public LoadSequence(CryptoRandom random, int nCount, int nImageCount, RefreshManager refresh)
{
// When using load limit (count < image count), load item indexes in such
// a way that balances the number of items per label.
if (nCount < nImageCount)
{
Dictionary <int, List <DbItem> > rgItemsByLabel = refresh.GetItemsByLabel();
List <int> rgLabel = rgItemsByLabel.Where(p => p.Value.Count > 0).Select(p => p.Key).ToList();
for (int i = 0; i < nCount; i++)
{
int nLabelIdx = random.Next(rgLabel.Count);
int nLabel = rgLabel[nLabelIdx];
List <DbItem> rgItems = rgItemsByLabel[nLabel];
int nItemIdx = random.Next(rgItems.Count);
DbItem item = rgItems[nItemIdx];
m_rgLoadSequence.Add(item.Index);
rgLabel.Remove(nLabel);
if (rgLabel.Count == 0)
{
rgLabel = rgItemsByLabel.Where(p => p.Value.Count > 0).Select(p => p.Key).ToList();
}
}
refresh.Reset();
}
// Otherwise just load all item indexes.
else
{
for (int i = 0; i < nCount; i++)
{
m_rgLoadSequence.Add(i);
}
}
}
/// <summary>
/// The dataLoadThread is responsible for loading the data source images in the background.
/// </summary>
private void dataLoadThread()
{
m_evtRunning.Set();
DatasetFactory factory = new DatasetFactory(m_factory);
int? nNextIdx = m_loadSequence.GetNext();
Stopwatch sw = new Stopwatch();
if (m_refreshManager != null)
{
m_refreshManager.Reset();
}
try
{
sw.Start();
List <int> rgIdxBatch = new List <int>();
int nBatchSize = getBatchSize(m_src);
if (m_nLoadedCount > 0)
{
throw new Exception("The loaded count is > 0!");
}
factory.Open(m_src);
m_log.WriteLine(m_src.Name + " loading " + m_loadSequence.Count.ToString("N0") + " items...");
while (nNextIdx.HasValue || rgIdxBatch.Count > 0)
{
if (nNextIdx.HasValue)
{
rgIdxBatch.Add(nNextIdx.Value);
}
if (rgIdxBatch.Count >= nBatchSize || !nNextIdx.HasValue)
{
List <RawImage> rgImg;
if (m_refreshManager == null)
{
rgImg = factory.GetRawImagesAt(rgIdxBatch[0], rgIdxBatch.Count);
}
else
{
rgImg = factory.GetRawImagesAt(rgIdxBatch, m_evtCancel);
}
if (rgImg == null)
{
break;
}
for (int j = 0; j < rgImg.Count; j++)
{
SimpleDatum sd = factory.LoadDatum(rgImg[j]);
if (m_refreshManager != null)
{
m_refreshManager.AddLoaded(sd);
}
m_rgImages[m_nLoadedCount] = sd;
m_nLoadedCount++;
if (sw.Elapsed.TotalMilliseconds > 1000)
{
if (m_log != null && !m_bSilent)
{
double dfPct = m_nLoadedCount / (double)m_rgImages.Length;
m_log.Progress = dfPct;
m_log.WriteLine("Loading '" + m_src.Name + "' at " + dfPct.ToString("P") + " (" + m_nLoadedCount.ToString("N0") + " of " + m_rgImages.Length.ToString("N0") + ")...");
}
int nWait = WaitHandle.WaitAny(m_rgAbort.ToArray(), 0);
if (nWait != WaitHandle.WaitTimeout)
{
return;
}
sw.Restart();
}
}
rgIdxBatch = new List <int>();
}
nNextIdx = m_loadSequence.GetNext();
}
if (rgIdxBatch.Count > 0)
{
m_log.FAIL("Not all images were loaded!");
}
}
finally
{
factory.Close();
factory.Dispose();
m_evtRunning.Reset();
m_evtDone.Set();
}
}
