Fast Conversion of H.264/AVC Integer Transform Coefficients into DCT Coefficients
نویسندگان
چکیده
In this paper we propose a fast method to convert H.264/AVC Integer Transform (IT) coefficients to Discrete Cosine Transform (DCT) coefficients for applications in video transcoding. We derive the transform kernel matrix for converting, in the transform domain, four IT coefficient blocks into one 8 8 × DCT block of coefficients. By exploiting the symmetry of this matrix, we show that the proposed conversion method requires fewer computations than its equivalent in the pixel domain. An integer approximation for the kernel matrix is also proposed. The experimental results show that a negligible error is introduced, while the computational complexity can be significantly reduced.
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