| 摘要 |
Video signal compression apparatus includes a memory (12, 14) for storing tw o fields of image data and providing fields of image data separated by one frame intervals. Image data from corresponding fields of successive frames are subtracted (16) to generate fie ld differences. The field differences are accumulated (18) over respective fiel d intervals, and the sum is compared (20) against a pred etermined value. If a sum of differences over a field is less than the predetermined v alue, the most recent field is considered to be redundan t and may be excised. After respective fields are excised (21), frames of video si gnal are composed (25) from the remaining fields. The fi eld types (e.g., odd or even) of the fields in the memory are determined (11), a nd the data is accessed from the respective fields in me mory such that data from odd and even fields occupy odd and even lines in the com posed frames respectively. Flags (DF, DT) are associated with composed frames to indicate which fields contain data associated with e xcised fields, and which field of the composed frames sh ould be displayed first. |
