<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>wavfile.cpp Example File | Qt Multimedia 5.12.6</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtmultimedia-index.html">Qt Multimedia</a></td><td ><a href="qtmultimedia-multimedia-spectrum-example.html">Spectrum Example</a></td><td >wavfile.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtmultimedia-index.html">Qt 5.12.6 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"><div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">wavfile.cpp Example File</h1> <span class="subtitle">multimedia/spectrum/app/wavfile.cpp</span> <!-- $$$multimedia/spectrum/app/wavfile.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2017 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include <qendian.h></span> <span class="preprocessor">#include "wavfile.h"</span> <span class="keyword">struct</span> chunk { <span class="type">char</span> id<span class="operator">[</span><span class="number">4</span><span class="operator">]</span>; <span class="type">quint32</span> size; }; <span class="keyword">struct</span> RIFFHeader { chunk descriptor; <span class="comment">// "RIFF"</span> <span class="type">char</span> type<span class="operator">[</span><span class="number">4</span><span class="operator">]</span>; <span class="comment">// "WAVE"</span> }; <span class="keyword">struct</span> WAVEHeader { chunk descriptor; <span class="type">quint16</span> audioFormat; <span class="type">quint16</span> numChannels; <span class="type">quint32</span> sampleRate; <span class="type">quint32</span> byteRate; <span class="type">quint16</span> blockAlign; <span class="type">quint16</span> bitsPerSample; }; <span class="keyword">struct</span> DATAHeader { chunk descriptor; }; <span class="keyword">struct</span> CombinedHeader { RIFFHeader riff; WAVEHeader wave; }; WavFile<span class="operator">::</span>WavFile(<span class="type">QObject</span> <span class="operator">*</span>parent) : <span class="type">QFile</span>(parent) <span class="operator">,</span> m_headerLength(<span class="number">0</span>) { } bool WavFile<span class="operator">::</span>open(<span class="keyword">const</span> <span class="type">QString</span> <span class="operator">&</span>fileName) { close(); setFileName(fileName); <span class="keyword">return</span> <span class="type">QFile</span><span class="operator">::</span>open(<span class="type">QIODevice</span><span class="operator">::</span>ReadOnly) <span class="operator">&</span><span class="operator">&</span> readHeader(); } <span class="keyword">const</span> <span class="type"><a href="qaudioformat.html">QAudioFormat</a></span> <span class="operator">&</span>WavFile<span class="operator">::</span>fileFormat() <span class="keyword">const</span> { <span class="keyword">return</span> m_fileFormat; } <span class="type">qint64</span> WavFile<span class="operator">::</span>headerLength() <span class="keyword">const</span> { <span class="keyword">return</span> m_headerLength; } bool WavFile<span class="operator">::</span>readHeader() { seek(<span class="number">0</span>); CombinedHeader header; bool result <span class="operator">=</span> read(<span class="keyword">reinterpret_cast</span><span class="operator"><</span><span class="type">char</span> <span class="operator">*</span><span class="operator">></span>(<span class="operator">&</span>header)<span class="operator">,</span> <span class="keyword">sizeof</span>(CombinedHeader)) <span class="operator">=</span><span class="operator">=</span> <span class="keyword">sizeof</span>(CombinedHeader); <span class="keyword">if</span> (result) { <span class="keyword">if</span> ((memcmp(<span class="operator">&</span>header<span class="operator">.</span>riff<span class="operator">.</span>descriptor<span class="operator">.</span>id<span class="operator">,</span> <span class="string">"RIFF"</span><span class="operator">,</span> <span class="number">4</span>) <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span> <span class="operator">|</span><span class="operator">|</span> memcmp(<span class="operator">&</span>header<span class="operator">.</span>riff<span class="operator">.</span>descriptor<span class="operator">.</span>id<span class="operator">,</span> <span class="string">"RIFX"</span><span class="operator">,</span> <span class="number">4</span>) <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) <span class="operator">&</span><span class="operator">&</span> memcmp(<span class="operator">&</span>header<span class="operator">.</span>riff<span class="operator">.</span>type<span class="operator">,</span> <span class="string">"WAVE"</span><span class="operator">,</span> <span class="number">4</span>) <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> memcmp(<span class="operator">&</span>header<span class="operator">.</span>wave<span class="operator">.</span>descriptor<span class="operator">.</span>id<span class="operator">,</span> <span class="string">"fmt "</span><span class="operator">,</span> <span class="number">4</span>) <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> (header<span class="operator">.</span>wave<span class="operator">.</span>audioFormat <span class="operator">=</span><span class="operator">=</span> <span class="number">1</span> <span class="operator">|</span><span class="operator">|</span> header<span class="operator">.</span>wave<span class="operator">.</span>audioFormat <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>)) { <span class="comment">// Read off remaining header information</span> DATAHeader dataHeader; <span class="keyword">if</span> (qFromLittleEndian<span class="operator"><</span><span class="type">quint32</span><span class="operator">></span>(header<span class="operator">.</span>wave<span class="operator">.</span>descriptor<span class="operator">.</span>size) <span class="operator">></span> <span class="keyword">sizeof</span>(WAVEHeader)) { <span class="comment">// Extended data available</span> <span class="type">quint16</span> extraFormatBytes; <span class="keyword">if</span> (peek((<span class="type">char</span><span class="operator">*</span>)<span class="operator">&</span>extraFormatBytes<span class="operator">,</span> <span class="keyword">sizeof</span>(<span class="type">quint16</span>)) <span class="operator">!</span><span class="operator">=</span> <span class="keyword">sizeof</span>(<span class="type">quint16</span>)) <span class="keyword">return</span> <span class="keyword">false</span>; <span class="keyword">const</span> <span class="type">qint64</span> throwAwayBytes <span class="operator">=</span> <span class="keyword">sizeof</span>(<span class="type">quint16</span>) <span class="operator">+</span> qFromLittleEndian<span class="operator"><</span><span class="type">quint16</span><span class="operator">></span>(extraFormatBytes); <span class="keyword">if</span> (read(throwAwayBytes)<span class="operator">.</span>size() <span class="operator">!</span><span class="operator">=</span> throwAwayBytes) <span class="keyword">return</span> <span class="keyword">false</span>; } <span class="keyword">if</span> (read((<span class="type">char</span><span class="operator">*</span>)<span class="operator">&</span>dataHeader<span class="operator">,</span> <span class="keyword">sizeof</span>(DATAHeader)) <span class="operator">!</span><span class="operator">=</span> <span class="keyword">sizeof</span>(DATAHeader)) <span class="keyword">return</span> <span class="keyword">false</span>; <span class="comment">// Establish format</span> <span class="keyword">if</span> (memcmp(<span class="operator">&</span>header<span class="operator">.</span>riff<span class="operator">.</span>descriptor<span class="operator">.</span>id<span class="operator">,</span> <span class="string">"RIFF"</span><span class="operator">,</span> <span class="number">4</span>) <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) m_fileFormat<span class="operator">.</span>setByteOrder(<span class="type"><a href="qaudioformat.html">QAudioFormat</a></span><span class="operator">::</span>LittleEndian); <span class="keyword">else</span> m_fileFormat<span class="operator">.</span>setByteOrder(<span class="type"><a href="qaudioformat.html">QAudioFormat</a></span><span class="operator">::</span>BigEndian); <span class="type">int</span> bps <span class="operator">=</span> qFromLittleEndian<span class="operator"><</span><span class="type">quint16</span><span class="operator">></span>(header<span class="operator">.</span>wave<span class="operator">.</span>bitsPerSample); m_fileFormat<span class="operator">.</span>setChannelCount(qFromLittleEndian<span class="operator"><</span><span class="type">quint16</span><span class="operator">></span>(header<span class="operator">.</span>wave<span class="operator">.</span>numChannels)); m_fileFormat<span class="operator">.</span>setCodec(<span class="string">"audio/pcm"</span>); m_fileFormat<span class="operator">.</span>setSampleRate(qFromLittleEndian<span class="operator"><</span><span class="type">quint32</span><span class="operator">></span>(header<span class="operator">.</span>wave<span class="operator">.</span>sampleRate)); m_fileFormat<span class="operator">.</span>setSampleSize(qFromLittleEndian<span class="operator"><</span><span class="type">quint16</span><span class="operator">></span>(header<span class="operator">.</span>wave<span class="operator">.</span>bitsPerSample)); m_fileFormat<span class="operator">.</span>setSampleType(bps <span class="operator">=</span><span class="operator">=</span> <span class="number">8</span> <span class="operator">?</span> <span class="type"><a href="qaudioformat.html">QAudioFormat</a></span><span class="operator">::</span>UnSignedInt : <span class="type"><a href="qaudioformat.html">QAudioFormat</a></span><span class="operator">::</span>SignedInt); } <span class="keyword">else</span> { result <span class="operator">=</span> <span class="keyword">false</span>; } } m_headerLength <span class="operator">=</span> pos(); <span class="keyword">return</span> result; } </pre> </div> <!-- @@@multimedia/spectrum/app/wavfile.cpp --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>