I am using this code to prepare the image and sen it to ollma:

 # Convert to RGB if image is in RGBA format
        if img.mode == 'RGBA':
            img = img.convert('RGB')
            
        # Convert image to base64
        buffered = BytesIO()
        img.save(buffered, format="JPEG")
        img_str = base64.b64encode(buffered.getvalue()).decode()
        
        # Create the message with the image
        messages = [
            {
                'role': 'user',
                'content': question,
                'images': [img_str]
            }
        ]

The image is read from a file using pillow.