audio: allow specifying pitch correction filter

DOCS/man/options.rst

@@ -1846,10 +1846,20 @@ Video
 Audio
 -----
 
-``--audio-pitch-correction=<yes|no>``
-    If this is enabled (default), playing with a speed different from normal
-    automatically inserts the ``scaletempo2`` audio filter. For details, see
-    audio filter section.
+``--audio-pitch-correction=<no|<filter>|yes>``
+    If this is set to "yes" (default), playing with a speed different from
+    normal automatically inserts the ``scaletempo2`` audio filter. Aditionally,
+    a ``<filter>`` can be one of the following:
+
+    :scaletempo:  The original pitch correction filter used in mpv, similar to
+                  and generally worse than scaletempo2 in every use case.
+    :scaletempo2: This algorithm is ported from chromium. Also aliased to "yes"
+                  (Default)
+    :rubberband:  High quality pitch correction with librubberband. Uses more
+                  CPU cycles than the others, but often achieves higher quality
+                  with its R3 engine.
+
+    For details, see audio filter section.
 
 ``--audio-device=<name>``
     Use the given audio device. This consists of the audio output name, e.g.

filters/f_auto_filters.c

@@ -310,6 +310,7 @@ struct aspeed_priv {
     struct mp_subfilter sub;
     double cur_speed, cur_speed_drop;
     int current_filter;
+    const char *name;
 };
 
 static void aspeed_process(struct mp_filter *f)
@@ -340,9 +341,9 @@ static void aspeed_process(struct mp_filter *f)
 
         if (req_filter) {
             if (req_filter == 1) {
-                MP_VERBOSE(f, "adding scaletempo2\n");
+                MP_VERBOSE(f, "adding %s\n", p->name);
                 p->sub.filter = mp_create_user_filter(f, MP_OUTPUT_CHAIN_AUDIO,
-                                                      "scaletempo2", NULL);
+                                                      p->name, NULL);
             } else if (req_filter == 2) {
                 MP_VERBOSE(f, "adding drop\n");
                 p->sub.filter = mp_create_user_filter(f, MP_OUTPUT_CHAIN_AUDIO,
@@ -372,6 +373,11 @@ static bool aspeed_command(struct mp_filter *f, struct mp_filter_command *cmd)
 {
     struct aspeed_priv *p = f->priv;
 
+    if (cmd->type == MP_FILTER_COMMAND_TEXT) {
+        p->name = cmd->cmd;
+        return true;
+    }
+
     if (cmd->type == MP_FILTER_COMMAND_SET_SPEED) {
         p->cur_speed = cmd->speed;
         return true;

filters/f_output_chain.c

@@ -478,8 +478,21 @@ static void set_speed_any(struct mp_user_filter **filters, int num_filters,
     }
 }
 
+static void set_speed_params_any(struct mp_user_filter **filters, int num_filters,
+                          int command, const char *name)
+{
+    for (int n = num_filters - 1; n >= 0; n--) {
+        struct mp_filter_command cmd = {
+            .type = command,
+            .cmd = name,
+        };
+        mp_filter_command(filters[n]->f, &cmd);
+    }
+}
+
 void mp_output_chain_set_audio_speed(struct mp_output_chain *c,
-                                     double speed, double resample, double drop)
+                                     double speed, double resample, double drop,
+                                     const char *name)
 {
     struct chain *p = c->f->priv;
 
@@ -491,6 +504,8 @@ void mp_output_chain_set_audio_speed(struct mp_output_chain *c,
     // otherwise use the builtin ones.
     set_speed_any(p->user_filters, p->num_user_filters,
                   MP_FILTER_COMMAND_SET_SPEED, &speed);
+    set_speed_params_any(p->post_filters, p->num_post_filters,
+                         MP_FILTER_COMMAND_TEXT, name);
     set_speed_any(p->post_filters, p->num_post_filters,
                   MP_FILTER_COMMAND_SET_SPEED, &speed);
     set_speed_any(p->user_filters, p->num_user_filters,

filters/f_output_chain.h

@@ -77,8 +77,8 @@ bool mp_output_chain_update_filters(struct mp_output_chain *p,
 
 // Desired audio speed, with resample being strict resampling.
 void mp_output_chain_set_audio_speed(struct mp_output_chain *p,
-                                     double speed, double resample, double drop);
-
+                                     double speed, double resample, double drop,
+                                     const char *name);
 // Total delay incurred by the filter chain, as measured by the recent filtered
 // frames. The intention is that this sums the measured delays for each filter,
 // so if a filter is removed, the caller can estimate how much audio is missing

options/options.c

@@ -595,7 +595,9 @@ static const m_option_t mp_opts[] = {
     {"audio-format", OPT_AUDIOFORMAT(audio_output_format), .flags = UPDATE_AUDIO},
     {"speed", OPT_DOUBLE(playback_speed), M_RANGE(0.01, 100.0)},
 
-    {"audio-pitch-correction", OPT_BOOL(pitch_correction)},
+    {"audio-pitch-correction", OPT_CHOICE(pitch_correction,
+            {"no", 0}, {"yes", 1},
+            {"scaletempo2", 1}, {"rubberband", 2}, {"scaletempo", 3})},
 
     // set a-v distance
     {"audio-delay", OPT_FLOAT(audio_delay)},
@@ -948,7 +950,7 @@ static const struct MPOpts mp_default_opts = {
     .audio_display = 1,
     .audio_output_format = 0,  // AF_FORMAT_UNKNOWN
     .playback_speed = 1.,
-    .pitch_correction = true,
+    .pitch_correction = 1,
     .audiofile_auto = -1,
     .coverart_whitelist = true,
     .osd_bar_visible = true,

options/options.h

@@ -299,7 +299,7 @@ typedef struct MPOpts {
     int audio_output_format;
     int force_srate;
     double playback_speed;
-    bool pitch_correction;
+    int pitch_correction;
     struct m_obj_settings *vf_settings;
     struct m_obj_settings *af_settings;
     struct filter_opts *filter_opts;

player/audio.c

@@ -57,6 +57,12 @@ static void update_speed_filters(struct MPContext *mpctx)
     double speed = mpctx->opts->playback_speed;
     double resample = mpctx->speed_factor_a;
     double drop = 1.0;
+    char *pitch_correction_filters[] = {NULL,
+        "scaletempo2",
+        "rubberband",
+        "scaletempo",
+    };
+    char *name = pitch_correction_filters[mpctx->opts->pitch_correction];
 
     if (!mpctx->opts->pitch_correction) {
         resample *= speed;
@@ -76,7 +82,7 @@ static void update_speed_filters(struct MPContext *mpctx)
         }
     }
 
-    mp_output_chain_set_audio_speed(ao_c->filter, speed, resample, drop);
+    mp_output_chain_set_audio_speed(ao_c->filter, speed, resample, drop, name);
 }
 
 static int recreate_audio_filters(struct MPContext *mpctx)