Focus assist system and method
View Patent ↗The invention relates to image focus. In particular, it relates to a focus assist system that conveys focus level data to a user. There are a wide variety of different display methods, including, but not limited to, graphs, highlights, symbols, and varied levels of brightness or color.
1. A method of providing an indication of a degree of focus, comprising:
detecting an image using a two-dimensional array of optical sensors;
converting the detected image signals into a data structure that represents the detected image as a two-dimensional array of pixel values, where the pixel values are representative of an amount of light detected by the optical sensors;
generating a blurred image by combining a selected pixel value with a plurality of pixel values from the vicinity of the selected pixel value;
comparing the selected pixel value with a corresponding blurred image pixel value to determine a degree of focus; and
providing a visual indication of the degree of focus.
2. The method of claim 1 , wherein the visual indication of the degree of focus is overlaid on a representation of the detected image.
3. The method of claim 1 , wherein the visual indication of the degree of focus is adjacent to a representation of the detected image.
4. The method of claim 1 , wherein providing the visual indication of the degree of focus comprises displaying a waveform corresponding to the degree of focus.
5. The method of claim 4 , wherein a point on the waveform corresponds to an average degree of focus for a plurality of vertically aligned pixels.
6. The method of claim 4 , wherein a point on the waveform corresponds to an average degree of focus for a plurality of horizontally aligned pixels.
7. The method of claim 4 , wherein a point on the waveform corresponds to an average degree of focus for a plurality of pixels in a block.
8. The method of claim 4 , wherein a point on the waveform corresponds to an average degree of focus for a plurality of non-adjacent pixels.
9. The method of claim 1 , further comprising determining a degree of focus for a plurality of selected pixels.
10. The method of claim 9 , wherein said plurality of selected pixels define a scan line and wherein providing the visual indication of the degree of focus comprises displaying a waveform corresponding to the degree of focus.
11. The method of claim 10 , wherein a position of said scan line is selected by a user.
12. The method of claim 10 , wherein said scan line comprises a horizontal line.
13. The method of claim 10 , wherein said scan line comprises a vertical line.
14. The method of claim 10 , wherein said scan line comprises a line running at a slope.
15. The method of claim 10 , wherein said scan line comprises a plurality of scan lines.
16. The method of claim 15 , wherein said plurality of scan lines comprises at least one vertical line and at least one horizontal line.
17. The method of claim 15 , wherein said waveform comprises information relating to an average of data from said plurality of scan lines.
18. The method of claim 15 , wherein said waveform comprises a plurality of waveforms, each of said plurality of waveforms corresponding to at least one of said plurality of scan lines.
19. The method of claim 10 , wherein said scan line is greater than a pixel in width.
20. The method of claim 10 , wherein a width of the scan line is selected by a user.
21. The method of claim 10 , wherein said waveform is updated in real-time.
22. The method of claim 1 , wherein providing a visual indication of the degree of focus comprises eliminating noise from said visual indication.
23. An apparatus that assists in adjusting a focus of an image, comprising:
a lens having variable focal length, said lens producing a visual data image from light that enters the lens;
a two-dimensional array of optical sensors that converts the visual data image from the lens into a two-dimensional, digital array of pixel values, where the pixel values are representative of an amount of light detected by the optical sensors;
a processor configured to generate a blurred image by combining a selected pixel value with a plurality of pixel values from the vicinity of the selected pixel value and further configured to compare the selected pixel value with a corresponding blurred image pixel value to determine a degree of focus; and
a display, wherein the display shows the visual data image from the lens and a visual indication of the degree of focus, superimposed on the visual data image and updated contemporaneously with the visual data image.
24. The apparatus of claim 23 , wherein the apparatus is incorporated into a motion picture camera.
25. The apparatus of claim 23 , wherein the visual indication comprises a waveform.
26. The apparatus of claim 23 , wherein the waveform has variable color, with the color variations being indicative of focus level data.
27. The apparatus of claim 23 , wherein the waveform has variable intensity, with the intensity variations being indicative of focus level data.
28. The apparatus of claim 23 , wherein the waveform has variable density, with the density variations being indicative of focus level data.
29. The apparatus of claim 23 , wherein the waveform has variable amplitude, with variations in amplitude being indicative of focus level data.