function status = adcm1670_library(command);
%Agilent ADCM-1670 Camera Module Library.
%   STATUS = ADCM1670_LIBRARY(COMMAND);
%
%   Input Parameters:
%   ================
%
%      command -----------> Library function (string):
%                           'open'  - Open communications session.
%                           'init'  - Initialize camera module.
%                           'frame' - Capture current frame.
%                           'close' - Close communications session.
%
%   Output Parameters:
%   =================
%
%      status ------------> Success status (-1 = error, +1 = success).
%
%   See also N/A.

% Stephan Hengstler
% Stanford Wireless Sensor Networks Lab
% December 22, 2005
%
% Last modified: 02-09-2005

%************************ Agilent ADCM-1670 Camera Module Library *************************

%--- Section: Global Variables ------------------------------------------------------------

global		colorm;							% color map
global		handle;							% device handle
global		imager;							% image array
global 		PORT;								% communications port

%--- Section: System Parameters -----------------------------------------------------------

CM_CFG_JPEG_GRAY     = ...             % Configuration: JPEG downsampling gray.
   bin2dec('0010000000000000');
CM_CFG_JPEG_444      = ...             % Configuration: JPEG downsampling 444.
   bin2dec('0010000001000000');
CM_CFG_JPEG_422      = ...             % Configuration: JPEG downsampling 442.
   bin2dec('0010000010000000');

CM_INT_BAUDRATE		= 115200;			% Interface: serial baud rate.

CM_MSK_AEWBFB    		= ...					% Bit mask: Auto exposure/white balance convergence
   hex2dec('00C0');							% 				and frame buffer content.
CM_MSK_IA	     		= ...					% Bit mask: Image abort.
   hex2dec('1000');
CM_MSK_JPEG_CFG      = ...             % Bit mask: JPEG configuration.
   bin2dec('0010000011000000');
CM_MSK_SNAP     		= ...					% Bit mask: Capture snapshot.
   hex2dec('0001');

CM_REG_REV				= '0000';			% Register: IC revision number.
CM_REG_CMD_1			= '0002';			% Register: Main command register 1.
CM_REG_CMD_2			= '0004';			% Register: Main command register 2.
CM_REG_VIDEO_CONFIG	= '000C';			% Register: Video configuration register.
CM_REG_STILL_CONFIG	= '000E';			% Register: Still configuration register.
CM_REG_UART_CREDITS	= '0024';			% Register: UART credits.
CM_REG_SZR_OUT_W_STL = '0032';         % Register: Sizer output width, still mode.
CM_REG_SZR_OUT_H_STL = '0034';         % Register: Sizer output height, still mode.
CM_REG_STATUS_FLAGS	= '0074';			% Register: General status flags.

CM_SEQ_BAUD				= ['55';'55'];		% Sequence: baud rate auto detection.
CM_SEQ_INIT				= ...					% Sequence: image pipeline initialization.
	['00';'00';'20';'04';'00';'02';...	% UART_PCKT_SIZE		The size of one packet.
    '00';'00';'24';'00';'00';'02';...	% UART_CREDITS			Number of current UART credits.
    '00';'00';'0C';'B9';'40';'02';...	% VIDEO_CONFIG			Video configuration.
    '00';'00';'0E';'B9';'40';'02';...	% STILL_CONFIG			Still configuration.
    '00';'00';'26';'01';'60';'02';...	% SZR_IN_W_VID			Sizer input width, video mode.
    '00';'00';'28';'01';'60';'02';...	% SZR_IN_H_VID			Sizer input height, video mode.
    '00';'00';'2A';'01';'60';'02';...	% SZR_OUT_W_VID		Sizer output width, video mode.
    '00';'00';'2C';'01';'60';'02';...	% SZR_OUT_H_VID		Sizer output width, video mode.
    '00';'00';'2E';'01';'60';'02';...	% SZR_IN_W_STL			Sizer input width, still mode.
    '00';'00';'30';'01';'60';'02';...	% SZR_IN_H_STL			Sizer input height, still mode.
    '00';'00';'32';'01';'60';'02';...	% SZR_OUT_W_STL		Sizer output width, still mode.
    '00';'00';'34';'01';'60';'02';...	% SZR_OUT_H_STL		Sizer output height, still mode.
    '00';'00';'3A';'00';'00';'02';...	% UFL_LIMIT_VID		JPEG underflow limit, video mode.
    '00';'00';'3E';'03';'C0';'02';...	% OFL_TARGET_VID		JPEG overflow target, video mode.
    '00';'00';'40';'03';'C0';'02';...	% OFL_LIMIT_VID		JPEG overflow limit, video mode.
    '00';'00';'42';'00';'00';'02';...	% UFL_LIMIT_STL		JPEG underflow limit, still mode.
    '00';'00';'46';'03';'C0';'02';...	% OFL_TARGET_STL		JPEG overflow target, still mode.
    '00';'00';'48';'03';'C0';'02';...	% OFL_LIMIT_STL		JPEG overflow limit, still mode.
    '00';'01';'08';'00';'00';'02'];		% T_DGEN_M				Test data generator mode.

CM_SOP_VIEW_GRAY		= hex2dec('2D');	% Start of packet viewfinder: Y only - grayscale.
CM_SOP_VIEW_JPEG		= hex2dec('30');	% Start of packet viewfinder: JPEG.
CM_SOP_SNAP_GRAY		= hex2dec('4D');	% Start of packet snapshot: Y only - grayscale.
CM_SOP_SNAP_JPEG		= hex2dec('50');	% Start of packet snapshot: JPEG.
CM_SOB_CODE				= hex2dec('11');	% Start of block code.
CM_EOB_CODE				= hex2dec('04');	% End of block code.
CM_EOP_CODE				= hex2dec('02');	% End of packet code.

%--- Command: Open Communications Session -------------------------------------------------

if (~isempty(strmatch('open',command,'exact')))
   
	% open serial port to camera module
	handle 		= com_open(PORT,CM_INT_BAUDRATE);
   if (handle < 0), status = -1, return, end
   
	% perform autobaud detection
	packet 		= char(hex2dec(CM_SEQ_BAUD)');
	status		= com_send(handle,packet);
   if (status < 0), return, end
   
   % return status
   status		= 1;
   
%--- Command: Initialize Camera Module ----------------------------------------------------

elseif (~isempty(strmatch('init',command,'exact')))

	% initialize camera module
	packet 		= char(hex2dec(CM_SEQ_INIT)');
	status		= com_send(handle,packet);
   if (status < 0), return, end

	% configure image output format
	% status		= cm_write_register(handle,CM_REG_VIDEO_CONFIG,'9D80');
	% status		= cm_write_register(handle,CM_REG_STILL_CONFIG,'9D80');

   % enable viewfinder mode
	status		= cm_write_register(handle,CM_REG_CMD_1,'0001');
   if (status < 0), return, end

	% get camera revision id
	camera_id	= cm_read_register(handle,CM_REG_REV)
   
   % return status
   status		= 1;

%--- Command: Capture Current Frame -------------------------------------------------------

elseif (~isempty(strmatch('frame',command,'exact')))

	% repeat until good image (TODO: temporary workaround for corrupt jpeg data)
	while (1)

      % wait until image abort is complete
      while (bitand(hex2dec(cm_read_register(handle,CM_REG_CMD_2)),CM_MSK_IA))
      end
      
      % check auto exposure/white balance convergence and frame buffer content
      while (~bitand(hex2dec(cm_read_register(handle,CM_REG_STATUS_FLAGS)),CM_MSK_AEWBFB))
      end
      
      % capture snapshot
      status		= cm_write_register(handle,CM_REG_CMD_2,dec2hex(CM_MSK_SNAP,4));
   	if (status < 0), return, end
      
      % get image type and size
      type        = hex2dec(cm_read_register(handle,CM_REG_STILL_CONFIG));
      width       = hex2dec(cm_read_register(handle,CM_REG_SZR_OUT_W_STL));
      height      = hex2dec(cm_read_register(handle,CM_REG_SZR_OUT_H_STL));
      
      % initialize image array
      imager 		= [];
      
      % read image data until EOP
      while (1)
         
         % set current uart credits to 1
         status		= cm_write_register(handle,CM_REG_UART_CREDITS,'0001');
		   if (status < 0), return, end
         
         % read-out image data
         packet 		= [];
			timeout		= 0;
			while (isempty(packet) & (timeout < 10))
            pause(0.010)
            packet		= com_recv(handle,1027);
		   	timeout		= timeout + 1;
			end   
         
			% check for error
			if (isempty(packet))
			   status		= -1;
		   	return;
			end

			% convert response packet
         packet 		= dec2hex(bitand(double(packet),255),2);
         
         % check response packet prefix
         switch (hex2dec(packet(1,:)))
            
            % start of block (SOB)?
         case CM_SOB_CODE
            offset        = 2;
            % disp('SOB')
            
            % start of packet (SOP)?
         case {CM_SOP_VIEW_GRAY,CM_SOP_VIEW_JPEG,CM_SOP_SNAP_GRAY,CM_SOP_SNAP_JPEG}
            SOP			  = hex2dec(packet(1,:));
            offset        = 1;
            % disp(['SOP 0x',packet(1,:)])
            
         end
         
         % build image array
         imager		= [imager uint8(hex2dec(packet(offset:end-2,:)))'];
         
         % check response packet suffix
         switch (hex2dec(packet(end-1,:)))
            
            % end of packet (EOP)?
         case CM_EOP_CODE
            % disp('EOP')
            break;
            
            % end of block (EOB)?
         case CM_EOB_CODE
            % disp('EOB')
         end
         
      end
      
      % discard current still frame to avoid double buffering
      status		= cm_write_register(handle,CM_REG_CMD_2,dec2hex(CM_MSK_IA,4));
   	if (status < 0), return, end

      % typecast image array to double
      imager      = double(imager);
      
      % reset warning messages
      lastwarn('');

      % decode image array according to output format
      switch (SOP)
         
         % output format: jpeg
      case {CM_SOP_VIEW_JPEG,CM_SOP_SNAP_JPEG}
         
         % get jpeg downsampling
         type        = bitand(type,CM_MSK_JPEG_CFG);
         
         % add jpeg header to image array
         jpeg        = cmJpgHdrBuild(imager,type,width,height);
         
         % write jpeg image to file
         fid         = fopen(['frame',PORT(end:end),'.jpg'],'w');
         count       = fwrite(fid,jpeg,'uchar');
         status      = fclose(fid);
		   if (status < 0), return, end
         
         % read jpeg image from file
         [imager,colorm]	= imread(['frame',PORT(end:end),'.jpg'],'JPEG');
         
         % output format: y only - grayscale
      case {CM_SOP_VIEW_GRAY,CM_SOP_SNAP_GRAY}
         
         % reshape image array accoding to image size
         imager      = (reshape(imager(1:end-1),width,height))';
         
      end
      
      % check for good image data
      if (isempty(lastwarn))
         break;
      end
   
   end
   
   % typecast image array to double
   imager		= double(imager);

   % return status
   status		= 1;

%--- Command: Close Communications Session ------------------------------------------------

elseif (~isempty(strmatch('close',command,'exact')))

	% close serial port
	com_close(handle);

   % return status
   status		= 1;

%--- Command: Undefined -------------------------------------------------------------------

else

   % return status
   status		= -1;

end