Adaptive Reference Frame Selection in Video Transcoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing transcoding technologies, such as Japanese Patent JP-A No. 23444/2004, fail to efficiently convert motion picture streams due to inadequate correlation between reference frames and encoded frames, leading to increased processing load and power consumption, especially when frames are intraframe-coded.
Innovation Solution
A transcoder that decodes a motion picture stream and detects whether frames are intraframe-coded or interframe-coded, adjusting the reference frame or search order accordingly to optimize encoding, using a decoder for MPEG2 and an encoder for H.264, reducing circuit scale and power consumption by excluding reference images with inadequate correlation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the reference frame is determined in accordance with the same relationship as an unconverted stream relationship, then the transcoding operation can be performed, but compression cannot be achieved with high efficiency because there is an inadequate correlation between the reference frame and the frame to be encoded when frames are intraframe-coded
Solution Approach 1:
The patent dynamically adjusts the reference frame determination method based on the frame type (intraframe or interframe). When intraframe-coded frames are detected, the system switches to a different reference frame selection strategy, making the reference frame determination adaptive rather than static, thereby improving compression efficiency without excessive complexity
Solution Approach 2:
The patent changes the parameter of reference frame selection based on the coding type parameter. By detecting whether frames are intraframe or interframe coded, the system modifies the reference frame determination parameter accordingly, optimizing compression efficiency for each frame type while maintaining manageable system complexity
2Device complexity
If two frames are sequentially searched for in accordance with the same relationship as an unconverted stream relationship, then the transcoding can be performed, but an extra process needs to be performed which is not suitable for circuit scale reduction and power consumption reduction
Solution Approach 1:
The patent extracts and eliminates unnecessary sequential frame searching processes by directly determining reference frames based on frame type detection. This removes redundant processing steps, reducing circuit scale and power consumption while maintaining adequate processing speed through smarter, more direct reference frame selection
3Use of energy by stationary object
If the reference frame is determined in accordance with the same relationship as an unconverted stream relationship in a situation where the frames are intraframe-coded, then the transcoding operation can proceed, but compression cannot be achieved with high efficiency leading to increased processing load and power consumption
Solution Approach 1:
The patent changes the operational parameters of the transcoding system based on frame type detection. When intraframe-coded frames are identified, the system adjusts the reference frame selection parameter to optimize compression efficiency, thereby reducing the processing load and power consumption required for effective compression
Data Source
AI summary
In a transcoder that decodes and encodes a motion picture stream, a highly compressed motion picture stream cannot be obtained if the same corresponding frame is referenced for coding purposes in a situation where an intraframe coding mode, in which an unconverted stream is not provided with vector information, is used and in a situation where an interframe predictive coding mode, in which the unconverted stream is provided with vector information, is used. Further, if an additional frame is referenced after searching for the corresponding frame, the circuit scale and power consumption increase. To solve the above problems, the disclosed transcoder comprises a decoder for decoding an input motion picture stream and detecting sub-information indicating whether an intraframe coding scheme or interframe predictive coding scheme is used; and an encoder for changing the frame to be referenced at the time of coding depending on whether the sub-information indicates the use of the intraframe coding scheme or interframe predictive coding scheme.