| Value | Meaning |
|---|---|
| AV_DEV_TO_APP_NONEMKBETAG!('N', 'O', 'N', 'E') | Dummy message. |
| AV_DEV_TO_APP_CREATE_WINDOW_BUFFERMKBETAG!('B', 'C', 'R', 'E') | Create window buffer message. Device requests to create a window buffer. Exact meaning is device- and application-dependent. Message is sent before rendering first frame and all one-shot initializations should be done here. Application is allowed to ignore preferred window buffer size. @note: Application is obligated to inform about window buffer size with AV_APP_TO_DEV_WINDOW_SIZE message. data: AVDeviceRect: preferred size of the window buffer. NULL: no preferred size of the window buffer. |
| AV_DEV_TO_APP_PREPARE_WINDOW_BUFFERMKBETAG!('B', 'P', 'R', 'E') | Prepare window buffer message. Device requests to prepare a window buffer for rendering. Exact meaning is device- and application-dependent. Message is sent before rendering of each frame. data: NULL. |
| AV_DEV_TO_APP_DISPLAY_WINDOW_BUFFERMKBETAG!('B', 'D', 'I', 'S') | Display window buffer message. Device requests to display a window buffer. Message is sent when new frame is ready to be displayed. Usually buffers need to be swapped in handler of this message. data: NULL. |
| AV_DEV_TO_APP_DESTROY_WINDOW_BUFFERMKBETAG!('B', 'D', 'E', 'S') | Destroy window buffer message. Device requests to destroy a window buffer. Message is sent when device is about to be destroyed and window buffer is not required anymore. data: NULL. |
| AV_DEV_TO_APP_BUFFER_OVERFLOWMKBETAG!('B', 'O', 'F', 'L') | Buffer fullness status messages. Device signals buffer overflow/underflow. data: NULL. |
| AV_DEV_TO_APP_BUFFER_UNDERFLOWMKBETAG!('B', 'U', 'F', 'L') | |
| AV_DEV_TO_APP_BUFFER_READABLEMKBETAG!('B', 'R', 'D', ' ') | Buffer readable/writable. Device informs that buffer is readable/writable. When possible, device informs how many bytes can be read/write. @warning Device may not inform when number of bytes than can be read/write changes. data: int64_t: amount of bytes available to read/write. NULL: amount of bytes available to read/write is not known. |
| AV_DEV_TO_APP_BUFFER_WRITABLEMKBETAG!('B', 'W', 'R', ' ') | |
| AV_DEV_TO_APP_MUTE_STATE_CHANGEDMKBETAG!('C', 'M', 'U', 'T') | Mute state change message. Device informs that mute state has changed. data: int: 0 for not muted state, non-zero for muted state. |
| AV_DEV_TO_APP_VOLUME_LEVEL_CHANGEDMKBETAG!('C', 'V', 'O', 'L') | Volume level change message. Device informs that volume level has changed. data: double: new volume with range of 0.0 - 1.0. |
Message types used by avdevice_dev_to_app_control_message().