Video Variable-Speed Playback Timestamp Correlation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing video editing technologies face challenges in accurately correlating constant-speed presentation timestamps with variable-speed presentation timestamps after curve variable-speed editing, leading to poor user experience during video playback.
Innovation Solution
A method and apparatus for video variable-speed playback that involves acquiring constant-speed presentation timestamps and variable-speed playback speeds of designated video frames, converting these timestamps, establishing a speed variation curve, fitting it into straight line segments, and determining variable-speed presentation timestamps based on these segments to enable accurate playback starting from any video frame.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If curve variable-speed editing is applied to video frames, then video playback speed can be varied smoothly, but accurate correlation between constant-speed and variable-speed presentation timestamps becomes difficult to maintain
Solution Approach 1:
The patent divides the speed variation curve into multiple straight line segments, where each segment connects two adjacent control points. This segmentation transforms the complex curve into manageable linear sections, enabling precise timestamp calculations for each segment while maintaining overall smooth variable-speed playback. The segmentation principle resolves the contradiction by making the timestamp correlation tractable through piecewise linear approximation.
Solution Approach 2:
The patent changes the parameter representation from direct curve equations to a piecewise linear model with control points. By representing the speed variation as a series of linear segments defined by control points (timestamp, speed pairs), the system achieves both smooth playback (through continuous curve fitting) and accurate timestamp correlation (through linear interpolation within segments).
2Measurement precision
If a complex speed variation curve is used for precise timestamp correlation, then playback accuracy improves, but calculation complexity and processing time increase
Solution Approach 1:
The patent segments the speed variation curve into multiple straight line segments connecting control points. This segmentation reduces calculation complexity by replacing complex curve fitting with simple linear interpolation within each segment, while maintaining precision through sufficient segmentation density. The linear segments are computationally tractable yet collectively represent the smooth variable-speed profile.
Solution Approach 2:
The patent performs preliminary action by pre-establishing the speed variation curve and control points during video editing, before actual playback. This preprocessing creates a ready-to-use piecewise linear model that enables fast timestamp calculations during playback without real-time complex computations, resolving the contradiction between precision and computational complexity.
3Ease of operation
If variable-speed playback is implemented without accurate timestamp correlation, then playback can start from any frame, but user experience deteriorates due to timing inaccuracies
Solution Approach 1:
The patent performs preliminary action by pre-calculating and storing the piecewise linear speed variation curve with control points during editing. This preprocessing enables fast, accurate timestamp correlation during playback without real-time computation, allowing the system to quickly determine variable-speed timestamps for any frame while maintaining high precision through the established linear model.
Solution Approach 2:
The patent creates a copied representation of the speed variation relationship through the piecewise linear model with control points. This copied model (separate from the original video data) enables independent timestamp calculations for any frame without affecting the original video, providing both playback flexibility and timing accuracy through the decoupled computational model.
Data Source
AI summary
The present disclosure provides a video variable-speed playback method, an apparatus, an electronic device and a computer readable medium, and relates to the field of computer technology. The method includes: in response to a curve variable-speed instruction, acquiring constant-speed presentation timestamps and variable-speed playback speeds of first designated video frames in a video; converting the constant-speed presentation timestamps of the first designated video frames into variable-speed presentation timestamps; establishing a speed variation curve; fitting the speed variation curve into one or more straight line segments; based on a second designated video frame indicated by a variable-speed playback instruction, determining a corresponding constant-speed presentation timestamp; and determining a corresponding variable-speed presentation timestamp, and starting from the variable-speed presentation timestamp, playing the video at a variable-speed. The present disclosure can realize video variable-speed playback from any video frame during preview.