[论文笔记3]Aggregated channel features

We found that single-scale
 square Haar wavelets were sufficient in the ICF framework. Thus instead
 of computing integral images and Haar wavelets, we simply smooth and
 downsample the channels and the features are now single pixel lookups in
 the "aggregated" channels.

the aggregated pixels in all subsampled channels are then vectorized into a pixel look-up table.

由于特征直接从下采样的通道里由像素值提取而来，而不是使用积分图计算不同位置和比例的矩形区域求和。特征算的快，并且特征池变小。跟提升分类器配合好。

Feature design:

1.channel types:

color channel，gradient magnitude ,gradient histogram,

后两者可