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/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_CAMERA_CAMERA_CAPTURE_H
#define ANDROID_CAMERA_CAMERA_CAPTURE_H
/*
* Contains declarations for video capturing API that is used by the camera
* emulator.
*/
#include "camera-common.h"
/* Initializes camera device descriptor, and connects to the camera device.
* Param:
* name - On Linux contains name of the device to be used to capture video.
* On Windows contains name to assign to the capturing window. This parameter
* can be NULL, in which case '/dev/video0' will be used as device name on
* Linux, or 'AndroidEmulatorVC' on Windows.
* inp_channel - On Linux defines input channel to use when communicating with
* the camera driver. On Windows contains an index (up to 10) of the driver
* to use to communicate with the camera device.
* Return:
* Initialized camera device descriptor on success, or NULL on failure.
*/
extern CameraDevice* camera_device_open(const char* name, int inp_channel);
/* Starts capturing frames from the camera device.
* Param:
* cd - Camera descriptor representing a camera device opened in
* camera_device_open routine.
* pixel_format - Defines pixel format for the captured frames. Must be one of
* the formats, supported by the camera device.
* width, height - Frame dimensions for the captured video frame. Must match
* dimensions supported by the camera for the pixel format defined by the
* 'pixel_format' parameter.
* Return:
* 0 on success, or non-zero value on failure.
*/
extern int camera_device_start_capturing(CameraDevice* cd,
uint32_t pixel_format,
int frame_width,
int frame_height);
/* Stops capturing frames from the camera device.
* Param:
* cd - Camera descriptor representing a camera device opened in
* camera_device_open routine.
* Return:
* 0 on success, or non-zero value on failure.
*/
extern int camera_device_stop_capturing(CameraDevice* cd);
/* Captures a frame from the camera device.
* Param:
* cd - Camera descriptor representing a camera device opened in
* camera_device_open routine.
* framebuffers - Array of framebuffers where to read the frame. Size of this
* array is defined by the 'fbs_num' parameter. Note that the caller must
* make sure that buffers are large enough to contain entire frame captured
* from the device.
* fbs_num - Number of entries in the 'framebuffers' array.
* r_scale, g_scale, b_scale - White balance scale.
* exp_comp - Expsoure compensation.
* Return:
* 0 on success, or non-zero value on failure. There is a special vaule 1
* returned from this routine which indicates that frames were not available in
* the device. This value is returned on Linux implementation when frame ioctl
* has returned EAGAIN error. The client should respond to this value by
* repeating the read, rather than reporting an error.
*/
extern int camera_device_read_frame(CameraDevice* cd,
ClientFrameBuffer* framebuffers,
int fbs_num,
float r_scale,
float g_scale,
float b_scale,
float exp_comp);
/* Closes camera device, opened in camera_device_open routine.
* Param:
* cd - Camera descriptor representing a camera device opened in
* camera_device_open routine.
*/
extern void camera_device_close(CameraDevice* cd);
/* Enumerates camera devices connected to the host, and collects information
* about each device.
* Apparently, camera framework in the guest will only accept the the YV12
* (V4L2_PIX_FMT_YVU420) pixel format. So, we don't really need to report all the
* pixel formats, supported by the camera device back to the guest. We can simpy
* pick any format that is supported by the device, and collect frame dimensions
* available for it. The only thing we can do is to specifically check, if camera
* support YV12, and choose it, in order to spare some CPU cycles on the
* conversion.
* Param:
* cis - An allocated array where to store informaion about found camera
* devices. For each found camera device an entry will be initialized in the
* array. It's responsibility of the caller to free the memory allocated for
* the entries.
* max - Maximum number of entries that can fit into the array.
* Return:
* Number of entries added to the 'cis' array on success, or < 0 on failure.
*/
extern int enumerate_camera_devices(CameraInfo* cis, int max);
#endif /* ANDROID_CAMERA_CAMERA_CAPTURE_H */
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