Peaking headroom for flat panel displays
A focus assist circuit for a viewfinder, including a video amplifier configured to amplify a video signal, a video gain controller configured to adjust gain of the video amplifier to provide peaking headroom, and a peaking processor configured to adjust the amplified video signal. The focus assist circuitry may facilitate focusing a camera lens by proving peaking headroom for a peaking signal that is combined with an amplified signal. The peaking headroom limits the gain applied to a video signal in order to reduce distortions in the peaks. A user interface may include input controls configured to limit the gain of the of a video amplifier.
1. A system for displaying a captured image without distortion, the system comprising:
an image enhancer configured to control a video amplifier based at least on a contrast control signal that controls the video amplifier to amplify a video signal of a captured image to generate an amplified video signal configured to be adjusted to have illuminated peaking signals without being distorted when displayed on a display device; and
a peaking processor configured to adjust the amplified video signal to generate an output video signal with distinguishing illuminated signal peaks to be displayed on the display device without distortion.
2. The system of claim 1 , wherein the image enhancer is further configured to adjust a gain of the video amplifier to provide peaking headroom for the amplified video signal, such that the amplified video signal can be adjusted to have the distinguishing illuminated peaking signals without distortion.
3. The system of claim 2 , wherein the image enhancer comprises a video gain signal generator configured to generate a video gain signal for adjusting the gain of the video amplifier based on the contrast control signal.
4. The system of claim 3 , wherein the image enhancer further comprises a video gain limiter configured to limit the video gain signal based on a percentage of a maximum luminance of the display device.
5. The system of claim 4 , further comprising a user interface having a peaking headroom control that controls the video gain limiter to limit the video gain signal.
6. The system of claim 5 , wherein the user interface is further configured to adjust the contrast control signal in response to a user input instruction.
7. The system of claim 1 , further comprising a signal combiner configured to receive the amplified video signal from the video amplifier, and wherein the peaking processor is further configured to adjust the amplified video signal through the signal combiner to generate the output video signal with distinguishable illuminated signal peaks.
8. The system of claim 1 , further comprising a user interface having a peaking amplitude control configured to control the peaking processor to apply the signal peaks to adjust the amplified video signal to generate the output video signal.
9. The system of claim 1 , wherein the generated output video signal having signal peaks is configured to be displayed on a flat panel display of the display device without distortion.
10. A system for displaying a captured image with at least one enhanced contour, the system comprising:
an image enhancer configured to control a video amplifier based at least on a contrast control signal that controls the video amplifier to amplify a video signal of a captured image, such that the amplified video signal is configured to have at least one enhanced contour without distortion when displayed on a display device; and
an image distortion prevention controller configured to generate an output video signal by adjusting the amplified video signal to have the at least one enhanced contour that is not distorted when the generated output video signal is displayed on the display device.
11. The system of claim 10 , wherein the image enhancer is configured to adjust a gain of the video amplifier to provide peaking headroom for the amplified video signal, such that the amplified video signal is configured to be adjusted to have the at least one enhanced contour without distortion.
12. The system of claim 11 , wherein the image enhancer comprises a video gain signal generator configured to generate a video gain signal for adjusting the gain of the video amplifier based on the contrast control signal.
13. The system of claim 12 , wherein the image enhancer further comprises a video gain limiter configured to limit the video gain signal based on a percentage of a maximum luminance of the display device.
14. The system of claim 13 , further comprising a user interface having a peaking headroom control that controls the video gain limiter to limit the video gain signal.
15. The system of claim 14 , wherein the user interface is further configured to adjust the contrast control signal in response to a user input instruction.
16. The system of claim 10 , further comprising a signal combiner configured to receive the amplified video signal from the video amplifier, and wherein the image distortion prevention controller is further configured to adjust the amplified video signal through the signal combiner to generate the output video signal with the at least one enhanced contour.
17. The system of claim 10 , further comprising a user interface having a peaking amplitude control configured to control the image distortion prevention controller to apply signal peaks to adjust the amplified video signal to generate the output video signal with the at least one enhanced contour based on the applied signal peaks.
18. The system of claim 10 , wherein the generated output video signal is configured to be displayed on a flat panel display of the display device without distortion.
19. A system for displaying a captured image with an enhanced contour, the system comprising:
an enhanced contour generator configured to generate at least one enhanced contour of a captured image when the captured image is emitted based on backlight through a display medium of a display device, the at least one enhanced contour being based on an amplified signal representing the captured image; and
an enhanced contour distortion prevention controller configured to prevent the enhanced contour of the captured image from being distorted by limiting the amplified signal to prevent the captured image with the at least one enhanced contour from exceeding a maximum luminance value of the backlight emitted through the display medium when the captured image with the at least one enhanced contour is displayed through the display medium of the display device.
20. The system of claim 19 , wherein the enhanced contour distortion prevention controller is configured to control a video amplifier based at least on a contrast control signal that controls the video amplifier to limit the amplified signal of the captured image.
21. The system of claim 20 , wherein the enhanced contour distortion prevention controller is configured to adjust a gain of the video amplifier to provide peaking headroom for the amplified signal, such that the amplified signal is configured to be adjusted to have the at least one enhanced contour without distortion.
22. The system of claim 21 , wherein the enhanced contour distortion prevention controller comprises a video gain signal generator configured to generate a video gain signal for adjusting the gain of the video amplifier based on the contrast control signal.
23. The system of claim 22 , wherein the enhanced contour distortion prevention controller further comprises a video gain limiter configured to limit the video gain signal based on a percentage of a maximum luminance of the display device.
24. The system of claim 23 , further comprising a user interface having a peaking headroom control that controls the video gain limiter to limit the video gain signal.
25. The system of claim 24 , wherein the user interface is further configured to adjust the contrast control signal in response to a user input instruction.
26. The system of claim 20 , further comprising a signal combiner configured to receive the amplified signal from the video amplifier, and wherein the enhanced contour generator is further configured to adjust the amplified signal through the signal combiner to generate the at least one enhanced contour of the captured image.
27. The system of claim 20 , further comprising a user interface having a peaking amplitude control configured to control the enhanced contour distortion prevention controller to apply signal peaks to adjust the amplified signal to generate the at least one enhanced contour of the captured image based on the applied signal peaks.
28. The system of claim 19 , wherein the captured image with the at least one enhanced contour is configured to be displayed on a flat panel display of the display device without distortion.
29. The system of claim 19 , wherein the display medium of the display device is liquid crystal.