Composite Video Signaling for Mixed-Clock BT656/BT1120 Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing digital video signal transmission protocols, such as BT656 and BT1120, cannot simultaneously transmit video signals with different clock frequencies, limiting the flexibility of video signal transmission.
Innovation Solution
A method and apparatus for compositing video signals by adjusting the byte size of multiple video signals to match a target byte size within a unit time duration, allowing for composite modulation and transmission through a single interface, such as a BT656 or BT1120 interface, using a predetermined clock frequency, and subsequently stripping the composite signal to restore the original video signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If digital video signal transmission protocols (BT656, BT1120) are used to transmit video signals, then data transmission in YCbCr format is achieved, but video signals with different clock frequencies cannot be transmitted simultaneously
Solution Approach 1:
The patent segments the video signal transmission by introducing separate transmission paths for different clock frequencies. The composite video signal is divided into multiple independent data streams, each carrying video signals with specific clock frequencies (e.g., 25fps, 30fps, 50fps, 60fps), allowing simultaneous transmission without interference.
Solution Approach 2:
The patent implements dynamic clock frequency selection and signal routing. The system can dynamically switch between different clock frequencies and select appropriate video signals based on the desired frame rate, enabling flexible adaptation to different transmission requirements while maintaining protocol compatibility.
2Productivity
If byte size adjustment is performed on video signals to match target byte size, then composite modulation becomes possible, but processing complexity increases
Solution Approach 1:
The patent changes the byte size parameter of video signals to match a target byte size (e.g., 148.5MHz clock frequency corresponding to specific byte rate). By adjusting the byte size of different video formats (1080P, 720P, WD1-NTSC/PAL) to a common target, the system enables composite modulation while maintaining data integrity through standardized parameter alignment.
3Adaptability or versatility
If multiple video signals with different clock frequencies are composited, then transmission flexibility improves, but signal separation and recovery become more difficult
Solution Approach 1:
The patent introduces clock frequency identification information as an intermediary element in the composite video signal. This identification data, embedded within the signal stream, serves as a marker that enables the receiving end to automatically detect and separate different video signals based on their clock frequencies without complex external equipment.
Solution Approach 2:
The system implements feedback mechanisms where the receiving end detects the clock frequency identification information, determines the appropriate separation strategy, and recovers the original video signals accordingly. This closed-loop approach ensures accurate signal separation and recovery based on the transmitted identification data.
Data Source
AI summary
A method of compositing video signals includes: obtaining at least two video signals to be composited; determining a multiplier point mode corresponding to each of the at least two video signals; performing a byte size adjustment on the at least two video signals respectively according to the multiplier point mode corresponding to each of the at least two video signals; performing a composite modulation on bytes corresponding to the at least two video signals after the byte size adjustment, and outputting composite-modulated data through a target signal interface of an analog-to-digital conversion chip.