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Integer DCT based on direct-lifting of DCT-IDCT for lossless-to-lossy image coding
Summary
This study introduces a hardware-friendly integer Discrete Cosine Transform (IntDCT) for efficient image coding. This new IntDCT method is compatible with existing devices, simplifying lossless-to-lossy image compression.
Area of Science:
- Digital Signal Processing
- Image Compression Technologies
Background:
- Discrete Cosine Transform (DCT) is fundamental for JPEG/MPEG but standard implementations are not optimized for integer-based lossless-to-lossy coding.
- Existing integer DCT (IntDCT) methods often necessitate redesigned hardware, limiting their practical adoption.
Purpose of the Study:
- To propose a novel hardware-friendly integer DCT (IntDCT) suitable for both lossless and lossy image coding applications.
- To enable the use of IntDCT without requiring modifications to existing DCT hardware.
Main Methods:
- The proposed IntDCT is implemented using a direct-lifting approach applied to the standard DCT and inverse DCT (IDCT).
- This lifting technique allows seamless integration with existing DCT hardware components.
Main Results:
- The direct-lifting IntDCT is compatible with existing DCT devices, allowing them to be utilized for every lifting block.
- The method was validated through its successful application in lossless-to-lossy image coding scenarios.
Conclusions:
- The developed hardware-friendly IntDCT offers a practical solution for advanced image compression.
- This approach facilitates the transition to integer-based transforms without significant hardware redesign, improving efficiency and flexibility.
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