How to get heatmap picture response from API DAHUA CAMERA?

[at.fajar]

I'm making an app that sends data from the DAHUA camera to a specific server. I need information from the camera heat map. In the API guide it is stated to access the URL as follows:

http://192.168.1.108/cgi-bin/heatMap.cgi?action=getPicByTime&channel=1&StartTime=2022-05-25%2000:00:00&EndTime=2022-05-30%2023:59:59

but the data I get is a HeatMap.CGI file. Whereas in the manual the response is
Content-Type: application/binarytet-stream
Content-Length: <heatMap size>
<HeatMap data>

Any one has implement Get Heat Map Information ?