feat: add support for DesktopCapturerSource.appIcon

Useful to get the icon of the application owning the source.
Only available for sources of type window, i.e. not for screen.

https://github.com/electron/electron/issues/14845

atom/browser/api/atom_api_desktop_capturer.cc

@@ -14,6 +14,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_restrictions.h"
 #include "chrome/browser/media/webrtc/desktop_media_list.h"
+#include "chrome/browser/media/webrtc/window_icon_util.h"
 #include "content/public/browser/desktop_capture.h"
 #include "native_mate/dictionary.h"
 #include "third_party/webrtc/modules/desktop_capture/desktop_capture_options.h"
@@ -42,6 +43,12 @@ struct Converter<atom::api::DesktopCapturer::Source> {
              atom::api::NativeImage::Create(
                  isolate, gfx::Image(source.media_list_source.thumbnail)));
     dict.Set("display_id", source.display_id);
+    if (source.fetch_icon) {
+      dict.Set(
+          "appIcon",
+          atom::api::NativeImage::Create(
+              isolate, gfx::Image(GetWindowIcon(source.media_list_source.id))));
+    }
     return ConvertToV8(isolate, dict);
   }
 };
@@ -60,7 +67,9 @@ DesktopCapturer::~DesktopCapturer() {}
 
 void DesktopCapturer::StartHandling(bool capture_window,
                                     bool capture_screen,
-                                    const gfx::Size& thumbnail_size) {
+                                    const gfx::Size& thumbnail_size,
+                                    bool fetch_window_icons) {
+  fetch_window_icons_ = fetch_window_icons;
 #if defined(OS_WIN)
   if (content::desktop_capture::CreateDesktopCaptureOptions()
           .allow_directx_capturer()) {
@@ -134,8 +143,8 @@ void DesktopCapturer::UpdateSourcesList(DesktopMediaList* list) {
     capture_window_ = false;
     const auto& media_list_sources = list->GetSources();
     for (const auto& media_list_source : media_list_sources) {
-      window_sources.emplace_back(
+      window_sources.emplace_back(DesktopCapturer::Source{
-          DesktopCapturer::Source{media_list_source, std::string()});
+          media_list_source, std::string(), fetch_window_icons_});
     }
     std::move(window_sources.begin(), window_sources.end(),
               std::back_inserter(captured_sources_));
@@ -187,7 +196,7 @@ void DesktopCapturer::UpdateSourcesList(DesktopMediaList* list) {
   }
 
   if (!capture_window_ && !capture_screen_)
-    Emit("finished", captured_sources_);
+    Emit("finished", captured_sources_, fetch_window_icons_);
 }
 
 // static

atom/browser/api/atom_api_desktop_capturer.h

@@ -25,6 +25,9 @@ class DesktopCapturer : public mate::EventEmitter<DesktopCapturer>,
     DesktopMediaList::Source media_list_source;
     // Will be an empty string if not available.
     std::string display_id;
+
+    // Whether or not this source should provide an icon.
+    bool fetch_icon = false;
   };
 
   static mate::Handle<DesktopCapturer> Create(v8::Isolate* isolate);
@@ -34,7 +37,8 @@ class DesktopCapturer : public mate::EventEmitter<DesktopCapturer>,
 
   void StartHandling(bool capture_window,
                      bool capture_screen,
-                     const gfx::Size& thumbnail_size);
+                     const gfx::Size& thumbnail_size,
+                     bool fetch_window_icons);
 
  protected:
   explicit DesktopCapturer(v8::Isolate* isolate);
@@ -59,6 +63,7 @@ class DesktopCapturer : public mate::EventEmitter<DesktopCapturer>,
   std::vector<DesktopCapturer::Source> captured_sources_;
   bool capture_window_ = false;
   bool capture_screen_ = false;
+  bool fetch_window_icons_ = false;
 #if defined(OS_WIN)
   bool using_directx_capturer_ = false;
 #endif  // defined(OS_WIN)

chromium_src/BUILD.gn

@@ -72,6 +72,7 @@ static_library("chrome") {
       "//chrome/browser/media/webrtc/desktop_media_list_observer.h",
       "//chrome/browser/media/webrtc/native_desktop_media_list.cc",
       "//chrome/browser/media/webrtc/native_desktop_media_list.h",
+      "//chrome/browser/media/webrtc/window_icon_util.h",
     ]
     deps += [ "//ui/snapshot" ]
   }
@@ -93,6 +94,7 @@ static_library("chrome") {
 
     if (is_mac) {
       sources += [
+        "//chrome/browser/media/webrtc/window_icon_util_mac.mm",
         "//chrome/browser/ui/cocoa/color_chooser_mac.h",
         "//chrome/browser/ui/cocoa/color_chooser_mac.mm",
       ]
@@ -100,6 +102,7 @@ static_library("chrome") {
 
     if (is_win) {
       sources += [
+        "//chrome/browser/media/webrtc/window_icon_util_win.cc",
         "//chrome/browser/ui/views/color_chooser_dialog.cc",
         "//chrome/browser/ui/views/color_chooser_dialog.h",
         "//chrome/browser/ui/views/color_chooser_win.cc",
@@ -126,7 +129,10 @@ static_library("chrome") {
     ]
 
     if (is_linux) {
-      sources += [ "//chrome/browser/speech/tts_linux.cc" ]
+      sources += [
+        "//chrome/browser/media/webrtc/window_icon_util_x11.cc",
+        "//chrome/browser/speech/tts_linux.cc",
+      ]
       deps += [ "//third_party/speech-dispatcher" ]
     }
   }

docs/api/desktop-capturer.md

@@ -84,6 +84,9 @@ The `desktopCapturer` module has the following methods:
     to be captured, available types are `screen` and `window`.
   * `thumbnailSize` [Size](structures/size.md) (optional) - The size that the media source thumbnail
     should be scaled to. Default is `150` x `150`.
+  * `fetchWindowIcons` Boolean (optional) - Set to true to enable fetching window icons. The default
+    value is false. When false the appIcon property of the sources return null. Same if a source has
+    the type screen.
 * `callback` Function
   * `error` Error
   * `sources` [DesktopCapturerSource[]](structures/desktop-capturer-source.md)

docs/api/structures/desktop-capturer-source.md

@@ -17,3 +17,7 @@
   On some platforms, this is equivalent to the `XX` portion of the `id` field
   above and on others it will differ. It will be an empty string if not
   available.
+* `appIcon` [NativeImage](../native-image.md) - An icon image of the
+  application that owns the window or null if the source has a type screen.
+  The size of the icon is not known in advance and depends on what the
+  the application provides.

lib/browser/desktop-capturer.js

@@ -11,19 +11,20 @@ let requestsQueue = []
 const electronSources = 'ELECTRON_BROWSER_DESKTOP_CAPTURER_GET_SOURCES'
 const capturerResult = (id) => `ELECTRON_RENDERER_DESKTOP_CAPTURER_RESULT_${id}`
 
-ipcMain.on(electronSources, (event, captureWindow, captureScreen, thumbnailSize, id) => {
+ipcMain.on(electronSources, (event, captureWindow, captureScreen, thumbnailSize, fetchWindowIcons, id) => {
   const request = {
     id,
     options: {
       captureWindow,
       captureScreen,
-      thumbnailSize
+      thumbnailSize,
+      fetchWindowIcons
     },
     webContents: event.sender
   }
   requestsQueue.push(request)
   if (requestsQueue.length === 1) {
-    desktopCapturer.startHandling(captureWindow, captureScreen, thumbnailSize)
+    desktopCapturer.startHandling(captureWindow, captureScreen, thumbnailSize, fetchWindowIcons)
   }
 
   // If the WebContents is destroyed before receiving result, just remove the
@@ -33,7 +34,7 @@ ipcMain.on(electronSources, (event, captureWindow, captureScreen, thumbnailSize,
   })
 })
 
-desktopCapturer.emit = (event, name, sources) => {
+desktopCapturer.emit = (event, name, sources, fetchWindowIcons) => {
   // Receiving sources result from main process, now send them back to renderer.
   const handledRequest = requestsQueue.shift()
   const handledWebContents = handledRequest.webContents
@@ -44,7 +45,8 @@ desktopCapturer.emit = (event, name, sources) => {
       id: source.id,
       name: source.name,
       thumbnail: source.thumbnail.toDataURL(),
-      display_id: source.display_id
+      display_id: source.display_id,
+      appIcon: (fetchWindowIcons && source.appIcon) ? source.appIcon.toDataURL() : null
     }
   })
 
@@ -67,7 +69,7 @@ desktopCapturer.emit = (event, name, sources) => {
 
   // If the requestsQueue is not empty, start a new request handling.
   if (requestsQueue.length > 0) {
-    const { captureWindow, captureScreen, thumbnailSize } = requestsQueue[0].options
+    const { captureWindow, captureScreen, thumbnailSize, fetchWindowIcons } = requestsQueue[0].options
-    return desktopCapturer.startHandling(captureWindow, captureScreen, thumbnailSize)
+    return desktopCapturer.startHandling(captureWindow, captureScreen, thumbnailSize, fetchWindowIcons)
   }
 }

lib/renderer/api/desktop-capturer.js

@@ -28,9 +28,12 @@ exports.getSources = function (options, callback) {
       height: 150
     }
   }
+  if (options.fetchWindowIcons == null) {
+    options.fetchWindowIcons = false
+  }
 
   const id = incrementId()
-  ipcRenderer.send('ELECTRON_BROWSER_DESKTOP_CAPTURER_GET_SOURCES', captureWindow, captureScreen, options.thumbnailSize, id)
+  ipcRenderer.send('ELECTRON_BROWSER_DESKTOP_CAPTURER_GET_SOURCES', captureWindow, captureScreen, options.thumbnailSize, options.fetchWindowIcons, id)
   return ipcRenderer.once(`ELECTRON_RENDERER_DESKTOP_CAPTURER_RESULT_${id}`, (event, sources) => {
     callback(null, (() => {
       const results = []
@@ -39,7 +42,8 @@ exports.getSources = function (options, callback) {
           id: source.id,
           name: source.name,
           thumbnail: nativeImage.createFromDataURL(source.thumbnail),
-          display_id: source.display_id
+          display_id: source.display_id,
+          appIcon: source.appIcon ? nativeImage.createFromDataURL(source.appIcon) : null
         })
       })
       return results