Automatic engraving method and apparatus

• US 5,329,381 A
• Filed: 02/20/1992
• Issued: 07/12/1994
• Est. Priority Date: 02/20/1992
• Status: Expired due to Term

• Current Assignee: John H. Payne
• Original Assignee: John H. Payne
• Inventors: Payne, John H.
• Primary Examiner(s): Coles, Sr., Edward L.
• Assistant Examiner(s): Grant, II, Jerome
• Application Number:
  US07/839,403
• Time in Patent Office: 873 Days
• Field of Search: 430/269, 101/150, 358/299, 358/443, 358/447, 358/296, 358/401, 358/455, 358/456, 358/474, 358/463, 358/471, 156/345
• US Class Current: 358/3.29
• CPC Class Codes: B33Y 50/00 Data acquisition or data processing for additive manufacturing
• CPC Class Codes: H04N 1/32561 using a programmed control device, e.g. a microprocessor
• CPC Class Codes: H04N 1/40093 Modification of content of picture, e.g. retouching geometric modifications H04N1/387

Abstract

An automatic engraving system scans an image such as a photograph, samples and resizes the image to provide a masterized gray scale data base of the image. The image is then logarithmically corrected and noise is removed from the image using the Outlier noise reduction method. The Outlier noise reduced image is then smoothed and edge detection methods are used to provide an output that represents the initial image filtered smoothed and edge detected. The edge detection image is then converted to a bilevel image using thresholding. The bilevel image is then converted to a vector form and speckle noise removed. The speckle noise removed image is then converted to a vector engraving file which is sent to an engraving machine. The engraving process then can batch create one or more than one image or multiple numbers of a single image. The output can be printed rather than engraved to produce the artistic effect of traditional engraving on paper.

Claims

1. A method of automatic engraving comprising the steps of:

(a) scanning an image to create a database of image points;

(b) logarithmically correcting each point of the image;

(c) performing edge detection on the image database to produce an edge detection image database;

(d) performing a raster-to-vector conversion of the edge detection image database to generate a vector database; and

(e) converting the vector database to a vector engraving file.

2. The method of claim 1 further including the step of resampling and resizing the database of image points.

3. The method of claim 1 further including the step of performing thresholding on the edge detection image database.

4. The method of claim 1 further including the step of performing a bilevel image conversion to produce a bilevel image output of the edge detection image database.

5. The method of claim 1 further including the step of removing speckle noise from the edge detection image database.

6. The method of claim 1 wherein the edge detection step further comprises the Marr-Hildreth "Mexican Hat" filter.

7. The automatic engraving method of claim 1 wherein the image is copied to an engraving directory.

8. The automatic engraving method of claim 1 wherein the step of converting the vector database to a vector engraving file further comprises the step of storing the vector engraving file in a plot directory capable of compiling a plurality of vector engraving files and second the plot directory to an engraving device to produce a plurality of different engravings.

9. The method of claim 1 further including the step of performing noise reduction on the logarithmic correction of the image.

10. The method of claim 9 wherein the noise reduction step is carried out according to an Outlier noise reduction method.

11. A method of automatic engraving comprising the steps of:

(a) scanning an image;

(b) resampling and resizing the image;

(c) logarithmically correcting each point of the image;

(d) performing Outlier noise reduction on the logarithmic correction of the image;

(e) smoothing the Outlier noise reduction image and producing a smoothed image;

(f) performing edge detection on the smoothed image to produce an edge detection image;

(g) performing thresholding on the edge detection image to produce a threshold output;

(h) performing a bilevel image conversion to produce a bilevel image output;

(i) performing a raster-to-vector conversion of the bilevel image output to produce a raster-to-vector converted image; and

(j) converting the raster-to-vector converted image to a vector engraving file.

12. The method of claim 11 wherein the edge detection step further comprise the Marr-Hildreth "Mexican Hat" filter.

13. The automatic engraving method of claim 11 wherein the step of converting the raster-to-vector converted image to a vector engraving file further comprises the step of storing the vector engraving file in a plot directory capable of compiling a plurality of vector engraving files and sending the plot directory to an engraving device to produce a plurality of different engravings.

14. A method of automatic printing comprising the steps of:

(a) scanning an image;

(b) resampling and resizing the image;

(c) logarithmically correcting each point of the image;

(d) performing Outlier noise reduction on the logarithmic correction of the image;

(e) smoothing the Outlier noise reduction image and producing a smoothed image;

(f) performing edge detection on the smooth image to produce an edge detection image;

(g) performing thresholding on the edge detection image to produce a threshold output;

(h) performing a bilevel image conversion to produce a bilevel image output;

(i) printing an object that resembles the image.

15. A method of automatic printing comprising the steps of:

(a) scanning an image to create a database of image points;

(b) logarithmically correcting each point of the image;

(c) performing edge detection on the image database to produce an edge detection image database;

(d) performing a raster-to-vector conversion of the edge detection image database to generate a vector database; and

(e) printing an object that resembles the image.