capture.c

小程序,但是有点用出处的.进攻参考.请多多提意见.

    }
    if (strcmp(arg_list[PAR_VERSION], argv[i]) == 0){
      printf(VERSION);
      return -1;
    }
  } /* for */
  if (!par.toStdout){
    if (npar > 0){
      /* the last is the filename */
      par.fname = argv[argc-1]; 
    }
    else {
      fprintf(stderr, "You must specify a name for the file"
	      " to be written to or specify the option --stdout\n");
    }
  }
  return 0;  
}


/* ---------------------------------------------------------------- */
unsigned int GetTickCount(){
  struct tms t;
  return 1000*times(&t) / sysconf(_SC_CLK_TCK);
}


/* ---------------------------------------------------------------- */
int main(int argc, char *argv[]){
  int fhandler, fhandlerDest, fhandler_background;
  int min_after_background=0;
  int nb, nbw, inx;
  int frame;
  loff_t seek_atual;
  unsigned int tick_start, tick_end;
  long timeSpent;
  float frameRate;
  
  /* default values */
  par.nframes = 1;
  par.toStdout = 0;
  par.forceFileFormat = 0;
  par.fileFormat = FILE_FORMAT_UNKNOWN;
  par.dev = "/dev/fps200";
  par.fname = "stdout";
  par.rect.x = 0;
  par.rect.y = 0;
  par.rect.width = FPS200_WIDTH;
  par.rect.height = FPS200_HEIGHT; 
  par.background = NULL;
  
  if (parse_args(argc, argv) != 0)
    return -1;

  if (calculate_mean){
    size_buffer_mean = sizeof(buffer_mean[0])*sizeof(buffer);
    buffer_mean = (typeof(buffer_mean))malloc(size_buffer_mean);
    if (!buffer_mean){
      fprintf(stderr, "Error: could not allocate memory (%d bytes) to\n"
	      "calculate the average image.\n", size_buffer_mean);
      goto error;
    }
    memset(buffer_mean, 0, size_buffer_mean);
  }

  if (!par.toStdout){
    printf("Number of Frames: %d\n", par.nframes);
    printf("Destination File Name: %s\n", par.fname);
    printf("Source Device: %s\n\n", par.dev);
    printf("Dimension: x=%d y=%d width=%d height=%d\n",
	   par.rect.x, par.rect.y, par.rect.width, par.rect.height);
  }

  if (par.toStdout)
    fhandlerDest = 1;
  else
    fhandlerDest = open(par.fname, O_CREAT | O_TRUNC | O_RDWR, 
			S_IREAD | S_IWRITE);
  if (fhandlerDest >= 0) {
    fhandler = open(par.dev, 0, S_IREAD);
    if (fhandler >= 0){   
      /* select the default values just in case other program change them */
      if (ioctl(fhandler, FPS200_IOCTL_RESET_PARAMETERS, 0) != 0){
	fprintf(stderr, "Error trying to reset the parameters\n");
	goto error;
      }      
      /* change image dimensions */
      if (par.rect.width % 64){
	fprintf(stderr, "Error: the width of the image must"
		" be a multiple of 64\n");
	goto error;
      }
      if ((par.rect.x+par.rect.width) > FPS200_WIDTH){
	fprintf(stderr, "Error: the parameters x=%d and"
		" width=%d are outrange\n", par.rect.x, par.rect.width);
	goto error;
      }
      if ((par.rect.y+par.rect.height) > FPS200_HEIGHT){
	fprintf(stderr, "Error: the parameters y=%d and"
		" height=%d are outrange\n", par.rect.y, par.rect.height);
	goto error;
      }
      if (ioctl(fhandler, FPS200_IOCTL_SETRECT, &par.rect) != 0){
	fprintf(stderr, "Error trying to change the image dimensions\n");
	goto error;
      }
      /* change the file using extension */
      if (!par.forceFileFormat){
	if (strcmp(&par.fname[strlen(par.fname)-4], ".pgm") == 0){
	  if (!par.toStdout)
	    printf("Using the Portable Graymap format\n");
	  if (ioctl(fhandler, FPS200_IOCTL_SETFORMAT, 
		    FPS200_FILEFORMAT_PGM) != 0){
	    fprintf(stderr, "Error trying to change the image file format\n");
	    goto error;
	  }
	}
	else
	  if (strcmp(&par.fname[strlen(par.fname)-4], ".bmp") == 0){
	    if (!par.toStdout)
	      printf("Using the Bitmap Format\n");
	    if (ioctl(fhandler, FPS200_IOCTL_SETFORMAT, 
		      FPS200_FILEFORMAT_BMP) != 0){
	      fprintf(stderr, "Error trying to change the image"
		      " file format\n");
	      goto error;
	    }
	  }
	  else
	    if (strcmp(&par.fname[strlen(par.fname)-4], ".raw") == 0){
	      if (!par.toStdout)
		printf("Using the Raw Format\n");
	      if (ioctl(fhandler, FPS200_IOCTL_SETFORMAT, 
			FPS200_FILEFORMAT_RAW) != 0){
		fprintf(stderr, "Error trying to change the"
			" image file format\n");
		goto error;
	      }
	    }
	    else {
	      if (strcmp(par.fname, "stdout") == 0){
		fprintf(stderr, "When redirecting the output to stdout you "
			"must specify a file format.\nSee --help to more "
			"details.\n");
		
	      }
	      else {
		fprintf(stderr, "No support for the file format "
			"specified (%s)\n", 
			&par.fname[strlen(par.fname)-4]);
	      }
	      goto error;
	    }
      }
      else {
	if (ioctl(fhandler, FPS200_IOCTL_SETFORMAT, 
		  par.fileFormat) != 0){
	  fprintf(stderr, "Error trying to change the"
		  " image file format to %d %s\n", 
		  par.fileFormat,
		  fileFormatName[par.fileFormat]);
	  goto error;
	}
	
      }

      tick_start = GetTickCount();
      for (frame=0; frame < par.nframes; frame++){
	if ((nb=read(fhandler, buffer, sizeof(buffer))) < 0){
	  fprintf(stderr, "Error trying to read the image\n");
	  break;
	}
	else {
	  if (!par.toStdout)
	    printf("frame %d sucessfully read\n", frame);
	  if (calculate_mean){
	    for (inx=0; inx < nb; inx++)
	      buffer_mean[inx] = (buffer_mean[inx] * frame +
		(buffer[inx] & 0xff)) / (frame + 1);

	    if (frame == (par.nframes-1)) {
	      if (par.background){
		fprintf(stderr, "using background image %s to "
			"compute the "
			"final image", par.background);
		fhandler_background = open(par.background, O_RDONLY);
		if (fhandler_background == -1){
		  fprintf(stderr, "Error: Could not open background"
			  " image %s\n", par.background);
		  perror("Error");
		  exit(-1);
		}
		if ((read(fhandler_background, buffer, 
			  sizeof(buffer))) != nb){
		  fprintf(stderr, "Error: Could not read %d bytes"
			  " from the "
			  "background image\n", nb); 
		  perror("Error");
		  exit(-1);
		}
		close(fhandler_background);
		min_after_background = 0;
		for (inx=0; inx < nb; inx++) {
		  buffer_mean[inx] -= buffer[inx];
		  if (buffer_mean[inx] < min_after_background)
		    min_after_background = buffer_mean[inx];
		}
		min_after_background = -min_after_background;
		for (inx=0; inx < nb; inx++) {
		  buffer_mean[inx] += min_after_background;
		  if (buffer_mean[inx] > 255)
		    buffer_mean[inx] = 255;
		}	      
	      }
	      for (inx=0; inx < nb; inx++)
		buffer[inx] = buffer_mean[inx];
	    } /* if it is the last frame */
	  }

	  if (!calculate_mean || (frame == (par.nframes-1)))
	    nbw=write(fhandlerDest, buffer, nb);
	  if (nbw < 0){
	    fprintf(stderr, "Error: Could not perform the"
		    " writing - code=%d\n", nbw);
	    perror("Error: ");
	    break;
	  }
	}
      } /* for */
      tick_end = GetTickCount();

      /* estimates the frame rate */
      if (!par.toStdout){
	timeSpent = tick_end-tick_start;
	if (timeSpent > 0)
	  printf("Total time: %lu ms\n", timeSpent);
	if (timeSpent > 0){
	  frameRate = 1000.0*(float)frame / (float)timeSpent;
	  printf("Frame Rate: %.1f fps\n", frameRate);
	}
      }
      close(fhandler);    
    }
    else {
      perror("Error trying to open the sensor");
      if (errno == ENODEV){
	fprintf(stderr, "The system is reporting that there is"
		" no device in %s.\n"
		"Maybe you forgot to install the driver using the insmod "
		"command or specified a\ndiferent minor number for it.\n", 
		par.dev);
      }
      goto error;
    }
    close(fhandlerDest);
  }
  else {
    fprintf(stderr, "Error: Could not open %s for writing\n", par.fname);
  }     

  if (buffer_mean)
    free(buffer_mean);

  return 0;

 error:
  if (fhandlerDest >= 0)
    unlink(par.fname);
  return -1;
}