Circuit and method for modifying a region of an encoded image

Abstract

A video processing circuit includes a processor that receives an encoded image having first and second regions, decodes the first region of the image, modifies the decoded first region, and re-encodes the modified first region. Such a circuit allows one to modify a region of an image by decoding and re-encoding only that region instead of the entire image. For example, if one wishes to overlay an EPG on a bottom portion of a video frame, then the circuit can decode only the EPG and the bottom portion of the frame, overlay the decoded EPG on the bottom frame portion, and re-encode the overlaid bottom frame portion. Therefore, this technique often reduces the processing time, and thus the cost and complexity of the processing circuit, as compared to a circuit that decodes and re-encode the entire frame during an image overlay process.

Description

[0001] This application is a divisional of pending U.S. patent application Ser. No. 09 / 390,241, filed on Sep. 3, 1999, the disclosure of which is incorporated herein in its entirety by reference.TECHNICAL FIELD [0002] The invention relates generally to image-processing techniques, and more particularly to a circuit and method for modifying a region of a encoded image. For example, the invention allows one to blend an electronic program guide (EPG) with a region of an encoded video frame without decoding the entire frame. BACKGROUND OF THE INVENTION [0003]FIG. 1 is a video image 6, which is a video frame that includes a first region 7 and a second region 8. Although described as a video frame for example purposes, the image 6 may also be a video field. Furthermore, although shown as two rectangles in a top-bottom arrangement, the number, shape, and respective locations of these regions is arbitrary. [0004] Typically, one views a sequence of video frames 6 in their respective entireti...

AI Technical Summary

Benefits of technology

"The invention is a video processing circuit that can modify a specific region of an image without decoding and re-encoding the entire image. This reduces processing time and cost. The circuit can also overlay different images or add special effects to the image without affecting the rest of the image."

Problems solved by technology

Therefore, this technique often reduces the processing time, and thus the cost and complexity of the processing circuit, as compared to a circuit that decodes and re-en codes the entire frame during an image overlay process.

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