audio: move libswresample wrapper out of audio filter code

Move it from af_lavrresample.c to a new aconverter.c file, which is
independent from the filter chain code. It also doesn't use mp_audio,
and thus has no GPL dependencies.

Preparation for later commits. Not particularly well tested, so have
fun.

1 files changed, 39 insertions, 0 deletions

diff --git a/audio/aconverter.h b/audio/aconverter.h
new file mode 100644
index 0000000000..57c5524c2f
--- /dev/null
+++ b/audio/aconverter.h
@@ -0,0 +1,39 @@
+#pragma once
+
+#include <stdbool.h>
+
+#include "chmap.h"
+
+struct mp_aconverter;
+struct mp_aframe;
+struct mpv_global;
+struct mp_log;
+
+struct mp_resample_opts {
+    int filter_size;
+    int phase_shift;
+    int linear;
+    double cutoff;
+    int normalize;
+    int allow_passthrough;
+    char **avopts;
+};
+
+#define MP_RESAMPLE_OPTS_DEF {  \
+    .filter_size = 16,          \
+    .cutoff      = 0.0,         \
+    .phase_shift = 10,          \
+    .normalize   = -1,          \
+    }
+
+struct mp_aconverter *mp_aconverter_create(struct mpv_global *global,
+                                           struct mp_log *log,
+                                           const struct mp_resample_opts *opts);
+bool mp_aconverter_reconfig(struct mp_aconverter *p,
+                    int in_rate, int in_format, struct mp_chmap in_channels,
+                    int out_rate, int out_format, struct mp_chmap out_channels);
+void mp_aconverter_flush(struct mp_aconverter *p);
+void mp_aconverter_set_speed(struct mp_aconverter *p, double speed);
+bool mp_aconverter_write_input(struct mp_aconverter *p, struct mp_aframe *in);
+struct mp_aframe *mp_aconverter_read_output(struct mp_aconverter *p, bool *eof);
+double mp_aconverter_get_latency(struct mp_aconverter *p);