The invention describes an infrared imaging assembly (1) for capturing an infrared image (M0, M1) of a scene (S), comprising an infrared-sensitive image sensor (14); an irradiator (10) comprising an array of individually addressable infrared-emitting LEDs, wherein each infrared-emitting LED is arranged to illuminate a scene region (S1, . . . , S9); a driver (11) configured to actuate the infrared irradiator (10) by applying a switching pulse train (T1, . . . , T9) to each infrared-emitting LED; an image analysis module (13) configured to analyse a preliminary infrared image (M0) to determine the required exposure levels (130) for each of a plurality of image regions (R1, . . . , R9); and a pulse train adjusting unit (12) configured to adjust the duration (L1, . . . , L9) of a switching pulse train (T1, . . . , T9) according to the required exposure levels (130). The invention also described a method of generating a depth map (D) for a scene (S); a depth map generator comprising an embodiment of the inventive infrared imaging assembly (1); and a camera comprising such a depth map generator (2).