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#ifndef V4L_H
#define V4L_H
#include "linux/videodev.h"
#define DEBUG_OUTPUT(res, text) if(res==-1) { cerr<<__FILE__<<":"<<__LINE__<<" : "; if(text) { cerr<<text<<" : "<<strerror(errno)<<endl; } else { cerr<<strerror(errno)<<endl;} }
#include <string>
#include <vector>
using namespace std;
class V4LDevice {
public:
string file_name;
string name;
};
class V4L {
public:
enum PixelFormat { PX_RGB565, PX_RGB24, PX_YUV420P };
protected:
int v4lfd;
int sem_id;
int current_frame;
string v4l_file_name;
struct video_capability vcap; // capabilities of the video device
vector<video_channel> vchan; // list of video channels
vector<video_audio> achan; // list of audio channels
struct video_mmap *vgrab; // description of each frame (dimension and format)
struct video_buffer vbuf; // description of the video buffer (address, dimension, depth, ...)
struct video_mbuf vmbuf; // description of video buffers mapping (total size, frame offsets, ...)
struct video_window vwind; // description of the overlay video window (location, dimension)
struct video_picture vpic; // description of the video picture (palette, hue, brightness, ...)
unsigned char *capture_memory; // base address of frame data
int capture_memory_size; // base address of frame data
PixelFormat pixel_format;
unsigned int current_video_channel;
unsigned int current_audio_channel;
bool video_preview_enabled;
private:
// these functions are not thread safe
void _setCaptureSize(unsigned int width, unsigned int height);
void _setCurrentAudioChannel(unsigned int);
bool _setPixelFormat(PixelFormat pixel_format);
void _enableAudio(bool on);
void _enableVideoPreview(bool on);
void _close();
public:
// these functions are thread safe
V4L();
~V4L();
vector<V4LDevice> availableDevicesList();
void open(const char *file_name);
void close();
void lock();
void unlock();
string deviceFileName();
string deviceName();
bool isGood();
vector<video_channel> &videoChannels();
unsigned int currentVideoChannel();
void setCurrentVideoChannel(unsigned int);
vector<video_audio> &audioChannels();
unsigned int currentAudioChannel();
void setCurrentAudioChannel(unsigned int);
bool hasVideoPreview();
void enableVideoPreview(bool on);
bool isVideoPreviewEnabled();
void getMinSize(int &width, int &height);
void getMaxSize(int &width, int &height);
void getWindowPosition(unsigned int &x, unsigned int &y);
void getWindowSize(unsigned int &width, unsigned int &height);
void setWindowPositionSize(unsigned int x, unsigned int y, unsigned int width, unsigned int height);
unsigned char *captureFrame();
void setCaptureSize(unsigned int width, unsigned int height);
void getCaptureSize(unsigned int &width, unsigned int &height, int frame=0);
bool setPixelFormat(PixelFormat pixel_format);
PixelFormat pixelFormat();
bool hasAudio();
void enableAudio(bool on);
bool isAudioEnabled();
bool hasTuner();
void setTunerFrequency(unsigned long frequency);
unsigned long tunerFrequency();
};
#endif //V4L_H
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