| 摘要 |
In general, techniques are described that provide for 4x4 transforms for media coding. A number of different 4x4 transforms are described that adhere to these techniques. As one example, an apparatus includes a 4x4 discrete cosine transform (DCT) hardware unit. The DCT hardware unit implements an orthogonal 4x4 DCT having an odd portion that applies first and second internal factors (C, S) that are related to a scaled factor (?) such that the scaled factor equals a square root of a sum of a square of the first internal factor (C) plus a square of the second internal factor (S). The 4x4 DCT hardware unit applies the 4x4 DCT implementation to media data to transform the media data from a spatial domain to a frequency domain. As another example, an apparatus implements a non-orthogonal 4x4 DCT to improve coding gain. |
