services/video_capture/public/interfaces/video_capture_device_factory.mojom

// Copyright 2016 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.

module video_capture.mojom;

import "services/video_capture/public/interfaces/video_capture_device_proxy.mojom";
import "services/video_capture/public/interfaces/video_capture_format.mojom";

enum VideoCaptureApi {
  LINUX_V4L2_SINGLE_PLANE,
  WIN_MEDIA_FOUNDATION,
  WIN_DIRECT_SHOW,
  MACOSX_AVFOUNDATION,
  MACOSX_DECKLINK,
  ANDROID_API1,
  ANDROID_API2_LEGACY,
  ANDROID_API2_FULL,
  ANDROID_API2_LIMITED,
  ANDROID_TANGO,
  UNKNOWN
};

enum VideoCaptureTransportType {
  // For MACOSX_AVFOUNDATION Api, identifies devices that are built-in or USB.
  MACOSX_USB_OR_BUILT_IN,
  OTHER_TRANSPORT
};

enum DeviceAccessResultCode {
  NOT_INITIALIZED,
  SUCCESS,
  ERROR_DEVICE_NOT_FOUND
};

struct VideoCaptureDeviceDescriptor {
  string display_name;
  string device_id;
  string model_id;
  VideoCaptureApi capture_api;
  VideoCaptureTransportType transport_type;
};

// Entry point for accessing video capture devices available on the machine.
// Typical operation is to first call EnumerateDeviceDescriptors() to obtain
// information about available devices. The obtained descriptors can then be
// used to either obtain the supported formats of a device using
// GetSupportedFormats(), or to create an instance of VideoCaptureDevice for
// the device using CreateDevice().
// TODO(chfremer): Consider using a simple string identifier instead of a
// VideoCaptureDeviceDescriptor.
// https://crbug.com/637439
interface VideoCaptureDeviceFactory {
  EnumerateDeviceDescriptors()
      => (array<VideoCaptureDeviceDescriptor> descriptors);

  GetSupportedFormats(VideoCaptureDeviceDescriptor device_descriptor)
      => (array<VideoCaptureFormat> supported_formats);

  // Provides exclusive access to the device identified by |device_descriptor|.
  // The access is valid until either the message pipe associated with
  // |proxy_request| is closed by the client, or a subsequent call to
  // CreateDeviceProxy() is made.
  CreateDeviceProxy(VideoCaptureDeviceDescriptor device_descriptor,
                    VideoCaptureDeviceProxy& proxy_request)
      => (DeviceAccessResultCode result_code);
};