Fix a Makefile typo.

[fjl] / idct_float.c

diff --git a/idct_float.c b/idct_float.c
index c8bde1b236ac80c3bc5f5380fc5adcbd9569bc77..34ff5b690cabb463f1e156ba573b6cd3e865895c 100644 (file)
--- a/idct_float.c
+++ b/idct_float.c
@@ -50,9 +50,11 @@ static inline void idct1d_float(double y0, double y1, double y2, double y3, doub
        // constants
        static const double a1 = 0.7071067811865474;   // sqrt(2)
        static const double a2 = 0.5411961001461971;   // cos(3/8 pi) * sqrt(2)
-       static const double a3 = a1;
+       // static const double a3 = a1;
+       static const double a3 = 0.7071067811865474;
        static const double a4 = 1.3065629648763766;   // cos(pi/8) * sqrt(2)
-       static const double a5 = 0.5 * (a4 - a2);
+       // static const double a5 = 0.5 * (a4 - a2);
+       static const double a5 = 0.3826834323650897;
 
        // phase 1
        const double p1_0 = y0;
@@ -157,12 +159,12 @@ void idct_float(const int16_t* input, const void* userdata, uint8_t* output)
                             temp2);
                for (unsigned x = 0; x < DCTSIZE; ++x) {
                        const double val = temp2[x];
-                       if (val < 0.0) {
+                       if (val < -128.0) {
                                output[y * DCTSIZE + x] = 0;
-                       } else if (val >= 255.0) {
+                       } else if (val >= 127.0) {
                                output[y * DCTSIZE + x] = 255;
                        } else {
-                               output[y * DCTSIZE + x] = (uint8_t)(val + 0.5);
+                               output[y * DCTSIZE + x] = (uint8_t)(val + 128.5);
                        }
                }
        }