--- a/content/media/Makefile.in
+++ b/content/media/Makefile.in
@@ -13,16 +13,20 @@ LIBRARY_NAME = gkconmedia_s
 MSVC_ENABLE_PGO := 1
 LIBXUL_LIBRARY = 1
 FAIL_ON_WARNINGS := 1
 
 include $(topsrcdir)/config/config.mk
 include $(topsrcdir)/config/rules.mk
 include $(topsrcdir)/ipc/chromium/chromium-config.mk
 
-INCLUDES  += \
+LOCAL_INCLUDES  += \
   -I$(topsrcdir)/content/base/src \
   -I$(topsrcdir)/layout/generic \
   -I$(topsrcdir)/layout/xul/base/src \
   $(NULL)
 
+ifdef MOZ_DIRECTSHOW
+LOCAL_INCLUDES += -I$(topsrcdir)/media/webrtc/trunk/webrtc/modules/video_capture/windows/
+endif
+
 CFLAGS   += $(GSTREAMER_CFLAGS)
 CXXFLAGS += $(GSTREAMER_CFLAGS)

new file mode 100644
--- /dev/null
+++ b/content/media/directshow/Makefile.in
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# 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/.
+
+DEPTH		= @DEPTH@
+topsrcdir	= @top_srcdir@
+srcdir		= @srcdir@
+VPATH		= @srcdir@
+
+include $(DEPTH)/config/autoconf.mk
+
+FAIL_ON_WARNINGS := 1
+
+LIBRARY_NAME	= gkcondirectshow_s
+LIBXUL_LIBRARY 	= 1
+
+LOCAL_INCLUDES += -I$(topsrcdir)/media/webrtc/trunk/webrtc/modules/video_capture/windows/
+
+ifeq ($(OS_ARCH),WINNT)
+OS_CXXFLAGS += -DNOMINMAX
+endif
+
+include $(topsrcdir)/config/rules.mk

new file mode 100644
--- /dev/null
+++ b/content/media/directshow/moz.build
@@ -0,0 +1,35 @@
+# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# 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/.
+
+MODULE = 'content'
+
+EXPORTS += [
+    'AudioSinkFilter.h',
+    'AudioSinkInputPin.h',
+    'DirectShowDecoder.h',
+    'DirectShowReader.h',
+    'DirectShowUtils.h',
+]
+
+CPP_SOURCES += [
+    'AudioSinkFilter.cpp',
+    'AudioSinkInputPin.cpp',
+    'DirectShowDecoder.cpp',
+    'DirectShowReader.cpp',
+    'DirectShowUtils.cpp',
+    'SampleSink.cpp',
+    'SourceFilter.cpp',
+]
+
+# If WebRTC isn't being built, we need to compile the DirectShow base classes so that
+# they're available at link time.
+if not CONFIG['MOZ_WEBRTC_IN_LIBXUL']:
+    CPP_SOURCES += [
+        TOPSRCDIR + '/media/webrtc/trunk/webrtc/modules/video_capture/windows/BaseFilter.cpp',
+        TOPSRCDIR + '/media/webrtc/trunk/webrtc/modules/video_capture/windows/BaseInputPin.cpp',
+        TOPSRCDIR + '/media/webrtc/trunk/webrtc/modules/video_capture/windows/BasePin.cpp',
+        TOPSRCDIR + '/media/webrtc/trunk/webrtc/modules/video_capture/windows/MediaType.cpp',
+    ]

--- a/content/media/moz.build
+++ b/content/media/moz.build
@@ -23,16 +23,19 @@ if CONFIG['MOZ_WEBM']:
     PARALLEL_DIRS += ['webm']
 
 if CONFIG['MOZ_GSTREAMER']:
     PARALLEL_DIRS += ['gstreamer']
 
 if CONFIG['MOZ_DASH']:
     PARALLEL_DIRS += ['dash']
 
+if CONFIG['MOZ_DIRECTSHOW']:
+    PARALLEL_DIRS += ['directshow']
+
 if CONFIG['MOZ_MEDIA_PLUGINS']:
     PARALLEL_DIRS += ['plugins']
 
 if CONFIG['MOZ_WMF']:
     PARALLEL_DIRS += ['wmf']
 
 PARALLEL_DIRS += ['webrtc']
 

--- a/layout/build/Makefile.in
+++ b/layout/build/Makefile.in
@@ -167,16 +167,22 @@ SHARED_LIBRARY_LIBS 	+= \
 endif
 
 ifdef MOZ_WMF
 SHARED_LIBRARY_LIBS 	+= \
 	$(DEPTH)/content/media/wmf/$(LIB_PREFIX)gkconwmf_s.$(LIB_SUFFIX) \
 	$(NULL)
 endif
 
+ifdef MOZ_DIRECTSHOW
+SHARED_LIBRARY_LIBS 	+= \
+	$(DEPTH)/content/media/directshow/$(LIB_PREFIX)gkcondirectshow_s.$(LIB_SUFFIX) \
+	$(NULL)
+endif
+
 ifdef MOZ_WAVE
 SHARED_LIBRARY_LIBS 	+= \
 	$(DEPTH)/content/media/wave/$(LIB_PREFIX)gkconwave_s.$(LIB_SUFFIX) \
 	$(NULL)
 endif
 
 ifdef MOZ_GSTREAMER
 SHARED_LIBRARY_LIBS 	+= \

--- a/toolkit/library/Makefile.in
+++ b/toolkit/library/Makefile.in
@@ -463,16 +463,20 @@ OS_LIBS += \
   -lgui \
   $(NULL)
 endif
 
 ifdef MOZ_WMF
 OS_LIBS += $(call EXPAND_LIBNAME,mfuuid wmcodecdspuuid strmiids)
 endif
 
+ifdef MOZ_DIRECTSHOW
+OS_LIBS += $(call EXPAND_LIBNAME,dmoguids wmcodecdspuuid strmiids msdmo)
+endif
+
 EXTRA_DEPS += \
   $(topsrcdir)/intl/unicharutil/util/objs.mk \
   $(topsrcdir)/rdf/util/src/objs.mk \
   $(NULL)
 
 GARBAGE += \
   $(INTL_UNICHARUTIL_UTIL_LCPPSRCS) \
   $(RDF_UTIL_SRC_LCPPSRCS) \