T.V. Special effects generator

• US 4,334,245 A
• Filed: 08/26/1980
• Issued: 06/08/1982
• Est. Priority Date: 03/17/1977
• Status: Expired due to Term

• Current Assignee: Quantel Limited 37 Victoria Avenue Southend On Sea Essex
• Original Assignee: Micro Consultants Ltd. (Belden Inc.)
• Inventors: Michael, Peter C.
• Primary Examiner(s): Richardson, Robert L.
• Application Number:
  US06/181,500
• Time in Patent Office: 651 Days
• Field of Search: 358/22, 358/182, 358/183, 358/180, 358/185
• US Class Current: 348/581
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation
• CPC Class Codes: H04N 5/275 Generation of keying signals

Abstract

A T.V. special effects generator which includes a store for a video image and a coefficient processor connected to the store which synthesises picture points from the stored video image to provide a processed image which has a shape dependent on mask data controlling this picture point synthesis which results in an image distorted into the desired shape to give a fish-eye effect for example. The mask data may be generated in a computer or by using a T.V. camera and the processed mask information may be used as the key input in a studio mixer. Additional control of the size of the image can be effected to provide picture zoom.

Claims

1. A television special effects generator comprising:

video image storage means for storing a video image;

mask data means for providing mask shape information representative of a masking shape; and

coefficient processing means for receiving and processing the stored video image to provide an image of modified shape comprised of a plurality of picture points each synthesised from adjacent picture point information in dependence on masking shape information provided by said mask data means.

2. A generator according to claim 1, wherein the mask data means comprises a picture source representative of said mask derived from a video camera cooperating with a visual representation of the desired mask shape.

3. A generator according to claim 1, wherein the mask data means comprises a computer for generating the desired mask data.

4. A generator according to claim 1, including mask storage means for storing the provided mask shape information received from said mask data means.

5. A generator according to claim 1, including variable control means connected to said coefficient processing means to provide variation in the size of the processed image relative to normal frame size.

6. A generator according to claim 4, wherein the image storage means comprises a digital store and the mask data storage means comprises a digital data store for holding data on the desired mask dimensions.

7. A generator according to claim 4, wherein the image storage means and mask data storage means each comprise a digital picture store.

8. A generator according to claim 7, wherein an analogue to digital converter is provided to convert an analogue video signal into digital form prior to receipt by the digital stores.

9. A generator according to claim 7, wherein the video mask data in said mask data storage means is generated by means of a computer connected to said store.

10. A generator according to claim 1, wherein the coefficient processing means include a coefficient store for storing different coefficients to modify the picture dimensions in dependence on the coefficients selected according to the mask image information.

11. A generator according to claim 10, wherein a coefficient modifier is provided for modifying the information derived from said mask data means to effect a change in size of the processed video image by modifying the coefficients selected from said coefficient store.

12. A generator according to claim 11, wherein variable control means are provided connected to the coefficient modifier to allow selective size change of the processed image to be obtained.

13. A generator according to claim 12, wherein the variable control means is connected to the coefficient modifier via an analogue to digital converter.

14. A generator according to claim 1, wherein generator means are provided to generate a key output dependent on mask image data derived from said processing means for use in a mixer.

15. A generator according to claim 14, wherein the generator means includes a digital to analogue converter.

16. A generator according to claim 1, wherein detector means are provided to detect the presence of the mask shape information in the form of a keying signal to control the coefficient processing means.

17. A generator according to claim 15, wherein the detector means includes a counter for determining the period for which the keying signal is present on a line by line basis.

18. A generator according to claim 1, wherein scrolling means are provided to effect scrolling of the video image stored in the storage means.

19. A generator according to claim 5, wherein the computer is adapted to generate data on one of a plurality of masks stored therein.

20. A generator according to claim 1, including first masks storage means for storing the provided mask shape information for a first mask shape, second mask storage means for storing mask shape information for a second mask shape and change over means for providing a gradual change over from the first to the second mask shape in a predetermined period.

21. A generator according to claim 20, including selector means coupled to said change over means for selecting the period to effect complete change over.

22. A generator according to claim 21, wherein the change over means includes a subtractor for receiving the information from the first and second mask storage means, a divider for dividing the subtracted output by the number of frames designated by said selector means, a multiplier for multiplying the divided output by the number of frames which have occurred in the sequence, and an adder for adding the multiplier output with the information from the first mask storage means.

23. A method of generating television special effects comprising:

storing an incoming video image;

providing mask shape information representative of a desired masking shape; and

processing the stored video image to provide an image of modified shape comprised of a plurality of picture points each synthesised from adjacent picture point information in dependence on the masking shape information provided.

24. A method according to claim 23, wherein the mask shape information is derived from a video camera cooperating with a visual representation of the desired mask shape.

25. A method according to claim 23, wherein the mask shape information is derived from a computer for generating the desired mask data.

26. A method according to claim 23, including the step of variably controlling the processing to provide selective variation in the size of the processed image relative to normal frame size.

27. A method according to claim 23, wherein mask shape information representative of two desired masking shapes is provided and gradual change over from one to the other of said shapes is effected in a predetermined period.

28. A method according to claim 27, including the step of selecting the period for the change over to be effected.

29. A method according to claim 28, wherein the change over step includes calculating any difference between the information entering the two mask shapes, dividing the difference by the number of frames required to occur in the selected change over period and multiplying the divided output by the number of frames which have occurred during the change over period and adding the result to information on the first mask shape.