/// <summary>
/// Uses the assigned value to a part to parameterize that part from examples.
/// It caches the parameterizations, and checks the cache to see if it has
/// made the parameterization beforeache.
/// </summary>
/// <param name="name">Name of the part to parameterize.</param>
/// <param name="value">The part's value.</param>
/// <param name="assignment">The whole assignment.</param>
/// <param name="positives">Positive examples</param>
/// <param name="negatives">Negative examples</param>
/// <param name="cache">The cache foreach storing parameterizations to check foreach subsequent calls.</param>
/// <returns>The parameterized part (either a feature or region)</returns>
public static object ExtractPart(string name, object value,
Dictionary <string, Part> assignment, IEnumerable <Bitmap> positives, IEnumerable <Bitmap> negatives, Dictionary <object, object> cache)
{
//Look in our cache to see if we extracted the part beforeache
object extracted = null;
Size size = null;
RegionParameters rps = null;
BackgroundValue bv = null;
if (value is Size)
{
size = (Size)value;
}
else if (value is RegionParameters)
{
rps = (RegionParameters)value;
}
else if (value is string)
{
bv = GetBackgroundValue((String)value, assignment);
value = bv;
}
Tuple <string, object> key = new Tuple <string, object>(name, value);
if (!cache.ContainsKey(key))
{
switch (name)
{
case "topleft":
extracted = CropFromManyRelativeTopLeft(0, 0, size.Width, size.Height, positives);
break;
case "bottomleft":
extracted = CropFromManyRelativeBottomLeft(size.Height, 0, size.Width, size.Height, positives);
break;
case "topright":
extracted = CropFromManyRelativeTopRight(0, size.Width, size.Width, size.Height, positives);
break;
case "bottomright":
extracted = CropFromManyRelativeBottomRight(size.Height, size.Width, size.Width, size.Height, positives);
break;
case "top":
extracted = GetHorizontal(true, rps.Start, rps.End, rps.Depth, positives);
break;
case "bottom":
extracted = GetHorizontal(false, rps.Start, rps.End, rps.Depth, positives);
break;
case "left":
extracted = GetVertical(true, rps.Start, rps.End, rps.Depth, positives);
break;
case "right":
extracted = GetVertical(false, rps.Start, rps.End, rps.Depth, positives);
break;
case "interior":
extracted = GetInterior(bv, positives);
break;
}
//Features that have all one value are likely to be background. So we disallow it.
//Features that are all transparent can't be found (obviously). So we disallow it.
if (extracted != null && extracted is Bitmap && (Bitmap.AllOneValue((Bitmap)extracted) || Bitmap.AllTransparent((Bitmap)extracted)))
{
extracted = null;
}
cache.Add(key, extracted);
}
else
{
extracted = cache[key];
}
return(extracted);
}
