From 521fe1d2da7dde4db9abe7d0c1e11582d49cc4f0 Mon Sep 17 00:00:00 2001 From: Benjamin Larsson Date: Tue, 14 Nov 2006 18:54:42 +0000 Subject: Remove log2() usage. Originally committed as revision 7063 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/imc.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'libavcodec/imc.c') diff --git a/libavcodec/imc.c b/libavcodec/imc.c index d9db73599c..5b5f23b92b 100644 --- a/libavcodec/imc.c +++ b/libavcodec/imc.c @@ -80,7 +80,6 @@ typedef struct { float sqrt_tab[30]; GetBitContext gb; VLC huffman_vlc[4][4]; - float flcf1, flcf2; int decoder_reset; float one_div_log2; @@ -125,8 +124,6 @@ static int imc_decode_init(AVCodecContext * avctx) q->last_fft_im[i] = 0; } - q->flcf1 = log2(10) * 0.05703125; - q->flcf2 = log2(10) * 0.25; /* Generate a square root table */ @@ -236,8 +233,8 @@ static void imc_decode_level_coefficients(IMCContext* q, int* levlCoeffBuf, floa float tmp, tmp2; //maybe some frequency division thingy - flcoeffs1[0] = 20000.0 / pow (2, levlCoeffBuf[0] * q->flcf1); - flcoeffs2[0] = log2(flcoeffs1[0]); + flcoeffs1[0] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125 + flcoeffs2[0] = log(flcoeffs1[0])/log(2); tmp = flcoeffs1[0]; tmp2 = flcoeffs2[0]; @@ -255,7 +252,7 @@ static void imc_decode_level_coefficients(IMCContext* q, int* levlCoeffBuf, floa level -=16; tmp *= imc_exp_tab[15 + level]; - tmp2 += q->flcf2 * level; + tmp2 += 0.83048 * level; // 0.83048 = log2(10) * 0.25 flcoeffs1[i] = tmp; flcoeffs2[i] = tmp2; } @@ -273,7 +270,7 @@ static void imc_decode_level_coefficients2(IMCContext* q, int* levlCoeffBuf, flo flcoeffs1[i] = 0; if(levlCoeffBuf[i] < 16) { flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i]; - flcoeffs2[i] = (levlCoeffBuf[i]-7) * q->flcf2 + flcoeffs2[i]; + flcoeffs2[i] = (levlCoeffBuf[i]-7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25 } else { flcoeffs1[i] = old_floor[i]; } -- cgit v1.2.3