Variable Frame Rate Buffer Control to Prevent Frame Tearing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional frame rate control methods result in decreased refresh rate and frame tearing when dealing with variable frame rates due to mismatched input and output rates, leading to poor video quality.
Innovation Solution
A method and system for controlling the timing of write and read operations to access buffer blocks, using a frame rate controller, buffer-reading clock, and write-mask clock to synchronize write and read actions with progress thresholds, preventing overwriting and ensuring data integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single buffer block is used for frame-by-frame storage, then the device complexity is reduced, but frame tearing and refresh rate decrease occur under variable frame rates
Solution Approach 1:
The patent implements dynamic buffer block management where multiple buffer blocks are selectively activated based on frame rate conditions. The system transitions between single-buffer mode (for fixed frame rates) and multi-buffer mode (for variable frame rates), dynamically adjusting the buffer configuration to match operational requirements and prevent frame tearing.
Solution Approach 2:
The system changes the operational parameters of the buffer system by introducing a progress threshold parameter that controls when buffer blocks are switched. By monitoring the writing progress and comparing it against the threshold, the system dynamically adjusts buffer usage to maintain video quality under variable frame rates while managing complexity.
2Productivity
If the write end continuously writes frame images to the buffer, then the productivity is improved, but frame tearing occurs when the read end cannot keep up
Solution Approach 1:
The patent implements a feedback mechanism where the writing end continuously monitors the reading progress of the buffer. When the writing progress approaches the progress threshold or detects that the read end cannot keep up, the system provides feedback to pause or slow down the writing operation, preventing frame tearing while maintaining high productivity during normal operation.
Solution Approach 2:
The system performs preliminary actions by pre-configuring multiple buffer blocks and establishing progress thresholds before variable frame rate conditions occur. This preparation allows the system to quickly switch to a protective mode (pausing writes) when frame tearing risks are detected, maintaining both productivity and frame integrity.
3Reliability
If the read end waits for the write end to complete writing, then frame tearing is prevented, but the refresh rate decreases
Solution Approach 1:
The patent segments the buffer into multiple buffer blocks that can be independently managed. Instead of having the read end wait for complete writing of a single buffer, the system allows reading to proceed from one buffer block while writing occurs in another, enabling parallel operations that maintain refresh rate while preventing frame tearing through proper synchronization at block boundaries.
Data Source
AI summary
A method for reading and writing frame images having variable frame rates and a system therefor are provided. The system provides a video processing system that includes a write end and a read end for accessing a single buffer block. In the method performed in the video processing system, when the read end starts to read an image frame, the read end is controlled to not read data from the buffer block until the data written by the write end to the buffer block reaches a progress threshold; and when it is determined that a portion of the data in the buffer block not yet read by the read end will be overwritten by the data written by the write end, the writing process is terminated until the read end finishes reading the data in the portion in the buffer block.