Patent ID: 6950463

Claim:
In a system that receives an input signal, the input signal including a video stream that is compressed, wherein a bit rate of the video stream is higher than a desired bit rate, a method for transcoding the video stream such that the bit rate of the video stream is reduced, the method comprising acts of: obtaining original sets of quantized discrete cosine transform coefficients from the video stream corresponding to macroblock data; updating original quantization level of the original sets of quantized discrete cosine transform coefficients to a new quantization level, wherein updating the original quantization level includes at least one of: an act of computing a matrix ratio between a new quantization matrix and a current quantization matrix of the video stream; or an act of computing a scale ratio between a new quantization scale and a current quantization scale of the video stream; and an act of refraining from computing either the matrix ratio or the scale ratio; generating new sets of discrete cosine transform coefficients using the new quantization level such that the new sets of discrete cosine transform coefficients are more coarsely quantized than the original sets of quantized discrete cosine transform coefficients; and encoding the new discrete cosine transform coefficients, wherein fewer bits are needed to encode the new sets of discrete cosine transform coefficients.