Method and apparatus for reading bar codes with a television camera

Claim 3

The method according to claim 1 wherein the image information associated with said one scan line is conditioned by first amplifying said information and thereafter thresholding it.

Claim 4

The method according to claim 1 further including the steps of: detecting the occurrence of every scan line in each frame; determining, from the occurrence of every scan line, the occurrence of said one scan line; enabling said FIFO storage device to be clocked at said first rate for the duration of said one scan line so that the binary signal indicative of the image information associated with said one scan line is written in said FIFO storage device.

Claim 5

The method according to claim 1 further including the step of conditioning the binary signal read from said FIFO storage device prior to decoding.

Claim 6

The method according to claim 4 wherein said conditioning step includes the step of modifying said binary signal to cause the signal to reflect a low contrast (space) portion in the binary code so that said space portion follows each high contrast (bar) portion.

Claim 7

The method according to claim 1 wherein the binary signal is only stored if the signal is indicative of a bar code.

Claim 8

Apparatus for reading a bar code on an object at a distance therefrom, comprising: a television camera for imaging the bar code on the object at a distance and for generating a video signal comprised of a plurality of frames, each frame including a plurality of scan lines, each scan line having image information associated therewith corresponding to the image of a strip across the bar code; a first signal conditioner coupled to the television camera for conditioning the image information associated with at least one predetermined scan line to yield a binary signal indicative of said image information; a First-In, First-Out storage device coupled to the first signal conditioner for storing the binary signal produced by the first signal conditioner; clock means coupled to the television camera and to the FIFO storage device for clocking the FIFO storage device at a first clock rate during the duration of said one predetermined scan line so that the binary signal indicative of the image information associated with said one predetermined scan line can be stored in the FIFO device and for clocking the FIFO storage device at a second rate, slower than said first rate, after said binary signal has been written into the FIFO storage device, to enable said binary signal to be read therefrom; and a bar code decoder coupled to the FIFO storage device means for decoding the binary signal read from the FIFO storage device.

Claim 9

Apparatus for reading a bar code on an object at a distance therefrom, comprising: a television camera for imaging the bar code on the object at a distance and for generating a video signal comprised of a plurality of frames, each frame including a plurality of scan lines, each scan line having image information associated therewith corresponding to the image of a strip across the bar code; a first signal conditioner coupled to the television camera for conditioning the image information associated with at least one predetermined scan line to yield a binary signal indicative of said image information; a First-In, First-Out storage device coupled to the first signal conditioner for storing the binary signal produced by the first signal conditioner; clock means coupled to the television camera and to the FIFO storage device for clocking the FIFO storage device at a first clock rate during the duration of said one predetermined scan line so that the binary signal indicative of the image information associated with said one predetermined scan line can be stored in the FIFO device and for clocking the FIFO storage device at a second rate, slower than said first rate, after said binary signal has been written into the FIFO storage device, to enable said binary signal to be read therefrom; and a bar code decoder coupled to the FIFO storage device means for decoding the binary signal read from the FIFO storage device.

Claim 10

The apparatus according to claim 7 wherein the bar code decoder means comprises: a second signal conditioner for conditioning the binary signal read from the FIFO storage device; a bar code decoder coupled to the second signal conditioner for decoding the signal conditioned by the second signal conditioner.

Claim 11

The apparatus according to claim 7 wherein the clock means comprises: a line synch detector coupled to the television camera and responsive to a camera output signal for indicating the duration of each scan line in each frame; a clock arbitrator coupled to the line synch detector and responsive to the indication provided thereby as to the duration of each scan line for determining the duration of said one predetermined scan line; and gate means coupled to said clock arbitrator and controlled thereby to clock the FIFO storage device at the first clock rate during the duration of said one predetermined scan line and for clocking the FIFO storage device at the second rate once said binary signal has been completely written therein.

Claim 12

The apparatus according to claim 7 further including means for verifying that the binary signal produced by said first signal conditioner is representative of a bar code and inhibiting said FIFO storage device from storing said binary signal if it is not representative of a bar code.