From d752509b7437beefac079021fc5ecbd4e27df6b5 Mon Sep 17 00:00:00 2001 From: Mans Rullgard Date: Sun, 5 Aug 2012 22:22:10 +0100 Subject: Use log2(x) instead of log(x) / log(2) Signed-off-by: Mans Rullgard --- avconv.c | 2 +- avprobe.c | 2 +- libavcodec/imc.c | 4 ++-- libavcodec/snowenc.c | 2 +- 4 files changed, 5 insertions(+), 5 deletions(-) diff --git a/avconv.c b/avconv.c index 2bc9d82378..83ff8b45e1 100644 --- a/avconv.c +++ b/avconv.c @@ -820,7 +820,7 @@ static void print_report(int is_last_report, int64_t timer_start) if (qp >= 0 && qp < FF_ARRAY_ELEMS(qp_histogram)) qp_histogram[qp]++; for (j = 0; j < 32; j++) - snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "%X", (int)lrintf(log(qp_histogram[j] + 1) / log(2))); + snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "%X", (int)lrintf(log2(qp_histogram[j] + 1))); } if (enc->flags&CODEC_FLAG_PSNR) { int j; diff --git a/avprobe.c b/avprobe.c index 28746bf18e..8107e54531 100644 --- a/avprobe.c +++ b/avprobe.c @@ -468,7 +468,7 @@ static char *value_string(char *buf, int buf_size, double val, const char *unit) int index; if (unit == unit_byte_str && use_byte_value_binary_prefix) { - index = (int) (log(val)/log(2)) / 10; + index = (int) log2(val) / 10; index = av_clip(index, 0, FF_ARRAY_ELEMS(binary_unit_prefixes) - 1); val /= pow(2, index * 10); prefix_string = binary_unit_prefixes[index]; diff --git a/libavcodec/imc.c b/libavcodec/imc.c index 95495bff96..e452baf39b 100644 --- a/libavcodec/imc.c +++ b/libavcodec/imc.c @@ -342,7 +342,7 @@ static void imc_decode_level_coefficients(IMCContext *q, int *levlCoeffBuf, // maybe some frequency division thingy flcoeffs1[0] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125 - flcoeffs2[0] = log(flcoeffs1[0]) / log(2); + flcoeffs2[0] = log2f(flcoeffs1[0]); tmp = flcoeffs1[0]; tmp2 = flcoeffs2[0]; @@ -414,7 +414,7 @@ static int bit_allocation(IMCContext *q, IMCChannel *chctx, highest = FFMAX(highest, chctx->flcoeffs1[i]); for (i = 0; i < BANDS - 1; i++) - chctx->flcoeffs4[i] = chctx->flcoeffs3[i] - log(chctx->flcoeffs5[i]) / log(2); + chctx->flcoeffs4[i] = chctx->flcoeffs3[i] - log2f(chctx->flcoeffs5[i]); chctx->flcoeffs4[BANDS - 1] = limit; highest = highest * 0.25; diff --git a/libavcodec/snowenc.c b/libavcodec/snowenc.c index 2eaf923540..481dc1a503 100644 --- a/libavcodec/snowenc.c +++ b/libavcodec/snowenc.c @@ -1529,7 +1529,7 @@ static void update_last_header_values(SnowContext *s){ } static int qscale2qlog(int qscale){ - return rint(QROOT*log(qscale / (float)FF_QP2LAMBDA)/log(2)) + return rint(QROOT*log2(qscale / (float)FF_QP2LAMBDA)) + 61*QROOT/8; ///< 64 > 60 } -- cgit v1.2.3