Support multiple video decoders and encoders

content/common/gpu/media/gpu_video_decode_accelerator.cc

Index: content/common/gpu/media/gpu_video_decode_accelerator.cc
diff --git a/content/common/gpu/media/gpu_video_decode_accelerator.cc b/content/common/gpu/media/gpu_video_decode_accelerator.cc
index f741cb20418fbecfa99b83d54dd814f131c33892..4a3edfb2c43a77b2e12b9c3f0a7e42f0100954f6 100644
--- a/content/common/gpu/media/gpu_video_decode_accelerator.cc
+++ b/content/common/gpu/media/gpu_video_decode_accelerator.cc
@@ -32,6 +32,8 @@
 #include "content/common/gpu/media/v4l2_video_decode_accelerator.h"
 #include "content/common/gpu/media/v4l2_video_device.h"
 #elif defined(OS_CHROMEOS) && defined(ARCH_CPU_X86_FAMILY) && defined(USE_X11)
+#include "content/common/gpu/media/v4l2_video_decode_accelerator.h"
+#include "content/common/gpu/media/v4l2_video_device.h"
 #include "content/common/gpu/media/vaapi_video_decode_accelerator.h"
 #include "ui/gl/gl_context_glx.h"
 #include "ui/gl/gl_implementation.h"
@@ -236,6 +238,9 @@ void GpuVideoDecodeAccelerator::Initialize(
     SendCreateDecoderReply(init_done_msg, false);
   }
 
+  scoped_ptr<media::VideoDecodeAccelerator> decoders[2];
+  size_t n_decoders = 0;
+
 #if !defined(OS_WIN)
   // Ensure we will be able to get a GL context at all before initializing
   // non-Windows VDAs.
@@ -252,27 +257,27 @@ void GpuVideoDecodeAccelerator::Initialize(
     return;
   }
   DVLOG(0) << "Initializing DXVA HW decoder for windows.";
-  video_decode_accelerator_.reset(
+  decoders[n_decoders++].reset(
       new DXVAVideoDecodeAccelerator(make_context_current_));
 #elif defined(OS_MACOSX)
-  video_decode_accelerator_.reset(new VTVideoDecodeAccelerator(
+  decoders[n_decoders++].reset(new VTVideoDecodeAccelerator(
       static_cast<CGLContextObj>(
           stub_->decoder()->GetGLContext()->GetHandle()),
       make_context_current_));
-#elif defined(OS_CHROMEOS) && defined(ARCH_CPU_ARMEL) && defined(USE_X11)
+#elif defined(OS_CHROMEOS) && defined(USE_X11) && \
+      (defined(ARCH_CPU_X86_FAMILY) || defined(ARCH_CPU_ARMEL))
   scoped_ptr<V4L2Device> device = V4L2Device::Create(V4L2Device::kDecoder);
-  if (!device.get()) {
-    SendCreateDecoderReply(init_done_msg, false);
-    return;
+  if (device.get()) {
+    decoders[n_decoders++].reset(new V4L2VideoDecodeAccelerator(
+        gfx::GLSurfaceEGL::GetHardwareDisplay(),
+        stub_->decoder()->GetGLContext()->GetHandle(),
+        weak_factory_for_io_.GetWeakPtr(),
+        make_context_current_,
+        device.Pass(),
+        io_message_loop_));
   }
-  video_decode_accelerator_.reset(new V4L2VideoDecodeAccelerator(
-      gfx::GLSurfaceEGL::GetHardwareDisplay(),
-      stub_->decoder()->GetGLContext()->GetHandle(),
-      weak_factory_for_io_.GetWeakPtr(),
-      make_context_current_,
-      device.Pass(),
-      io_message_loop_));
-#elif defined(OS_CHROMEOS) && defined(ARCH_CPU_X86_FAMILY) && defined(USE_X11)
+#if defined(ARCH_CPU_X86_FAMILY)
+  // x86 CrOS platforms may have multiple decoders.
   if (gfx::GetGLImplementation() != gfx::kGLImplementationDesktopGL) {
     VLOG(1) << "HW video decode acceleration not available without "
                "DesktopGL (GLX).";
@@ -281,19 +286,16 @@ void GpuVideoDecodeAccelerator::Initialize(
   }
   gfx::GLContextGLX* glx_context =
       static_cast<gfx::GLContextGLX*>(stub_->decoder()->GetGLContext());
-  video_decode_accelerator_.reset(new VaapiVideoDecodeAccelerator(
+  decoders[n_decoders++].reset(new VaapiVideoDecodeAccelerator(
       glx_context->display(), make_context_current_));
+#endif
 #elif defined(USE_OZONE)
   media::MediaOzonePlatform* platform =
       media::MediaOzonePlatform::GetInstance();
-  video_decode_accelerator_.reset(platform->CreateVideoDecodeAccelerator(
+  decoders[n_decoders++].reset(platform->CreateVideoDecodeAccelerator(
       make_context_current_));
-  if (!video_decode_accelerator_) {
-    SendCreateDecoderReply(init_done_msg, false);
-    return;
-  }
 #elif defined(OS_ANDROID)
-  video_decode_accelerator_.reset(new AndroidVideoDecodeAccelerator(
+  decoders[n_decoders++].reset(new AndroidVideoDecodeAccelerator(
       stub_->decoder()->AsWeakPtr(),
       make_context_current_));
 #else
@@ -302,17 +304,30 @@ void GpuVideoDecodeAccelerator::Initialize(
   return;
 #endif
 
+  for (size_t i = 0; i < n_decoders; ++i) {
+    if (!decoders[i])
+      continue;
+    video_decode_accelerator_ = decoders[i].Pass();
+    if (InitializeDecoder(profile)) {
+      SendCreateDecoderReply(init_done_msg, true);
+      return;
+    }
+  }
+
+  SendCreateDecoderReply(init_done_msg, false);
+}
+
+bool GpuVideoDecodeAccelerator::InitializeDecoder(
+    media::VideoCodecProfile profile) {
+  if (!video_decode_accelerator_.get() ||
+      !video_decode_accelerator_->Initialize(profile, this))
+    return false;
+
   if (video_decode_accelerator_->CanDecodeOnIOThread()) {
     filter_ = new MessageFilter(this, host_route_id_);
     stub_->channel()->AddFilter(filter_.get());
   }
-
-  if (!video_decode_accelerator_->Initialize(profile, this)) {
-    SendCreateDecoderReply(init_done_msg, false);
-    return;
-  }
-
-  SendCreateDecoderReply(init_done_msg, true);
+  return true;
 }
 
 // Runs on IO thread if video_decode_accelerator_->CanDecodeOnIOThread() is