Rotate frames according to camera orientation

media/capture/video/linux/camera_facing_chromeos.h

-// 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.
-
-#ifndef MEDIA_CAPTURE_VIDEO_LINUX_CAMERA_FACING_CHROMEOS_H_
-#define MEDIA_CAPTURE_VIDEO_LINUX_CAMERA_FACING_CHROMEOS_H_
-
-#include <stddef.h>
-
-#include <string>
-#include <unordered_map>
-
-#include <base/strings/string_piece.h>
-#include "media/base/video_facing.h"
-#include "media/capture/capture_export.h"
-
-namespace media {
-
-// CameraFacingChromeOS reads the file /etc/camera/camera_characteristics.conf
-// and populates |camera_id_to_facing_|, |usb_id_to_camera_id_| and
-// |model_id_to_camera_id_|.
-//
-// Each line in the config file can be:
-// 1. Empty line
-// 2. Line starts with '#': comments
-// 3. Line follows the format:
-// camera[camera_id].[root_level_attribute]=[value] OR
-// camera[camera_id].module[module_id].[module_level_attribute]=[value]
-//
-// There are several assumptions of the config file:
-//  1. One camera ID has exactly one lens_facing attribute, at root level.
-//  2. usb_path is specified at module level. usb_path may not present at all,
-//  but if it presents, the same usb_path does not appear accross different
-//  camera IDs.
-//  3. usb_vid_pid is specified at module level. If usb_path does not present,
-//  each module needs to have one unique usb_vid_pid.
-//
-// Example of the config file:
-//  camera0.lens_facing=0
-//  camera0.sensor_orientation=0
-//  camera0.module0.usb_vid_pid=0123:4567
-//  camera0.module0.horizontal_view_angle=68.4
-//  camera0.module0.lens_info_available_focal_lengths=1.64
-//  camera0.module0.lens_info_minimum_focus_distance=0.22
-//  camera0.module0.lens_info_optimal_focus_distance=0.5
-//  camera0.module0.vertical_view_angle=41.6
-//  camera0.module1.usb_vid_pid=89ab:cdef
-//  camera0.module1.lens_info_available_focal_lengths=1.69,2
-//  camera1.lens_facing=1
-//  camera1.sensor_orientation=180
-class CAPTURE_EXPORT CameraFacingChromeOS {
- public:
-  CameraFacingChromeOS();
-  CAPTURE_EXPORT CameraFacingChromeOS(const std::string& config_file_path);
-  CAPTURE_EXPORT ~CameraFacingChromeOS();
-
-  // Get camera facing by specifying USB vid and pid and device path. |model_id|
-  // should be formatted as "vid:pid". |device_id| is something like
-  // "/dev/video2". It first tries to match usb path, obtained from |device_id|.
-  // If fails, |model_id| is then used.
-  CAPTURE_EXPORT VideoFacingMode
-  GetCameraFacing(const std::string& device_id,
-                  const std::string& model_id) const;
-
-  static const VideoFacingMode kLensFacingDefault =
-      VideoFacingMode::MEDIA_VIDEO_FACING_NONE;
-
- private:
-  std::string GetUsbId(const std::string& device_id) const;
-  // Read file content and populate |camera_id_to_facing_|,
-  // |usb_id_to_camera_id_| and |model_id_to_camera_id_|.
-  void InitializeDeviceInfo(const std::string& config_file_path);
-
-  std::unordered_map<int, VideoFacingMode> camera_id_to_facing_;
-  std::unordered_map<std::string, int> usb_id_to_camera_id_;
-  std::unordered_map<std::string, int> model_id_to_camera_id_;
-};
-
-}  // namespace media
-
-#endif  // MEDIA_CAPTURE_VIDEO_LINUX_CAMERA_FACING_CHROMEOS_H_