref(alphaChannel);
+          g_object_unref(rotated);
+          rotated = joined;
+        }
+        // Create background
+        VipsArrayDouble *background;
+        if (baton->background[3] < 255.0) {
+          background = vips_array_double_newv(
+            4, baton->background[0], baton->background[1], baton->background[2], baton->background[3]
+          );
+        } else {
+          background = vips_array_double_newv(
+            3, baton->background[0], baton->background[1], baton->background[2]
+          );
+        }
+        // Embed
+        int left = (baton->width - rotated->Xsize) / 2;
+        int top = (baton->height - rotated->Ysize) / 2;
+        if (vips_embed(rotated, &canvased, left, top, baton->width, baton->height,
+          "extend", VIPS_EXTEND_BACKGROUND, "background", background, NULL
+        )) {
+          vips_area_unref(reinterpret_cast<VipsArea*>(background));
+          return resize_error(baton, rotated);
+        }
+        vips_area_unref(reinterpret_cast<VipsArea*>(background));
+      } else {
         // Crop/max
         int left;
         int top;
@@ -610,13 +654,6 @@ class ResizeWorker : public NanAsyncWorker {
         if (vips_extract_area(rotated, &canvased, left, top, width, height, NULL)) {
           return resize_error(baton, rotated);
         }
-      } else {
-        // Embed
-        int left = (baton->width - rotated->Xsize) / 2;
-        int top = (baton->height - rotated->Ysize) / 2;
-        if (vips_embed(rotated, &canvased, left, top, baton->width, baton->height, "extend", baton->extend, NULL)) {
-          return resize_error(baton, rotated);
-        }
       }
     } else {
       vips_copy(rotated, &canvased, NULL);
@@ -671,21 +708,21 @@ class ResizeWorker : public NanAsyncWorker {
     VipsImage *output = cached;
     if (baton->output == "__jpeg" || (baton->output == "__input" && inputImageType == JPEG)) {
       // Write JPEG to buffer
-      if (vips_jpegsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", !baton->withMetadata,
+      if (vips_jpegsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", !baton->with_metadata,
         "Q", baton->quality, "optimize_coding", TRUE, "interlace", baton->progressive, NULL)) {
         return resize_error(baton, output);
       }
       baton->output_format = "jpeg";
     } else if (baton->output == "__png" || (baton->output == "__input" && inputImageType == PNG)) {
       // Write PNG to buffer
-      if (vips_pngsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", !baton->withMetadata,
-        "compression", baton->compressionLevel, "interlace", baton->progressive, NULL)) {
+      if (vips_pngsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", !baton->with_metadata,
+        "compression", baton->compression_level, "interlace", baton->progressive, NULL)) {
         return resize_error(baton, output);
       }
       baton->output_format = "png";
     } else if (baton->output == "__webp" || (baton->output == "__input" && inputImageType == WEBP)) {
       // Write WEBP to buffer
-      if (vips_webpsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", !baton->withMetadata,
+      if (vips_webpsave_buffer(output, &baton->buffer_out, &baton->buffer_out_len, "strip", !baton->with_metadata,
         "Q", baton->quality, NULL)) {
         return resize_error(baton, output);
       }
@@ -698,28 +735,28 @@ class ResizeWorker : public NanAsyncWorker {
       bool match_input = !(output_jpeg || output_png || output_webp || output_tiff);
       if (output_jpeg || (match_input && inputImageType == JPEG)) {
         // Write JPEG to file
-        if (vips_jpegsave(output, baton->output.c_str(), "strip", !baton->withMetadata,
+        if (vips_jpegsave(output, baton->output.c_str(), "strip", !baton->with_metadata,
           "Q", baton->quality, "optimize_coding", TRUE, "interlace", baton->progressive, NULL)) {
           return resize_error(baton, output);
         }
         baton->output_format = "jpeg";
       } else if (output_png || (match_input && inputImageType == PNG)) {
         // Write PNG to file
-        if (vips_pngsave(output, baton->output.c_str(), "strip", !baton->withMetadata,
-          "compression", baton->compressionLevel, "interlace", baton->progressive, NULL)) {
+        if (vips_pngsave(output, baton->output.c_str(), "strip", !baton->with_metadata,
+          "compression", baton->compression_level, "interlace", baton->progressive, NULL)) {
           return resize_error(baton, output);
         }
         baton->output_format = "png";
       } else if (output_webp || (match_input && inputImageType == WEBP)) {
         // Write WEBP to file
-        if (vips_webpsave(output, baton->output.c_str(), "strip", !baton->withMetadata,
+        if (vips_webpsave(output, baton->output.c_str(), "strip", !baton->with_metadata,
           "Q", baton->quality, NULL)) {
           return resize_error(baton, output);
         }
         baton->output_format = "webp";
       } else if (output_tiff || (match_input && inputImageType == TIFF)) {
         // Write TIFF to file
-        if (vips_tiffsave(output, baton->output.c_str(), "strip", !baton->withMetadata,
+        if (vips_tiffsave(output, baton->output.c_str(), "strip", !baton->with_metadata,
           "compression", VIPS_FOREIGN_TIFF_COMPRESSION_JPEG, "Q", baton->quality, NULL)) {
           return resize_error(baton, output);
         }
@@ -785,6 +822,7 @@ NAN_METHOD(resize) {
 
   // Input filename
   baton->file_in = *String::Utf8Value(options->Get(NanNew<String>("fileIn"))->ToString());
+  baton->access_method = options->Get(NanNew<String>("sequentialRead"))->BooleanValue() ? VIPS_ACCESS_SEQUENTIAL : VIPS_ACCESS_RANDOM;
   // Input Buffer object
   if (options->Get(NanNew<String>("bufferIn"))->IsObject()) {
     Local<Object> buffer = options->Get(NanNew<String>("bufferIn"))->ToObject();
@@ -794,40 +832,35 @@ NAN_METHOD(resize) {
   // Output image dimensions
   baton->width = options->Get(NanNew<String>("width"))->Int32Value();
   baton->height = options->Get(NanNew<String>("height"))->Int32Value();
-  // Canvas options
+  // Canvas option
   Local<String> canvas = options->Get(NanNew<String>("canvas"))->ToString();
   if (canvas->Equals(NanNew<String>("c"))) {
-    baton->crop = true;
-  } else if (canvas->Equals(NanNew<String>("w"))) {
-    baton->extend = VIPS_EXTEND_WHITE;
-  } else if (canvas->Equals(NanNew<String>("b"))) {
-    baton->extend = VIPS_EXTEND_BLACK;
+    baton->canvas = CROP;
   } else if (canvas->Equals(NanNew<String>("m"))) {
-    baton->max = true;
+    baton->canvas = MAX;
+  } else if (canvas->Equals(NanNew<String>("e"))) {
+    baton->canvas = EMBED;
   }
-
-  // Flatten
-  baton->flatten = options->Get(NanNew<String>("flatten"))->BooleanValue();
-
-  // Background
-  baton->background_red = options->Get(NanNew<String>("backgroundRed"))->NumberValue();
-  baton->background_green = options->Get(NanNew<String>("backgroundGreen"))->NumberValue();
-  baton->background_blue = options->Get(NanNew<String>("backgroundBlue"))->NumberValue();
-
-  // Other options
+  // Background colour
+  Local<Array> background = Local<Array>::Cast(options->Get(NanNew<String>("background")));
+  for (int i = 0; i < 4; i++) {
+    baton->background[i] = background->Get(i)->NumberValue();
+  }
+  // Resize options
+  baton->without_enlargement = options->Get(NanNew<String>("withoutEnlargement"))->BooleanValue();
   baton->gravity = options->Get(NanNew<String>("gravity"))->Int32Value();
-  baton->sharpen = options->Get(NanNew<String>("sharpen"))->BooleanValue();
   baton->interpolator = *String::Utf8Value(options->Get(NanNew<String>("interpolator"))->ToString());
+  // Operators
+  baton->flatten = options->Get(NanNew<String>("flatten"))->BooleanValue();
+  baton->sharpen = options->Get(NanNew<String>("sharpen"))->BooleanValue();
   baton->gamma = options->Get(NanNew<String>("gamma"))->NumberValue();
   baton->greyscale = options->Get(NanNew<String>("greyscale"))->BooleanValue();
-  baton->progressive = options->Get(NanNew<String>("progressive"))->BooleanValue();
-  baton->without_enlargement = options->Get(NanNew<String>("withoutEnlargement"))->BooleanValue();
-  baton->access_method = options->Get(NanNew<String>("sequentialRead"))->BooleanValue() ? VIPS_ACCESS_SEQUENTIAL : VIPS_ACCESS_RANDOM;
-  baton->quality = options->Get(NanNew<String>("quality"))->Int32Value();
-  baton->compressionLevel = options->Get(NanNew<String>("compressionLevel"))->Int32Value();
   baton->angle = options->Get(NanNew<String>("angle"))->Int32Value();
-  baton->withMetadata = options->Get(NanNew<String>("withMetadata"))->BooleanValue();
-
+  // Output options
+  baton->progressive = options->Get(NanNew<String>("progressive"))->BooleanValue();
+  baton->quality = options->Get(NanNew<String>("quality"))->Int32Value();
+  baton->compression_level = options->Get(NanNew<String>("compressionLevel"))->Int32Value();
+  baton->with_metadata = options->Get(NanNew<String>("withMetadata"))->BooleanValue();
   // Output filename or __format for Buffer
   baton->output = *String::Utf8Value(options->Get(NanNew<String>("output"))->ToString());
 
diff --git a/tests/leak.sh b/tests/leak.sh
index 0ba05714..71972a9a 100755
--- a/tests/leak.sh
+++ b/tests/leak.sh
@@ -4,4 +4,4 @@ if ! type valgrind >/dev/null; then
 fi
 
 curl -O https://raw.githubusercontent.com/jcupitt/libvips/master/libvips.supp
-G_SLICE=always-malloc G_DEBUG=gc-friendly valgrind --suppressions=libvips.supp --suppressions=sharp.supp --leak-check=full --show-leak-kinds=definite,indirect,possible node unit.js
+G_SLICE=always-malloc G_DEBUG=gc-friendly valgrind --suppressions=libvips.supp --suppressions=sharp.supp --leak-check=full --show-leak-kinds=definite,indirect,possible --num-callers=20 node unit.js
diff --git a/tests/unit.js b/tests/unit.js
index 96679d43..953ff576 100755
--- a/tests/unit.js
+++ b/tests/unit.js
@@ -94,6 +94,45 @@ async.series([
       done();
     });
   },
+  // Embed - JPEG within PNG, no alpha channel
+  function(done) {
+    sharp(inputJpg)
+      .embed()
+      .resize(320, 240)
+      .png()
+      .toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual('png', info.format);
+        assert.strictEqual(320, info.width);
+        assert.strictEqual(240, info.height);
+        sharp(data).metadata(function(err, metadata) {
+          if (err) throw err;
+          assert.strictEqual(3, metadata.channels);
+          done();
+        });
+      });
+  },
+  // Embed - JPEG within WebP, to include alpha channel
+  function(done) {
+    sharp(inputJpg)
+      .resize(320, 240)
+      .background({r: 0, g: 0, b: 0, a: 0})
+      .embed()
+      .webp()
+      .toBuffer(function(err, data, info) {
+        if (err) throw err;
+        assert.strictEqual(true, data.length > 0);
+        assert.strictEqual('webp', info.format);
+        assert.strictEqual(320, info.width);
+        assert.strictEqual(240, info.height);
+        sharp(data).metadata(function(err, metadata) {
+          if (err) throw err;
+          assert.strictEqual(4, metadata.channels);
+          done();
+        });
+      });
+  },
   // Quality
   function(done) {
     sharp(inputJpg).resize(320, 240).quality(70).toBuffer(function(err, buffer70) {
@@ -110,7 +149,7 @@ async.series([
   },
   // TIFF with dimensions known to cause rounding errors
   function(done) {
-    sharp(inputTiff).resize(240, 320).embedBlack().jpeg().toBuffer(function(err, data, info) {
+    sharp(inputTiff).resize(240, 320).embed().jpeg().toBuffer(function(err, data, info) {
       if (err) throw err;
       assert.strictEqual(true, data.length > 0);
       assert.strictEqual('jpeg', info.format);
@@ -776,22 +815,15 @@ async.series([
       done();
     });
   },
-  function(done) {
-    // Invalid `background` arguments
-    try {
-      sharp(inputPngWithTransparency).background(-1, -1, -1).flatten();
-    } catch (e) {
-      assert.strictEqual(e.message, "Invalid red value (0.0 to 255.0) -1");
-      done();
-      return;
-    }
-    assert.fail();
-  },
   // Verify internal counters
   function(done) {
     var counters = sharp.counters();
     assert.strictEqual(0, counters.queue);
     assert.strictEqual(0, counters.process);
+  },
+  // Empty cache
+  function(done) {
+    sharp.cache(0);
     done();
   }
 ]);