16 bpp video stream capture, render and createImageBitmap(video) using (CPU) shared memory buffers

media/capture/video/fake_video_capture_device_factory.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/capture/video/fake_video_capture_device_factory.h"
 
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_tokenizer.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "build/build_config.h"
 #include "media/base/media_switches.h"
 
+namespace {
+
+media::VideoPixelFormat get_pixelformat(const std::string& device_id) {
+  if (device_id == "/dev/video1")
+    return media::PIXEL_FORMAT_Y16;
+  return media::PIXEL_FORMAT_I420;
+}
+
+}
+
 namespace media {
 
 // Cap the frame rate command line input to reasonable values.
 static const float kFakeCaptureMinFrameRate = 5.0f;
 static const float kFakeCaptureMaxFrameRate = 60.0f;
 // Default rate if none is specified as part of the command line.
 static const float kFakeCaptureDefaultFrameRate = 20.0f;
 
+// Factory has two devices by default; I420 and Y16. See also get_pixelformat().
 FakeVideoCaptureDeviceFactory::FakeVideoCaptureDeviceFactory()
-    : number_of_devices_(1),
+    : number_of_devices_(2),
       fake_vcd_ownership_(FakeVideoCaptureDevice::BufferOwnership::OWN_BUFFERS),
       frame_rate_(kFakeCaptureDefaultFrameRate) {}
 
 std::unique_ptr<VideoCaptureDevice> FakeVideoCaptureDeviceFactory::CreateDevice(
     const VideoCaptureDeviceDescriptor& device_descriptor) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   parse_command_line();
 
   for (int n = 0; n < number_of_devices_; ++n) {
     std::string possible_id = base::StringPrintf("/dev/video%d", n);
     if (device_descriptor.device_id.compare(possible_id) == 0) {
-      return std::unique_ptr<VideoCaptureDevice>(
-          new FakeVideoCaptureDevice(fake_vcd_ownership_, frame_rate_));
+      return std::unique_ptr<VideoCaptureDevice>(new FakeVideoCaptureDevice(
+          fake_vcd_ownership_, frame_rate_, get_pixelformat(possible_id)));
     }
   }
   return std::unique_ptr<VideoCaptureDevice>();
 }
 
 void FakeVideoCaptureDeviceFactory::GetDeviceDescriptors(
     VideoCaptureDeviceDescriptors* device_descriptors) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(device_descriptors->empty());
   for (int n = 0; n < number_of_devices_; ++n) {
     device_descriptors->emplace_back(base::StringPrintf("fake_device_%d", n),
                                      base::StringPrintf("/dev/video%d", n),
 #if defined(OS_LINUX)
                                      VideoCaptureApi::LINUX_V4L2_SINGLE_PLANE
 #elif defined(OS_MACOSX)
                                      VideoCaptureApi::MACOSX_AVFOUNDATION
 #elif defined(OS_WIN)
                                      VideoCaptureApi::WIN_DIRECT_SHOW
 #elif defined(OS_ANDROID)
                                      VideoCaptureApi::ANDROID_API2_LEGACY
 #endif
                                      );
   }
 }
 
 void FakeVideoCaptureDeviceFactory::GetSupportedFormats(
     const VideoCaptureDeviceDescriptor& device_descriptor,
     VideoCaptureFormats* supported_formats) {
   DCHECK(thread_checker_.CalledOnValidThread());
-  const gfx::Size supported_sizes[] = {gfx::Size(320, 240),
+  const gfx::Size supported_sizes[] = {gfx::Size(96, 96), // To test cubemap.
+                                       gfx::Size(320, 240),
                                        gfx::Size(640, 480),
                                        gfx::Size(1280, 720),
                                        gfx::Size(1920, 1080)};
   supported_formats->clear();
   for (const auto& size : supported_sizes) {
-    supported_formats->push_back(
-        VideoCaptureFormat(size, frame_rate_, media::PIXEL_FORMAT_I420));
+    supported_formats->push_back(VideoCaptureFormat(
+        size, frame_rate_, get_pixelformat(device_descriptor.device_id)));
   }
 }
 
 // Optional comma delimited parameters to the command line can specify buffer
 // ownership, buffer planarity, and the fake video device FPS.
 // Examples: "ownership=client, planarity=triplanar, fps=60" "fps=30"
 void FakeVideoCaptureDeviceFactory::parse_command_line() {
   const std::string option =
       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
           switches::kUseFakeDeviceForMediaStream);
@@ skipping 20 matching lines @@
       if (base::StringToDouble(param.back(), &fps)) {
         frame_rate_ =
             std::max(kFakeCaptureMinFrameRate, static_cast<float>(fps));
         frame_rate_ = std::min(kFakeCaptureMaxFrameRate, frame_rate_);
       }
     }
   }
 }
 
 }  // namespace media