Frame-accurate editing of encoded A/V sequences
AssigneeKoninklijke Philips Electronics N.V.
InventorsAlexis S. Ashley, Octavius J. Morris
Life of this patent
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Abstract
A method and apparatus are provided for generating bridge segments to enable editing jumps to be made from one A/V segment to another while handling timing and frame constraints imposed by the A/V segment compliance with coding conventions, such as MPEG. The bridge segment is constructed by copying data from the two sequences to be bridged, with some demultiplexing, decoding, remultiplexing and re-encoding of this data to maintain the validity of the edited data stream. Different procedures in terms of copying and/or re-encoding are applied in dependence on the picture encoding types at the source and destination of the edit via the bridging segment.
Claims23
A data processing apparatus, comprising:
- means for reading a first frame sequence of frame-based data and a second frame sequence of frame-based data from a storage device and for editing the first and second frame sequences, to link from a first edit point in the first frame sequence to a second edit point in the second sequence, wherein for each of the stored first and second frame sequences a number of the frames (I-frames) are intra-coded without reference to any other frame of the sequence, a number (P-frames) are respectively coded with reference to one further frame of the sequence, and the remainder (B-frames) are respectively coded with reference to two or more further frames of the sequence;
- and
- joining means for seamlessly joining the first frame sequence to the second frame sequence, said joining means including bridge generation means configured to create a bridge frame sequence to link the first and second edit points by a jump from the first edit point to the bridge frame sequence and a jump from the bridge frame sequence to the second edit point, and by selective incorporation of frames from the stored first and second frame sequences and selective recoding of one or more of the frames within the bridge sequence as determined by the coding type (I,P,B) of the frames from the first and second sequences indicated by the respective edit points.
A method for editing sequences of frame-based data to link from a first edit point in a first frame sequence to a second edit point in a second sequence, wherein for each of the frame sequences a number of the frames (I-frames) are intra-coded, without reference to any other frame of the sequence, a number (P-frames) are respectively coded with reference to one further frame of the sequence, and the remainder (B-frames) are respectively coded with reference to two or more further frames of the sequence, the method including:
- seamlessly joining the first frame sequence to the second frame sequence, said seamlessly joining including creating a bridge frame sequence to link the first and second edit points by a jump from the first edit point to the bridge frame sequence and a jump from the bridge frame sequence to the second edit point, the bridge frame sequence incorporating frames from the first and second frame sequences with selective recoding of frames within the bridge sequence being determined by the coding type (I,P,B) of the frames from the first and second sequences indicated by the respective edit points.
Dependencies are inferred from the claim text.