Solid-state image pickup device and method of operating the same

There is disclosed a solid-state image pickup device provided with plural blocks, each comprising at least two pixels 11 and allowing to read the signals of the pixel blocks at a high speed and without loss. The output signals of the blocks are connected in common, respectively through block buffers 83, thereby providing the maximum or minimum value of the pixels. The block buffer 83 has an input at the base of a self-biased transistor and an output in an emitter follower circuit. Also there are provided first photoelectric conversion elements for reading out the photoelectric conversion charges of respective pixels and second photoelectric conversion elements for reaching out the photoelectric conversion charges respectively in blocks, each composed of plural pixels, and the outputs of the second photoelectric conversion elements are connected in common to a common line through maximum output circuits.