Categories: S60 | Python | Code Examples

This page was last modified 08:08, 23 April 2008.

From Forum Nokia Wiki

Here is a simple camera application that uses the camera view finder.

There are no zooming or special option. It is free to you to add them depending on your needs.

import appuifw, e32, camera, time
from key_codes import EScancodeSelect, EScancode5, EScancode1, EScancode3
 
if e32.in_emulator( ):
    IMAGEPATH = 'D:\\Images\\%s.png'
else:
    IMAGEPATH = 'E:\\Images\\%s.png'
 
IMAGERESOLUTION = (640, 480)
 
 
# I added this class in the source if you haven't already added it 
# to the libraries.
class Keyboard( object ):
    def __init__( self, onevent=lambda:None ):
        self._keyboard_state = {}
        self._downs = {}
        self._onevent = onevent
 
    def handle_event( self, event ):
        if event['type'] == appuifw.EEventKeyDown:
            code = event['scancode']
            if not self.is_down( code ):
                self._downs[code] = self._downs.get( code, 0 ) + 1
            self._keyboard_state[code] = 1
        elif event['type'] == appuifw.EEventKeyUp:
            self._keyboard_state[event['scancode']] = 0
        self._onevent( )
 
    def is_down( self, scancode ):
        return self._keyboard_state.get( scancode, 0 )
 
    def pressed( self, scancode ):
        if self._downs.get( scancode, 0 ):
            self._downs[scancode] -= 1
            return True
        return False
 
 
# Here is the camera base class I use in few applications.
# This class could be added to your libraries so that you only have to import it.
class Camera( object, appuifw.Canvas ):
    _iImageWidth = 160
    _iImageHeight = 120
    _iSartColor = 0x000000
    _iCapturedColor = 0x0000ff
    _iSavingColor = 0x00ff00
    _iStopedColor = 0xff0000
 
    def __init__( self, aHandleEvent ):
        self._iReady = False
        self._iTempImage = None
        self._iSaving = False
        self._iSaved = False
        self._iViewerActive = False
        appuifw.Canvas.__init__( self, self._redrawCallback, aHandleEvent )
        appuifw.app.body = self
        self._iReady = True
 
    def _redrawCallback( self, aRect=None ):
        self.clear( )
        x = ( self.size[0] - self._iImageWidth ) / 2
        y = ( self.size[1] - self._iImageHeight ) / 2
        if self._iTempImage:
            self.blit( self._iTempImage, target=( x+1, y ) )
 
        if not self._iTempImage:
            color = self._iSartColor
        elif self._iSaving:
            color = self._iSavingColor
        elif self._iSaved:
            color = self._iCapturedColor
        else:
            color = self._iStopedColor
 
        if self._iReady:
            self.line( ( x-2, y-3,x+5, y-3 ), outline=color )
            self.line( ( x-2, y-3,x-2, y+4 ), outline=color )
            self.line( ( self.size[0]-x+2, y-3,self.size[0]-x-4, y-3 ),
                       outline=color )
            self.line( ( self.size[0]-x+3, y-3,self.size[0]-x+3, y+4 ),
                       outline=color )
            self.line( ( x-2, self.size[1]-y+2,x+5, self.size[1]-y+2 ),
                       outline=color )
            self.line( ( x-2, self.size[1]-y-4,x-2, self.size[1]-y+2 ),
                       outline=color )
            self.line( ( self.size[0]-x+2, self.size[1]-y+2,self.size[0]-x-4,
                         self.size[1]-y+2 ), outline=color )
            self.line( ( self.size[0]-x+3, self.size[1]-y-4, self.size[0]-x+3,
                         self.size[1]-y+3 ), outline=color )
 
    def _viewFinderRedrawCallback( self, aImage ):
        self.blit( aImage, target=( (self.size[0] - aImage.size[0])/2 +1,
                                    (self.size[1] - aImage.size[1])/2) )
        self._iTempImage = aImage
 
    def setActive( self ):
        appuifw.app.body = self
        self._redrawCallback( )
 
    def startViewFinder( self ):
        self._iTempImage = None
        self.showCapture( )
        camera.start_finder( self._viewFinderRedrawCallback,
                             size = ( self._iImageWidth, self._iImageHeight ) )
        self._iSaved = False
        self._iViewerActive = True
 
    def stopViewFinder( self ):
        if self._iViewerActive:
            camera.stop_finder( )
            self.showCapture( )
            self._iViewerActive = False
 
    def showCapture(self):
        self._redrawCallback( )
 
    def capture( self ):
        try:
            self._iSaving = True
            self.stopViewFinder( )
            e32.ao_yield( )
            ctime = time.localtime()
            # Filename format: YYYYMMDDHHMMSS
            picName = "%4i%02i%02i%02i%02i%02i" %+ \
                      ((ctime[0]), (ctime[1]), (ctime[2]),\
                       (ctime[3]), (ctime[4]), (ctime[5]))
            img = camera.take_photo( size=IMAGERESOLUTION )
            img.save( IMAGEPATH%picName )
 
            # if thumbnail size is good enough for your application just save
            # the last image:
            # self._iTempImage.save( IMAGEPATH )
            self._iSaved = True
        except Exception, error:
            print error
            self._iSaved = False
        self._iSaving = False
        self.showCapture( )
 
    def isSaved( self ):
        return self._iSaved
 
    def isViewerActive( self ):
        return self._iViewerActive
 
    def __del__( self ):
        if self._iViewerActive:
            camera.stop_finder( )
 
 
# This class, where all the handler are defined, uses both of the classes above.
class CameraView( object ):
    def __init__( self ):
        self._iKeyboard = Keyboard( self._keyObserver )
        self._iCamera = Camera( self._iKeyboard.handle_event )
 
    def setActive( self ):
        self._iCamera.setActive( )
        self._menuDimmer( )
 
    def _keyObserver( self ):
        # select and 5 keys for capture    
        if self._iKeyboard.pressed( EScancodeSelect ) or \
            self._iKeyboard.pressed( EScancode5 ):
            if self._iCamera.isViewerActive():
                self._handleCommands( "CAPTURE" )
 
        # key 1 to start the viewer
        elif self._iKeyboard.pressed( EScancode1 ):
            if not self._iCamera.isViewerActive( ):
                self._handleCommands( "NEW" )
 
        # 3 key for stoping the viewer
        elif self._iKeyboard.pressed( EScancode3 ):
            if self._iCamera.isViewerActive( ) and \
                            not self._iCamera.isSaved( ) :
                self._handleCommands( "STOP" )
 
 
    def _handleCommands( self, aCommand ):
        if aCommand == "NEW":
            self._iCamera.startViewFinder( )
            self._menuDimmer( )
 
        elif aCommand == "STOP":
            self._iCamera.stopViewFinder( )
            self._menuDimmer( )
 
        elif aCommand == "CAPTURE":
            appuifw.note(u'Please wait', 'info', 1)
            self._iCamera.capture( )
            self._menuDimmer( )
            if self._iCamera.isSaved( ):
                appuifw.note(u'Saved', 'info')
            else:
                appuifw.note(u'Failed', 'error')
 
        elif aCommand == "EXIT":
            __exit__()
 
    def _menuDimmer( self ):
        menu = []
        if self._iCamera.isSaved( ):
            menu.append( ( u'New...', lambda:self._handleCommands( "NEW" ) ) )
 
        elif self._iCamera.isViewerActive( ):
            menu.append( ( u'Capture', lambda:self._handleCommands( "CAPTURE" ) ) )
            menu.append( ( u'Stop', lambda:self._handleCommands( "STOP" ) ) )
 
        else:
            menu.append( ( u'New...', lambda:self._handleCommands( "NEW" ) ) )
        menu.append( ( u'Exit', lambda:self._handleCommands( "EXIT" ) ) )
 
        appuifw.app.menu = menu
 
    def __del__( self ):
        # clean exit
        self._iCamera.__del__( )
 
 
def __exit__():
    camView.__del__( )
    APP_LOCK.signal()
 
if __name__ == '__main__':
    APP_LOCK = e32.Ao_lock( )
    appuifw.app.title = u"Cam using View Finder "
    appuifw.app.exit_key_handler = __exit__
    camView = CameraView( )
    camView.setActive( )
    APP_LOCK.wait( )