Auto merge of #7933 - mbrubeck:piston-image, r=glennw

Replace libpng and stb_image with PistonDevelopers/image

Fixes #3368. r? @glennw 

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components/compositing/Cargo.toml

@@ -52,10 +52,6 @@ git = "https://github.com/servo/rust-azure"
 [dependencies.layers]
 git = "https://github.com/servo/rust-layers"
 
-[dependencies.png]
-git = "https://github.com/servo/rust-png"
-features = [ "serde-serialization" ]
-
 [dependencies.clipboard]
 git = "https://github.com/aweinstock314/rust-clipboard"
 
@@ -72,6 +68,7 @@ features = [ "serde_serialization" ]
 
 [dependencies]
 app_units = "0.1"
+image = "0.3.14"
 log = "0.3"
 num = "0.1.24"
 time = "0.1.17"

components/compositing/compositor.rs

@@ -16,7 +16,8 @@ use gfx::paint_task::{ChromeToPaintMsg, PaintRequest};
 use gfx_traits::color;
 use gleam::gl;
 use gleam::gl::types::{GLint, GLsizei};
-use ipc_channel::ipc;
+use image::{DynamicImage, ImageFormat, RgbImage};
+use ipc_channel::ipc::{self, IpcSharedMemory};
 use ipc_channel::router::ROUTER;
 use layers::geometry::{DevicePixel, LayerPixel};
 use layers::layers::{BufferRequest, Layer, LayerBuffer, LayerBufferSet};
@@ -27,18 +28,18 @@ use layers::scene::Scene;
 use layout_traits::LayoutControlChan;
 use msg::compositor_msg::{Epoch, FrameTreeId, LayerId, LayerKind};
 use msg::compositor_msg::{LayerProperties, ScrollPolicy};
-use msg::constellation_msg::AnimationState;
 use msg::constellation_msg::Msg as ConstellationMsg;
+use msg::constellation_msg::{AnimationState, Image, PixelFormat};
 use msg::constellation_msg::{ConstellationChan, Key, KeyModifiers, KeyState, LoadData};
 use msg::constellation_msg::{NavigationDirection, PipelineId, WindowSizeData};
 use pipeline::CompositionPipeline;
-use png;
 use profile_traits::mem::{self, ReportKind, Reporter, ReporterRequest};
 use profile_traits::time::{self, ProfilerCategory, profile};
 use script_traits::{ConstellationControlMsg, LayoutControlMsg};
 use scrolling::ScrollingTimerProxy;
 use std::collections::hash_map::Entry::{Occupied, Vacant};
 use std::collections::{HashMap, HashSet};
+use std::fs::File;
 use std::mem as std_mem;
 use std::rc::Rc;
 use std::slice::bytes::copy_memory;
@@ -1521,7 +1522,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
     /// for some reason. If CompositeTarget is Window or Png no image data is returned;
     /// in the latter case the image is written directly to a file. If CompositeTarget
     /// is WindowAndPng Ok(Some(png::Image)) is returned.
-    pub fn composite_specific_target(&mut self, target: CompositeTarget) -> Result<Option<png::Image>, ()> {
+    pub fn composite_specific_target(&mut self, target: CompositeTarget) -> Result<Option<Image>, ()> {
 
         if !self.context.is_some() {
             return Err(())
@@ -1573,13 +1574,19 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         let rv = match target {
             CompositeTarget::Window => None,
             CompositeTarget::WindowAndPng => {
-                Some(self.draw_png(framebuffer_ids, texture_ids, width, height))
+                let img = self.draw_img(framebuffer_ids, texture_ids, width, height);
+                Some(Image {
+                    width: img.width(),
+                    height: img.height(),
+                    format: PixelFormat::RGB8,
+                    bytes: IpcSharedMemory::from_bytes(&*img),
+                })
             }
             CompositeTarget::PngFile => {
-                let mut img = self.draw_png(framebuffer_ids, texture_ids, width, height);
+                let img = self.draw_img(framebuffer_ids, texture_ids, width, height);
                 let path = opts::get().output_file.as_ref().unwrap();
-                let res = png::store_png(&mut img, &path);
-                assert!(res.is_ok(), format!("Error writing png: {}", res.unwrap_err()));
+                let mut file = File::create(path).unwrap();
+                DynamicImage::ImageRgb8(img).save(&mut file, ImageFormat::PNG).unwrap();
                 None
             }
         };
@@ -1596,12 +1603,12 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         Ok(rv)
     }
 
-    fn draw_png(&self,
+    fn draw_img(&self,
                 framebuffer_ids: Vec<gl::GLuint>,
                 texture_ids: Vec<gl::GLuint>,
                 width: usize,
                 height: usize)
-                -> png::Image {
+                -> RgbImage {
         let mut pixels = gl::read_pixels(0, 0,
                                          width as gl::GLsizei,
                                          height as gl::GLsizei,
@@ -1622,11 +1629,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
             copy_memory(&src_slice[..stride],
                         &mut pixels[dst_start .. dst_start + stride]);
         }
-        png::Image {
-            width: width as u32,
-            height: height as u32,
-            pixels: png::PixelsByColorType::RGB8(pixels),
-        }
+        RgbImage::from_raw(width as u32, height as u32, pixels).unwrap()
     }
 
     fn composite_if_necessary(&mut self, reason: CompositingReason) {

components/compositing/compositor_task.rs

@@ -13,8 +13,7 @@ use layers::platform::surface::{NativeDisplay, NativeSurface};
 use msg::compositor_msg::{Epoch, FrameTreeId, LayerId, LayerProperties};
 use msg::compositor_msg::{PaintListener, ScriptToCompositorMsg};
 use msg::constellation_msg::{AnimationState, ConstellationChan, PipelineId};
-use msg::constellation_msg::{Key, KeyModifiers, KeyState};
-use png;
+use msg::constellation_msg::{Image, Key, KeyModifiers, KeyState};
 use profile_traits::mem;
 use profile_traits::time;
 use std::fmt::{Debug, Error, Formatter};
@@ -193,7 +192,7 @@ pub enum Msg {
     /// Changes the cursor.
     SetCursor(Cursor),
     /// Composite to a PNG file and return the Image over a passed channel.
-    CreatePng(IpcSender<Option<png::Image>>),
+    CreatePng(IpcSender<Option<Image>>),
     /// Informs the compositor that the paint task for the given pipeline has exited.
     PaintTaskExited(PipelineId),
     /// Alerts the compositor that the viewport has been constrained in some manner

components/compositing/lib.rs

@@ -33,6 +33,7 @@ extern crate euclid;
 extern crate gfx;
 extern crate gfx_traits;
 extern crate gleam;
+extern crate image;
 extern crate ipc_channel;
 extern crate layers;
 extern crate layout_traits;
@@ -40,7 +41,6 @@ extern crate msg;
 extern crate net_traits;
 extern crate num;
 extern crate offscreen_gl_context;
-extern crate png;
 extern crate script_traits;
 extern crate style_traits;
 extern crate time;

components/msg/Cargo.toml

@@ -22,10 +22,6 @@ git = "https://github.com/servo/rust-azure"
 [dependencies.layers]
 git = "https://github.com/servo/rust-layers"
 
-[dependencies.png]
-git = "https://github.com/servo/rust-png"
-features = [ "serde-serialization" ]
-
 [dependencies.hyper]
 version = "0.6"
 features = [ "serde-serialization" ]

components/msg/constellation_msg.rs

@@ -11,10 +11,9 @@ use euclid::scale_factor::ScaleFactor;
 use euclid::size::{Size2D, TypedSize2D};
 use hyper::header::Headers;
 use hyper::method::Method;
-use ipc_channel::ipc::IpcSender;
+use ipc_channel::ipc::{IpcSender, IpcSharedMemory};
 use layers::geometry::DevicePixel;
 use offscreen_gl_context::GLContextAttributes;
-use png::Image;
 use std::cell::Cell;
 use std::collections::HashMap;
 use std::fmt;
@@ -372,7 +371,24 @@ pub enum WebDriverCommandMsg {
     LoadUrl(PipelineId, LoadData, IpcSender<LoadStatus>),
     Refresh(PipelineId, IpcSender<LoadStatus>),
     ScriptCommand(PipelineId, WebDriverScriptCommand),
-    TakeScreenshot(PipelineId, IpcSender<Option<Image>>)
+    TakeScreenshot(PipelineId, IpcSender<Option<Image>>),
+}
+
+#[derive(Deserialize, Eq, PartialEq, Serialize, HeapSizeOf)]
+pub enum PixelFormat {
+    K8,         // Luminance channel only
+    KA8,        // Luminance + alpha
+    RGB8,       // RGB, 8 bits per channel
+    RGBA8,      // RGB + alpha, 8 bits per channel
+}
+
+#[derive(Deserialize, Serialize, HeapSizeOf)]
+pub struct Image {
+    pub width: u32,
+    pub height: u32,
+    pub format: PixelFormat,
+    #[ignore_heap_size_of = "Defined in ipc-channel"]
+    pub bytes: IpcSharedMemory,
 }
 
 /// Similar to net::resource_task::LoadData

components/msg/lib.rs

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#![feature(custom_derive, plugin)]
+#![feature(custom_attribute, custom_derive, plugin)]
 #![plugin(serde_macros, plugins)]
 
 extern crate app_units;
@@ -19,7 +19,6 @@ extern crate io_surface;
 extern crate ipc_channel;
 extern crate layers;
 extern crate offscreen_gl_context;
-extern crate png;
 extern crate rustc_serialize;
 extern crate serde;
 extern crate style_traits;

components/net/Cargo.toml

@@ -19,10 +19,6 @@ path = "../devtools_traits"
 [dependencies.plugins]
 path = "../plugins"
 
-[dependencies.png]
-git = "https://github.com/servo/rust-png"
-features = [ "serde-serialization" ]
-
 [dependencies.hyper]
 version = "0.6"
 features = [ "serde-serialization" ]

components/net/lib.rs

@@ -21,7 +21,6 @@ extern crate hyper;
 extern crate ipc_channel;
 extern crate net_traits;
 extern crate openssl;
-extern crate png;
 extern crate rustc_serialize;
 extern crate time;
 extern crate url;

components/net_traits/Cargo.toml

@@ -7,10 +7,6 @@ authors = ["The Servo Project Developers"]
 name = "net_traits"
 path = "lib.rs"
 
-[dependencies.png]
-git = "https://github.com/servo/rust-png"
-features = [ "serde-serialization" ]
-
 [dependencies.util]
 path = "../util"
 
@@ -37,6 +33,7 @@ path = "../plugins"
 [dependencies]
 log = "0.3"
 euclid = "0.2"
+image = "0.3.14"
 regex = "0.1.33"
 regex_macros = "0.1.19"
 serde = "0.6"

components/net_traits/image/base.rs

@@ -3,32 +3,15 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use ipc_channel::ipc::IpcSharedMemory;
-use png;
+use piston_image::{self, DynamicImage, GenericImage};
 use stb_image::image as stb_image2;
-use std::mem;
-use util::mem::HeapSizeOf;
 use util::vec::byte_swap;
 
+pub use msg::constellation_msg::{Image, PixelFormat};
+
 // FIXME: Images must not be copied every frame. Instead we should atomically
 // reference count them.
 
-#[derive(Deserialize, Serialize, HeapSizeOf)]
-pub enum PixelFormat {
-    K8,         // Luminance channel only
-    KA8,        // Luminance + alpha
-    RGB8,       // RGB, 8 bits per channel
-    RGBA8,      // RGB + alpha, 8 bits per channel
-}
-
-#[derive(Deserialize, Serialize, HeapSizeOf)]
-pub struct Image {
-    pub width: u32,
-    pub height: u32,
-    pub format: PixelFormat,
-    #[ignore_heap_size_of = "Defined in ipc-channel"]
-    pub bytes: IpcSharedMemory,
-}
-
 // TODO(pcwalton): Speed up with SIMD, or better yet, find some way to not do this.
 fn byte_swap_and_premultiply(data: &mut [u8]) {
     let length = data.len();
@@ -48,41 +31,10 @@ pub fn load_from_memory(buffer: &[u8]) -> Option<Image> {
         return None;
     }
 
-    if png::is_png(buffer) {
-        match png::load_png_from_memory(buffer) {
-            Ok(mut png_image) => {
-                let (bytes, format) = match png_image.pixels {
-                    png::PixelsByColorType::K8(ref mut data) => {
-                        (data, PixelFormat::K8)
-                    }
-                    png::PixelsByColorType::KA8(ref mut data) => {
-                        (data, PixelFormat::KA8)
-                    }
-                    png::PixelsByColorType::RGB8(ref mut data) => {
-                        byte_swap(data);
-                        (data, PixelFormat::RGB8)
-                    }
-                    png::PixelsByColorType::RGBA8(ref mut data) => {
-                        byte_swap_and_premultiply(data);
-                        (data, PixelFormat::RGBA8)
-                    }
-                };
+    if is_jpeg(buffer) {
+        // For JPEG images, we use stb_image because piston_image does not yet support progressive
+        // JPEG.
 
-                let bytes = mem::replace(bytes, Vec::new());
-                let bytes = IpcSharedMemory::from_bytes(&bytes[..]);
-                let image = Image {
-                    width: png_image.width,
-                    height: png_image.height,
-                    format: format,
-                    bytes: bytes,
-                };
-
-                Some(image)
-            }
-            Err(_err) => None,
-        }
-    } else {
-        // For non-png images, we use stb_image
         // Can't remember why we do this. Maybe it's what cairo wants
         static FORCE_DEPTH: usize = 4;
 
@@ -111,6 +63,26 @@ pub fn load_from_memory(buffer: &[u8]) -> Option<Image> {
                 None
             }
         }
+    } else {
+        match piston_image::load_from_memory(buffer) {
+            Ok(image) => {
+                let mut rgba = match image {
+                    DynamicImage::ImageRgba8(rgba) => rgba,
+                    image => image.to_rgba()
+                };
+                byte_swap_and_premultiply(&mut *rgba);
+                Some(Image {
+                    width: rgba.width(),
+                    height: rgba.height(),
+                    format: PixelFormat::RGBA8,
+                    bytes: IpcSharedMemory::from_bytes(&*rgba),
+                })
+            }
+            Err(e) => {
+                debug!("Image decoding error: {:?}", e);
+                None
+            }
+        }
     }
 }
 
@@ -120,3 +92,7 @@ fn is_gif(buffer: &[u8]) -> bool {
         _ => false
     }
 }
+
+fn is_jpeg(buffer: &[u8]) -> bool {
+    buffer.starts_with(&[0xff, 0xd8, 0xff])
+}

components/net_traits/image_cache_task.rs

@@ -2,8 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use image::base::Image;
 use ipc_channel::ipc::{self, IpcSender};
+use msg::constellation_msg::Image;
 use std::sync::Arc;
 use url::Url;
 use util::mem::HeapSizeOf;

components/net_traits/lib.rs

@@ -18,8 +18,8 @@ extern crate log;
 extern crate euclid;
 extern crate hyper;
 extern crate ipc_channel;
+extern crate image as piston_image;
 extern crate msg;
-extern crate png;
 extern crate regex;
 extern crate serde;
 extern crate stb_image;

components/servo/Cargo.lock

@@ -15,6 +15,7 @@ dependencies = [
  "gfx_tests 0.0.1",
  "gleam 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "glutin_app 0.0.1",
+ "image 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "layers 0.1.0 (git+https://github.com/servo/rust-layers)",
  "layout 0.0.1",
  "libc 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -22,7 +23,6 @@ dependencies = [
  "net 0.0.1",
  "net_tests 0.0.1",
  "net_traits 0.0.1",
- "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "profile 0.0.1",
  "profile_traits 0.0.1",
  "script 0.0.1",
@@ -239,6 +239,11 @@ dependencies = [
  "objc 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "color_quant"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "compositing"
 version = "0.0.1"
@@ -255,6 +260,7 @@ dependencies = [
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
  "gleam 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "image 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.1.0 (git+https://github.com/pcwalton/ipc-channel)",
  "layers 0.1.0 (git+https://github.com/servo/rust-layers)",
  "layout_traits 0.0.1",
@@ -264,7 +270,6 @@ dependencies = [
  "num 0.1.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
  "plugins 0.0.1",
- "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "profile_traits 0.0.1",
  "script_traits 0.0.1",
  "style_traits 0.0.1",
@@ -494,6 +499,14 @@ dependencies = [
  "libc 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "enum_primitive"
+version = "0.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num 0.1.27 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "env_logger"
 version = "0.3.1"
@@ -660,6 +673,15 @@ dependencies = [
  "azure 0.1.0 (git+https://github.com/servo/rust-azure)",
 ]
 
+[[package]]
+name = "gif"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "color_quant 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lzw 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "gl_common"
 version = "0.0.4"
@@ -699,6 +721,11 @@ dependencies = [
  "libc 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "glob"
+version = "0.2.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "glutin"
 version = "0.3.6"
@@ -873,6 +900,19 @@ dependencies = [
  "url 0.2.37 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "image"
+version = "0.3.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 0.3.13 (registry+https://github.com/rust-lang/crates.io-index)",
+ "enum_primitive 0.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gif 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "glob 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num 0.1.27 (registry+https://github.com/rust-lang/crates.io-index)",
+ "png 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "io-surface"
 version = "0.1.0"
@@ -1049,6 +1089,11 @@ dependencies = [
  "libc 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "lzw"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "mac"
 version = "0.0.2"
@@ -1126,7 +1171,6 @@ dependencies = [
  "layers 0.1.0 (git+https://github.com/servo/rust-layers)",
  "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
  "plugins 0.0.1",
- "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1149,7 +1193,6 @@ dependencies = [
  "net_traits 0.0.1",
  "openssl 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
- "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "regex 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex_macros 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1181,11 +1224,11 @@ version = "0.0.1"
 dependencies = [
  "euclid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.6.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "image 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.1.0 (git+https://github.com/pcwalton/ipc-channel)",
  "log 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
  "plugins 0.0.1",
- "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "regex 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex_macros 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1344,22 +1387,13 @@ dependencies = [
 
 [[package]]
 name = "png"
-version = "0.1.0"
-source = "git+https://github.com/servo/rust-png#b8c2bf074719e5a39b9e4423989f5f06fa79317d"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "gcc 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bitflags 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "flate2 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "png-sys 1.6.16 (git+https://github.com/servo/rust-png)",
- "serde 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_macros 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "png-sys"
-version = "1.6.16"
-source = "git+https://github.com/servo/rust-png#b8c2bf074719e5a39b9e4423989f5f06fa79317d"
-dependencies = [
- "libz-sys 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num 0.1.27 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1962,11 +1996,11 @@ name = "webdriver_server"
 version = "0.0.1"
 dependencies = [
  "hyper 0.6.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "image 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.1.0 (git+https://github.com/pcwalton/ipc-channel)",
  "log 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
  "plugins 0.0.1",
- "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "regex 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.2.37 (registry+https://github.com/rust-lang/crates.io-index)",

components/servo/Cargo.toml

@@ -16,6 +16,9 @@ test = false
 doc = false
 bench = false
 
+[dev-dependencies]
+image = "0.3.14"
+
 [dev-dependencies.gfx_tests]
 path = "../../tests/unit/gfx"
 
@@ -36,10 +39,6 @@ name = "reftest"
 path = "../../tests/reftest.rs"
 harness = false
 
-[dependencies.png]
-git = "https://github.com/servo/rust-png"
-features = [ "serde-serialization" ]
-
 [features]
 default = ["glutin_app", "window", "webdriver"]
 window = ["glutin_app/window"]

components/webdriver_server/Cargo.toml

@@ -19,10 +19,6 @@ path = "../util"
 [dependencies.webdriver]
 git = "https://github.com/jgraham/webdriver-rust.git"
 
-[dependencies.png]
-git = "https://github.com/servo/rust-png"
-features = [ "serde-serialization" ]
-
 [dependencies.ipc-channel]
 git = "https://github.com/pcwalton/ipc-channel"
 
@@ -31,6 +27,7 @@ version = "0.2"
 features = [ "serde_serialization" ]
 
 [dependencies]
+image = "0.3.14"
 log = "0.3"
 hyper = "0.6"
 rustc-serialize = "0.3.4"

components/webdriver_server/lib.rs

@@ -11,9 +11,9 @@
 #[macro_use]
 extern crate log;
 extern crate hyper;
+extern crate image;
 extern crate ipc_channel;
 extern crate msg;
-extern crate png;
 extern crate regex;
 extern crate rustc_serialize;
 extern crate url;
@@ -22,10 +22,11 @@ extern crate uuid;
 extern crate webdriver;
 
 use hyper::method::Method::{self, Post};
+use image::{DynamicImage, ImageFormat, RgbImage};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use msg::constellation_msg::Msg as ConstellationMsg;
 use msg::constellation_msg::{ConstellationChan, FrameId, LoadData, PipelineId};
-use msg::constellation_msg::{NavigationDirection, WebDriverCommandMsg};
+use msg::constellation_msg::{NavigationDirection, PixelFormat, WebDriverCommandMsg};
 use msg::webdriver_msg::{LoadStatus, WebDriverFrameId, WebDriverJSError, WebDriverJSResult, WebDriverScriptCommand};
 use regex::Captures;
 use rustc_serialize::base64::{CharacterSet, Config, Newline, ToBase64};
@@ -615,24 +616,26 @@ impl Handler {
             sleep_ms(interval)
         }
 
-        let mut img = match img {
+        let img = match img {
             Some(img) => img,
             None => return Err(WebDriverError::new(ErrorStatus::Timeout,
                                                    "Taking screenshot timed out")),
         };
 
-        let img_vec = match png::to_vec(&mut img) {
-            Ok(x) => x,
-            Err(_) => return Err(WebDriverError::new(ErrorStatus::UnknownError,
-                                                     "Taking screenshot failed"))
-        };
+        // The compositor always sends RGB pixels.
+        assert!(img.format == PixelFormat::RGB8, "Unexpected screenshot pixel format");
+        let rgb = RgbImage::from_raw(img.width, img.height, img.bytes.to_vec()).unwrap();
+
+        let mut png_data = Vec::new();
+        DynamicImage::ImageRgb8(rgb).save(&mut png_data, ImageFormat::PNG).unwrap();
+
         let config = Config {
             char_set: CharacterSet::Standard,
             newline: Newline::LF,
             pad: true,
             line_length: None
         };
-        let encoded = img_vec.to_base64(config);
+        let encoded = png_data.to_base64(config);
         Ok(WebDriverResponse::Generic(ValueResponse::new(encoded.to_json())))
     }