Fix bin clip thumbnails sometimes not created

src/bin/projectclip.cpp

@@ -501,7 +501,7 @@ QPixmap ProjectClip::thumbnail(int width, int height)
     return m_thumbnail.pixmap(width, height);
 }
 
-bool ProjectClip::setProducer(std::shared_ptr<Mlt::Producer> producer)
+bool ProjectClip::setProducer(std::shared_ptr<Mlt::Producer> producer, bool generateThumb)
 {
     qDebug() << "################### ProjectClip::setproducer";
     QMutexLocker locker(&m_producerMutex);
@@ -542,6 +542,10 @@ bool ProjectClip::setProducer(std::shared_ptr<Mlt::Producer> producer)
     getFileHash();
     // set parent again (some info need to be stored in producer)
     updateParent(parentItem().lock());
+    if (generateThumb && m_clipType != ClipType::Audio) {
+        // Generate video thumb
+        ClipLoadTask::start({ObjectType::BinClip,m_binId.toInt()}, QDomElement(), true, -1, -1, this);
+    }
     if (KdenliveSettings::audiothumbnails() && (m_clipType == ClipType::AV || m_clipType == ClipType::Audio || m_clipType == ClipType::Playlist || m_clipType == ClipType::Unknown)) {
         AudioLevelsTask::start({ObjectType::BinClip, m_binId.toInt()}, this, false);
     }

src/bin/projectclip.h

@@ -289,7 +289,7 @@ public slots:
      *  @param replaceProducer If true, we replace existing producer with this one
      *  @returns true if producer was changed
      * . */
-    bool setProducer(std::shared_ptr<Mlt::Producer> producer);
+    bool setProducer(std::shared_ptr<Mlt::Producer> producer, bool generateThumb = false);
     
     void importJsonMarkers(const QString &json);
     /** @brief Refresh zones of insertion in timeline. */

src/jobs/cliploadtask.cpp

@@ -225,7 +225,7 @@ void ClipLoadTask::generateThumbnail(std::shared_ptr<ProjectClip>binClip, std::s
     // Fetch thumbnail
     qDebug()<<"===== \nREADY FOR THUMB"<<binClip->clipType()<<"\n\n=========";
     int frameNumber = m_in > -1 ? m_in : qMax(0, binClip->getProducerIntProperty(QStringLiteral("kdenlive:thumbnailFrame")));
-    if (binClip->clipType() != ClipType::Audio && producer->get_int("video_index") > -1) {
+    if (producer->get_int("video_index") > -1) {
         if (ThumbnailCache::get()->hasThumbnail(QString::number(m_owner.second), frameNumber, false)) {
             // Thumbnail found in cache
             QImage result = ThumbnailCache::get()->getThumbnail(QString::number(m_owner.second), frameNumber);
@@ -659,13 +659,12 @@ void ClipLoadTask::run()
     if (!m_isCanceled) {
         auto binClip = pCore->projectItemModel()->getClipByBinID(QString::number(m_owner.second));
         if (binClip) {
-            QMetaObject::invokeMethod(binClip.get(), "setProducer", Qt::QueuedConnection, Q_ARG(std::shared_ptr<Mlt::Producer>,producer));
+            QMetaObject::invokeMethod(binClip.get(), "setProducer", Qt::QueuedConnection, Q_ARG(std::shared_ptr<Mlt::Producer>,producer), Q_ARG(bool,true));
             if (checkProfile && !isVariableFrameRate && seekable) {
                 pCore->bin()->shouldCheckProfile = false;
                 QMetaObject::invokeMethod(pCore->bin(), "slotCheckProfile", Qt::QueuedConnection, Q_ARG(QString, QString::number(m_owner.second)));
             }
         }
-        generateThumbnail(binClip, producer);
         emit taskDone();
     } else {
         // Might be aborted by profile switch

src/jobs/proxytask.cpp

@@ -37,7 +37,7 @@ void ProxyTask::start(const ObjectId &owner, QObject* object, bool force)
         task = nullptr;
     }
     if (task) {
-        // Otherwise, start a new audio levels generation thread.
+        // Otherwise, start a new proxy generation thread.
         task->m_isForce = force;
         pCore->taskManager.startTask(owner.second, task);
     }