Invention Grant
US08175525B2 Conversion from note-based audio format to PCM-based audio format
有权
从基于音频的音频格式转换为基于PCM的音频格式
- Patent Title: Conversion from note-based audio format to PCM-based audio format
- Patent Title (中): 从基于音频的音频格式转换为基于PCM的音频格式
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Application No.: US12943139Application Date: 2010-11-10
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Publication No.: US08175525B2Publication Date: 2012-05-08
- Inventor: Rodney Bylsma
- Applicant: Rodney Bylsma
- Applicant Address: CA Waterloo
- Assignee: Research In Motion Limited
- Current Assignee: Research In Motion Limited
- Current Assignee Address: CA Waterloo
- Agency: Novak Druce + Quigg LLP
- Main IPC: H04Q7/32
- IPC: H04Q7/32

Abstract:
A system and method for converting a note-based audio object to a Pulse Code Modulated (PCM) audio format is disclosed. An electronic computer device includes a memory containing a note-based audio object and a lookup table, the note-based audio object containing note frequency information. A processor is configured for converting the note-based audio object to a Pulse Code Modulated (PCM) stream having a plurality of sample points, the converting including: generating a PCM value for each sample point based upon the note frequency and the trigonometric function evaluations, selecting an entry from the look-up table based upon the note frequency information, a sampling frequency, and a sample point number, and determining a step size within the look-up table based upon a ratio between the note frequency information and the sampling frequency.
Public/Granted literature
- US20110053655A1 CONVERSION FROM NOTE-BASED AUDIO FORMAT TO PCM-BASED AUDIO FORMAT Public/Granted day:2011-03-03
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