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    41 

    42 #include "waveform.h"

    43 #include "utils.h"

    44 #include <QPainter>

    45 #include <QResizeEvent>

    46 #include <QDebug>

    47 

    48 

    49 Waveform::Waveform(const QByteArray &buffer, QWidget *parent)

    50     :   QWidget(parent)

    51     ,   m_buffer(buffer)

    52     ,   m_dataLength(0)

    53     ,   m_position(0)

    54     ,   m_active(false)

    55     ,   m_tileLength(0)

    56     ,   m_tileArrayStart(0)

    57     ,   m_windowPosition(0)

    58     ,   m_windowLength(0)

    59 {

    60     setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);

    61     setMinimumHeight(50);

    62 }

    63 

    64 Waveform::~Waveform()

    65 {

    66     deletePixmaps();

    67 }

    68 

    69 void Waveform::paintEvent(QPaintEvent * /*event*/)

    70 {

    71     QPainter painter(this);

    72 

    73     painter.fillRect(rect(), Qt::black);

    74 

    75     if (m_active) {

    76         WAVEFORM_DEBUG << "Waveform::paintEvent"

    77                        << "windowPosition" << m_windowPosition

    78                        << "windowLength" << m_windowLength;

    79         qint64 pos = m_windowPosition;

    80         const qint64 windowEnd = m_windowPosition + m_windowLength;

    81         int destLeft = 0;

    82         int destRight = 0;

    83         while (pos < windowEnd) {

    84             const TilePoint point = tilePoint(pos);

    85             WAVEFORM_DEBUG << "Waveform::paintEvent" << "pos" << pos

    86                            << "tileIndex" << point.index

    87                            << "positionOffset" << point.positionOffset

    88                            << "pixelOffset" << point.pixelOffset;

    89 

    90             if (point.index != NullIndex) {

    91                 const Tile &tile = m_tiles[point.index];

    92                 if (tile.painted) {

    93                     const qint64 sectionLength = qMin((m_tileLength - point.positionOffset),

    94                                                      (windowEnd - pos));

    95                     Q_ASSERT(sectionLength > 0);

    96 

    97                     const int sourceRight = tilePixelOffset(point.positionOffset + sectionLength);

    98                     destRight = windowPixelOffset(pos - m_windowPosition + sectionLength);

    99 

   100                     QRect destRect = rect();

   101                     destRect.setLeft(destLeft);

   102                     destRect.setRight(destRight);

   103 

   104                     QRect sourceRect(QPoint(), m_pixmapSize);

   105                     sourceRect.setLeft(point.pixelOffset);

   106                     sourceRect.setRight(sourceRight);

   107 

   108                     WAVEFORM_DEBUG << "Waveform::paintEvent" << "tileIndex" << point.index

   109                                    << "source" << point.pixelOffset << sourceRight

   110                                    << "dest" << destLeft << destRight;

   111 

   112                     painter.drawPixmap(destRect, *tile.pixmap, sourceRect);

   113 

   114                     destLeft = destRight;

   115 

   116                     if (point.index < m_tiles.count()) {

   117                         pos = tilePosition(point.index + 1);

   118                         WAVEFORM_DEBUG << "Waveform::paintEvent" << "pos ->" << pos;

   119                     } else {

   120                         // Reached end of tile array

   121                         WAVEFORM_DEBUG << "Waveform::paintEvent" << "reached end of tile array";

   122                         break;

   123                     }

   124                 } else {

   125                     // Passed last tile which is painted

   126                     WAVEFORM_DEBUG << "Waveform::paintEvent" << "tile" << point.index << "not painted";

   127                     break;

   128                 }

   129             } else {

   130                 // pos is past end of tile array

   131                 WAVEFORM_DEBUG << "Waveform::paintEvent" << "pos" << pos << "past end of tile array";

   132                 break;

   133             }

   134         }

   135 

   136         WAVEFORM_DEBUG << "Waveform::paintEvent" << "final pos" << pos << "final x" << destRight;

   137     }

   138 }

   139 

   140 void Waveform::resizeEvent(QResizeEvent *event)

   141 {

   142     if (event->size() != event->oldSize())

   143         createPixmaps(event->size());

   144 }

   145 

   146 void Waveform::initialize(const QAudioFormat &format, qint64 audioBufferSize, qint64 windowDurationUs)

   147 {

   148     WAVEFORM_DEBUG << "Waveform::initialize"

   149                    << "audioBufferSize" << audioBufferSize

   150                    << "m_buffer.size()" << m_buffer.size()

   151                    << "windowDurationUs" << windowDurationUs;

   152 

   153     reset();

   154 

   155     m_format = format;

   156 

   157     // Calculate tile size

   158     m_tileLength = audioBufferSize;

   159 

   160     // Calculate window size

   161     m_windowLength = audioLength(m_format, windowDurationUs);

   162 

   163     // Calculate number of tiles required

   164     int nTiles;

   165     if (m_tileLength > m_windowLength) {

   166         nTiles = 2;

   167     } else {

   168         nTiles = m_windowLength / m_tileLength + 1;

   169         if (m_windowLength % m_tileLength)

   170             ++nTiles;

   171     }

   172 

   173     WAVEFORM_DEBUG << "Waveform::initialize"

   174                    << "tileLength" << m_tileLength

   175                    << "windowLength" << m_windowLength

   176                    << "nTiles" << nTiles;

   177 

   178     m_pixmaps.fill(0, nTiles);

   179     m_tiles.resize(nTiles);

   180 

   181     createPixmaps(rect().size());

   182 

   183     m_active = true;

   184 }

   185 

   186 void Waveform::reset()

   187 {

   188     WAVEFORM_DEBUG << "Waveform::reset";

   189 

   190     m_dataLength = 0;

   191     m_position = 0;

   192     m_format = QAudioFormat();

   193     m_active = false;

   194     deletePixmaps();

   195     m_tiles.clear();

   196     m_tileLength = 0;

   197     m_tileArrayStart = 0;

   198     m_windowPosition = 0;

   199     m_windowLength = 0;

   200 }

   201 

   202 void Waveform::dataLengthChanged(qint64 length)

   203 {

   204     WAVEFORM_DEBUG << "Waveform::dataLengthChanged" << length;

   205     const qint64 oldLength = m_dataLength;

   206     m_dataLength = length;

   207 

   208     if (m_active) {

   209         if (m_dataLength < oldLength)

   210             positionChanged(m_dataLength);

   211         else

   212             paintTiles();

   213     }

   214 }

   215 

   216 void Waveform::positionChanged(qint64 position)

   217 {

   218     WAVEFORM_DEBUG << "Waveform::positionChanged" << position;

   219 

   220     if (position + m_windowLength > m_dataLength)

   221         position = m_dataLength - m_windowLength;

   222 

   223     m_position = position;

   224 

   225     setWindowPosition(position);

   226 }

   227 

   228 void Waveform::deletePixmaps()

   229 {

   230     QPixmap *pixmap;

   231     foreach (pixmap, m_pixmaps)

   232         delete pixmap;

   233     m_pixmaps.clear();

   234 }

   235 

   236 void Waveform::createPixmaps(const QSize &widgetSize)

   237 {

   238     m_pixmapSize = widgetSize;

   239     m_pixmapSize.setWidth(qreal(widgetSize.width()) * m_tileLength / m_windowLength);

   240 

   241     WAVEFORM_DEBUG << "Waveform::createPixmaps"

   242                    << "widgetSize" << widgetSize

   243                    << "pixmapSize" << m_pixmapSize;

   244 

   245     Q_ASSERT(m_tiles.count() == m_pixmaps.count());

   246 

   247     // (Re)create pixmaps

   248     for (int i=0; i<m_pixmaps.size(); ++i) {

   249         delete m_pixmaps[i];

   250         m_pixmaps[i] = 0;

   251         m_pixmaps[i] = new QPixmap(m_pixmapSize);

   252     }

   253 

   254     // Update tile pixmap pointers, and mark for repainting

   255     for (int i=0; i<m_tiles.count(); ++i) {

   256         m_tiles[i].pixmap = m_pixmaps[i];

   257         m_tiles[i].painted = false;

   258     }

   259 

   260     paintTiles();

   261 }

   262 

   263 void Waveform::setWindowPosition(qint64 position)

   264 {

   265     WAVEFORM_DEBUG << "Waveform::setWindowPosition"

   266                    << "old" << m_windowPosition << "new" << position

   267                    << "tileArrayStart" << m_tileArrayStart;

   268 

   269     const qint64 oldPosition = m_windowPosition;

   270     m_windowPosition = position;

   271 

   272     if((m_windowPosition >= oldPosition) &&

   273         (m_windowPosition - m_tileArrayStart < (m_tiles.count() * m_tileLength))) {

   274         // Work out how many tiles need to be shuffled

   275         const qint64 offset = m_windowPosition - m_tileArrayStart;

   276         const int nTiles = offset / m_tileLength;

   277         shuffleTiles(nTiles);

   278     } else {

   279         resetTiles(m_windowPosition);

   280     }

   281 

   282     if(!paintTiles() && m_windowPosition != oldPosition)

   283         update();

   284 }

   285 

   286 qint64 Waveform::tilePosition(int index) const

   287 {

   288     return m_tileArrayStart + index * m_tileLength;

   289 }

   290 

   291 Waveform::TilePoint Waveform::tilePoint(qint64 position) const

   292 {

   293     TilePoint result;

   294     if (position >= m_tileArrayStart) {

   295         const qint64 tileArrayEnd = m_tileArrayStart + m_tiles.count() * m_tileLength;

   296         if (position < tileArrayEnd) {

   297             const qint64 offsetIntoTileArray = position - m_tileArrayStart;

   298             result.index = offsetIntoTileArray / m_tileLength;

   299             Q_ASSERT(result.index >= 0 && result.index <= m_tiles.count());

   300             result.positionOffset = offsetIntoTileArray % m_tileLength;

   301             result.pixelOffset = tilePixelOffset(result.positionOffset);

   302             Q_ASSERT(result.pixelOffset >= 0 && result.pixelOffset <= m_pixmapSize.width());

   303         }

   304     }

   305 

   306     return result;

   307 }

   308 

   309 int Waveform::tilePixelOffset(qint64 positionOffset) const

   310 {

   311     Q_ASSERT(positionOffset >= 0 && positionOffset <= m_tileLength);

   312     const int result = (qreal(positionOffset) / m_tileLength) * m_pixmapSize.width();

   313     return result;

   314 }

   315 

   316 int Waveform::windowPixelOffset(qint64 positionOffset) const

   317 {

   318     Q_ASSERT(positionOffset >= 0 && positionOffset <= m_windowLength);

   319     const int result = (qreal(positionOffset) / m_windowLength) * rect().width();

   320     return result;

   321 }

   322 

   323 bool Waveform::paintTiles()

   324 {

   325     WAVEFORM_DEBUG << "Waveform::paintTiles";

   326     bool updateRequired = false;

   327 

   328     for (int i=0; i<m_tiles.count(); ++i) {

   329         const Tile &tile = m_tiles[i];

   330         if (!tile.painted) {

   331             const qint64 tileEnd = m_tileArrayStart + (i + 1) * m_tileLength;

   332             if (m_dataLength >= tileEnd) {

   333                 paintTile(i);

   334                 updateRequired = true;

   335             }

   336         }

   337     }

   338 

   339     if (updateRequired)

   340         update();

   341 

   342     return updateRequired;

   343 }

   344 

   345 void Waveform::paintTile(int index)

   346 {

   347     WAVEFORM_DEBUG << "Waveform::paintTile" << "index" << index;

   348 

   349     const qint64 tileStart = m_tileArrayStart + index * m_tileLength;

   350     Q_ASSERT(m_dataLength >= tileStart + m_tileLength);

   351 

   352     Tile &tile = m_tiles[index];

   353     Q_ASSERT(!tile.painted);

   354 

   355     const qint16* base = reinterpret_cast<const qint16*>(m_buffer.constData());

   356     const qint16* buffer = base + (tileStart / 2);

   357     const int numSamples = m_tileLength / (2 * m_format.channels());

   358 

   359     QPainter painter(tile.pixmap);

   360 

   361     painter.fillRect(tile.pixmap->rect(), Qt::black);

   362 

   363     QPen pen(Qt::white);

   364     painter.setPen(pen);

   365 

   366     // Calculate initial PCM value

   367     qint16 previousPcmValue = 0;

   368     if (buffer > base)

   369         previousPcmValue = *(buffer - m_format.channels());

   370 

   371     // Calculate initial point

   372     const qreal previousRealValue = pcmToReal(previousPcmValue);

   373     const int originY = ((previousRealValue + 1.0) / 2) * m_pixmapSize.height();

   374     const QPoint origin(0, originY);

   375 

   376     QLine line(origin, origin);

   377 

   378     for (int i=0; i<numSamples; ++i) {

   379         const qint16* ptr = buffer + i * m_format.channels();

   380         const qint16 pcmValue = *ptr;

   381         const qreal realValue = pcmToReal(pcmValue);

   382 

   383         const int x = tilePixelOffset(i * 2 * m_format.channels());

   384         const int y = ((realValue + 1.0) / 2) * m_pixmapSize.height();

   385 

   386         line.setP2(QPoint(x, y));

   387         painter.drawLine(line);

   388         line.setP1(line.p2());

   389     }

   390 

   391     tile.painted = true;

   392 }

   393 

   394 void Waveform::shuffleTiles(int n)

   395 {

   396     WAVEFORM_DEBUG << "Waveform::shuffleTiles" << "n" << n;

   397 

   398     while (n--) {

   399         Tile tile = m_tiles.first();

   400         tile.painted = false;

   401         m_tiles.erase(m_tiles.begin());

   402         m_tiles += tile;

   403         m_tileArrayStart += m_tileLength;

   404     }

   405 

   406     WAVEFORM_DEBUG << "Waveform::shuffleTiles" << "tileArrayStart" << m_tileArrayStart;

   407 }

   408 

   409 void Waveform::resetTiles(qint64 newStartPos)

   410 {

   411     WAVEFORM_DEBUG << "Waveform::resetTiles" << "newStartPos" << newStartPos;

   412 

   413     QVector<Tile>::iterator i = m_tiles.begin();

   414     for ( ; i != m_tiles.end(); ++i)

   415         i->painted = false;

   416 

   417     m_tileArrayStart = newStartPos;

   418 }

   419