blob: d037c95de82a726607996c22831c99cae355bb3e
| 1 | /* |
| 2 | * Copyright (C) 2011 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef HW_EMULATOR_CAMERA_PREVIEW_WINDOW_H |
| 18 | #define HW_EMULATOR_CAMERA_PREVIEW_WINDOW_H |
| 19 | |
| 20 | /* |
| 21 | * Contains declaration of a class PreviewWindow that encapsulates functionality |
| 22 | * of a preview window set via set_preview_window camera HAL API. |
| 23 | */ |
| 24 | |
| 25 | namespace android { |
| 26 | |
| 27 | class EmulatedCameraDevice; |
| 28 | |
| 29 | /* Encapsulates functionality of a preview window set via set_preview_window |
| 30 | * camera HAL API. |
| 31 | * |
| 32 | * Objects of this class are contained in EmulatedCamera objects, and handle |
| 33 | * relevant camera API callbacks. |
| 34 | */ |
| 35 | class PreviewWindow { |
| 36 | public: |
| 37 | /* Constructs PreviewWindow instance. */ |
| 38 | PreviewWindow(); |
| 39 | |
| 40 | /* Destructs PreviewWindow instance. */ |
| 41 | ~PreviewWindow(); |
| 42 | |
| 43 | /*************************************************************************** |
| 44 | * Camera API |
| 45 | **************************************************************************/ |
| 46 | |
| 47 | public: |
| 48 | /* Actual handler for camera_device_ops_t::set_preview_window callback. |
| 49 | * This method is called by the containing emulated camera object when it is |
| 50 | * handing the camera_device_ops_t::set_preview_window callback. |
| 51 | * Param: |
| 52 | * window - Preview window to set. This parameter might be NULL, which |
| 53 | * indicates preview window reset. |
| 54 | * preview_fps - Preview's frame frequency. This parameter determins when |
| 55 | * a frame received via onNextFrameAvailable call will be pushed to |
| 56 | * the preview window. If 'window' parameter passed to this method is |
| 57 | * NULL, this parameter is ignored. |
| 58 | * Return: |
| 59 | * NO_ERROR on success, or an appropriate error status. |
| 60 | */ |
| 61 | status_t setPreviewWindow(struct preview_stream_ops* window, |
| 62 | int preview_fps); |
| 63 | |
| 64 | /* Starts the preview. |
| 65 | * This method is called by the containing emulated camera object when it is |
| 66 | * handing the camera_device_ops_t::start_preview callback. |
| 67 | */ |
| 68 | status_t startPreview(); |
| 69 | |
| 70 | /* Stops the preview. |
| 71 | * This method is called by the containing emulated camera object when it is |
| 72 | * handing the camera_device_ops_t::start_preview callback. |
| 73 | */ |
| 74 | void stopPreview(); |
| 75 | |
| 76 | /* Checks if preview is enabled. */ |
| 77 | inline bool isPreviewEnabled() |
| 78 | { |
| 79 | return mPreviewEnabled; |
| 80 | } |
| 81 | |
| 82 | /**************************************************************************** |
| 83 | * Public API |
| 84 | ***************************************************************************/ |
| 85 | |
| 86 | public: |
| 87 | /* Next frame is available in the camera device. |
| 88 | * This is a notification callback that is invoked by the camera device when |
| 89 | * a new frame is available. |
| 90 | * Note that most likely this method is called in context of a worker thread |
| 91 | * that camera device has created for frame capturing. |
| 92 | * Param: |
| 93 | * frame - Captured frame, or NULL if camera device didn't pull the frame |
| 94 | * yet. If NULL is passed in this parameter use GetCurrentFrame method |
| 95 | * of the camera device class to obtain the next frame. Also note that |
| 96 | * the size of the frame that is passed here (as well as the frame |
| 97 | * returned from the GetCurrentFrame method) is defined by the current |
| 98 | * frame settings (width + height + pixel format) for the camera device. |
| 99 | * timestamp - Frame's timestamp. |
| 100 | * camera_dev - Camera device instance that delivered the frame. |
| 101 | */ |
| 102 | void onNextFrameAvailable(const void* frame, |
| 103 | nsecs_t timestamp, |
| 104 | EmulatedCameraDevice* camera_dev); |
| 105 | |
| 106 | /*************************************************************************** |
| 107 | * Private API |
| 108 | **************************************************************************/ |
| 109 | |
| 110 | protected: |
| 111 | /* Adjusts cached dimensions of the preview window frame according to the |
| 112 | * frame dimensions used by the camera device. |
| 113 | * |
| 114 | * When preview is started, it's not known (hard to define) what are going |
| 115 | * to be the dimensions of the frames that are going to be displayed. Plus, |
| 116 | * it might be possible, that such dimensions can be changed on the fly. So, |
| 117 | * in order to be always in sync with frame dimensions, this method is |
| 118 | * called for each frame passed to onNextFrameAvailable method, in order to |
| 119 | * properly adjust frame dimensions, used by the preview window. |
| 120 | * Note that this method must be called while object is locked. |
| 121 | * Param: |
| 122 | * camera_dev - Camera device, prpviding frames displayed in the preview |
| 123 | * window. |
| 124 | * Return: |
| 125 | * true if cached dimensions have been adjusted, or false if cached |
| 126 | * dimensions match device's frame dimensions. |
| 127 | */ |
| 128 | bool adjustPreviewDimensions(EmulatedCameraDevice* camera_dev); |
| 129 | |
| 130 | /* Checks if it's the time to push new frame to the preview window. |
| 131 | * Note that this method must be called while object is locked. */ |
| 132 | bool isPreviewTime(); |
| 133 | |
| 134 | /*************************************************************************** |
| 135 | * Data members |
| 136 | **************************************************************************/ |
| 137 | |
| 138 | protected: |
| 139 | /* Locks this instance for data changes. */ |
| 140 | Mutex mObjectLock; |
| 141 | |
| 142 | /* Preview window instance. */ |
| 143 | preview_stream_ops* mPreviewWindow; |
| 144 | |
| 145 | /* Timestamp (abs. microseconds) when last frame has been pushed to the |
| 146 | * preview window. */ |
| 147 | uint64_t mLastPreviewed; |
| 148 | |
| 149 | /* Preview frequency in microseconds. */ |
| 150 | uint32_t mPreviewAfter; |
| 151 | |
| 152 | /* |
| 153 | * Cached preview window frame dimensions. |
| 154 | */ |
| 155 | |
| 156 | int mPreviewFrameWidth; |
| 157 | int mPreviewFrameHeight; |
| 158 | |
| 159 | /* Preview status. */ |
| 160 | bool mPreviewEnabled; |
| 161 | }; |
| 162 | |
| 163 | }; /* namespace android */ |
| 164 | |
| 165 | #endif /* HW_EMULATOR_CAMERA_PREVIEW_WINDOW_H */ |
| 166 |