Obviousness

An analysis of U.S. Patent 12,160,681 under 35 U.S.C. § 103 reveals that its independent claims may be rendered obvious by combining the teachings of Japanese PCT Publication No. 2006-519549 (Patent Document 1) and Japanese Patent Laying-Open No. 2000-194346 (Patent Document 2), as acknowledged and described within the patent itself.

Independent Claims Overview

The independent claims of US12160681, specifically claims 1, 9, 11, and 19, center on a video transmitting apparatus and a method for controlling it. The core inventive concept involves:

• A video transmitting apparatus wirelessly communicating with a display.
• The apparatus transmitting a request message along with a "first number" to obtain capability information (e.g., EDID) from the display.
• Storing this capability information and determining audio/video stream parameters.
• Transmitting the audio/video stream.
• Crucially, under a "predetermined condition," transmitting a "second request message" with a "second number" that is different from the first number, where one is generated by increasing the other by an arbitrary number. This "number" (referred to as "history number" or "revision value" in the patent's detailed description) serves as a version indicator for the display's capability information.
• Claims 9 and 19 further elaborate on storing a "third number" and a "fourth number" from the display, implying a more sophisticated versioning system.

Prior Art References and Their Teachings

1. Patent Document 1 (Japanese PCT Publication No. 2006-519549):

   • Addresses the problem of quickly reading out EDID from a display by a video transmitter, especially in interfaces with transmission delays and limited capacity, such as wireless connections.
   • Describes a "master simulator" on the display side continuously polling for changes in a "slave" (i.e., EDID) and maintaining the current condition in a "shadow memory" on the source (transmitter) side. This allows the transmitter to read EDID directly from the shadow memory without detecting the wireless link, thereby speeding up the process.

2. Patent Document 2 (Japanese Patent Laying-Open No. 2000-194346):

   • Describes a system where, upon a change in EDID information, corresponding data in a rewritable memory is updated, and a "unique ID to a product" within that EDID information is also rewritten.
   • The updated EDID information is then transmitted to a personal computer (source) via a DDC communication function.

Obviousness Analysis and Motivation to Combine

A person having ordinary skill in the art (PHOSITA) at the time of the invention would have been motivated to combine the teachings of Patent Document 1 and Patent Document 2 to achieve the efficiency benefits claimed by US12160681.

Motivation for Combination:

Patent Document 1 highlights the problem of transmission delay and capacity limitations in wireless interfaces when reading EDID, and proposes a solution involving continuous polling for changes and maintaining a shadow memory on the transmitter side for quick access. However, continuous polling of the entire EDID, even for changes, could still be inefficient and consume precious wireless bandwidth.

Patent Document 2 provides a more granular mechanism for indicating EDID changes: by rewriting a "unique ID to a product" whenever the EDID content changes. A PHOSITA, seeking to improve the efficiency of the system described in Patent Document 1, would recognize that the "unique ID" from Patent Document 2 could serve as an efficient "checksum" or "version number" for the EDID data.

How the Combination Renders Claims Obvious:

1. Initial Connection and EDID Acquisition (Claims 1, 11): Both Patent Document 1 and 2 implicitly, or explicitly, deal with a video transmitter acquiring EDID from a display. The initial transmission of a request message with a "first number" (e.g., '0' as an initial revision value as described in US12160681's detailed description) and receiving the full EDID is a standard operation.
2. Efficient Change Detection via History Number (Claims 1, 11): Instead of the continuous polling of the entire EDID as might be inferred from Patent Document 1's "polling on change," a PHOSITA would be motivated to use the "unique ID to a product" concept from Patent Document 2.
   • The transmitter would send a request message containing its currently stored "unique ID" (acting as the "first number").
   • The display, upon receiving this request, would compare the received "unique ID" with its own internally stored and updated "unique ID" (which changes when EDID changes, as per Patent Document 2).
   • If the IDs are inconsistent (meaning the display's EDID has changed), the display would transmit its new EDID along with its updated "unique ID" (acting as the "second number"). If they are consistent, it could send a message indicating no change, avoiding full EDID transmission.
   • The mechanism of "increasing the other of the first number and the second number by an arbitrary number" is a well-known and conventional method for generating version or revision numbers in computing systems, and would be an obvious choice for a PHOSITA implementing the "unique ID" of Patent Document 2 as a revision counter.
3. Advanced History Tracking (Claims 9, 19): The storage of a "third number" and a "fourth number" from the display, where the fourth is generated from the third, is a natural extension of the versioning concept. If the "unique ID" of Patent Document 2 is the "third number," and the display "rewrites" it upon a change, this rewritten ID would become the "fourth number" (e.g., incremented version). This simply represents multiple iterations of the same change-detection and version-update process.

Therefore, a PHOSITA would find it obvious to combine the shadow memory and polling concept of Patent Document 1 with the specific EDID change signaling mechanism (using a unique, rewritable ID) of Patent Document 2. This combination would lead directly to the claimed invention's method of using a revision number to efficiently manage EDID updates over wireless interfaces, minimizing unnecessary data transmission and addressing the problems articulated in the background of US12160681.