F2/V4L2Sensor.h

#ifndef FCAM_V4L2_SENSOR_H
#define FCAM_V4L2_SENSOR_H

#include "../Frame.h"
#include <vector>
#include <string>
#include <map>

namespace FCam { namespace F2 {

    // This class gives low-level control over the sensor using the
    // V4L2 interface. It is used by the user-visible sensor object to
    // control the sensor

    class V4L2Sensor {
      public:

        struct V4L2Frame {
        Time processingDoneTime;
        unsigned char *data;
        size_t length; // in bytes
        int index;    
    };

    struct Mode {
        int width, height;
        ImageFormat type;
    };

    static V4L2Sensor *instance(std::string);

    // open and close the device
    void open();
    void close();

    // start and stop streaming
    void startStreaming(Mode, 
                HistogramConfig *,
                SharpnessMapConfig *);
    void stopStreaming();

    V4L2Frame *acquireFrame(bool blocking);
    void releaseFrame(V4L2Frame *frame);

    Mode getMode() {return currentMode;}

    enum Errors {
        InvalidId,
        OutOfRangeValue,
        ControlBusy
    };

    void setControl(unsigned int id, int value);
    int getControl(unsigned int id);

    void setExposure(int);
    int getExposure();

    void setFrameTime(int);
    int getFrameTime();

    void setGain(float);
    float getGain();

    void getHistogram(Time t, Histogram *stats, HistogramConfig *conf);
    void setHistogramConfig(HistogramConfig *);

    void getSharpnessMap(Time t, SharpnessMap *stats, SharpnessMapConfig *conf);
    void setSharpnessMapConfig(SharpnessMapConfig *);

    int getFD();
       
      private:
    void wipeHistogram(Histogram *);
    void wipeSharpnessMap(SharpnessMap *);

    V4L2Sensor(std::string);

    Mode currentMode;
    SharpnessMapConfig currentSharpness;
    HistogramConfig currentHistogram;

    std::vector<V4L2Frame> buffers; 

    enum {CLOSED=0, IDLE, STREAMING} state;
    int fd;

    std::string filename;

    // there is one of these objects per device
    static std::map<std::string, V4L2Sensor *> instances_;
    };

}}

#endif

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