Process for synchronizing the scanning circuit of an image display device

Claim 1

A process for the synchronization of the scanning circuit of an image display device incorporating an input buffer, processing means making it possible to reconstitute an image I entering the buffer, display storage means in which the images are recorded after processing, and control means including a display clock and able to control the reading and writing of images in said display storage means, said images being acquired by a camera having a scanning circuit controlled by a given acquisition clock, said process comprising the steps of clearing permanently the input buffer; applying an arbitrary clock signal independent of the image synchronization of the signal received by the scanning circuit of the image display device; controlling the reading and writing of the display storage means in order to obtain at least one of repetitions of images on display when the acquisition clock is shown and suppressions of images on display when the acquisition clock is slower then the display clock and suppression of images or display when the acquisition clock is faster then the display clock so as to absorb any frequency difference between the synchronization clock of the device and another clock; using a fast image compression so as not to disturb the reading/writing mechanisms, subdividing the display storage means into at least two storage fields, each having at least the size of a complete image, controlling the processing of said image I while said image is recorded in the input buffer, the recording of said image I being controlled during processing in one of the storage fields, then either: authorizing the reading of said one of the fields in which said image I has been recorded only if the processing of a new image has been completed, otherwise controlling a new reading of the content of the other field and authorizing the processing of the new image only when a switching from the one field to the other field has taken place; or, with the processing of said image I completed: continuing the reading of the other field containing an already recorded image so as to read said image once more than the other images; or controlling the reading of the one field so as to display the recorded image which has just been processed and display once more than the other images an image which has previously been processed and recorded in the other field.