Abstract: Disclosed is a method for clipping a segment from a video file having a multiplicity of video frames. Preferably, at least some of the frames in the video file are encoded as predicted frames. The method includes selecting a mark-in location in the video file that defines the beginning of the clipped segment. A mark-out location defining the end of the clipped segment is also selected in the video file. Once the mark-in and mark-out locations are selected, the method decodes a first frame associated with one of the mark-in location and the mark-out location. The first frame is preferably a predictive frame that has an associated first format. The first frame is then re-encoded into a second format and stored. The method then proceeds to create a clipped segment that includes the re-encoded first frame.

Abstract: Disclosed are methods and apparatuses for stitching a first and second audiovisual segment together. By way of example, each audiovisual segment has a multiplicity of audio frames including a first audio frame, a second audio frame that sequentially follows the first audio frame and a last audio frame. The audiovisual segment further includes a multiplicity of video frames having a first video frame and a last video frame. The method includes the step of aligning an initial audio frame in the first audiovisual segment with the first video frame in the first audiovisual segment. The first audio frame from the first audiovisual segment is designated as the initial audio frame when a tab error associated with the first audio frame from the first audiovisual segment is less than about half a frame.

Abstract: A method for copying a segment from a video file having a multiplicity of video frames, where at least some of the frames are encoded as predicted frames. The method includes the steps of selecting a mark-in location in the video file such that the mark-in location defines the beginning of the copied segment. Once the mark-in location is selected, each of the frames positioned between the mark-in location and a final group frame associated with a group of frames that includes the mark-in location are decoded. Each decoded frame will have an associated first format. The decoded frames are then re-encoded into an associated second format such that the re-encoded second format of at least one of the decoded frames is different than its associated first format. The re-encoded frames are then stored. The method then generates a copied segment that includes at least the re-encoded frames.

Abstract: Disclosed are methods and apparatuses for seeking within audiovisual files. A seeking engine is implemented to efficiently locate target video frames without having to laboriously decode and index each and every video frame in an audiovisual file. Further, a seeking engine is capable of frame accurately determining the number of frames in a video file by identifying the last GOP header in the video file, and then identifying a last video frame in the file. The last video frame in the file is identified by reading each video frame's picture header (i.e., within the last GOP) and determining which picture header produces a larger temporal reference number. The video frame having the largest temporal number is therefore the last video frame in the video file. In addition, the seeking engine is capable of associating an identified video frame with a closest audio frame to complete an audio-to-video seek.

Abstract: An error measurement and reduction method, including the steps of inducing a high error rate in a mass storage device memory system to determine rapidly and independently the optimal pattern sensitivity, pulse pairing, and window centering error parameters for the system. In a preferred embodiment, the system error rate is then reduced by setting at least one, and preferably all three, of the error parameters to its optimal value. The inventive system includes means for performing the inventive method, and preferably includes computer-controllable means for independently adjusting the pattern sensitivity and pulse pairing error parameters associated with each read/write head of the system, and for adjusting the window centering error parameter associated with the system.