Automatic electronic camera for label image capture

An electronic camera for producing a digital image over a range of light intensities;

• comprising:
• an image sensor assembly including an adjustable shutter speed control and means for generating an analog image signal, said image signal including a plurality of pixels;
• a video gain circuit configured to receive said analog image signal and to output an amplified analog image signal;
• an analog-to-digital converter including an A/D gain controller responsive to an A/D reference input and configured to convert said amplified analog image signal to a digital image signal;
• and
• an intensity evaluator circuit configured to receive said digital image signal and to output a correction signal varying with the intensity of at least a portion of said digital image signal;
• said shutter speed control, said video gain circuit, and said A/D reference input being responsive to said correction signal,
• said intensity evaluator circuit including
• a first memory including a plurality of bits, each of said plurality of bits corresponding to one of said plurality of pixels, said plurality of bits including a predetermined number of hit bits, said hit bits identifying a preselected subset of said plurality of pixels to be sampled to determine the intensity of said image;
• a second memory including a plurality of bins, each of said bins corresponding to one of a plurality of possible intensity levels associated with said preselected subset of said plurality of pixels,
• said correction signal being determined by
• determining, for each of said preselected subset of said plurality of pixels, the intensity of said pixel and incrementing the bin in said second memory corresponding to the intensity of said pixel;
• sequentially summing the values in said bins;
• determining when said sum exceeds a predetermined number;
• and
• defining a last bin value responsive to said sum exceeding said predetermined number.

An electronic camera system for producing an image including a plurality of pixels and evaluating the intensity of an image, comprising:

• a first memory including a plurality of bits, each bit corresponding to one of the pixels, the plurality of bits identifying a preselected subset of the pixels to be sampled to determine the intensity of the image;
• a second memory including a plurality of bins, each bin corresponding to one of a plurality of possible intensity levels associated with the preselected subset of the plurality of pixels;
• and
• means for computing an output indicative of the brightness of the image by
• for each pixel of the preselected subset, determining the intensity of the pixel and incrementing a bin value of a particular one of the bins in the second memory corresponding to the intensity of the pixel;
• beginning with the one of the bins corresponding to the lowest of the possible intensity levels, sequentially summing the bin values in increasing intensity level order to compute a bin-value sum;
• determining a last bin when the bin-value sum exceeds a predetermined portion of the sampled subset of the pixels;
• and
• assigning to the output a value corresponding to the intensity level associated with the last bin.