Add MJPEG support to FakeVideoCaptureDevice

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 {
 namespace {
 
 static const size_t kDepthDeviceIndex = 1;
-static const char kDepthDeviceId[] = "/dev/video1";
-
-media::VideoPixelFormat GetPixelFormatFromDeviceId(
-    const std::string& device_id) {
-  return (device_id == kDepthDeviceId) ? media::PIXEL_FORMAT_Y16
-                                       : 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;
 
+FakeVideoCaptureDeviceMaker::PixelFormat GetPixelFormatFromDeviceId(
+    const std::string& device_id) {
+  if (device_id == "/dev/video1")
+    return FakeVideoCaptureDeviceMaker::PixelFormat::Y16;
+  if (device_id == "/dev/video2")
+    return FakeVideoCaptureDeviceMaker::PixelFormat::MJPEG;
+  return FakeVideoCaptureDeviceMaker::PixelFormat::I420;
+}
+
+}  // anonymous namespace
+
 FakeVideoCaptureDeviceFactory::FakeVideoCaptureDeviceFactory()
     : number_of_devices_(1),
       delivery_mode_(FakeVideoCaptureDeviceMaker::DeliveryMode::
                          USE_DEVICE_INTERNAL_BUFFERS),
       frame_rate_(kFakeCaptureDefaultFrameRate) {}
 
 std::unique_ptr<VideoCaptureDevice> FakeVideoCaptureDeviceFactory::CreateDevice(
     const VideoCaptureDeviceDescriptor& device_descriptor) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   ParseCommandLine();
 
   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) {
+      FakeVideoCaptureDeviceMaker::PixelFormat pixel_format =
+          GetPixelFormatFromDeviceId(possible_id);
+      FakeVideoCaptureDeviceMaker::DeliveryMode delivery_mode = delivery_mode_;
+      if (delivery_mode ==
+              FakeVideoCaptureDeviceMaker::DeliveryMode::
+                  USE_CLIENT_PROVIDED_BUFFERS &&
+          pixel_format == FakeVideoCaptureDeviceMaker::PixelFormat::MJPEG) {
+        // Incompatible options. Fall back to using internal buffers.
+        delivery_mode = FakeVideoCaptureDeviceMaker::DeliveryMode::
+            USE_DEVICE_INTERNAL_BUFFERS;
+      }
       return FakeVideoCaptureDeviceMaker::MakeInstance(
-          GetPixelFormatFromDeviceId(possible_id), delivery_mode_, frame_rate_);
+          pixel_format, delivery_mode, frame_rate_);
     }
   }
   return std::unique_ptr<VideoCaptureDevice>();
 }
 
 void FakeVideoCaptureDeviceFactory::GetDeviceDescriptors(
     VideoCaptureDeviceDescriptors* device_descriptors) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(device_descriptors->empty());
 
@@ skipping 27 matching lines @@
   depth_device.camera_calibration->depth_far = 65.535;
 }
 
 void FakeVideoCaptureDeviceFactory::GetSupportedFormats(
     const VideoCaptureDeviceDescriptor& device_descriptor,
     VideoCaptureFormats* supported_formats) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   ParseCommandLine();
 
-  const VideoPixelFormat pixel_format =
-      GetPixelFormatFromDeviceId(device_descriptor.device_id);
+  const VideoPixelFormat pixel_format = static_cast<VideoPixelFormat>(
+      GetPixelFormatFromDeviceId(device_descriptor.device_id));
   const VideoPixelStorage pixel_storage = PIXEL_STORAGE_CPU;
   std::vector<gfx::Size> supported_sizes;
   FakeVideoCaptureDeviceMaker::GetSupportedSizes(&supported_sizes);
   for (const auto& supported_size : supported_sizes) {
     supported_formats->emplace_back(supported_size, frame_rate_, pixel_format,
                                     pixel_storage);
   }
 }
 
 // Optional comma delimited parameters to the command line can specify buffer
@@ skipping 38 matching lines @@
       if (base::StringToUint(param.back(), &count)) {
         number_of_devices_ = std::min(
             kFakeCaptureMaxDeviceCount,
             std::max(kFakeCaptureMinDeviceCount, static_cast<int>(count)));
       }
     }
   }
 }
 
 }  // namespace media