| 摘要 |
An apparatus for processing a video signal to monitor its level distribution with respect to time is disclosed. The level distribution 503 for a current video frame 501 is generated by a processor 502. The level distribution 503 is organized as one-dimensional array addressed by level values, and it defines the number of pixels in the current video frame having each possible level value. The current level distribution is added to a display buffer 506, which is organized as two-dimensional array addressed by level values and level distribution. As new level distributions are generated for the succession of video frames in the video signal, they are added to the display buffer. The level distributions may be generated directly from a serial digital video datastream, from the rasters of the video frames, or from a raster containing the waveform of the video signal for every line of the whole of the current video frame, as it would be displayed on a digital waveform monitor. |
