From 85aedd00057ffa1842703bc87b2c864a4d19822b Mon Sep 17 00:00:00 2001 From: pl Date: Sun, 10 Mar 2002 13:53:38 +0000 Subject: [PATCH] new smoothing method ('#define AVG 2' to enable'n'test it) should be better and smoother but still some glitches in it :/ git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@5026 b3059339-0415-0410-9bf9-f77b7e298cf2 --- libao2/pl_volnorm.c | 118 ++++++++++++++++++++++++++++++++++++-------- 1 file changed, 97 insertions(+), 21 deletions(-) diff --git a/libao2/pl_volnorm.c b/libao2/pl_volnorm.c index 569e861aff..4de14ad925 100644 --- a/libao2/pl_volnorm.c +++ b/libao2/pl_volnorm.c @@ -7,12 +7,21 @@ * License: GPLv2 * Author: pl (c) 2002 and beyond... * - * Sources: some ideas from volnorm for xmms + * Sources: some ideas from volnorm plugin for xmms * * */ #define PLUGIN +/* Values for AVG: + * 1: uses a 1 value memory and coefficients new=a*old+b*cur (with a+b=1) + * + * 2: uses several samples to smooth the variations (standard weighted mean + * on past samples) + * + * */ +#define AVG 1 + #include #include #include @@ -36,9 +45,11 @@ LIBAO_PLUGIN_EXTERN(volnorm) // and has to be in [MUL_MIN, MUL_MAX] #define MUL_INIT 1.0 #define MUL_MIN 0.1 -#define MUL_MAX 15.0 +#define MUL_MAX 5.0 static float mul; + +#if AVG==1 // "history" value of the filter static float lastavg; @@ -47,17 +58,44 @@ static float lastavg; #define SMOOTH_MUL 0.06 #define SMOOTH_LASTAVG 0.06 + +#elif AVG==2 +// Size of the memory array +// FIXME: should depend on the frequency of the data (should be a few seconds) +#define NSAMPLES 128 + +// Indicates where to write (in 0..NSAMPLES-1) +static int idx; +// The array +static struct { + float avg; // average level of the sample + int32_t len; // sample size (weight) +} mem[NSAMPLES]; + +// If summing all the mem[].len is lower than MIN_SAMPLE_SIZE bytes, then we +// choose to ignore the computed value as it's not significant enough +// FIXME: should depend on the frequency of the data (0.5s maybe) +#define MIN_SAMPLE_SIZE 32000 + +#else +// Kab00m ! +#error "Unknown AVG" +#endif + + // Some limits #define MIN_S16 -32768 #define MAX_S16 32767 -// ideal average level +// "Ideal" level #define MID_S16 (MAX_S16 * 0.25) -// silence level -#define SIL_S16 (MAX_S16 * 0.02) +// Silence level +// FIXME: should be relative to the level of the samples +#define SIL_S16 (MAX_S16 * 0.01) -// local data + +// Local data static struct { int inuse; // This plugin is in use TRUE, FALSE int format; // sample fomat @@ -101,13 +139,23 @@ static void uninit(){ // empty buffers static void reset(){ + int i; mul = MUL_INIT; switch(ao_plugin_data.format) { case(AFMT_S16_LE): +#if AVG==1 lastavg = MID_S16; +#elif AVG==2 + for(i=0; i < NSAMPLES; ++i) { + mem[i].len = 0; + mem[i].avg = 0; + } + idx = 0; +#endif + break; default: - fprintf(stderr,"[pl_volnorm] internal inconsistency - please bugreport.\n"); + fprintf(stderr,"[pl_volnorm] internal inconsistency - bugreport !\n"); *(char *) 0 = 0; } } @@ -124,13 +172,17 @@ static int play(){ int16_t* data=(int16_t*)ao_plugin_data.data; int len=ao_plugin_data.len / 2; // 16 bits samples - int32_t i; - register int32_t tmp; - register float curavg; - float newavg; - float neededmul; + int32_t i, tmp; + float curavg, newavg; - // average of the current samples +#if AVG==1 + float neededmul; +#elif AVG==2 + float avg; + int32_t totallen; +#endif + + // Evaluate current samples average level curavg = 0.0; for (i = 0; i < len ; ++i) { tmp = data[i]; @@ -138,6 +190,9 @@ static int play(){ } curavg = sqrt(curavg / (float) len); + // Evaluate an adequate 'mul' coefficient based on previous state, current + // samples level, etc +#if AVG==1 if (curavg > SIL_S16) { neededmul = MID_S16 / ( curavg * mul); mul = (1.0 - SMOOTH_MUL) * mul + SMOOTH_MUL * neededmul; @@ -145,10 +200,27 @@ static int play(){ // Clamp the mul coefficient CLAMP(mul, MUL_MIN, MUL_MAX); } +#elif AVG==2 + avg = 0.0; + totallen = 0; + + for (i = 0; i < NSAMPLES; ++i) { + avg += mem[i].avg * (float) mem[i].len; + totallen += mem[i].len; + } + + if (totallen > MIN_SAMPLE_SIZE) { + avg /= (float) totallen; + if (avg >= SIL_S16) { + mul = (float) MID_S16 / avg; + CLAMP(mul, MUL_MIN, MUL_MAX); + } + } +#endif // Scale & clamp the samples - for (i=0; i < len ; ++i) { - tmp = data[i] * mul; + for (i = 0; i < len ; ++i) { + tmp = mul * data[i]; CLAMP(tmp, MIN_S16, MAX_S16); data[i] = tmp; } @@ -156,13 +228,17 @@ static int play(){ // Evaluation of newavg (not 100% accurate because of values clamping) newavg = mul * curavg; -#if 0 - printf("time = %d len = %d curavg = %6.0f lastavg = %6.0f newavg = %6.0f\n" - " needed_m = %2.2f m = %2.2f\n\n", - time(NULL), len, curavg, lastavg, newavg, neededmul, mul); -#endif - + // Stores computed values for future smoothing +#if AVG==1 lastavg = (1.0 - SMOOTH_LASTAVG) * lastavg + SMOOTH_LASTAVG * newavg; + //printf("\rmul=%02.1f ", mul); +#elif AVG==2 + mem[idx].len = len; + mem[idx].avg = newavg; + idx = (idx + 1) % NSAMPLES; + //printf("\rmul=%02.1f (%04dKiB) ", mul, totallen/1024); +#endif + //fflush(stdout); break; }