1. A method for reducing artifacts in at least one image comprising:
defining a region in at least one first image, the defined region having at least one artifact;
tracking the defined region to at least one second image; and
applying an error diffusion function to the defined region to mask the at least one artifact in the at least one first and second images.
2. The method as in claim 1, wherein the applying step further comprises:
selecting a block size of pixels of the at least one image;
determining if at least one block is within the defined region;
adding a masking signal to the at least one block;
determining a quantization error for the at least one block in the at least one image; and
distributing the quantization error to neighboring blocks.
3. The method of claim 2, further comprising, after the distributing step, encoding the at least one first and second images with a compression function.
4. The method as in claim 3, wherein the compression function is lossy.
5. The method as in claim 2, wherein the adding a masking signal step comprises:
determining a distance of at least one pixel in the at least one block to a boundary of the defined region; and
assigning a value to a masking signal associated to the at least one pixel based on the determined distance.
6. The method as in claim 2, wherein the masking signal is a noise signal.
7. The method as in claim 2, wherein the determining the quantization error step further comprises:
truncating each pixel in the at least one block;
determining a quantization error for each pixel; and
summing the quantization error of each pixel in the at least one block.
8. The method as in claim 1, wherein the tracking step further comprises:
generating a binary mask for the defined region of the at least one first image; and
projecting the binary mask to the at least one second image to track the defined region.
9. The method as in claim 8, wherein the projecting step further comprises estimating the motion of the defined region from the at least one first image to the at least one second image.
10. The method as in claim 9, wherein the estimating step is performed by an affine motion model.
11. The method as in claim 8, wherein the generating step further comprises transforming the defined region into a larger region to capture features of the at least one first image to be tracked.
12. The method as in claim 1, wherein the defining a region step is performed manually by outlining the region or automatically by a detection function.
13. A system for reducing artifacts in at least one image, the system comprising:
a tracking module configured for tracking a defined region in at least one first image to at least one second image, the defined region having at least one artifact; and
an error diffusion module configured for applying an error diffusion function to the defined region to mask the at least one artifact in the at least one first and second images.
14. The system as in claim 13, further comprising a user interface configured for defining the region in the at least one first image.
15. The system as in claim 13, further comprising an encoder configured for encoding the at least one first and second images with a compression function.
16. The system as in claim 13, wherein the error diffusion module further comprises a signal generator configured for generating a masking signal to be applied to at least one image; wherein the error diffusion module is further configured for selecting a block size of pixels of the at least one image, determining if at least one block is within the defined region; determining a quantization error for the at least one block in the at least one image; and distributing the quantization error to neighboring blocks.
17. The system as in claim 16, wherein the signal generator is configured to generate a noise signal.
18. The system as in claim 16, wherein the error diffusion module is further configured for determining a distance of at least one pixel in the at least ones block to a boundary of the defined region; and assigning a value to a masking signal associated to the at least one pixel based on the determined distance.
19. The system as in claim 16, wherein the error diffusion module further comprises a truncation module configured to truncate each pixel in the at least one block, determine a quantization error for each pixel and sum the quantization error of each pixel in the at least one block.
20. The system as in claim 13, wherein the tracking module further comprises a mask generator configured for generating a binary mask for the defined region of the at least one first image; wherein the tracking module is further configured for projecting the binary mask to the at least one second image to track the defined region.
21. The system as in claim 20, wherein the tracking module further comprises a tracking model configured to estimate the motion of the defined region from the at least one first image to the at least one second image.
22. The system as in claim 21, wherein the tracking model is an affine motion model.
23. The system as in claim 20, wherein the tracking module is further configured for transforming the defined region into a larger region to capture features of the at least one first image to be tracked.
24. A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for reducing artifacts in an image, the method comprising:
defining a region in at least one first image, the defined region having at least one artifact;
tracking the defined region to at least one second image; and
applying an error diffusion function to the defined region to mask the at least one artifact in the at least one first and second images.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for forming a casting comprising:
flowing molten metal substantially vertically into a mold by means of a feeder tube;
impeding the flow of oxides that collect at the perimeter of the head of the feeder tube by directing the molten metal through a filter disposed proximate to the end of the feeder tube, wherein said filter has a conical shape and protrudes into a mold cavity of the mold and is held in position by a counter force provided by a divider that protrudes from an opposite side of the mold cavity;
reducing inclusions in the molten metal by inducing laminar flow of the molten metal as it moves through said filter; and
allowing the molten metal to solidify.
2. The method of claim 1 wherein impeding the flow of oxides that collect at the perimeter of the head of the feeder tube comprises filtering the molten metal proximate to the perimeter of the head of the feeder tube.
3. The method of claim 1 wherein inducing laminar flow in the molten metal comprises:
restricting the flow of the molten metal to a progressively smaller cross section as the molten metal proceeds into the mold.
4. The method of claim 1 wherein impeding the flow of oxides and reducing inclusions in the molten metal is accomplished by introducing a filter proximate to the head of the feeder tube wherein the filter is made of a fiberous material that is inert relative to the molten metal and further comprising:
removing excess material that includes the filter from the casting;
smelting the excess material; and
separating the inert filter material from the smelted excess material.