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-rw-r--r--src/pcm/SoxrResampler.cxx162
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diff --git a/src/pcm/SoxrResampler.cxx b/src/pcm/SoxrResampler.cxx
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+/*
+ * Copyright (C) 2003-2014 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "SoxrResampler.hxx"
+#include "AudioFormat.hxx"
+#include "util/ASCII.hxx"
+#include "util/Error.hxx"
+#include "util/Domain.hxx"
+#include "Log.hxx"
+
+#include <soxr.h>
+
+#include <assert.h>
+
+static constexpr Domain soxr_domain("soxr");
+
+static unsigned long soxr_quality_recipe = SOXR_HQ;
+
+static const char *
+soxr_quality_name(unsigned long recipe)
+{
+ switch (recipe) {
+ case SOXR_VHQ:
+ return "Very High Quality";
+ case SOXR_HQ:
+ return "High Quality";
+ case SOXR_MQ:
+ return "Medium Quality";
+ case SOXR_LQ:
+ return "Low Quality";
+ case SOXR_QQ:
+ return "Quick";
+ }
+
+ gcc_unreachable();
+}
+
+static bool
+soxr_parse_converter(const char *converter)
+{
+ assert(converter != nullptr);
+
+ assert(memcmp(converter, "soxr", 4) == 0);
+ if (converter[4] == '\0')
+ return true;
+ if (converter[4] != ' ')
+ return false;
+
+ // converter example is "soxr very high", we want the "very high" part
+ const char *quality = converter + 5;
+ if (strcmp(quality, "very high") == 0)
+ soxr_quality_recipe = SOXR_VHQ;
+ else if (strcmp(quality, "high") == 0)
+ soxr_quality_recipe = SOXR_HQ;
+ else if (strcmp(quality, "medium") == 0)
+ soxr_quality_recipe = SOXR_MQ;
+ else if (strcmp(quality, "low") == 0)
+ soxr_quality_recipe = SOXR_LQ;
+ else if (strcmp(quality, "quick") == 0)
+ soxr_quality_recipe = SOXR_QQ;
+ else
+ return false;
+
+ return true;
+}
+
+bool
+pcm_resample_soxr_global_init(const char *converter, Error &error)
+{
+ if (!soxr_parse_converter(converter)) {
+ error.Format(soxr_domain,
+ "unknown samplerate converter '%s'", converter);
+ return false;
+ }
+
+ FormatDebug(soxr_domain,
+ "soxr converter '%s'",
+ soxr_quality_name(soxr_quality_recipe));
+
+ return true;
+}
+
+AudioFormat
+SoxrPcmResampler::Open(AudioFormat &af, unsigned new_sample_rate,
+ Error &error)
+{
+ assert(af.IsValid());
+ assert(audio_valid_sample_rate(new_sample_rate));
+
+ soxr_error_t e;
+ soxr_quality_spec_t quality = soxr_quality_spec(soxr_quality_recipe, 0);
+ soxr = soxr_create(af.sample_rate, new_sample_rate,
+ af.channels, &e,
+ nullptr, &quality, nullptr);
+ if (soxr == nullptr) {
+ error.Format(soxr_domain,
+ "soxr initialization has failed: %s", e);
+ return AudioFormat::Undefined();
+ }
+
+ FormatDebug(soxr_domain, "soxr engine '%s'", soxr_engine(soxr));
+
+ channels = af.channels;
+
+ ratio = float(new_sample_rate) / float(af.sample_rate);
+ FormatDebug(soxr_domain,
+ "samplerate conversion ratio to %.2lf",
+ ratio);
+
+ /* libsoxr works with floating point samples */
+ af.format = SampleFormat::FLOAT;
+
+ AudioFormat result = af;
+ result.sample_rate = new_sample_rate;
+ return result;
+}
+
+void
+SoxrPcmResampler::Close()
+{
+ soxr_delete(soxr);
+}
+
+ConstBuffer<void>
+SoxrPcmResampler::Resample(ConstBuffer<void> src, Error &error)
+{
+ const size_t frame_size = channels * sizeof(float);
+ assert(src.size % frame_size == 0);
+
+ const size_t n_frames = src.size / frame_size;
+
+ const size_t o_frames = size_t(n_frames * ratio + 0.5);
+
+ float *output_buffer = (float *)buffer.Get(o_frames * frame_size);
+
+ size_t i_done, o_done;
+ soxr_error_t e = soxr_process(soxr, src.data, n_frames, &i_done,
+ output_buffer, o_frames, &o_done);
+ if (e != nullptr) {
+ error.Format(soxr_domain, "soxr error: %s", e);
+ return nullptr;
+ }
+
+ return { output_buffer, o_done * frame_size };
+}