private SampleCollection CreateNextSamples(SampleCollection allNegSamples, double falsePositiveRate, int maxSampleNum)
{
int selectSampleCount = (int)(maxSampleNum / falsePositiveRate);
if (selectSampleCount <= 0)
{
selectSampleCount = allNegSamples.Count;
}
SampleCollection negSamples = allNegSamples.GetNegSamples(selectSampleCount);
int oldNum = negSamples.Count;
negSamples = this.GetPositivePredictedSamples(negSamples);
if (DebugMsg.Debug)
{
string msg = string.Format("选取了{0}个负样本，通过了{1}个，误检率为{2:P5}\r\n",
oldNum, negSamples.Count, (MyFloat)negSamples.Count / oldNum);
DebugMsg.AddMessage(msg, 0);
}
if (negSamples.Count > maxSampleNum)
{
negSamples.TrimExcess(maxSampleNum);
}
GC.Collect();
return(negSamples);
}
/// <summary>
/// 使用当前的级联分类器对负目标negSamples进行分类，返回错分的目标，作为新的负样本集negSamples
/// </summary>
/// <param name="negSamples"></param>
/// <returns></returns>
private SampleCollection GetPositivePredictedSamples(SampleCollection samplecoll)
{
SampleCollection newCollection = new SampleCollection(samplecoll.Count);
foreach (ISample sample in samplecoll)
{
if (true == this.Predict(sample))
{
newCollection.Add(sample);
}
}
newCollection.TrimExcess();
return(newCollection);
}