Discrete cosine transform method
AssigneeSony Corporation
InventorNozomu Ozaki
Life of this patent
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Abstract
When a weighted calculation in which a cosine-transformed coefficient is multiplied with diagonal matrixes from the right and left direction is carried out, a new transform matrix is obtained by previously multiplying a weighting diagonal matrix and the cosine transform matrix and input data is transformed by using the new transform matrix. Thus, a circuit scale can be reduced, the processing steps can be simplified, and the cost can be reduced. When a weighted calculation in which a cosine transformed coefficient C is multiplied with a diagonal matrix W from the right and left directions is carried out, the weighted cosine transform is carried out by using a new transform matrix Fw which results from previously multiplying the weighting diagonal matrix W and the cosine transform matrix F.
Claims5
A method of compressing audio and/or video signals, comprising the steps of:
- receiving said audio and/or video signals at an audio and/or video input port;
- passing said audio and/or video signals from said audio and/or video input port to a transform/weighting means;
- cosine transforming/weighting said audio and/or video signals with a weighted cosine transform matrix formed by multiplying a weighting diagonal matrix and a forward cosine transform matrix to produce transformed signals;
- passing said transformed signals to a quantizing means distinct from said transform/weighting means to form quantized transformed signals;
- and
- passing said quantized transformed signals to an audio and/or video output port for transmission.
A method of compressing audio and/or video signals, comprising the steps of:
- receiving said audio and/or video signals at an audio and/or video input port;
- passing said audio and/or video signals from said audio and/or video input port to a transform/weighting means;
- weighted cosine transforming said audio and/or video signals with a weighted cosine transform matrix formed by multiplying a weighting diagonal matrix and a forward cosine transform matrix to produce processed signals;
- weighted cosine transforming said processed signals with a transpose of said weighted cosine transform matrix to produce transformed signals;
- passing said transformed signals to a quantizing means distinct form said transform/weighting means to form quantized transformed signals;
- and
- passing said quantized transformed signals to an audio and/or video output port for transmission.
Dependencies are inferred from the claim text.