Source code for camera capture in Linux

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/**/

/* V4lgrab. H */

/**/

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# Ifndef _ v4lgrab_h __

# DEFINE _ v4lgrab_h __

# Define widthbytes (I) (I + 31)/32*4)

# Include <stdio. h>

// Typedef Enum {false = 0, true = 1, o67

// # Define swap_hl_word (x) {(x) = (x) <8) | (x)> 8 );}

// # Define swap_hl_dword (x) {(x) = (x) <24) | (x)> 24) | (X) & 0xff0000)> 8) | (x) & 0xff00) <8 );}

# Define free (x) if (x) {free (x); (x) = NULL ;}

Typedef unsigned char byte;

Typedef unsigned short word;

Typedef unsigned long DWORD;

Typedef struct tagbitmapfileheader {

Word bftype; // the flag of BMP, value is "BM"

DWORD bfsize; // size BMP file, unit is bytes

DWORD bfreserved1; // 0

DWORD bfreserved2; // 0

DWORD bfoffbits; // must be 54

} Bitmapfileheader;

Typedef struct tagbitmapinfoheader {

DWORD bisize; // must be 0x28

DWORD biwidth ;//

DWORD biheight ;//

Word biplanes; // must be 1

Word bibitcount ;//

DWORD bicompression ;//

DWORD bisizeimage ;//

DWORD bixpelspermeter ;//

DWORD biypelspermeter ;//

DWORD biclrused ;//

DWORD biclrimportant ;//

} Bitmapinfoheader;

Typedef struct tagrgbquad {

Byte rgbblue;

Byte rgbgreen;

Byte rgbred;

Byte rgbreserved;

} Rgbquad;

# If defined (_ cplusplus)

Extern "C" {/* Make sure we have C-declarations in C ++ programs */

# Endif

// If successful return 1, or else return 0

Int openvideo ();

Int closevideo ();

// Data space used to store data, size space size

Void getvideodata (unsigned char * data, int size );

# If defined (_ cplusplus)

}

# Endif

# Endif // _ v4lgrab_h ___

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/**/

/* V4lgrab. C */

/**/

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# Include <unistd. h>

# Include <sys/types. h>

# Include <sys/STAT. h>

# Include <fcntl. h>

# Include <stdio. h>

# Include <sys/IOCTL. h>

# Include <stdlib. h>

# Include <Linux/types. h>

# Include <Linux/videodev. h>

# Include "v4lgrab. H"

# Define true 1

# Define false 0

# Define file_video "/dev/video0"

# Define imagewidth 640
# Define imageheight 480

Static int FD;

Static struct video_capability cap;

Static struct video_window win;

Static struct video_picture vpic;

Static struct video_mmap mapbuf;

Int openvideo ()

{

// Open video device

FD = open (file_video, o_rdonly );

If (FD <0 ){

Perror (file_video );

Return (false );

}

// Get capabilities

If (IOCTL (FD, vidiocgcap, & Cap) <0 ){

Perror ("vidiogcap ");

Printf ("(" file_video "not a video4linux device ?) \ N ");

Close (FD );

Return (false );

}

Printf ("devicename --> % s \ n", Cap. Name );
Printf ("devicetape --> % d \ n", Cap. type );
Printf ("channels --> % d \ n", Cap. channels );
Printf ("maxwidth --> % d \ n", Cap. maxwidth );
Printf ("maxheith --> % d \ n", Cap. maxheight );
Printf ("minwidth --> % d \ n", Cap. minwidth );
Printf ("minheith --> % d \ n", Cap. minheight );

// Get the video overlay window

If (IOCTL (FD, vidiocgwin, & Win) <0 ){

Perror ("vidiocgwin ");

Close (FD );

Return (false );

}

// Set the video overlay window

Win. width = imagewidth;

Win. Height = imageheight;

If (IOCTL (FD, vidiocswin, & Win) <0 ){

Perror ("vidiocswin ");

Close (FD );

Return (false );;

}

// Get picture Properties

If (IOCTL (FD, vidiocgpict, & vpic) <0 ){

Perror ("vidiocgpict ");

Close (FD );

Return (false );

}

// Mapbuf. width = 600;
// Mapbuf. Height = 480;

If (cap. Type & vid_type_monochrome ){

} Else {

Vpic. Depth = 32;
// The common color depth is 1-bit, 8-bit, 24-bit, and 32-bit. One digit has two possible values: 0 or 1. A large color depth (more bits per pixel) means that a digital image has more available colors and more precise color representation.
Vpic. palette = video_palette_rgb24;
Vpic. brightness = 5000; // 3000-12000 is suitable
Vpic. Color = 65535;
Vpic. Whiteness = 65535; // 65-65535 is slightly different
If (IOCTL (FD, vidiocspict, & vpic) <0 ){

Printf ("unable to find a supported capture format. \ n ");

Return (false );

}

}

Return (true );

}

Int closevideo ()

{

If (FD! =-1 ){

Close (FD );

Return (true );

}

Return (false );

}

Void getvideodata (unsigned char * data, int size)

{

Size = read (FD, Data, size );

}

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/**/

/* Temp_get.c */

/**/

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# Include <unistd. h>
# Include <sys/types. h>
# Include <sys/STAT. h>
# Include <fcntl. h>
# Include <stdio. h>
# Include <sys/IOCTL. h>
# Include <stdlib. h>
# Include <Linux/types. h>
# Include <Linux/videodev. h>
# Include "v4lgrab. H"

# Define BMP "image2.bmp"

# Define imagewidth 640
# Define imageheight 480

Int main (INT argc, char ** argv)

{

File * FP;

Bitmapfileheader BF;

Bitmapinfoheader Bi;

Unsigned char * buffer;

Int I;

Fp = fopen (BMP, "WB ");

If (! FP ){

Perror (BMP );
Exit (1 );

}


If (openvideo () =-1 ){

Return (-1 );

}

// Set bitmapinfoheader

Bi. bisize = 40;

Bi. biwidth = imagewidth;

Bi. biheight = imageheight;

Bi. biplanes = 1;

Bi. bibitcount = 24;

Bi. bicompression = 0;

Bi. bisizeimage = widthbytes (Bi. biwidth * bi. bibitcount) * bi. biheight;

Bi. bixpelspermeter = 0;

Bi. biypelspermeter = 0;

Bi. biclrused = 0;

Bi. biclrimportant = 0;

// Set bitmapfileheader

BF. bftype = 0x4d42;

BF. bfsize = 54 + bi. bisizeimage;

BF. bfreserved1 = 0;

BF. bfreserved2 = 0;

BF. bfoffbits = 54;

Buffer = malloc (Bi. bisizeimage );

If (! Buffer ){

Printf ("out of memory. \ n ");

Exit (1 );

}

For (I = 0; I <20; I ++)

Getvideodata (buffer, Bi. bisizeimage );

Fwrite (& BF, 14, 1, FP );

Fwrite (& BI, 40, 1, FP );

Fwrite (buffer, Bi. bisizeimage, 1, FP );

Printf ("Get BMP form video \ t [OK] \ n ");

Fclose (FP );

Closevideo ();

Return 0;

}

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Extracted from the net, after debugging modification. In gcc4.1 arm-linux-gcc-3.4.1 compiled through.
It can run normally on the S3C2410 PC.