pcm_resample: convert to C++

src/pcm/PcmResampleLibsamplerate.cxx

@@ -0,0 +1,295 @@
+/*
+ * Copyright (C) 2003-2013 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 "PcmResampleInternal.hxx"
+#include "conf.h"
+
+#include <glib.h>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#undef G_LOG_DOMAIN
+#define G_LOG_DOMAIN "pcm"
+
+static int lsr_converter = SRC_SINC_FASTEST;
+
+static inline GQuark
+libsamplerate_quark(void)
+{
+	return g_quark_from_static_string("libsamplerate");
+}
+
+static bool
+lsr_parse_converter(const char *s)
+{
+	assert(s != nullptr);
+
+	if (*s == 0)
+		return true;
+
+	char *endptr;
+	long l = strtol(s, &endptr, 10);
+	if (*endptr == 0 && src_get_name(l) != nullptr) {
+		lsr_converter = l;
+		return true;
+	}
+
+	size_t length = strlen(s);
+	for (int i = 0;; ++i) {
+		const char *name = src_get_name(i);
+		if (name == nullptr)
+			break;
+
+		if (g_ascii_strncasecmp(s, name, length) == 0) {
+			lsr_converter = i;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+bool
+pcm_resample_lsr_global_init(const char *converter, GError **error_r)
+{
+	if (!lsr_parse_converter(converter)) {
+		g_set_error(error_r, libsamplerate_quark(), 0,
+			    "unknown samplerate converter '%s'", converter);
+		return false;
+	}
+
+	g_debug("libsamplerate converter '%s'",
+		src_get_name(lsr_converter));
+
+	return true;
+}
+
+void
+pcm_resample_lsr_init(PcmResampler *state)
+{
+	memset(state, 0, sizeof(*state));
+
+	pcm_buffer_init(&state->in);
+	pcm_buffer_init(&state->out);
+	pcm_buffer_init(&state->buffer);
+}
+
+void
+pcm_resample_lsr_deinit(PcmResampler *state)
+{
+	if (state->state != nullptr)
+		state->state = src_delete(state->state);
+
+	pcm_buffer_deinit(&state->in);
+	pcm_buffer_deinit(&state->out);
+	pcm_buffer_deinit(&state->buffer);
+}
+
+void
+pcm_resample_lsr_reset(PcmResampler *state)
+{
+	if (state->state != nullptr)
+		src_reset(state->state);
+}
+
+static bool
+pcm_resample_set(PcmResampler *state,
+		 unsigned channels, unsigned src_rate, unsigned dest_rate,
+		 GError **error_r)
+{
+	/* (re)set the state/ratio if the in or out format changed */
+	if (channels == state->prev.channels &&
+	    src_rate == state->prev.src_rate &&
+	    dest_rate == state->prev.dest_rate)
+		return true;
+
+	state->error = 0;
+	state->prev.channels = channels;
+	state->prev.src_rate = src_rate;
+	state->prev.dest_rate = dest_rate;
+
+	if (state->state)
+		state->state = src_delete(state->state);
+
+	int error;
+	state->state = src_new(lsr_converter, channels, &error);
+	if (!state->state) {
+		g_set_error(error_r, libsamplerate_quark(), state->error,
+			    "libsamplerate initialization has failed: %s",
+			    src_strerror(error));
+		return false;
+	}
+
+	SRC_DATA *data = &state->data;
+	data->src_ratio = (double)dest_rate / (double)src_rate;
+	g_debug("setting samplerate conversion ratio to %.2lf",
+		data->src_ratio);
+	src_set_ratio(state->state, data->src_ratio);
+
+	return true;
+}
+
+static bool
+lsr_process(PcmResampler *state, GError **error_r)
+{
+	if (state->error == 0)
+		state->error = src_process(state->state, &state->data);
+	if (state->error) {
+		g_set_error(error_r, libsamplerate_quark(), state->error,
+			    "libsamplerate has failed: %s",
+			    src_strerror(state->error));
+		return false;
+	}
+
+	return true;
+}
+
+const float *
+pcm_resample_lsr_float(PcmResampler *state,
+		       unsigned channels,
+		       unsigned src_rate,
+		       const float *src_buffer, size_t src_size,
+		       unsigned dest_rate, size_t *dest_size_r,
+		       GError **error_r)
+{
+	SRC_DATA *data = &state->data;
+
+	assert((src_size % (sizeof(*src_buffer) * channels)) == 0);
+
+	if (!pcm_resample_set(state, channels, src_rate, dest_rate, error_r))
+		return nullptr;
+
+
+	data->input_frames = src_size / sizeof(*src_buffer) / channels;
+	data->data_in = const_cast<float *>(src_buffer);
+
+	data->output_frames = (src_size * dest_rate + src_rate - 1) / src_rate;
+	size_t data_out_size = data->output_frames * sizeof(float) * channels;
+	data->data_out = (float *)pcm_buffer_get(&state->out, data_out_size);
+
+	if (!lsr_process(state, error_r))
+		return nullptr;
+
+	*dest_size_r = data->output_frames_gen *
+		sizeof(*data->data_out) * channels;
+	return data->data_out;
+}
+
+const int16_t *
+pcm_resample_lsr_16(PcmResampler *state,
+		    unsigned channels,
+		    unsigned src_rate,
+		    const int16_t *src_buffer, size_t src_size,
+		    unsigned dest_rate, size_t *dest_size_r,
+		    GError **error_r)
+{
+	SRC_DATA *data = &state->data;
+
+	assert((src_size % (sizeof(*src_buffer) * channels)) == 0);
+
+	if (!pcm_resample_set(state, channels, src_rate, dest_rate,
+			      error_r))
+		return nullptr;
+
+	data->input_frames = src_size / sizeof(*src_buffer) / channels;
+	size_t data_in_size = data->input_frames * sizeof(float) * channels;
+	data->data_in = (float *)pcm_buffer_get(&state->in, data_in_size);
+
+	data->output_frames = (src_size * dest_rate + src_rate - 1) / src_rate;
+	size_t data_out_size = data->output_frames * sizeof(float) * channels;
+	data->data_out = (float *)pcm_buffer_get(&state->out, data_out_size);
+
+	src_short_to_float_array(src_buffer, data->data_in,
+				 data->input_frames * channels);
+
+	if (!lsr_process(state, error_r))
+		return nullptr;
+
+	int16_t *dest_buffer;
+	*dest_size_r = data->output_frames_gen *
+		sizeof(*dest_buffer) * channels;
+	dest_buffer = (int16_t *)pcm_buffer_get(&state->buffer, *dest_size_r);
+	src_float_to_short_array(data->data_out, dest_buffer,
+				 data->output_frames_gen * channels);
+
+	return dest_buffer;
+}
+
+#ifdef HAVE_LIBSAMPLERATE_NOINT
+
+/* libsamplerate introduced these functions in v0.1.3 */
+
+static void
+src_int_to_float_array(const int *in, float *out, int len)
+{
+	while (len-- > 0)
+		*out++ = *in++ / (float)(1 << (24 - 1));
+}
+
+static void
+src_float_to_int_array (const float *in, int *out, int len)
+{
+	while (len-- > 0)
+		*out++ = *in++ * (float)(1 << (24 - 1));
+}
+
+#endif
+
+const int32_t *
+pcm_resample_lsr_32(PcmResampler *state,
+		    unsigned channels,
+		    unsigned src_rate,
+		    const int32_t *src_buffer, size_t src_size,
+		    unsigned dest_rate, size_t *dest_size_r,
+		    GError **error_r)
+{
+	SRC_DATA *data = &state->data;
+
+	assert((src_size % (sizeof(*src_buffer) * channels)) == 0);
+
+	if (!pcm_resample_set(state, channels, src_rate, dest_rate,
+			      error_r))
+		return nullptr;
+
+	data->input_frames = src_size / sizeof(*src_buffer) / channels;
+	size_t data_in_size = data->input_frames * sizeof(float) * channels;
+	data->data_in = (float *)pcm_buffer_get(&state->in, data_in_size);
+
+	data->output_frames = (src_size * dest_rate + src_rate - 1) / src_rate;
+	size_t data_out_size = data->output_frames * sizeof(float) * channels;
+	data->data_out = (float *)pcm_buffer_get(&state->out, data_out_size);
+
+	src_int_to_float_array(src_buffer, data->data_in,
+			       data->input_frames * channels);
+
+	if (!lsr_process(state, error_r))
+		return nullptr;
+
+	int32_t *dest_buffer;
+	*dest_size_r = data->output_frames_gen *
+		sizeof(*dest_buffer) * channels;
+	dest_buffer = (int32_t *)pcm_buffer_get(&state->buffer, *dest_size_r);
+	src_float_to_int_array(data->data_out, dest_buffer,
+			       data->output_frames_gen * channels);
+
+	return dest_buffer;
+}