From 57b1eb9f75b04571063ddec316e290c216c114ac Mon Sep 17 00:00:00 2001 From: Christophe Gisquet Date: Fri, 14 Feb 2014 15:03:08 +0000 Subject: dcadsp: scan coefficients linearly in dca_lfe_fir This change is inspired by x86 asm where it frees a register. Signed-off-by: Janne Grunau --- libavcodec/dcadsp.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) (limited to 'libavcodec/dcadsp.c') diff --git a/libavcodec/dcadsp.c b/libavcodec/dcadsp.c index 8fc49cebda..294a1b2736 100644 --- a/libavcodec/dcadsp.c +++ b/libavcodec/dcadsp.c @@ -36,22 +36,20 @@ static inline void dca_lfe_fir(float *out, const float *in, const float *coefs, int decifactor) { - float *out2 = out + decifactor; - const float *cf0 = coefs; - const float *cf1 = coefs + 256; + float *out2 = out + 2 * decifactor - 1; + int num_coeffs = 256 / decifactor; int j, k; /* One decimated sample generates 2*decifactor interpolated ones */ for (k = 0; k < decifactor; k++) { float v0 = 0.0; float v1 = 0.0; - for (j = 0; j < 256 / decifactor; j++) { - float s = in[-j]; - v0 += s * *cf0++; - v1 += s * *--cf1; + for (j = 0; j < num_coeffs; j++, coefs++) { + v0 += in[-j] * *coefs; + v1 += in[j + 1 - num_coeffs] * *coefs; } *out++ = v0; - *out2++ = v1; + *out2-- = v1; } } -- cgit v1.2.3