Data Sets
Crowd Counting Data Set (UCF-CC-50)
This data set contains images of extremely dense crowds. The images are collected mainly from the FLICKR. They are shared only for the research purposes. Please consult the terms and conditions to use these images from FLICKR. Some of the images are shown below:

The data set can be downloaded by clicking here.
If you happen to use the data set, please refer to the following paper:
Haroon Idrees, Imran Saleemi, Cody Seibert, Mubarak Shah, Multi-Source Multi-Scale Counting in Extremely Dense Crowd Images, IEEE International Conference on Computer Vision and Pattern Recognition (CVPR), 2013.