Taking photo in JPEG_Exif format

[jlysgaard]

Hi,

I'm working on a project and need to tag photos on a N97 using Python.
I found out how to tag JPEG-photos using Exif and to take photos in RGB-format.

The problem is that I can't tag RGB-photos with Exif-information. So I want to take photos in JPEG-format.

I've been searching all over the web but can't find a working example of how to do it.
I found this:

import appuifw, e32
 
 
#Switch to landscape mode
appuifw.app.orientation = "landscape"
 
import camera
 
app_lock = e32.Ao_lock() 
def quit():
	#Release the camera so that other programs can use it
	camera.release()
	app_lock.signal()
appuifw.app.exit_key_handler = quit
 
#Function for taking the picture
def take_picture():
	#Take the photo
	photo = camera.take_photo('JPEG_Exif', (2592, 1944))
	#Save it
	f = open(savepath, "w")
	f.write(photo)
	f.close()
 
savepath = u"C:\\DATA\\photo.jpg"  
#This is the path and name for storing the photo
 
appuifw.app.body = appuifw.Canvas()
 
appuifw.app.menu=[(u"Take photo", take_picture)]
 
app_lock.wait()

Unfortunately the file I get as result can't be read on either my computer or on the phone. It doesn't seem to contain a JPEG-photo.

Please help me. How to take a JPEG-photo using Python on N97

Thanks.

Jonas

[marcelobarrosalmeida]

Hello Jonas

Instead:

#Take the photo
photo = camera.take_photo('JPEG_Exif', (2592, 1944))
#Save it
f = open(savepath, "w")
f.write(photo)
f.close()

Try:

photo = camera.take_photo('JPEG_Exif', (2592, 1944))
photo.save(savepath)

take_photo return an Image object, with several useful functions.

[jlysgaard]

Hi Marcelo,

Thank you for your reply.

The method you are describing works very well if picture-mode is RGB. But as I can see in the page of your first link, the camera returns raw JPEG-data when picture-mode is JPEG_Exif.
If I try to save it using your method I get the message that 'str' does not have a 'save'-method. So it seems the raw JPEG-data is returned as a string.

I would be satisfied with the photos in RGB-format if it wasnøt for the fact that I need to do some Exif-tagging.

Kind regards.
Jonas

[marcelobarrosalmeida]

My fault, Jonas, sorry ...
I did a test here as below and it worked:

photo = camera.take_photo('JPEG_Exif')
f = open("e:\\photo.jpg", "wb")
f.write(photo)
f.close()

Pay attention in the "b". You are saving as text, not binary ! That is the problem.

[jlysgaard]

Thank you SO much, Marcelo.

That did it!

But I'm afraid there's an error here then: http://wiki.forum.nokia.com/index.ph...o_take_a_photo

Once again: thank you for your help. My JPEG-tagging works perfectly now.

Kind regards,
Jonas

[marcelobarrosalmeida]

Yes, same problem. I fixed it as well. Thanks for reporting!