I'm new to the iPhone, I tried to send data up to 256 bytes, but I want to know how to send more than 256 bytes of image data through a push notification.
No. You can not.
The maximum size allowed for a notification payload is 256 bytes; The Apple Push Notification Service refuses any notification that exceeds this limit.
And you need to send the JSON object to the payload.
See Programming Guide for Local and Push Notifications
Notification Payload
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