Add support for WebP and TIFF image formats. Closes #7.

README.md

@@ -7,10 +7,12 @@ _adj_
 3. shrewd or astute: a sharp bargainer. 
 4. (Informal.) very stylish: a sharp dresser; a sharp jacket. 
 
-The typical use case for this high speed Node.js module is to convert large JPEG and PNG images to smaller JPEG and PNG images of varying dimensions.
+The typical use case for this high speed Node.js module is to convert large JPEG, PNG, WebP and TIFF images to smaller images of varying dimensions.
 
 The performance of JPEG resizing is typically 15x-25x faster than ImageMagick and GraphicsMagick, based mainly on the number of CPU cores available.
 
+This module supports reading and writing images to and from both the filesystem and Buffer objects (TIFF is limited to filesystem only). Everything remains non-blocking thanks to _libuv_.
+
 Under the hood you'll find the blazingly fast [libvips](https://github.com/jcupitt/libvips) image processing library, originally created in 1989 at Birkbeck College and currently maintained by John Cupitt.
 
 ## Prerequisites
@@ -32,9 +34,9 @@ For the sharpest results, please compile libvips from source.
 
 Scale and crop to `width` x `height` calling `callback` when complete.
 
-`input` can either be a filename String or a Buffer. When using a filename libvips will `mmap` the file for improved performance. 
+`input` can either be a filename String or a Buffer.
 
-`output` can either be a filename String or one of `sharp.buffer.jpeg` or `sharp.buffer.png` to pass a Buffer containing image data to `callback`.
+`output` can either be a filename String or one of `sharp.buffer.jpeg`, `sharp.buffer.png` or `sharp.buffer.webp` to pass a Buffer containing JPEG, PNG or WebP image data to `callback`.
 
 `width` is the Number of pixels wide the resultant image should be.
 
@@ -71,7 +73,7 @@ sharp.resize("input.jpg", sharp.buffer.jpeg, 300, 200, {progressive: true}, func
 ```
 
 ```javascript
-sharp.resize("input.jpg", sharp.buffer.png, 300, 200, {sharpen: true}, function(err, buffer) {
+sharp.resize("input.webp", sharp.buffer.png, 300, 200, {sharpen: true}, function(err, buffer) {
   if (err) {
     throw err;
   }
@@ -80,21 +82,21 @@ sharp.resize("input.jpg", sharp.buffer.png, 300, 200, {sharpen: true}, function(
 ```
 
 ```javascript
-sharp.resize(buffer, "output.jpg", 200, 300, {canvas: sharp.canvas.embedWhite}, function(err) {
+sharp.resize(buffer, "output.tiff", 200, 300, {canvas: sharp.canvas.embedWhite}, function(err) {
   if (err) {
     throw err;
   }
-  // output.jpg is a 200 pixels wide and 300 pixels high image containing a scaled version
+  // output.tiff is a 200 pixels wide and 300 pixels high image containing a scaled version
   // of the image data contained in buffer embedded on a white canvas
 });
 ```
 
 ```javascript
-sharp.resize("input.jpg", sharp.buffer.jpeg, 200, 300, {canvas: sharp.canvas.embedBlack}, function(err, buffer) {
+sharp.resize("input.jpg", sharp.buffer.webp, 200, 300, {canvas: sharp.canvas.embedBlack}, function(err, buffer) {
   if (err) {
     throw err;
   }
-  // buffer contains JPEG image data of a 200 pixels wide and 300 pixels high image
+  // buffer contains WebP image data of a 200 pixels wide and 300 pixels high image
   // containing a scaled version of input.png embedded on a black canvas
 });
 ```
@@ -108,10 +110,12 @@ sharp.resize("input.jpg", sharp.buffer.jpeg, 200, 300, {canvas: sharp.canvas.emb
 Test environment:
 
 * AMD Athlon 4 core 3.3GHz 512KB L2 CPU 1333 DDR3
-* libvips 7.37
+* libvips 7.38
 * libjpeg-turbo8 1.3.0
 * libpng 1.6.6
 * zlib1g 1.2.7
+* libwebp 0.3.0
+* libtiff 4.0.2
 
 `-file-buffer` indicates read from file and write to buffer, `-buffer-file` indicates read from buffer and write to file etc.
 
@@ -149,6 +153,21 @@ Test environment:
 * sharp-file-buffer-progressive x 46.35 ops/sec ±0.20% (76 runs sampled)
 * sharp-file-buffer-sequentialRead x 29.02 ops/sec ±0.62% (72 runs sampled)
 
+### WebP
+
+* sharp-buffer-file x 3.30 ops/sec ±117.14% (19 runs sampled)
+* sharp-buffer-buffer x 7.66 ops/sec ±5.83% (43 runs sampled)
+* sharp-file-file x 9.88 ops/sec ±0.98% (52 runs sampled)
+* sharp-file-buffer x 9.95 ops/sec ±0.25% (52 runs sampled)
+* sharp-file-buffer-sharpen x 9.05 ops/sec ±0.36% (48 runs sampled)
+* sharp-file-buffer-sequentialRead x 9.87 ops/sec ±0.98% (52 runs sampled)
+
+### TIFF
+
+* sharp-file-file x 68.24 ops/sec ±5.93% (85 runs sampled)
+* sharp-file-file-sharpen x 50.76 ops/sec ±0.52% (82 runs sampled)
+* sharp-file-file-sequentialRead x 36.37 ops/sec ±0.90% (87 runs sampled)
+
 ## Licence
 
 Copyright 2013, 2014 Lovell Fuller