Method and apparatus for image orientation indication and correction
View Patent ↗Tilt imparted to video images captured by a handheld electronic communication device is identified and corrected by the disclosed method and apparatus for image orientation. The handheld device includes image capturing capability and an orientation sensor, which provides a signal representative of orientation relative to gravity to calculate an angle of rotation for the captured images suitable to compensate a difference between the orientation of the handheld device and the orientation relative to gravity. The handheld device also includes a receiver wherein the angle of rotation is recovered and used to determine the changes needed substantially eliminate the difference between the orientation of the captured images and the orientation relative to gravity.
1. A handheld communication device disposed in a housing with at least a first surface and having image capturing capability, comprising:
a processor and associated memory;
an image capture device disposed in the handheld communication device in a known orientation relative to the housing first surface and providing a first signal representing a scene as a first image to said processor;
an orientation sensor providing, to said processor, a first orientation value representing a first orientation of the handheld communication device and a second orientation value representing a second orientation of the handheld communication device, the first orientation value provided before the second orientation value;
wherein said processor receives said first signal from said image capture device and said first orientation value and second orientation value from said orientation sensor, and calculates first and second angles of rotation, the first angle of rotation identifying the difference between said first orientation and said known orientation, the second angle of rotation identifying the difference between said second orientation and said known orientation; and
a communication subsystem coupled to said processor to wirelessly communicate with a network and transmit said first image and said first angle of rotation and, responsive to differences between the first and second angles of rotation, said second angle of rotation.
2. The handheld communication device of claim 1 wherein said second angle of rotation is transmitted to said network when a trigger event has occurred.
3. The handheld communication device of claim 2 further comprising a threshold value stored in said memory and a comparator to compare a difference between the first and second angles of rotation and to generate said trigger event when said difference is greater than said threshold value.
4. The handheld communication device of claim 2 further comprising a timer for generation of said trigger event at predetermined times.
5. A communication system for conveying sequential images between at least two communication devices, comprising:
an image generating communication device that generates a first image of a scene, a first angle of rotation and a second angle of rotation, the first angle of rotation generated based on a first orientation value and the second angle of rotation generated based on a second orientation value, the second orientation value being obtained after the first orientation value, the image generating communication device transmitting the first image, the first angle of rotation and, responsive to differences between the first and second angles of rotation, the second angle of rotation;
a communication network wirelessly coupled to said image generating communication device and receiving said first image, said first angle of rotation and said second angle of rotation;
an image receiving communication device wirelessly coupled to said communication network and receiving, via the communication network, said first image and said first and second angles of rotation, the image receiving communication device configured to determine, based on the first angle of rotation or the second angle of rotation, the changes needed to de-rotate said first image and to display said first image on a display.
6. The communication system of claim 5 further comprising a processor at said image receiving device wherein said processor inserts an indicium into said first image indicating a tilt of said first image.
7. The communication system of claim 5 further comprising a processor at said image receiving device wherein said processor automatically de-rotates said first image.
8. A method for capturing at least one image in a handheld communication device, comprising:
generating a signal representing a first image;
generating a first orientation value representing an orientation of the handheld communication device;
determining a first angle of rotation for said first image based on the first orientation value;
wirelessly communicating with a network to transmit said first image and said first angle of rotation;
generating a second orientation value representing an orientation of the handheld communication device relative to a gravity acceleration vector;
determining a second angle of rotation based on the second orientation value; and responsive to differences between the first angle of rotation and the second angle of rotation, transmitting the second angle of rotation, the second angle of rotation associated with a second image.
9. The method of claim 8 wherein transmitting the second angle of rotation comprises-communicating said second angle of rotation to said network when a trigger event has occurred.
10. The method of claim 9 further comprising:
recalling an angle of rotation threshold value from a memory;
comparing a difference between the first and second angles of rotation to said angle of rotation threshold value; and
generating said trigger event when said difference is greater than said angle of rotation threshold value.
11. The method of claim 9 further comprising generating said trigger event at predetermined times.