FakeVideoCaptureDevice: Y16 testing support.

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 {
+
+// Factory has one device by default; I420. If there are more, the second device
+// is of Y16 format while the rest are I420.
+media::VideoPixelFormat GetPixelFormat(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;
+// Cap the device count command line input to reasonable values.
+static const int kFakeCaptureMinDeviceCount = 1;
+static const int kFakeCaptureMaxDeviceCount = 10;
 
 FakeVideoCaptureDeviceFactory::FakeVideoCaptureDeviceFactory()
     : number_of_devices_(1),
       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_, GetPixelFormat(possible_id)));
     }
   }
   return std::unique_ptr<VideoCaptureDevice>();
 }
 
 void FakeVideoCaptureDeviceFactory::GetDeviceDescriptors(
     VideoCaptureDeviceDescriptors* device_descriptors) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(device_descriptors->empty());
+
+  parse_command_line();
+
   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),
-                                       gfx::Size(640, 480),
-                                       gfx::Size(1280, 720),
-                                       gfx::Size(1920, 1080)};
+  const gfx::Size supported_sizes[] = {
+      gfx::Size(96, 96), 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_, GetPixelFormat(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"
+// ownership, device count, and the fake video devices FPS.
+// Examples: "ownership=client, device-count=2, fps=60" "fps=30"
 void FakeVideoCaptureDeviceFactory::parse_command_line() {
+  if (command_line_parsed_)
+    return;
+  command_line_parsed_ = true;

[mcasas, 2016/10/26 02:03:15]

nit; consider doing this flag management directly in l. 64.

Also, s/parse_command_line/ParseCommandLine/ 
(I know it's not your fault but since you're in the 
area anyhow... )

[aleksandar.stojiljkovic, 2016/10/26 14:46:01]

Done, both good points.

   const std::string option =
       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
           switches::kUseFakeDeviceForMediaStream);
   base::StringTokenizer option_tokenizer(option, ", ");
   option_tokenizer.set_quote_chars("\"");
 
   while (option_tokenizer.GetNext()) {
     std::vector<std::string> param =
         base::SplitString(option_tokenizer.token(), "=", base::TRIM_WHITESPACE,
                           base::SPLIT_WANT_NONEMPTY);
 
     if (param.size() != 2u) {
       LOG(WARNING) << "Forget a value '" << option << "'? Use name=value for "
                    << switches::kUseFakeDeviceForMediaStream << ".";
       return;
     }
 
     if (base::EqualsCaseInsensitiveASCII(param.front(), "ownership") &&
         base::EqualsCaseInsensitiveASCII(param.back(), "client")) {
       fake_vcd_ownership_ =
           FakeVideoCaptureDevice::BufferOwnership::CLIENT_BUFFERS;
     } else if (base::EqualsCaseInsensitiveASCII(param.front(), "fps")) {
       double fps = 0;
       if (base::StringToDouble(param.back(), &fps)) {
         frame_rate_ =
             std::max(kFakeCaptureMinFrameRate, static_cast<float>(fps));
         frame_rate_ = std::min(kFakeCaptureMaxFrameRate, frame_rate_);
       }
+    } else if (base::EqualsCaseInsensitiveASCII(param.front(),
+                                                "device-count")) {
+      unsigned int count = 0;
+      if (base::StringToUint(param.back(), &count)) {
+        number_of_devices_ = std::min(
+            kFakeCaptureMaxDeviceCount,
+            std::max(kFakeCaptureMinDeviceCount, static_cast<int>(count)));
+      }
     }
   }
 }
 
 }  // namespace media