gtk_cam.c

gtk实现的图像采集的示例程序。

#include <strings.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <time.h>
#include <gtk/gtk.h>
#include <errno.h>
#include <stdlib.h>

#include "grab-ng.h"
#include "dh-ioctl.h"

//#define __YUV422_CAP__    //采用YUV格式采集

int TOP = 0, LEFT = 0; //窗体起始坐标
int COLS = 768, ROWS = 288;  //采集窗体的大小
int frame = 0;
int send_num = 0;

int bt8x8_handle = 0; //设备句柄
unsigned char *card0_buf = NULL;  //硬件采集到的原始图像数据指针
unsigned char *card0_dest_buf = NULL; //经过格式转换后的图像数据指针

char title[256];

int g_err_num = 0;
int global_frames = 0;  //用来计算FPS
int capture_flag = 0;  //preview采集控制参数
int overlay_flag = 0; //overlay采集控制参数

int b_current = 0, c_current = 0, s_current = 0, h_current = 0; //用来存取图像亮度对比度等参数
GtkObject *b_adj, *c_adj, *s_adj, *h_adj;

time_t stTime;

GtkWidget *main_win;
GtkWidget *status;
GtkWidget *darea;
GtkWidget *label;

gdouble gtk_adjustment_get_value (GtkAdjustment * adjustment);

int send_expose (void);
void on_darea_expose (GtkWidget * widget);
gint configure_event (GtkWidget * widget);
static void overlay_display (void);

//打开设备
void open_dev (void)
{
	int rc;

	card0_dest_buf = (unsigned char *) malloc (768 * 576 * 3); //申请存放处理后图像数据的内存空间
	bt8x8_handle = dh_OpenVideo (0); //打开设备

	if (bt8x8_handle < 0)
	{
		printf (dh_GetErrInfo ());
		free (card0_dest_buf);
		exit (-1);
	}

#ifdef	__YUV422_CAP__
	rc = dh_MSetCaptureNorm (bt8x8_handle, COLS, ROWS, VIDEO_YUYV); //YUV格式采集
#else
	rc = dh_MSetCaptureNorm (bt8x8_handle, COLS, ROWS, VIDEO_BGR24); //BGR格式采集
#endif

	if (rc < 0)
	{
		printf (dh_GetErrInfo ());
	}

	if (dh_SetVideoSource (bt8x8_handle, VIDEO_SOURCE_COMPOSITE0) < 0)	//设置源路为复合视频1
	{
		printf (dh_GetErrInfo ());
	}

	if (dh_SetVideoStandard (bt8x8_handle, VIDEO_MODE_PAL) < 0)	//设置源路制式为PAL制
	{
		printf (dh_GetErrInfo ());
	}

//default value
	dh_SetBrightness (bt8x8_handle, 65535 / 2);
	dh_SetContrast (bt8x8_handle, 65535 / 2);
	dh_SetSaturation (bt8x8_handle, 65535 / 2);
	dh_SetHue (bt8x8_handle, 65535 / 2);

}

/*---------------------------菜单要调用的函数(callback)---------------------------------*/
//菜单项preview要调用的函数
static void preview_display (void)
{
	time (&stTime);
	g_err_num = 0;
	
	//采集之前判断是否有视频信号输入
	if (!dh_IsVideoOn (bt8x8_handle))
	{
		printf ("Video source not ready.\n");
		return;
	}
	
	//如果正在overlay采集,先停止overlay采集
	if (overlay_flag)
		overlay_display ();
	
	//由capture_flag判断开始采集还是停止采集
	if (capture_flag == 0)
	{
		capture_flag = 1;

		//如果窗体大小变化,每次采集前得重新设置采集参数
#ifdef	__YUV422_CAP__
		dh_MSetCaptureNorm (bt8x8_handle, COLS, ROWS, VIDEO_YUYV);
#else
		dh_MSetCaptureNorm (bt8x8_handle, COLS, ROWS, VIDEO_BGR24);
#endif

		dh_MStartCapture (bt8x8_handle, 4); //发往内存循环采集命令,使用4个缓冲区
		gtk_timeout_add (10, (GtkFunction) send_expose, NULL); //每10秒调用一次函数send_expose()
	}
	else
	{
		capture_flag = 0;
		dh_MStopCapture (bt8x8_handle); //停止往内存循环采集
	}
}

//定时器调用的函数,实现连续采集显示
int send_expose (void)
{

	if (capture_flag == 1)
	{
		//返回采集完成当前帧的指针,同时发出采集下帧的命令
		card0_buf = dh_MGetNextFrame (bt8x8_handle);

		if (NULL == card0_buf)
		{
			printf ("card0_buf is NULL.\n");
			//如果采集错误,重启采集
			dh_MStopCapture (bt8x8_handle);
			dh_MStartCapture (bt8x8_handle, 4);
			g_err_num++;
		}
		else
		{
			on_darea_expose (darea); //调用此函数实现图像显示
			//释放内存,否则循环采集无法进行下去
			if (dh_MReleaseBuf (bt8x8_handle) < 0)
			{
				printf (dh_GetErrInfo ());
			}
		}
	}
	return 1;
}

//菜单项overlay调用的函数:往屏幕采集
static void
overlay_display (void)
{
	int wx, wy;

	wx = TOP + 4;
	wy = LEFT + 56;
	
	//采集之前判断是否有视频信号输入
	if (!dh_IsVideoOn (bt8x8_handle))
	{
		printf ("Video source not ready.\n");
		return;
	}
	
	gtk_widget_set_uposition (main_win, TOP, LEFT);

	if (overlay_flag == 0)
	{
		//如果正在preview采集,先停下来
		if(capture_flag)
		{
			capture_flag = 0;
			dh_MStopCapture (bt8x8_handle);
		}
		
		//开始overlay采集
		dh_OStartCapture (bt8x8_handle, COLS, ROWS, wx, wy);
		overlay_flag = 1;
	}
	else
	{	
		//停止overlay采集
		dh_OStopCapture (bt8x8_handle);
		overlay_flag = 0;
	}
}

//菜单项grab调用的的函数抓单帧
static void grab_one_display (void)
{
	int i;
	time (&stTime);
	g_err_num = 0;
	
	//如果正在preview采集,先停下来
	if (capture_flag == 1)
		preview_display ();	//stop capture
	//如果正在overlay采集,先停下来
	if (overlay_flag)
		overlay_display ();

	//采集之前判断是否有视频信号输入
	if (!dh_IsVideoOn (bt8x8_handle))
	{
		printf ("Video source not ready.\n");
		return;
	}
//for(;;)      //死循环抓单帧采集,用来测试性能
	{
		
		card0_buf = dh_MCaptureOne (bt8x8_handle);  //正常抓单帧或单场采集,FPS最高8帧/秒
		//card0_buf = dh_MFastCaptureOne(bt8x8_handle);   //快速抓单帧或单场采集,FPS可达到16帧/秒
		
		//dh_MSnapOne(bt8x8_handle);
		//card0_buf = dh_MGetSnapOneStatus(bt8x8_handle);
		
		if (NULL == card0_buf)
		{
			printf (dh_GetErrInfo ());
			g_err_num++;
		}
		else
		{
			on_darea_expose (darea);   //调用此函数实现图像显示
						
			//释放内存,否则循环采集无法进行下去,如果是快速采集则无需调用此函数
			if (dh_MReleaseBuf (bt8x8_handle) < 0)
			{
				printf (dh_GetErrInfo ());
			}
		}
	}
	gtk_statusbar_push (GTK_STATUSBAR (status), 1, "Grab a picture");
	g_message ("Grab a picture!\n");
}

//此函数用来显示图像和计算FPS
void on_darea_expose (GtkWidget * widget)
{

	static time_t init, end;
	static int frames;

	if (!frames)
	{
		time (&init);
	}

	if (!card0_buf)
	{
		return;
	}

	gdk_threads_enter ();
	
	//转换成24位RGB
#ifdef __YUV422_CAP__
	yuv422_to_rgb24 (card0_dest_buf, card0_buf, COLS * ROWS);
#else
	redblue_swap (card0_dest_buf, card0_buf, COLS * ROWS);
#endif
	//显示图像
	gdk_draw_rgb_image (widget->window, widget->style->white_gc, 0, 0,
			    COLS, ROWS, GDK_RGB_DITHER_NORMAL,
			    card0_dest_buf, COLS * 3);

	gdk_threads_leave ();

	frames++;
	time (&end);
	if (end - init >= 1)
	{
		global_frames = frames;
		frames = 0;
		sprintf (title, "RTime=%d,FPS %d,Err=%d",
			 (int) (end - stTime), global_frames, g_err_num);
		gtk_statusbar_push (GTK_STATUSBAR (status), 1, title);
		fprintf (stderr, "%s\n", title);
	}
}

//退出程序
static void exit_program (void)
{
	int rc = 0;
	capture_flag = 0;

	//退出程序前先释放buf
	if (NULL != card0_buf)
	{
		rc = dh_MReleaseBuf (bt8x8_handle);
		if (rc == 0)
			card0_buf = NULL;
	}

	free (card0_dest_buf);
	dh_CloseVideo (bt8x8_handle);//关闭设备句柄
	gtk_main_quit ();
}

//菜单项option->SourceInput调用下列函数
static void set_ch_video0 ()
{
	dh_SetVideoSource (bt8x8_handle, VIDEO_SOURCE_COMPOSITE0);
	g_message ("use VIDEO_SOURCE_COMPOSITE0.\n");
}

static void
set_ch_video1 (void)
{
	dh_SetVideoSource (bt8x8_handle, VIDEO_SOURCE_COMPOSITE1);
	g_message ("use VIDEO_SOURCE_COMPOSITE1.\n");

}

static void
set_ch_video2 (void)
{
	dh_SetVideoSource (bt8x8_handle, VIDEO_SOURCE_COMPOSITE2);
	g_message ("use VIDEO_SOURCE_COMPOSITE2.\n");
}

static void
set_ch_video3 (void)
{
	dh_SetVideoSource (bt8x8_handle, VIDEO_SOURCE_SVIDEO);
	g_message ("use VIDEO_SOURCE_SVIDEO.\n");
}

//菜单项option->SourceNorm调用下列函数
static void
set_norm_pal (void)
{
	dh_SetVideoStandard (bt8x8_handle, VIDEO_MODE_PAL);
	g_message ("change source norm to PAL.\n");
}

static void
set_norm_ntsc (void)
{
	dh_SetVideoStandard (bt8x8_handle, VIDEO_MODE_NTSC);
	g_message ("change source norm to NTSC.\n");
}

static void
set_norm_secam (void)
{
	dh_SetVideoStandard (bt8x8_handle, VIDEO_MODE_SECAM);
	g_message ("change source norm to SECAM.\n");
}

static void
click_ok (GtkWidget * widget, gpointer window)
{
	dh_GetBrightness (bt8x8_handle, &b_current);
	dh_GetContrast (bt8x8_handle, &c_current);
	dh_GetSaturation (bt8x8_handle, &s_current);