v4l2capture.h

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/*
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */
//========================================================================
//
// Desc: Own helper functions for capturing from v4l2 device
// Author: Marcin Rudowski
// Email: mar_rud@poczta.onet.pl
// Date: 19 Jun 2006
//
//
// NOTE: this was based on similar library for v4l:
//  Project:        libfg - Frame Grabber interface for Linux
//  Author:         Gavin Baker <gavinb@antonym.org>
//  Homepage:       http://www.antonym.org/libfg
//--------------------------------------------------------------------------

//========================================================================
#ifndef __V4L2CAPTURE__H_
#define __V4L2CAPTURE__H_


#ifdef __cplusplus
extern "C"
{
#endif


#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>

#include <sys/mman.h>
#include <sys/ioctl.h>

#include <linux/fs.h>
#include <linux/kernel.h>
#include <asm/types.h>          /* for videodev2.h */
#include <linux/videodev.h>


//==========================================================================
//  Definitions
//==========================================================================

// Standard device for fg2_open()
#define FG_DEFAULT_DEVICE       "/dev/video0"

// Normal capture size
#define FG_DEFAULT_WIDTH        640
#define FG_DEFAULT_HEIGHT       480

// Default input sources
#define FG_SOURCE_TV            0
#define FG_SOURCE_COMPOSITE     1
#define FG_SOURCE_SVIDEO        2


struct my_buffer
{
    int id;
    void * start;
    size_t length;
    struct v4l2_buffer *buf;
};


typedef struct
{
    char*                       device;     // Device name, eg. "/dev/video"
    int                         fd;         // File handle for open device
    struct v4l2_capability      caps;       // Capabilities
    unsigned int                numOfIn;    // Number of Inputa
    struct v4l2_input*          sources;    // Input sources (eg. TV, SVideo)
    int                         source;     // Currently selected source
    struct v4l2_format          frmt;       // pixel format
    struct my_buffer            *buffers;   // memory mapped buffer
    unsigned int                n_buffers;

    struct v4l2_queryctrl       *controls;   // various countrols like brighteness etc
    unsigned int                numOfCtls;  // size of controls tab

    int                         isCapturing;
    unsigned int                pix_fmt;
    unsigned int                width;
    unsigned int                height;
    enum v4l2_field             field;
    int                         depth;
    enum v4l2_field             altField; // current field type in alternate mode




    struct v4l2_tuner          tuner;      // TV or Radio tuner
    int                         cur_frame;  // Currently capuring frame no.

} FRAMEGRABBER2;




//==========================================================================
//                  General access functions
//==========================================================================


FRAMEGRABBER2* fg2_createFrameGrabber();


void fg2_delete(FRAMEGRABBER2** fg);


int fg2_open( FRAMEGRABBER2* fg, const char *dev);

//==========================================================================
//                  Capturing
//==========================================================================


int fg2_startCapture(FRAMEGRABBER2* fg);

int fg2_stopCapture(FRAMEGRABBER2* fg);



struct my_buffer *getFrameBuffer( FRAMEGRABBER2* fg );


void giveBackFrameBuffer( FRAMEGRABBER2* fg, struct my_buffer *mBuff);


//==========================================================================
//                  Source selection
//==========================================================================

int fg2_get_source_count( FRAMEGRABBER2* fg );

int fg2_get_source_id( FRAMEGRABBER2* fg);

const char* fg2_get_source_name( FRAMEGRABBER2* fg);

const char* fg2_get_id_source_name( FRAMEGRABBER2* fg, int src );

const char * fg2_get_device_name( FRAMEGRABBER2* fg );

int fg2_set_source( FRAMEGRABBER2* fg, int src, const char *strSrc );


//==========================================================================
//                  Changing settings by controls
//==========================================================================

int fg2_countControls( FRAMEGRABBER2* fg);

int fg2_setControlValueI( FRAMEGRABBER2* fg, int id, double val);
int fg2_setControlValue( FRAMEGRABBER2* fg, const char *id, double val);

double fg2_getControlValueI( FRAMEGRABBER2* fg, int id);
double fg2_getControlValue( FRAMEGRABBER2* fg, const char *id);


const char *fg2_getControlName( FRAMEGRABBER2* fg, int id);

//==========================================================================
//                  Other settings
//==========================================================================


int fg2_set_source_norm( FRAMEGRABBER2* fg, v4l2_std_id norm );


int fg2_setPixelSettings( FRAMEGRABBER2* fg, int width, int height,
                          unsigned int fmt, enum v4l2_field fld, int depth );



#ifdef __cplusplus
}
#endif

#endif /* __CAPTURE__H_ */

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