A method for reducing video data to obtain reduced video data, the method comprising: extracting compressed moving-picture data and compressed audio data from the video data; extracting intra-frames from the compressed moving-picture data; extracting a set of predicted frames from the compressed moving-picture data; maintaining a data structure that organizes prime data elements, wherein each prime data element comprises a sequence of bytes; losslessly reducing the intra-frames to obtain losslessly-reduced intra-frames, wherein losslessly reducing the intra-frames comprises, for each intra-frame, identifying a first set of prime data elements by using the intra-frame to perform a first content-associative lookup on a data structure that organizes prime data elements based on their contents, and using the first set of prime data elements to losslessly reduce the intra-frame to obtain (i) if the intra-frame is a duplicate of a prime data element in the first set of prime data elements, a reference to the prime data element, or (ii) if the intra-frame is not a duplicate of any prime data elements in the first set of prime data elements, a reference to one or more prime data elements in the first set of prime data elements, and a sequence of transformations that derives the intra-frame from the one or more prime data elements; and wherein the reduced video data comprises the losslessly-reduced intra-frames, prime data elements referenced by the losslessly-reduced intra-frames, the set of predicted frames, and the compressed audio data. extracting compressed moving-picture data and compressed audio data from the video data; extracting intra-frames from the compressed moving-picture data; extracting a set of predicted frames from the compressed moving-picture data; maintaining a data structure that organizes prime data elements, wherein each prime data element comprises a sequence of bytes; losslessly reducing the intra-frames to obtain losslessly-reduced intra-frames, wherein losslessly reducing the intra-frames comprises, for each intra-frame, identifying a first set of prime data elements by using the intra-frame to perform a first content-associative lookup on a data structure that organizes prime data elements based on their contents, and using the first set of prime data elements to losslessly reduce the intra-frame to obtain (i) if the intra-frame is a duplicate of a prime data element in the first set of prime data elements, a reference to the prime data element, or (ii) if the intra-frame is not a duplicate of any prime data elements in the first set of prime data elements, a reference to one or more prime data elements in the first set of prime data elements, and a sequence of transformations that derives the intra-frame from the one or more prime data elements; and identifying a first set of prime data elements by using the intra-frame to perform a first content-associative lookup on a data structure that organizes prime data elements based on their contents, and using the first set of prime data elements to losslessly reduce the intra-frame to obtain (i) if the intra-frame is a duplicate of a prime data element in the first set of prime data elements, a reference to the prime data element, or (ii) if the intra-frame is not a duplicate of any prime data elements in the first set of prime data elements, a reference to one or more prime data elements in the first set of prime data elements, and a sequence of transformations that derives the intra-frame from the one or more prime data elements; and wherein the reduced video data comprises the losslessly-reduced intra-frames, prime data elements referenced by the losslessly-reduced intra-frames, the set of predicted frames, and the compressed audio data.