In various embodiments, an image encoding application determines a first value for an encoding parameter based on a search interval. The image encoding application then encodes a source image using the first value for the encoding parameter to generate a first encoded image. Subsequently, the image encoding application computes a visual quality score for a first reconstructed source image derived from the first encoded image. The image encoding application reduces the search interval based on a comparison between the visual quality score and the target visual quality score. Based on the resulting reduced search interval, the image encoding application determines a second value for the encoding parameter. The image encoding application encodes the source image using the second value for the encoding parameter to generate a second encoded image. Subsequently, the image encoding application transmits the second encoded image to software application(s) for further processing and display.