可將多個(gè) Femto Mega 設(shè)備連接到計(jì)算機(jī)。首先，我們將使用 k4a_device_get_installed_count() 函數(shù)確定有多少個(gè)設(shè)備，或者是否連接了任何設(shè)備。此函數(shù)應(yīng)可立即運(yùn)行，而無需經(jīng)過附加的設(shè)置。

uint32_t count = k4a_device_get_installed_count();

確定某個(gè)設(shè)備已連接到計(jì)算機(jī)后，可以使用 k4a_device_open() 將其打開。可以提供想要打開的設(shè)備的索引，或者只對第一個(gè)設(shè)備使用 K4A_DEVICE_DEFAULT。

// Open the first plugged in Kinect device
k4a_device_t device = NULL;
k4a_device_open(K4A_DEVICE_DEFAULT, &device);

與 Azure Kinect 庫中的大多數(shù)內(nèi)容一樣，當(dāng)你打開某種內(nèi)容時(shí)，也應(yīng)該在用完時(shí)將其關(guān)閉！關(guān)閉時(shí)，請記得調(diào)用 k4a_device_close()。

k4a_device_close(device);

打開設(shè)備后，可以進(jìn)行測試以確保它正常工作。讓我們讀取設(shè)備的序列號！

// Get the size of the serial number
size_t serial_size = 0;
k4a_device_get_serialnum(device, NULL, &serial_size);
// Allocate memory for the serial, then acquire it
char *serial = (char*)(malloc(serial_size));
k4a_device_get_serialnum(device, serial, &serial_size);
printf("Opened device: %s\n", serial);
free(serial);

啟動相機(jī)

打開設(shè)備后，需要使用 k4a_device_configuration_t 對象配置相機(jī)。相機(jī)配置包含大量不同的選項(xiàng)。請選擇最適合自己方案的設(shè)置。

// Configure a stream of 3840x2160 BRGA color data at 15 frames per second
k4a_device_configuration_t config = K4A_DEVICE_CONFIG_INIT_DISABLE_ALL;
config.camera_fps       = K4A_FRAMES_PER_SECOND_15;
config.color_format     = K4A_IMAGE_FORMAT_COLOR_BGRA32;
config.color_resolution = K4A_COLOR_RESOLUTION_2160P;
// Start the camera with the given configuration
k4a_device_start_cameras(device, &config);
// ...Camera capture and application specific code would go here...
// Shut down the camera when finished with application logic
k4a_device_stop_cameras(device);

錯誤處理

為簡潔起見，我們不會在某些例子中顯示錯誤處理。但是，錯誤處理始終很重要！許多函數(shù)返回常規(guī)的成功/失敗類型 k4a_result_t，或者包含詳細(xì)信息的更具體的變量，比如 k4a_wait_result_t。請查看每個(gè)函數(shù)的文檔或 IntelliSense，以了解該函數(shù)預(yù)期顯示的錯誤消息！

可以使用 K4A_SUCCEEDED 和 K4A_FAILED 宏檢查函數(shù)的結(jié)果。因此，除了打開 Femto Mega 設(shè)備以外，我們還可以按如下所示保護(hù)函數(shù)調(diào)用：

// Open the first plugged in Kinect device
k4a_device_t device = NULL;
if ( K4A_FAILED( k4a_device_open(K4A_DEVICE_DEFAULT, &device) ) )
{
    printf("Failed to open k4a device!\n");
    return;
}

完整源代碼

#pragma comment(lib, "k4a.lib")
#include <k4a/k4a.h>
#include <stdio.h>
#include <stdlib.h>
int main()
{
    uint32_t count = k4a_device_get_installed_count();
    if (count == 0)
    {
        printf("No k4a devices attached!\n");
        return 1;
    }
    // Open the first plugged in Kinect device
    k4a_device_t device = NULL;
    if (K4A_FAILED(k4a_device_open(K4A_DEVICE_DEFAULT, &device)))
    {
        printf("Failed to open k4a device!\n");
        return 1;
    }
    // Get the size of the serial number
    size_t serial_size = 0;
    k4a_device_get_serialnum(device, NULL, &serial_size);
    // Allocate memory for the serial, then acquire it
    char *serial = (char*)(malloc(serial_size));
    k4a_device_get_serialnum(device, serial, &serial_size);
    printf("Opened device: %s\n", serial);
    free(serial);
    // Configure a stream of 3840x2160 BRGA color data at 15 frames per second
    k4a_device_configuration_t config = K4A_DEVICE_CONFIG_INIT_DISABLE_ALL;
    config.camera_fps       = K4A_FRAMES_PER_SECOND_15;
    config.color_format     = K4A_IMAGE_FORMAT_COLOR_BGRA32;
    config.color_resolution = K4A_COLOR_RESOLUTION_2160P;
    // Start the camera with the given configuration
    if (K4A_FAILED(k4a_device_start_cameras(device, &config)))
    {
        printf("Failed to start cameras!\n");
        k4a_device_close(device);
        return 1;
    }
    // Camera capture and application specific code would go here
    // Shut down the camera when finished with application logic
    k4a_device_stop_cameras(device);
    k4a_device_close(device);
    return 0;
}

后續(xù)步驟

了解如何使用傳感器 SDK 查找并打開 Femto Mega 設(shè)備查找并打開設(shè)備。