diff --git a/vp8/common/x86/idctllm_mmx.asm b/vp8/common/x86/idctllm_mmx.asm index 43735bc4b6f41521acdc42b0b75a9a91329c9e3a..465626b8fa3d1e7be91476a8eb43dbd677cc9929 100644 --- a/vp8/common/x86/idctllm_mmx.asm +++ b/vp8/common/x86/idctllm_mmx.asm @@ -14,18 +14,18 @@ ; /**************************************************************************** ; * Notes: ; * -; * This implementation makes use of 16 bit fixed point verio of two multiply +; * This implementation makes use of 16 bit fixed point version of two multiply ; * constants: ; * 1. sqrt(2) * cos (pi/8) -; * 2. sqrt(2) * sin (pi/8) -; * Becuase the first constant is bigger than 1, to maintain the same 16 bit -; * fixed point prrcision as the second one, we use a trick of +; * 2. sqrt(2) * sin (pi/8) +; * Because the first constant is bigger than 1, to maintain the same 16 bit +; * fixed point precision as the second one, we use a trick of ; * x * a = x + x*(a-1) ; * so ; * x * sqrt(2) * cos (pi/8) = x + x * (sqrt(2) *cos(pi/8)-1). ; * -; * For the second constant, becuase of the 16bit version is 35468, which -; * is bigger than 32768, in signed 16 bit multiply, it become a negative +; * For the second constant, because of the 16bit version is 35468, which +; * is bigger than 32768, in signed 16 bit multiply, it becomes a negative ; * number. ; * (x * (unsigned)35468 >> 16) = x * (signed)35468 >> 16 + x ; *