From a8cc6a74547e6485f3aa9fe597f5d1dc176cca8a Mon Sep 17 00:00:00 2001 From: Thom Johansen Date: Sun, 29 Jan 2006 02:10:28 +0000 Subject: Initial multi-band EQ support for software codec platforms. Now go start making that user interface! git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8478 a1c6a512-1295-4272-9138-f99709370657 --- apps/dsp.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) (limited to 'apps/dsp.c') diff --git a/apps/dsp.c b/apps/dsp.c index 19cb669a06..b2fc0ce7a2 100644 --- a/apps/dsp.c +++ b/apps/dsp.c @@ -19,6 +19,7 @@ #include #include #include "dsp.h" +#include "eq.h" #include "kernel.h" #include "playback.h" #include "system.h" @@ -166,10 +167,21 @@ struct crossfeed_data int index; }; +/* Current setup is one lowshelf filters, three peaking filters and one + highshelf filter. Varying the number of shelving filters make no sense, + but adding peaking filters are possible. */ +struct eq_state { + char enabled[5]; /* Flags for active filters */ + struct eqfilter ls; + struct eqfilter pk[3]; + struct eqfilter hs; +}; + static struct dsp_config dsp_conf[2] IBSS_ATTR; static struct dither_data dither_data[2] IBSS_ATTR; static struct resample_data resample_data[2] IBSS_ATTR; struct crossfeed_data crossfeed_data IBSS_ATTR; +static struct eq_state eq_data; static int pitch_ratio = 1000; @@ -608,6 +620,25 @@ static void apply_crossfeed(long* src[], int count) } #endif +/* Apply EQ filters to those bands that have got it switched on. */ +void eq_process(long **x, unsigned num) +{ + int i; + unsigned int channels = dsp->stereo_mode != STEREO_MONO ? 2 : 1; + + /* filter configuration currently is 1 low shelf filter, 3 band peaking + filters and 1 high shelf filter, in that order. + */ + if (eq_data.enabled[0]) + eq_filter(x, &eq_data.ls, num, channels, EQ_SHELF_SHIFT); + for (i = 0; i < 3; i++) { + if (eq_data.enabled[1 + i]) + eq_filter(x, &eq_data.pk[i], num, channels, EQ_PEAK_SHIFT); + } + if (eq_data.enabled[4]) + eq_filter(x, &eq_data.hs, num, channels, EQ_SHELF_SHIFT); +} + /* Apply a constant gain to the samples (e.g., for ReplayGain). May update * the src array if gain was applied. * Note that this must be called before the resampler. @@ -713,6 +744,9 @@ long dsp_process(char* dst, char* src[], long size) samples = resample(tmp, samples); if (dsp->crossfeed_enabled && dsp->stereo_mode != STEREO_MONO) apply_crossfeed(tmp, samples); + /* TODO: Might want to wrap this with a generic eq_enabled when the + settings are in place */ + eq_process(tmp, samples); write_samples((short*) dst, tmp, samples); written += samples; dst += samples * sizeof(short) * 2; -- cgit v1.2.3