An imaging apparatus is described for obtaining images. The imaging apparatus includes a pixel array, a row decoder, a column decoder, and a trigger circuit. The pixel array integrates electrical signals corresponding to incident light from a scene. The row decoder enables a selected row of pixels within the pixel array. The column decoder enables readout of a pixel in a selected column of the selected row within the pixel array. The trigger circuit generates one or more burst pulses to traverse through a corresponding number of decoder stages that correspond to pixels which are identified for discarding. Each burst pulse has a duration that is less than a stipulated minimum pulse duration of a typical decoder pulse of the decoders. By using shorter burst pulses, the trigger circuit can quickly jump to a desired row and/or column of pixels for readout, while conserving power.