]> code.delx.au - pulseaudio/blobdiff - src/pulsecore/resampler.c
Add new option to disable remixing from/to LFE and set it to on by default
[pulseaudio] / src / pulsecore / resampler.c
index 3e14c0e78386959aeecf9585b03ef47939932094..0ae029b3fda8169bc1a60d6040f594dbdaa5bfa4 100644 (file)
@@ -1,5 +1,3 @@
-/* $Id$ */
-
 /***
   This file is part of PulseAudio.
 
@@ -29,7 +27,9 @@
 
 #if HAVE_LIBSAMPLERATE
 #include <samplerate.h>
-#endif 
+#endif
+
+#include <speex/speex_resampler.h>
 
 #include <liboil/liboilfuncs.h>
 #include <liboil/liboil.h>
 #include <pulsecore/sconv.h>
 #include <pulsecore/log.h>
 #include <pulsecore/macro.h>
-
-#include "speexwrap.h"
+#include <pulsecore/strbuf.h>
 
 #include "ffmpeg/avcodec.h"
 
 #include "resampler.h"
 
+/* Number of samples of extra space we allow the resamplers to return */
+#define EXTRA_FRAMES 128
+
 struct pa_resampler {
-    pa_resample_method_t resample_method;
+    pa_resample_method_t method;
+    pa_resample_flags_t flags;
+
     pa_sample_spec i_ss, o_ss;
     pa_channel_map i_cm, o_cm;
     size_t i_fz, o_fz, w_sz;
@@ -56,22 +60,32 @@ struct pa_resampler {
     unsigned buf1_samples, buf2_samples, buf3_samples, buf4_samples;
 
     pa_sample_format_t work_format;
-    
+
     pa_convert_func_t to_work_format_func;
     pa_convert_func_t from_work_format_func;
 
-    int map_table[PA_CHANNELS_MAX][PA_CHANNELS_MAX];
-    int map_required;
+    float map_table[PA_CHANNELS_MAX][PA_CHANNELS_MAX];
+    pa_bool_t map_required;
 
     void (*impl_free)(pa_resampler *r);
     void (*impl_update_rates)(pa_resampler *r);
     void (*impl_resample)(pa_resampler *r, const pa_memchunk *in, unsigned in_samples, pa_memchunk *out, unsigned *out_samples);
-    
+    void (*impl_reset)(pa_resampler *r);
+
     struct { /* data specific to the trivial resampler */
         unsigned o_counter;
         unsigned i_counter;
     } trivial;
 
+    struct { /* data specific to the peak finder pseudo resampler */
+        unsigned o_counter;
+        unsigned i_counter;
+
+        float max_f[PA_CHANNELS_MAX];
+        int16_t max_i[PA_CHANNELS_MAX];
+
+    } peaks;
+
 #ifdef HAVE_LIBSAMPLERATE
     struct { /* data specific to libsamplerate */
         SRC_STATE *state;
@@ -88,9 +102,14 @@ struct pa_resampler {
     } ffmpeg;
 };
 
+static int copy_init(pa_resampler *r);
 static int trivial_init(pa_resampler*r);
 static int speex_init(pa_resampler*r);
 static int ffmpeg_init(pa_resampler*r);
+static int peaks_init(pa_resampler*r);
+#ifdef HAVE_LIBSAMPLERATE
+static int libsamplerate_init(pa_resampler*r);
+#endif
 
 static void calc_map_table(pa_resampler *r);
 
@@ -107,7 +126,7 @@ static int (* const init_table[])(pa_resampler*r) = {
     [PA_RESAMPLER_SRC_SINC_FASTEST]        = NULL,
     [PA_RESAMPLER_SRC_ZERO_ORDER_HOLD]     = NULL,
     [PA_RESAMPLER_SRC_LINEAR]              = NULL,
-#endif    
+#endif
     [PA_RESAMPLER_TRIVIAL]                 = trivial_init,
     [PA_RESAMPLER_SPEEX_FLOAT_BASE+0]      = speex_init,
     [PA_RESAMPLER_SPEEX_FLOAT_BASE+1]      = speex_init,
@@ -133,6 +152,8 @@ static int (* const init_table[])(pa_resampler*r) = {
     [PA_RESAMPLER_SPEEX_FIXED_BASE+10]     = speex_init,
     [PA_RESAMPLER_FFMPEG]                  = ffmpeg_init,
     [PA_RESAMPLER_AUTO]                    = NULL,
+    [PA_RESAMPLER_COPY]                    = copy_init,
+    [PA_RESAMPLER_PEAKS]                   = peaks_init,
 };
 
 static inline size_t sample_size(pa_sample_format_t f) {
@@ -151,8 +172,8 @@ pa_resampler* pa_resampler_new(
         const pa_channel_map *am,
         const pa_sample_spec *b,
         const pa_channel_map *bm,
-        pa_resample_method_t resample_method,
-        int variable_rate) {
+        pa_resample_method_t method,
+        pa_resample_flags_t flags) {
 
     pa_resampler *r = NULL;
 
@@ -161,26 +182,43 @@ pa_resampler* pa_resampler_new(
     pa_assert(b);
     pa_assert(pa_sample_spec_valid(a));
     pa_assert(pa_sample_spec_valid(b));
-    pa_assert(resample_method >= 0);
-    pa_assert(resample_method < PA_RESAMPLER_MAX);
+    pa_assert(method >= 0);
+    pa_assert(method < PA_RESAMPLER_MAX);
 
     /* Fix method */
 
-    if (resample_method == PA_RESAMPLER_FFMPEG && variable_rate) {
-        pa_log_info("Resampler 'ffmpeg' cannot do variable rate, reverting to resampler 'auto'." );
-        resample_method = PA_RESAMPLER_AUTO;
+    if (!(flags & PA_RESAMPLER_VARIABLE_RATE) && a->rate == b->rate) {
+        pa_log_info("Forcing resampler 'copy', because of fixed, identical sample rates.");
+        method = PA_RESAMPLER_COPY;
+    }
+
+    if (!pa_resample_method_supported(method)) {
+        pa_log_warn("Support for resampler '%s' not compiled in, reverting to 'auto'.", pa_resample_method_to_string(method));
+        method = PA_RESAMPLER_AUTO;
     }
 
-    if (resample_method == PA_RESAMPLER_AUTO)
-        resample_method = PA_RESAMPLER_SPEEX_FLOAT_BASE + 0;
+    if (method == PA_RESAMPLER_FFMPEG && (flags & PA_RESAMPLER_VARIABLE_RATE)) {
+        pa_log_info("Resampler 'ffmpeg' cannot do variable rate, reverting to resampler 'auto'.");
+        method = PA_RESAMPLER_AUTO;
+    }
+
+    if (method == PA_RESAMPLER_COPY && ((flags & PA_RESAMPLER_VARIABLE_RATE) || a->rate != b->rate)) {
+        pa_log_info("Resampler 'copy' cannot change sampling rate, reverting to resampler 'auto'.");
+        method = PA_RESAMPLER_AUTO;
+    }
+
+    if (method == PA_RESAMPLER_AUTO)
+        method = PA_RESAMPLER_SPEEX_FLOAT_BASE + 3;
 
     r = pa_xnew(pa_resampler, 1);
     r->mempool = pool;
-    r->resample_method = resample_method;
+    r->method = method;
+    r->flags = flags;
 
     r->impl_free = NULL;
     r->impl_update_rates = NULL;
     r->impl_resample = NULL;
+    r->impl_reset = NULL;
 
     /* Fill sample specs */
     r->i_ss = *a;
@@ -188,13 +226,13 @@ pa_resampler* pa_resampler_new(
 
     if (am)
         r->i_cm = *am;
-    else
-        pa_channel_map_init_auto(&r->i_cm, r->i_ss.channels, PA_CHANNEL_MAP_DEFAULT);
+    else if (!pa_channel_map_init_auto(&r->i_cm, r->i_ss.channels, PA_CHANNEL_MAP_DEFAULT))
+        goto fail;
 
     if (bm)
         r->o_cm = *bm;
-    else
-        pa_channel_map_init_auto(&r->o_cm, r->o_ss.channels, PA_CHANNEL_MAP_DEFAULT);
+    else if (!pa_channel_map_init_auto(&r->o_cm, r->o_ss.channels, PA_CHANNEL_MAP_DEFAULT))
+        goto fail;
 
     r->i_fz = pa_frame_size(a);
     r->o_fz = pa_frame_size(b);
@@ -208,28 +246,33 @@ pa_resampler* pa_resampler_new(
 
     calc_map_table(r);
 
-    pa_log_info("Using resampler '%s'", pa_resample_method_to_string(resample_method));
-    
-    if ((resample_method >= PA_RESAMPLER_SPEEX_FIXED_BASE && resample_method <= PA_RESAMPLER_SPEEX_FIXED_MAX) ||
-        (resample_method == PA_RESAMPLER_FFMPEG))
+    pa_log_info("Using resampler '%s'", pa_resample_method_to_string(method));
+
+    if ((method >= PA_RESAMPLER_SPEEX_FIXED_BASE && method <= PA_RESAMPLER_SPEEX_FIXED_MAX) ||
+        (method == PA_RESAMPLER_FFMPEG))
         r->work_format = PA_SAMPLE_S16NE;
-    else if (resample_method == PA_RESAMPLER_TRIVIAL) {
+    else if (method == PA_RESAMPLER_TRIVIAL || method == PA_RESAMPLER_COPY || method == PA_RESAMPLER_PEAKS) {
 
-        if (r->map_required || a->format != b->format) {
+        if (r->map_required || a->format != b->format || method == PA_RESAMPLER_PEAKS) {
 
-            if (a->format == PA_SAMPLE_FLOAT32NE || a->format == PA_SAMPLE_FLOAT32RE)
+            if (a->format == PA_SAMPLE_S32NE || a->format == PA_SAMPLE_S32RE ||
+                a->format == PA_SAMPLE_FLOAT32NE || a->format == PA_SAMPLE_FLOAT32RE ||
+                b->format == PA_SAMPLE_S32NE || b->format == PA_SAMPLE_S32RE ||
+                b->format == PA_SAMPLE_FLOAT32NE || b->format == PA_SAMPLE_FLOAT32RE)
                 r->work_format = PA_SAMPLE_FLOAT32NE;
             else
                 r->work_format = PA_SAMPLE_S16NE;
-            
+
         } else
             r->work_format = a->format;
-        
+
     } else
         r->work_format = PA_SAMPLE_FLOAT32NE;
 
+    pa_log_info("Using %s as working format.", pa_sample_format_to_string(r->work_format));
+
     r->w_sz = sample_size(r->work_format);
-        
+
     if (r->i_ss.format == r->work_format)
         r->to_work_format_func = NULL;
     else if (r->work_format == PA_SAMPLE_FLOAT32NE) {
@@ -253,7 +296,7 @@ pa_resampler* pa_resampler_new(
     }
 
     /* initialize implementation */
-    if (init_table[resample_method](r) < 0)
+    if (init_table[method](r) < 0)
         goto fail;
 
     return r;
@@ -279,7 +322,7 @@ void pa_resampler_free(pa_resampler *r) {
         pa_memblock_unref(r->buf3.memblock);
     if (r->buf4.memblock)
         pa_memblock_unref(r->buf4.memblock);
-    
+
     pa_xfree(r);
 }
 
@@ -313,10 +356,47 @@ size_t pa_resampler_request(pa_resampler *r, size_t out_length) {
     return (((out_length / r->o_fz)*r->i_ss.rate)/r->o_ss.rate) * r->i_fz;
 }
 
+size_t pa_resampler_result(pa_resampler *r, size_t in_length) {
+    pa_assert(r);
+
+    return (((in_length / r->i_fz)*r->o_ss.rate)/r->i_ss.rate) * r->o_fz;
+}
+
+size_t pa_resampler_max_block_size(pa_resampler *r) {
+    size_t block_size_max;
+    pa_sample_spec ss;
+    size_t fs;
+
+    pa_assert(r);
+
+    block_size_max = pa_mempool_block_size_max(r->mempool);
+
+    /* We deduce the "largest" sample spec we're using during the
+     * conversion */
+    ss.channels = (uint8_t) (PA_MAX(r->i_ss.channels, r->o_ss.channels));
+
+    /* We silently assume that the format enum is ordered by size */
+    ss.format = PA_MAX(r->i_ss.format, r->o_ss.format);
+    ss.format = PA_MAX(ss.format, r->work_format);
+
+    ss.rate = PA_MAX(r->i_ss.rate, r->o_ss.rate);
+
+    fs = pa_frame_size(&ss);
+
+    return (((block_size_max/fs - EXTRA_FRAMES)*r->i_ss.rate)/ss.rate)*r->i_fz;
+}
+
+void pa_resampler_reset(pa_resampler *r) {
+    pa_assert(r);
+
+    if (r->impl_reset)
+        r->impl_reset(r);
+}
+
 pa_resample_method_t pa_resampler_get_method(pa_resampler *r) {
     pa_assert(r);
-    
-    return r->resample_method;
+
+    return r->method;
 }
 
 static const char * const resample_methods[] = {
@@ -349,7 +429,9 @@ static const char * const resample_methods[] = {
     "speex-fixed-9",
     "speex-fixed-10",
     "ffmpeg",
-    "auto"
+    "auto",
+    "copy",
+    "peaks"
 };
 
 const char *pa_resample_method_to_string(pa_resample_method_t m) {
@@ -360,6 +442,19 @@ const char *pa_resample_method_to_string(pa_resample_method_t m) {
     return resample_methods[m];
 }
 
+int pa_resample_method_supported(pa_resample_method_t m) {
+
+    if (m < 0 || m >= PA_RESAMPLER_MAX)
+        return 0;
+
+#ifndef HAVE_LIBSAMPLERATE
+    if (m <= PA_RESAMPLER_SRC_LINEAR)
+        return 0;
+#endif
+
+    return 1;
+}
+
 pa_resample_method_t pa_parse_resample_method(const char *string) {
     pa_resample_method_t m;
 
@@ -370,44 +465,435 @@ pa_resample_method_t pa_parse_resample_method(const char *string) {
             return m;
 
     if (!strcmp(string, "speex-fixed"))
-        return PA_RESAMPLER_SPEEX_FIXED_BASE + 0;
+        return PA_RESAMPLER_SPEEX_FIXED_BASE + 3;
 
     if (!strcmp(string, "speex-float"))
-        return PA_RESAMPLER_SPEEX_FLOAT_BASE + 0;
+        return PA_RESAMPLER_SPEEX_FLOAT_BASE + 3;
 
     return PA_RESAMPLER_INVALID;
 }
 
+static pa_bool_t on_left(pa_channel_position_t p) {
+
+    return
+        p == PA_CHANNEL_POSITION_FRONT_LEFT ||
+        p == PA_CHANNEL_POSITION_REAR_LEFT ||
+        p == PA_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER ||
+        p == PA_CHANNEL_POSITION_SIDE_LEFT ||
+        p == PA_CHANNEL_POSITION_TOP_FRONT_LEFT ||
+        p == PA_CHANNEL_POSITION_TOP_REAR_LEFT;
+}
+
+static pa_bool_t on_right(pa_channel_position_t p) {
+
+    return
+        p == PA_CHANNEL_POSITION_FRONT_RIGHT ||
+        p == PA_CHANNEL_POSITION_REAR_RIGHT ||
+        p == PA_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER ||
+        p == PA_CHANNEL_POSITION_SIDE_RIGHT ||
+        p == PA_CHANNEL_POSITION_TOP_FRONT_RIGHT ||
+        p == PA_CHANNEL_POSITION_TOP_REAR_RIGHT;
+}
+
+static pa_bool_t on_center(pa_channel_position_t p) {
+
+    return
+        p == PA_CHANNEL_POSITION_FRONT_CENTER ||
+        p == PA_CHANNEL_POSITION_REAR_CENTER ||
+        p == PA_CHANNEL_POSITION_TOP_CENTER ||
+        p == PA_CHANNEL_POSITION_TOP_FRONT_CENTER ||
+        p == PA_CHANNEL_POSITION_TOP_REAR_CENTER;
+}
+
+static pa_bool_t on_lfe(pa_channel_position_t p) {
+    return
+        p == PA_CHANNEL_POSITION_LFE;
+}
+
 static void calc_map_table(pa_resampler *r) {
-    unsigned oc;
-    
+    unsigned oc, ic;
+    pa_bool_t ic_connected[PA_CHANNELS_MAX];
+    pa_bool_t remix;
+    pa_strbuf *s;
+    char *t;
+
     pa_assert(r);
 
-    if (!(r->map_required = (r->i_ss.channels != r->o_ss.channels || !pa_channel_map_equal(&r->i_cm, &r->o_cm))))
+    if (!(r->map_required = (r->i_ss.channels != r->o_ss.channels || (!(r->flags & PA_RESAMPLER_NO_REMAP) && !pa_channel_map_equal(&r->i_cm, &r->o_cm)))))
         return;
 
+    memset(r->map_table, 0, sizeof(r->map_table));
+    memset(ic_connected, 0, sizeof(ic_connected));
+    remix = (r->flags & (PA_RESAMPLER_NO_REMAP|PA_RESAMPLER_NO_REMIX)) == 0;
+
     for (oc = 0; oc < r->o_ss.channels; oc++) {
-        unsigned ic, i = 0;
+        pa_bool_t oc_connected = FALSE;
+        pa_channel_position_t b = r->o_cm.map[oc];
+
+        for (ic = 0; ic < r->i_ss.channels; ic++) {
+            pa_channel_position_t a = r->i_cm.map[ic];
+
+            if (r->flags & PA_RESAMPLER_NO_REMAP) {
+                /* We shall not do any remapping. Hence, just check by index */
+
+                if (ic == oc)
+                    r->map_table[oc][ic] = 1.0;
+
+                continue;
+            }
+
+            if (r->flags & PA_RESAMPLER_NO_REMIX) {
+                /* We shall not do any remixing. Hence, just check by name */
+
+                if (a == b)
+                    r->map_table[oc][ic] = 1.0;
+
+                continue;
+            }
+
+            pa_assert(remix);
+
+            /* OK, we shall do the full monty: upmixing and
+             * downmixing. Our algorithm is relatively simple, does
+             * not do spacialization, delay elements or apply lowpass
+             * filters for LFE. Patches are always welcome,
+             * though. Oh, and it doesn't do any matrix
+             * decoding. (Which probably wouldn't make any sense
+             * anyway.)
+             *
+             * This code is not idempotent: downmixing an upmixed
+             * stereo stream is not identical to the original. The
+             * volume will not match, and the two channels will be a
+             * linear combination of both.
+             *
+             * This is losely based on random suggestions found on the
+             * Internet, such as this:
+             * http://www.halfgaar.net/surround-sound-in-linux and the
+             * alsa upmix plugin.
+             *
+             * The algorithm works basically like this:
+             *
+             * 1) Connect all channels with matching names.
+             *
+             * 2) Mono Handling:
+             *    S:Mono: Copy into all D:channels
+             *    D:Mono: Copy in all S:channels
+             *
+             * 3) Mix D:Left, D:Right:
+             *    D:Left: If not connected, avg all S:Left
+             *    D:Right: If not connected, avg all S:Right
+             *
+             * 4) Mix D:Center
+             *       If not connected, avg all S:Center
+             *       If still not connected, avg all S:Left, S:Right
+             *
+             * 5) Mix D:LFE
+             *       If not connected, avg all S:*
+             *
+             * 6) Make sure S:Left/S:Right is used: S:Left/S:Right: If
+             *    not connected, mix into all D:left and all D:right
+             *    channels. Gain is 0.1, the current left and right
+             *    should be multiplied by 0.9.
+             *
+             * 7) Make sure S:Center, S:LFE is used:
+             *
+             *    S:Center, S:LFE: If not connected, mix into all
+             *    D:left, all D:right, all D:center channels, gain is
+             *    0.375. The current (as result of 1..6) factors
+             *    should be multiplied by 0.75. (Alt. suggestion: 0.25
+             *    vs. 0.5)
+             *
+             * S: and D: shall relate to the source resp. destination channels.
+             *
+             * Rationale: 1, 2 are probably obvious. For 3: this
+             * copies front to rear if needed. For 4: we try to find
+             * some suitable C source for C, if we don't find any, we
+             * avg L and R. For 5: LFE is mixed from all channels. For
+             * 6: the rear channels should not be dropped entirely,
+             * however have only minimal impact. For 7: movies usually
+             * encode speech on the center channel. Thus we have to
+             * make sure this channel is distributed to L and R if not
+             * available in the output. Also, LFE is used to achieve a
+             * greater dynamic range, and thus we should try to do our
+             * best to pass it to L+R.
+             */
+
+            if (a == b || a == PA_CHANNEL_POSITION_MONO || b == PA_CHANNEL_POSITION_MONO) {
+                r->map_table[oc][ic] = 1.0;
+
+                oc_connected = TRUE;
+                ic_connected[ic] = TRUE;
+            }
+        }
+
+        if (!oc_connected && remix) {
+            /* OK, we shall remix */
+
+            if (on_left(b)) {
+                unsigned n = 0;
+
+                /* We are not connected and on the left side, let's
+                 * average all left side input channels. */
+
+                for (ic = 0; ic < r->i_ss.channels; ic++)
+                    if (on_left(r->i_cm.map[ic]))
+                        n++;
+
+                if (n > 0)
+                    for (ic = 0; ic < r->i_ss.channels; ic++)
+                        if (on_left(r->i_cm.map[ic])) {
+                            r->map_table[oc][ic] = 1.0f / (float) n;
+                            ic_connected[ic] = TRUE;
+                        }
+
+                /* We ignore the case where there is no left input
+                 * channel. Something is really wrong in this case
+                 * anyway. */
+
+            } else if (on_right(b)) {
+                unsigned n = 0;
+
+                /* We are not connected and on the right side, let's
+                 * average all right side input channels. */
+
+                for (ic = 0; ic < r->i_ss.channels; ic++)
+                    if (on_right(r->i_cm.map[ic]))
+                        n++;
+
+                if (n > 0)
+                    for (ic = 0; ic < r->i_ss.channels; ic++)
+                        if (on_right(r->i_cm.map[ic])) {
+                            r->map_table[oc][ic] = 1.0f / (float) n;
+                            ic_connected[ic] = TRUE;
+                        }
+
+                /* We ignore the case where there is no right input
+                 * channel. Something is really wrong in this case
+                 * anyway. */
+
+            } else if (on_center(b)) {
+                unsigned n = 0;
+
+                /* We are not connected and at the center. Let's
+                 * average all center input channels. */
+
+                for (ic = 0; ic < r->i_ss.channels; ic++)
+                    if (on_center(r->i_cm.map[ic]))
+                        n++;
+
+                if (n > 0) {
+                    for (ic = 0; ic < r->i_ss.channels; ic++)
+                        if (on_center(r->i_cm.map[ic])) {
+                            r->map_table[oc][ic] = 1.0f / (float) n;
+                            ic_connected[ic] = TRUE;
+                        }
+                } else {
+
+                    /* Hmm, no center channel around, let's synthesize
+                     * it by mixing L and R.*/
+
+                    n = 0;
+
+                    for (ic = 0; ic < r->i_ss.channels; ic++)
+                        if (on_left(r->i_cm.map[ic]) || on_right(r->i_cm.map[ic]))
+                            n++;
+
+                    if (n > 0)
+                        for (ic = 0; ic < r->i_ss.channels; ic++)
+                            if (on_left(r->i_cm.map[ic]) || on_right(r->i_cm.map[ic])) {
+                                r->map_table[oc][ic] = 1.0f / (float) n;
+                                ic_connected[ic] = TRUE;
+                            }
+
+                    /* We ignore the case where there is not even a
+                     * left or right input channel. Something is
+                     * really wrong in this case anyway. */
+                }
+
+            } else if (on_lfe(b)) {
+
+                /* We are not connected and an LFE. Let's average all
+                 * channels for LFE. */
+
+                for (ic = 0; ic < r->i_ss.channels; ic++) {
+
+                    if (!(r->flags & PA_RESAMPLER_NO_LFE))
+                        r->map_table[oc][ic] = 1.0f / (float) r->i_ss.channels;
+                    else
+                        r->map_table[oc][ic] = 0;
+
+                    /* Please note that a channel connected to LFE
+                     * doesn't really count as connected. */
+                }
+            }
+        }
+    }
+
+    if (remix) {
+        unsigned
+            ic_unconnected_left = 0,
+            ic_unconnected_right = 0,
+            ic_unconnected_center = 0,
+            ic_unconnected_lfe = 0;
 
         for (ic = 0; ic < r->i_ss.channels; ic++) {
-            pa_channel_position_t a, b;
+            pa_channel_position_t a = r->i_cm.map[ic];
+
+            if (ic_connected[ic])
+                continue;
+
+            if (on_left(a))
+                ic_unconnected_left++;
+            else if (on_right(a))
+                ic_unconnected_right++;
+            else if (on_center(a))
+                ic_unconnected_center++;
+            else if (on_lfe(a))
+                ic_unconnected_lfe++;
+        }
+
+        if (ic_unconnected_left > 0) {
+
+            /* OK, so there are unconnected input channels on the
+             * left. Let's multiply all already connected channels on
+             * the left side by .9 and add in our averaged unconnected
+             * channels multplied by .1 */
+
+            for (oc = 0; oc < r->o_ss.channels; oc++) {
+
+                if (!on_left(r->o_cm.map[oc]))
+                    continue;
+
+                for (ic = 0; ic < r->i_ss.channels; ic++) {
+
+                    if (ic_connected[ic]) {
+                        r->map_table[oc][ic] *= .9f;
+                        continue;
+                    }
+
+                    if (on_left(r->i_cm.map[ic]))
+                        r->map_table[oc][ic] = .1f / (float) ic_unconnected_left;
+                }
+            }
+        }
+
+        if (ic_unconnected_right > 0) {
+
+            /* OK, so there are unconnected input channels on the
+             * right. Let's multiply all already connected channels on
+             * the right side by .9 and add in our averaged unconnected
+             * channels multplied by .1 */
+
+            for (oc = 0; oc < r->o_ss.channels; oc++) {
+
+                if (!on_right(r->o_cm.map[oc]))
+                    continue;
+
+                for (ic = 0; ic < r->i_ss.channels; ic++) {
+
+                    if (ic_connected[ic]) {
+                        r->map_table[oc][ic] *= .9f;
+                        continue;
+                    }
+
+                    if (on_right(r->i_cm.map[ic]))
+                        r->map_table[oc][ic] = .1f / (float) ic_unconnected_right;
+                }
+            }
+        }
+
+        if (ic_unconnected_center > 0) {
+            pa_bool_t mixed_in = FALSE;
+
+            /* OK, so there are unconnected input channels on the
+             * center. Let's multiply all already connected channels on
+             * the center side by .9 and add in our averaged unconnected
+             * channels multplied by .1 */
+
+            for (oc = 0; oc < r->o_ss.channels; oc++) {
+
+                if (!on_center(r->o_cm.map[oc]))
+                    continue;
+
+                for (ic = 0; ic < r->i_ss.channels; ic++)  {
+
+                    if (ic_connected[ic]) {
+                        r->map_table[oc][ic] *= .9f;
+                        continue;
+                    }
+
+                    if (on_center(r->i_cm.map[ic])) {
+                        r->map_table[oc][ic] = .1f / (float) ic_unconnected_center;
+                        mixed_in = TRUE;
+                    }
+                }
+            }
+
+            if (!mixed_in) {
+
+                /* Hmm, as it appears there was no center channel we
+                   could mix our center channel in. In this case, mix
+                   it into left and right. Using .375 and 0.75 as
+                   factors. */
+
+                for (oc = 0; oc < r->o_ss.channels; oc++) {
+
+                    if (!on_left(r->o_cm.map[oc]) && !on_right(r->o_cm.map[oc]))
+                        continue;
+
+                    for (ic = 0; ic < r->i_ss.channels; ic++)  {
+
+                        if (ic_connected[ic]) {
+                            r->map_table[oc][ic] *= .75f;
+                            continue;
+                        }
 
-            a = r->i_cm.map[ic];
-            b = r->o_cm.map[oc];
+                        if (on_center(r->i_cm.map[ic]))
+                            r->map_table[oc][ic] = .375f / (float) ic_unconnected_center;
+                    }
+                }
+            }
+        }
+
+        if (ic_unconnected_lfe > 0 && !(r->flags & PA_RESAMPLER_NO_LFE)) {
+
+            /* OK, so there is an unconnected LFE channel. Let's mix
+             * it into all channels, with factor 0.375 */
+
+            for (ic = 0; ic < r->i_ss.channels; ic++)  {
 
-            if (a == b ||
-                (a == PA_CHANNEL_POSITION_MONO && b == PA_CHANNEL_POSITION_LEFT) ||
-                (a == PA_CHANNEL_POSITION_MONO && b == PA_CHANNEL_POSITION_RIGHT) ||
-                (a == PA_CHANNEL_POSITION_LEFT && b == PA_CHANNEL_POSITION_MONO) ||
-                (a == PA_CHANNEL_POSITION_RIGHT && b == PA_CHANNEL_POSITION_MONO))
+                if (!on_lfe(r->i_cm.map[ic]))
+                    continue;
 
-                r->map_table[oc][i++] = ic;
+                for (oc = 0; oc < r->o_ss.channels; oc++)
+                    r->map_table[oc][ic] = 0.375f / (float) ic_unconnected_lfe;
+            }
         }
+    }
+
+
+    s = pa_strbuf_new();
+
+    pa_strbuf_printf(s, "     ");
+    for (ic = 0; ic < r->i_ss.channels; ic++)
+        pa_strbuf_printf(s, "  I%02u ", ic);
+    pa_strbuf_puts(s, "\n    +");
 
-        /* Add an end marker */
-        if (i < PA_CHANNELS_MAX)
-            r->map_table[oc][i] = -1;
+    for (ic = 0; ic < r->i_ss.channels; ic++)
+        pa_strbuf_printf(s, "------");
+    pa_strbuf_puts(s, "\n");
+
+    for (oc = 0; oc < r->o_ss.channels; oc++) {
+        pa_strbuf_printf(s, "O%02u |", oc);
+
+        for (ic = 0; ic < r->i_ss.channels; ic++)
+            pa_strbuf_printf(s, " %1.3f", r->map_table[oc][ic]);
+
+        pa_strbuf_puts(s, "\n");
     }
+
+    pa_log_debug("Channel matrix:\n%s", t = pa_strbuf_tostring_free(s));
+    pa_xfree(t);
 }
 
 static pa_memchunk* convert_to_work_format(pa_resampler *r, pa_memchunk *input) {
@@ -423,11 +909,11 @@ static pa_memchunk* convert_to_work_format(pa_resampler *r, pa_memchunk *input)
     if (!r->to_work_format_func || !input->length)
         return input;
 
-    n_samples = (input->length / r->i_fz) * r->i_ss.channels;
+    n_samples = (unsigned) ((input->length / r->i_fz) * r->i_ss.channels);
 
     r->buf1.index = 0;
     r->buf1.length = r->w_sz * n_samples;
-    
+
     if (!r->buf1.memblock || r->buf1_samples < n_samples) {
         if (r->buf1.memblock)
             pa_memblock_unref(r->buf1.memblock);
@@ -447,6 +933,36 @@ static pa_memchunk* convert_to_work_format(pa_resampler *r, pa_memchunk *input)
     return &r->buf1;
 }
 
+static void vectoradd_s16_with_fraction(
+        int16_t *d, int dstr,
+        const int16_t *s1, int sstr1,
+        const int16_t *s2, int sstr2,
+        int n,
+        float s3, float s4) {
+
+    int32_t i3, i4;
+
+    i3 = (int32_t) (s3 * 0x10000);
+    i4 = (int32_t) (s4 * 0x10000);
+
+    for (; n > 0; n--) {
+        int32_t a, b;
+
+        a = *s1;
+        b = *s2;
+
+        a = (a * i3) / 0x10000;
+        b = (b * i4) / 0x10000;
+
+        *d = (int16_t) (a + b);
+
+        s1 = (const int16_t*) ((const uint8_t*) s1 + sstr1);
+        s2 = (const int16_t*) ((const uint8_t*) s2 + sstr2);
+        d = (int16_t*) ((uint8_t*) d + dstr);
+
+    }
+}
+
 static pa_memchunk *remap_channels(pa_resampler *r, pa_memchunk *input) {
     unsigned in_n_samples, out_n_samples, n_frames;
     int i_skip, o_skip;
@@ -462,13 +978,13 @@ static pa_memchunk *remap_channels(pa_resampler *r, pa_memchunk *input) {
     if (!r->map_required || !input->length)
         return input;
 
-    in_n_samples = input->length / r->w_sz;
+    in_n_samples = (unsigned) (input->length / r->w_sz);
     n_frames = in_n_samples / r->i_ss.channels;
     out_n_samples = n_frames * r->o_ss.channels;
 
     r->buf2.index = 0;
     r->buf2.length = r->w_sz * out_n_samples;
-    
+
     if (!r->buf2.memblock || r->buf2_samples < out_n_samples) {
         if (r->buf2.memblock)
             pa_memblock_unref(r->buf2.memblock);
@@ -482,23 +998,28 @@ static pa_memchunk *remap_channels(pa_resampler *r, pa_memchunk *input) {
 
     memset(dst, 0, r->buf2.length);
 
-    o_skip = r->w_sz * r->o_ss.channels;
-    i_skip = r->w_sz * r->i_ss.channels;
+    o_skip = (int) (r->w_sz * r->o_ss.channels);
+    i_skip = (int) (r->w_sz * r->i_ss.channels);
 
     switch (r->work_format) {
         case PA_SAMPLE_FLOAT32NE:
-            
+
             for (oc = 0; oc < r->o_ss.channels; oc++) {
-                unsigned i;
+                unsigned ic;
                 static const float one = 1.0;
-                
-                for (i = 0; i < PA_CHANNELS_MAX && r->map_table[oc][i] >= 0; i++)
+
+                for (ic = 0; ic < r->i_ss.channels; ic++) {
+
+                    if (r->map_table[oc][ic] <= 0.0)
+                        continue;
+
                     oil_vectoradd_f32(
                             (float*) dst + oc, o_skip,
                             (float*) dst + oc, o_skip,
-                            (float*) src + r->map_table[oc][i], i_skip,
-                            n_frames,
-                            &one, &one);
+                            (float*) src + ic, i_skip,
+                            (int) n_frames,
+                            &one, &r->map_table[oc][ic]);
+                }
             }
 
             break;
@@ -506,16 +1027,32 @@ static pa_memchunk *remap_channels(pa_resampler *r, pa_memchunk *input) {
         case PA_SAMPLE_S16NE:
 
             for (oc = 0; oc < r->o_ss.channels; oc++) {
-                unsigned i;
-                static const int16_t one = 1;
-                
-                for (i = 0; i < PA_CHANNELS_MAX && r->map_table[oc][i] >= 0; i++)
-                    oil_vectoradd_s16(
-                            (int16_t*) dst + oc, o_skip,
-                            (int16_t*) dst + oc, o_skip,
-                            (int16_t*) src + r->map_table[oc][i], i_skip,
-                            n_frames,
-                            &one, &one);
+                unsigned ic;
+
+                for (ic = 0; ic < r->i_ss.channels; ic++) {
+
+                    if (r->map_table[oc][ic] <= 0.0)
+                        continue;
+
+                    if (r->map_table[oc][ic] >= 1.0) {
+                        static const int16_t one = 1;
+
+                        oil_vectoradd_s16(
+                                (int16_t*) dst + oc, o_skip,
+                                (int16_t*) dst + oc, o_skip,
+                                (int16_t*) src + ic, i_skip,
+                                (int) n_frames,
+                                &one, &one);
+
+                    } else
+
+                        vectoradd_s16_with_fraction(
+                                (int16_t*) dst + oc, o_skip,
+                                (int16_t*) dst + oc, o_skip,
+                                (int16_t*) src + ic, i_skip,
+                                (int) n_frames,
+                                1.0f, r->map_table[oc][ic]);
+                }
             }
 
             break;
@@ -544,15 +1081,15 @@ static pa_memchunk *resample(pa_resampler *r, pa_memchunk *input) {
     if (!r->impl_resample || !input->length)
         return input;
 
-    in_n_samples = input->length / r->w_sz;
-    in_n_frames = in_n_samples / r->o_ss.channels;
+    in_n_samples = (unsigned) (input->length / r->w_sz);
+    in_n_frames = (unsigned) (in_n_samples / r->o_ss.channels);
 
-    out_n_frames = ((in_n_frames*r->o_ss.rate)/r->i_ss.rate)+1024;
+    out_n_frames = ((in_n_frames*r->o_ss.rate)/r->i_ss.rate)+EXTRA_FRAMES;
     out_n_samples = out_n_frames * r->o_ss.channels;
 
     r->buf3.index = 0;
     r->buf3.length = r->w_sz * out_n_samples;
-    
+
     if (!r->buf3.memblock || r->buf3_samples < out_n_samples) {
         if (r->buf3.memblock)
             pa_memblock_unref(r->buf3.memblock);
@@ -563,7 +1100,7 @@ static pa_memchunk *resample(pa_resampler *r, pa_memchunk *input) {
 
     r->impl_resample(r, input, in_n_frames, &r->buf3, &out_n_frames);
     r->buf3.length = out_n_frames * r->w_sz * r->o_ss.channels;
-    
+
     return &r->buf3;
 }
 
@@ -579,12 +1116,12 @@ static pa_memchunk *convert_from_work_format(pa_resampler *r, pa_memchunk *input
     if (!r->from_work_format_func || !input->length)
         return input;
 
-    n_samples = input->length / r->w_sz;
-    n_frames =  n_samples / r->o_ss.channels;
+    n_samples = (unsigned) (input->length / r->w_sz);
+    n_frames = n_samples / r->o_ss.channels;
 
     r->buf4.index = 0;
     r->buf4.length = r->o_fz * n_frames;
-        
+
     if (!r->buf4.memblock || r->buf4_samples < n_samples) {
         if (r->buf4.memblock)
             pa_memblock_unref(r->buf4.memblock);
@@ -622,7 +1159,7 @@ void pa_resampler_run(pa_resampler *r, const pa_memchunk *in, pa_memchunk *out)
     if (buf->length) {
         buf = convert_from_work_format(r, buf);
         *out = *buf;
-        
+
         if (buf == in)
             pa_memblock_ref(buf->memblock);
         else
@@ -636,19 +1173,19 @@ void pa_resampler_run(pa_resampler *r, const pa_memchunk *in, pa_memchunk *out)
 #ifdef HAVE_LIBSAMPLERATE
 static void libsamplerate_resample(pa_resampler *r, const pa_memchunk *input, unsigned in_n_frames, pa_memchunk *output, unsigned *out_n_frames) {
     SRC_DATA data;
-    
+
     pa_assert(r);
     pa_assert(input);
     pa_assert(output);
     pa_assert(out_n_frames);
-    
+
     memset(&data, 0, sizeof(data));
-    
+
     data.data_in = (float*) ((uint8_t*) pa_memblock_acquire(input->memblock) + input->index);
-    data.input_frames = in_n_frames;
+    data.input_frames = (long int) in_n_frames;
 
     data.data_out = (float*) ((uint8_t*) pa_memblock_acquire(output->memblock) + output->index);
-    data.output_frames = *out_n_frames;
+    data.output_frames = (long int) *out_n_frames;
 
     data.src_ratio = (double) r->o_ss.rate / r->i_ss.rate;
     data.end_of_input = 0;
@@ -659,7 +1196,7 @@ static void libsamplerate_resample(pa_resampler *r, const pa_memchunk *input, un
     pa_memblock_release(input->memblock);
     pa_memblock_release(output->memblock);
 
-    *out_n_frames = data.output_frames_gen;
+    *out_n_frames = (unsigned) data.output_frames_gen;
 }
 
 static void libsamplerate_update_rates(pa_resampler *r) {
@@ -668,24 +1205,31 @@ static void libsamplerate_update_rates(pa_resampler *r) {
     pa_assert_se(src_set_ratio(r->src.state, (double) r->o_ss.rate / r->i_ss.rate) == 0);
 }
 
+static void libsamplerate_reset(pa_resampler *r) {
+    pa_assert(r);
+
+    pa_assert_se(src_reset(r->src.state) == 0);
+}
+
 static void libsamplerate_free(pa_resampler *r) {
     pa_assert(r);
-    
+
     if (r->src.state)
         src_delete(r->src.state);
 }
 
 static int libsamplerate_init(pa_resampler *r) {
     int err;
-    
+
     pa_assert(r);
-    
-    if (!(r->src.state = src_new(r->resample_method, r->o_ss.channels, &err)))
+
+    if (!(r->src.state = src_new(r->method, r->o_ss.channels, &err)))
         return -1;
 
     r->impl_free = libsamplerate_free;
     r->impl_update_rates = libsamplerate_update_rates;
     r->impl_resample = libsamplerate_resample;
+    r->impl_reset = libsamplerate_reset;
 
     return 0;
 }
@@ -701,11 +1245,11 @@ static void speex_resample_float(pa_resampler *r, const pa_memchunk *input, unsi
     pa_assert(input);
     pa_assert(output);
     pa_assert(out_n_frames);
-    
+
     in = (float*) ((uint8_t*) pa_memblock_acquire(input->memblock) + input->index);
     out = (float*) ((uint8_t*) pa_memblock_acquire(output->memblock) + output->index);
 
-    pa_assert_se(paspfl_resampler_process_interleaved_float(r->speex.state, in, &inf, out, &outf) == 0);
+    pa_assert_se(speex_resampler_process_interleaved_float(r->speex.state, in, &inf, out, &outf) == 0);
 
     pa_memblock_release(input->memblock);
     pa_memblock_release(output->memblock);
@@ -722,11 +1266,11 @@ static void speex_resample_int(pa_resampler *r, const pa_memchunk *input, unsign
     pa_assert(input);
     pa_assert(output);
     pa_assert(out_n_frames);
-    
+
     in = (int16_t*) ((uint8_t*) pa_memblock_acquire(input->memblock) + input->index);
     out = (int16_t*) ((uint8_t*) pa_memblock_acquire(output->memblock) + output->index);
 
-    pa_assert_se(paspfx_resampler_process_interleaved_int(r->speex.state, in, &inf, out, &outf) == 0);
+    pa_assert_se(speex_resampler_process_interleaved_int(r->speex.state, in, &inf, out, &outf) == 0);
 
     pa_memblock_release(input->memblock);
     pa_memblock_release(output->memblock);
@@ -738,57 +1282,50 @@ static void speex_resample_int(pa_resampler *r, const pa_memchunk *input, unsign
 static void speex_update_rates(pa_resampler *r) {
     pa_assert(r);
 
-    if (r->resample_method >= PA_RESAMPLER_SPEEX_FIXED_BASE && r->resample_method <= PA_RESAMPLER_SPEEX_FIXED_MAX) 
-        pa_assert_se(paspfx_resampler_set_rate(r->speex.state, r->i_ss.rate, r->o_ss.rate) == 0);
-    else {
-        pa_assert(r->resample_method >= PA_RESAMPLER_SPEEX_FLOAT_BASE && r->resample_method <= PA_RESAMPLER_SPEEX_FLOAT_MAX);
-        pa_assert_se(paspfl_resampler_set_rate(r->speex.state, r->i_ss.rate, r->o_ss.rate) == 0);
-    }
+    pa_assert_se(speex_resampler_set_rate(r->speex.state, r->i_ss.rate, r->o_ss.rate) == 0);
+}
+
+static void speex_reset(pa_resampler *r) {
+    pa_assert(r);
+
+    pa_assert_se(speex_resampler_reset_mem(r->speex.state) == 0);
 }
 
 static void speex_free(pa_resampler *r) {
     pa_assert(r);
-    
+
     if (!r->speex.state)
         return;
-    
-    if (r->resample_method >= PA_RESAMPLER_SPEEX_FIXED_BASE && r->resample_method <= PA_RESAMPLER_SPEEX_FIXED_MAX) 
-        paspfx_resampler_destroy(r->speex.state);
-    else {
-        pa_assert(r->resample_method >= PA_RESAMPLER_SPEEX_FLOAT_BASE && r->resample_method <= PA_RESAMPLER_SPEEX_FLOAT_MAX);
-        paspfl_resampler_destroy(r->speex.state);
-    }
+
+    speex_resampler_destroy(r->speex.state);
 }
 
 static int speex_init(pa_resampler *r) {
     int q, err;
-    
+
     pa_assert(r);
 
     r->impl_free = speex_free;
     r->impl_update_rates = speex_update_rates;
-    
-    if (r->resample_method >= PA_RESAMPLER_SPEEX_FIXED_BASE && r->resample_method <= PA_RESAMPLER_SPEEX_FIXED_MAX) {
-        q = r->resample_method - PA_RESAMPLER_SPEEX_FIXED_BASE;
+    r->impl_reset = speex_reset;
 
-        pa_log_info("Choosing speex quality setting %i.", q);
-        
-        if (!(r->speex.state = paspfx_resampler_init(r->o_ss.channels, r->i_ss.rate, r->o_ss.rate, q, &err)))
-            return -1;
+    if (r->method >= PA_RESAMPLER_SPEEX_FIXED_BASE && r->method <= PA_RESAMPLER_SPEEX_FIXED_MAX) {
 
+        q = r->method - PA_RESAMPLER_SPEEX_FIXED_BASE;
         r->impl_resample = speex_resample_int;
-    } else {
-        pa_assert(r->resample_method >= PA_RESAMPLER_SPEEX_FLOAT_BASE && r->resample_method <= PA_RESAMPLER_SPEEX_FLOAT_MAX);
-        q = r->resample_method - PA_RESAMPLER_SPEEX_FLOAT_BASE;
 
-        pa_log_info("Choosing speex quality setting %i.", q);
-        
-        if (!(r->speex.state = paspfl_resampler_init(r->o_ss.channels, r->i_ss.rate, r->o_ss.rate, q, &err)))
-            return -1;
+    } else {
+        pa_assert(r->method >= PA_RESAMPLER_SPEEX_FLOAT_BASE && r->method <= PA_RESAMPLER_SPEEX_FLOAT_MAX);
 
+        q = r->method - PA_RESAMPLER_SPEEX_FLOAT_BASE;
         r->impl_resample = speex_resample_float;
     }
 
+    pa_log_info("Choosing speex quality setting %i.", q);
+
+    if (!(r->speex.state = speex_resampler_init(r->o_ss.channels, r->i_ss.rate, r->o_ss.rate, q, &err)))
+        return -1;
+
     return 0;
 }
 
@@ -798,35 +1335,35 @@ static void trivial_resample(pa_resampler *r, const pa_memchunk *input, unsigned
     size_t fz;
     unsigned o_index;
     void *src, *dst;
-    
+
     pa_assert(r);
     pa_assert(input);
     pa_assert(output);
     pa_assert(out_n_frames);
 
     fz = r->w_sz * r->o_ss.channels;
-    
+
     src = (uint8_t*) pa_memblock_acquire(input->memblock) + input->index;
     dst = (uint8_t*) pa_memblock_acquire(output->memblock) + output->index;
-    
+
     for (o_index = 0;; o_index++, r->trivial.o_counter++) {
         unsigned j;
-        
+
         j = ((r->trivial.o_counter * r->i_ss.rate) / r->o_ss.rate);
         j = j > r->trivial.i_counter ? j - r->trivial.i_counter : 0;
-        
+
         if (j >= in_n_frames)
             break;
 
         pa_assert(o_index * fz < pa_memblock_get_length(output->memblock));
-        
+
         oil_memcpy((uint8_t*) dst + fz * o_index,
-                   (uint8_t*) src + fz * j, fz);   
+                   (uint8_t*) src + fz * j, (int) fz);
     }
-    
+
     pa_memblock_release(input->memblock);
     pa_memblock_release(output->memblock);
-    
+
     *out_n_frames = o_index;
 
     r->trivial.i_counter += in_n_frames;
@@ -840,7 +1377,7 @@ static void trivial_resample(pa_resampler *r, const pa_memchunk *input, unsigned
     }
 }
 
-static void trivial_update_rates(pa_resampler *r) {
+static void trivial_update_rates_or_reset(pa_resampler *r) {
     pa_assert(r);
 
     r->trivial.i_counter = 0;
@@ -853,7 +1390,117 @@ static int trivial_init(pa_resampler*r) {
     r->trivial.o_counter = r->trivial.i_counter = 0;
 
     r->impl_resample = trivial_resample;
-    r->impl_update_rates = trivial_update_rates;
+    r->impl_update_rates = trivial_update_rates_or_reset;
+    r->impl_reset = trivial_update_rates_or_reset;
+
+    return 0;
+}
+
+/* Peak finder implementation */
+
+static void peaks_resample(pa_resampler *r, const pa_memchunk *input, unsigned in_n_frames, pa_memchunk *output, unsigned *out_n_frames) {
+    size_t fz;
+    unsigned o_index;
+    void *src, *dst;
+    unsigned start = 0;
+
+    pa_assert(r);
+    pa_assert(input);
+    pa_assert(output);
+    pa_assert(out_n_frames);
+
+    fz = r->w_sz * r->o_ss.channels;
+
+    src = (uint8_t*) pa_memblock_acquire(input->memblock) + input->index;
+    dst = (uint8_t*) pa_memblock_acquire(output->memblock) + output->index;
+
+    for (o_index = 0;; o_index++, r->peaks.o_counter++) {
+        unsigned j;
+
+        j = ((r->peaks.o_counter * r->i_ss.rate) / r->o_ss.rate);
+        j = j > r->peaks.i_counter ? j - r->peaks.i_counter : 0;
+
+        if (j >= in_n_frames)
+            break;
+
+        pa_assert(o_index * fz < pa_memblock_get_length(output->memblock));
+
+        if (r->work_format == PA_SAMPLE_S16NE) {
+            unsigned i, c;
+            int16_t *s = (int16_t*) ((uint8_t*) src + fz * j);
+            int16_t *d = (int16_t*) ((uint8_t*) dst + fz * o_index);
+
+            for (i = start; i <= j; i++)
+                for (c = 0; c < r->o_ss.channels; c++, s++) {
+                    int16_t n;
+
+                    n = (int16_t) (*s < 0 ? -*s : *s);
+
+                    if (n > r->peaks.max_i[c])
+                        r->peaks.max_i[c] = n;
+                }
+
+            for (c = 0; c < r->o_ss.channels; c++, d++) {
+                 *d = r->peaks.max_i[c];
+                 r->peaks.max_i[c] = 0;
+            }
+        } else {
+            unsigned i, c;
+            float *s = (float*) ((uint8_t*) src + fz * j);
+            float *d = (float*) ((uint8_t*) dst + fz * o_index);
+
+            pa_assert(r->work_format == PA_SAMPLE_FLOAT32NE);
+
+            for (i = start; i <= j; i++)
+                for (c = 0; c < r->o_ss.channels; c++, s++) {
+                    float n = fabsf(*s);
+
+                    if (n > r->peaks.max_f[c])
+                        r->peaks.max_f[c] = n;
+                }
+
+            for (c = 0; c < r->o_ss.channels; c++, d++) {
+                *d = r->peaks.max_f[c];
+                r->peaks.max_f[c] = 0;
+            }
+        }
+
+        start = j+1;
+    }
+
+    pa_memblock_release(input->memblock);
+    pa_memblock_release(output->memblock);
+
+    *out_n_frames = o_index;
+
+    r->peaks.i_counter += in_n_frames;
+
+    /* Normalize counters */
+    while (r->peaks.i_counter >= r->i_ss.rate) {
+        pa_assert(r->peaks.o_counter >= r->o_ss.rate);
+
+        r->peaks.i_counter -= r->i_ss.rate;
+        r->peaks.o_counter -= r->o_ss.rate;
+    }
+}
+
+static void peaks_update_rates_or_reset(pa_resampler *r) {
+    pa_assert(r);
+
+    r->peaks.i_counter = 0;
+    r->peaks.o_counter = 0;
+}
+
+static int peaks_init(pa_resampler*r) {
+    pa_assert(r);
+
+    r->peaks.o_counter = r->peaks.i_counter = 0;
+    memset(r->peaks.max_i, 0, sizeof(r->peaks.max_i));
+    memset(r->peaks.max_f, 0, sizeof(r->peaks.max_f));
+
+    r->impl_resample = peaks_resample;
+    r->impl_update_rates = peaks_update_rates_or_reset;
+    r->impl_reset = peaks_update_rates_or_reset;
 
     return 0;
 }
@@ -862,7 +1509,7 @@ static int trivial_init(pa_resampler*r) {
 
 static void ffmpeg_resample(pa_resampler *r, const pa_memchunk *input, unsigned in_n_frames, pa_memchunk *output, unsigned *out_n_frames) {
     unsigned used_frames = 0, c;
-    
+
     pa_assert(r);
     pa_assert(input);
     pa_assert(output);
@@ -880,7 +1527,7 @@ static void ffmpeg_resample(pa_resampler *r, const pa_memchunk *input, unsigned
         p = pa_memblock_acquire(b);
 
         /* Copy the remaining data into it */
-        l = r->ffmpeg.buf[c].length;
+        l = (unsigned) r->ffmpeg.buf[c].length;
         if (r->ffmpeg.buf[c].memblock) {
             t = (int16_t*) ((uint8_t*) pa_memblock_acquire(r->ffmpeg.buf[c].memblock) + r->ffmpeg.buf[c].index);
             memcpy(p, t, l);
@@ -900,18 +1547,18 @@ static void ffmpeg_resample(pa_resampler *r, const pa_memchunk *input, unsigned
         pa_memblock_release(input->memblock);
 
         /* Calculate the resulting number of frames */
-        in = in_n_frames + l / sizeof(int16_t);
+        in = (unsigned) in_n_frames + l / (unsigned) sizeof(int16_t);
 
         /* Allocate buffer for the result */
         w = pa_memblock_new(r->mempool, *out_n_frames * sizeof(int16_t));
         q = pa_memblock_acquire(w);
 
         /* Now, resample */
-        used_frames = av_resample(r->ffmpeg.state,
-                                  q, p,
-                                  &consumed_frames,
-                                  in, *out_n_frames,
-                                  c >= (unsigned) r->o_ss.channels-1);
+        used_frames = (unsigned) av_resample(r->ffmpeg.state,
+                                             q, p,
+                                             &consumed_frames,
+                                             (int) in, (int) *out_n_frames,
+                                             c >= (unsigned) (r->o_ss.channels-1));
 
         pa_memblock_release(b);
 
@@ -919,8 +1566,8 @@ static void ffmpeg_resample(pa_resampler *r, const pa_memchunk *input, unsigned
         pa_assert(consumed_frames <= (int) in);
         if (consumed_frames < (int) in) {
             r->ffmpeg.buf[c].memblock = b;
-            r->ffmpeg.buf[c].index = consumed_frames * sizeof(int16_t);
-            r->ffmpeg.buf[c].length = (in - consumed_frames) * sizeof(int16_t);
+            r->ffmpeg.buf[c].index = (size_t) consumed_frames * sizeof(int16_t);
+            r->ffmpeg.buf[c].length = (size_t) (in - (unsigned) consumed_frames) * sizeof(int16_t);
         } else
             pa_memblock_unref(b);
 
@@ -941,9 +1588,9 @@ static void ffmpeg_resample(pa_resampler *r, const pa_memchunk *input, unsigned
 
 static void ffmpeg_free(pa_resampler *r) {
     unsigned c;
-    
+
     pa_assert(r);
-    
+
     if (r->ffmpeg.state)
         av_resample_close(r->ffmpeg.state);
 
@@ -954,22 +1601,32 @@ static void ffmpeg_free(pa_resampler *r) {
 
 static int ffmpeg_init(pa_resampler *r) {
     unsigned c;
-    
+
     pa_assert(r);
 
     /* We could probably implement different quality levels by
      * adjusting the filter parameters here. However, ffmpeg
      * internally only uses these hardcoded values, so let's use them
      * here for now as well until ffmpeg makes this configurable. */
-    
-    if (!(r->ffmpeg.state = av_resample_init(r->o_ss.rate, r->i_ss.rate, 16, 10, 0, 0.8)))
+
+    if (!(r->ffmpeg.state = av_resample_init((int) r->o_ss.rate, (int) r->i_ss.rate, 16, 10, 0, 0.8)))
         return -1;
 
     r->impl_free = ffmpeg_free;
     r->impl_resample = ffmpeg_resample;
 
-    for (c = 0; c < PA_ELEMENTSOF(r->ffmpeg.buf); c++) 
+    for (c = 0; c < PA_ELEMENTSOF(r->ffmpeg.buf); c++)
         pa_memchunk_reset(&r->ffmpeg.buf[c]);
 
     return 0;
 }
+
+/*** copy (noop) implementation ***/
+
+static int copy_init(pa_resampler *r) {
+    pa_assert(r);
+
+    pa_assert(r->o_ss.rate == r->i_ss.rate);
+
+    return 0;
+}