video_device.h

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#pragma once

#include <stdint.h>
#include <unistd.h>

#define VIDEO_DEVICE_IMAGE_WIDTH 320
#define VIDEO_DEVICE_IMAGE_HEIGHT 240

struct frame_data {
    uint32_t timestamp;
    uint32_t seq;
    uint32_t bytes;
    uint32_t index;
    void *data;
};

struct buffer {
    void *start;
    size_t length;
};

class VideoDevice
{
public:
    VideoDevice(char const *dev_name, uint32_t n_buffers) :
        _fd(-1), _dev_name(dev_name), _n_buffers(n_buffers), _buffers(nullptr) {}

    ~VideoDevice() = default;

    int start();

    int stop();

    int print_info();

    int get_frame(struct frame_data &frame);

    int put_frame(struct frame_data &frame);

private:
    int _fd;
    const char *_dev_name;
    uint32_t _n_buffers;
    struct buffer *_buffers;

    int open_device();
    int close_device();
    int init_device();
    int init_buffers();
    int init_crop();
    int init_format();
    int start_capturing();
    int stop_capturing();
};