Abstract: A storage device 500 includes an input 405 for receiving a digital video stream complying with a predetermined video encoding standard via a digital video communication system. The stream includes a sequence of digital video frames, a sequence of program clock reference stamps (PCR) and a sequence of video presentation time stamps (PTS). A time-base modifier 510 replaces the PTS's by respective modified video presentation time stamps (M-PTS) based on a constant predetermined frame time between successive presentation time stamps and replaces the PCR's by respective modified program clock reference stamps (M-PCR) by scaling the PCR's using a scaling factor that depends on a ratio of an expected time between a video presentation time stamp j and a preceding video presentation time stamp j-n and an actual time between the video presentation time stamp j and the preceding video presentation time stamp j-n, where j?n>0. The expected time is n times the predetermined frame time.

Abstract: A storage device 500 includes an input 405 for receiving a digital video stream complying with a predetermined video encoding standard via a digital video communication system. The stream includes a sequence of digital video frames, a sequence of program clock reference stamps (PCR) and a sequence of video presentation time stamps (PTS). A time-base modifier 510 replaces the PTS's by respective modified video presentation time stamps (M-PTS) based on a constant predetermined frame time between successive presentation time stamps and replaces the PCR's by respective modified program clock reference stamps (M-PCR) by scaling the PCR's using a scaling factor that depends on a ratio of an expected time between a video presentation time stamp j and a preceding video presentation time stamp j?n and an actual time between the video presentation time stamp j and the preceding video presentation time stamp j?n, where j?n>0. The expected time is n times the predetermined frame time.

Abstract: A video encoder is usually designed to have a given performance at a given resolution. For example, MPEG2 encoders are known that compress video at ‘601’ resolution (720×576 pixels) into IPPP sequences using 2 MB of RAM. The invention provides the feature of selectably (82a, 82b) encoding images in a lower resolution mode. The spare capacity of resources in the low-resolution mode (e.g. memory capacity and memory bandwidth) is used to improve the performance (e.g. higher image quality, lower bit rate). More particularly, the RAM (81) and motion estimator (9) required for producing P-pictures in the high-resolution mode are arranged (83, 84) to produce B-pictures in the low-resolution mode.