af73d55eff
-added instructions on how to run the example (using \include to insert a section from qtbase/doc/global/) -updated copyright year -removed links to Qt 4 API -rearranged some of the sections -created links from the example pages to Qt Multimedia -fixed QDoc warnings related to the example pages Task-number: QTBUG-33597 Change-Id: Id45ce5cbd40dbfa384abd7260a316f6f6837c186 Reviewed-by: Yoann Lopes <yoann.lopes@digia.com> Reviewed-by: Sze Howe Koh <szehowe.koh@gmail.com>
65 lines
2.8 KiB
Plaintext
65 lines
2.8 KiB
Plaintext
/****************************************************************************
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**
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** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
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** Contact: http://www.qt-project.org/legal
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**
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** This file is part of the documentation of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:FDL$
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** Commercial License Usage
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** Licensees holding valid commercial Qt licenses may use this file in
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** accordance with the commercial license agreement provided with the
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** Software or, alternatively, in accordance with the terms contained in
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** a written agreement between you and Digia. For licensing terms and
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** conditions see http://qt.digia.com/licensing. For further information
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** use the contact form at http://qt.digia.com/contact-us.
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**
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** GNU Free Documentation License Usage
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** Alternatively, this file may be used under the terms of the GNU Free
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** Documentation License version 1.3 as published by the Free Software
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** Foundation and appearing in the file included in the packaging of
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** this file. Please review the following information to ensure
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** the GNU Free Documentation License version 1.3 requirements
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** will be met: http://www.gnu.org/copyleft/fdl.html.
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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/*!
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\example spectrum
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\title Spectrum Example
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\ingroup multimedia_examples
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\brief The Spectrum Example uses a combination multimedia APIs to process microphone input.
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The Spectrum Analyzer example shows how the \l{Qt Multimedia} module can be
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used to record and then play back an audio stream.
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\image spectrum-demo.png
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Because Qt Multimedia allows the application to access the raw audio
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stream, the data can either be inspected or modified by the application.
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The Spectrum Analyzer example displays three pieces of information while
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audio is being either captured or played back:
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\list
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\li Information about the raw audio stream, shown in the uppermost widget:
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\list
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\li The amount of data currently in the buffer, shown in blue
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\li The segment of data which was most recently analysed to compute
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the frequency spectrum, shown in green
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\li The raw audio waveform, shown in white and scrolling from right to
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left
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\endlist
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\li A representation of the frequency spectrum, shown at the lower left
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\li The current RMS level of the audio stream, and the recent 'high
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watermark' level, shown at the lower right
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\endlist
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Spectrum analysis is performed by calculating the Fast Fourier Transform
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(FFT) of a segment of audio data. An open-source library,
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\l{http://ldesoras.free.fr/prod.html}{FFTReal}, against which the
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application is dynamically linked, is used to compute the transform.
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\include examples-run.qdocinc
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*/
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