Patent ID: 9319685
Filing Date: 2016-04-19
CPC Classification: G06F,H04N

Claim Text:
1. A method comprising: receiving coded media data with a coding device; and performing an 8-point inverse discrete cosine transform (IDCT) with an 8-point IDCT hardware unit of the coding device to transform the coded media data from a frequency domain to a spatial domain, wherein the 8-point IDCT hardware unit includes: an even portion comprising first and second internal factors (A, B) that are related to a first scaled factor (μ) in accordance with a first relationship, wherein the first relationship is defined such that the first scaled factor equals a sum of the first internal factor plus the second internal factor divided by a sum of a first approximation (α) of a cosine of three times a constant pi (π) divided by eight plus a second approximation (β) of a sine of three times the constant pi (π) divided by eight; and an odd portion comprising third, fourth, fifth and sixth internal factors (G, D, E, Z) that are related to a second scaled factor (η) in accordance with a second relationship, wherein the second relationship is defined such that the second scaled factor equals one of the following equations that results in a minimal error: (1) a sum of the third internal factor (G) plus the fourth internal factor (D) divided by a sum of a third approximation (γ) of a cosine of the constant pi divided by sixteen plus a fourth approximation (δ) of a sine of the constant pi divided by sixteen; (2) a sum of the third internal factor (G) plus the fifth internal factor (E) divided by a sum of the third approximation (γ) plus a fifth approximation (ε) of a cosine of three times the constant pi divided by 16; (3) a sum of the third internal factor (G) plus the sixth internal factor (Z) divided by a sum of the third approximation (γ) plus a sixth approximation (ζ) of a sine of three times the constant pi divided by 16; (4) a sum of the fourth internal factor (D) plus the fifth internal factor (E) divided by a sum of the fourth approximation (δ) plus the fifth approximation (ε); (5) a sum of the fourth internal factor (D) plus the sixth internal factor (Z) divided by a sum of the fourth approximation (δ) plus the sixth approximation (ζ); and (6) a sum of the fifth internal factor (E) plus the sixth internal factor (Z) divided by a sum of the fifth approximation (ε) plus the sixth approximation (ζ).