PVQ Indexing With Leading Sign Split for 32-Bit DSPs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pyramid vector quantization (PVQ) indexing schemes are limited by their reliance on 32-bit integer ranges and cannot be efficiently implemented in digital signal processor (DSP) architectures that only support signed 32-bit integers, leading to increased complexity and overhead in indexing and de-indexing operations.
Innovation Solution
The proposed method iteratively decomposes PVQ structures and indices into leading sign sections, reducing the dynamic range required for indexing offsets and enabling the use of 33-bit PVQ indices in 32-bit DSP hardware, with marginal additional cost in terms of Million Operations Per Second (MOPS), Random Access Memory (RAM), and Program Read-Only Memory (P-ROM).
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If existing PVQ indexing schemes are used, then indexing operations can be performed, but they cannot be efficiently implemented in 32-bit DSP hardware that only supports signed 32-bit integers
Solution Approach 1:
The patent segments the 33-bit PVQ index into a sign bit and a 32-bit magnitude, allowing the magnitude to be processed using standard signed 32-bit integer arithmetic in DSP hardware. This segmentation enables efficient implementation by separating the sign handling from the magnitude computation, resolving the contradiction between hardware compatibility and indexing capability.
2Adaptability or versatility
If 33-bit PVQ indices are used to extend the index range, then more audio/video samples can be represented, but the complexity and overhead of indexing and de-indexing operations increases
Solution Approach 1:
The patent changes the parameter representation by using a sign-magnitude format where the index is represented as a signed 32-bit integer. This parameter change allows the system to achieve an extended effective index range while maintaining compatibility with standard 32-bit arithmetic operations, thereby reducing the complexity and overhead of indexing operations compared to implementing true 33-bit arithmetic.
Data Source
Figure 1~6
Figure 2
Figure 3
AI summary
A method for pyramid vector quantization indexing of audio/video signals comprises obtaining (402) of an integer input vector representing the audio/video signal samples. A leading sign is extracted(404) from the integer input vector. The leading sign is a sign of a terminal non-zero coefficient in the integer input vector. The terminal non-zero coefficient is one of a first non-zero coefficient and a last non-zero coefficient in the integer input vector. The integer input vector is indexed (406) with a pyramid vector quantization enumeration scheme into an output index representing the audio/video signal samples. The pyramid vector quantization enumeration scheme is designed for neglecting the sign of the terminal non-zero coefficient. The output index and the leading sign are outputted (408). A corresponding method for de-indexing, an encoder, a decoder, and computer programs therefore are also disclosed.