aboutsummaryrefslogtreecommitdiffstats
path: root/src/pcm/SoxrResampler.cxx
blob: f335e92e68d51b49c69ea67ee556403495b8ce9c (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
/*
 * Copyright (C) 2003-2015 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 "config/Block.hxx"
#include "util/ASCII.hxx"
#include "util/Error.hxx"
#include "util/Domain.hxx"
#include "Log.hxx"

#include <soxr.h>

#include <assert.h>
#include <string.h>

static constexpr Domain soxr_domain("soxr");

static constexpr unsigned long SOXR_DEFAULT_RECIPE = SOXR_HQ;

/**
 * Special value for "invalid argument".
 */
static constexpr unsigned long SOXR_INVALID_RECIPE = -1;

static soxr_quality_spec_t soxr_quality;
static soxr_runtime_spec_t soxr_runtime;

static constexpr struct {
	unsigned long recipe;
	const char *name;
} soxr_quality_table[] = {
	{ SOXR_VHQ, "very high" },
	{ SOXR_HQ, "high" },
	{ SOXR_MQ, "medium" },
	{ SOXR_LQ, "low" },
	{ SOXR_QQ, "quick" },
	{ SOXR_INVALID_RECIPE, nullptr }
};

gcc_const
static const char *
soxr_quality_name(unsigned long recipe)
{
	for (const auto *i = soxr_quality_table;; ++i) {
		assert(i->name != nullptr);

		if (i->recipe == recipe)
			return i->name;
	}
}

gcc_pure
static unsigned long
soxr_parse_quality(const char *quality)
{
	if (quality == nullptr)
		return SOXR_DEFAULT_RECIPE;

	for (const auto *i = soxr_quality_table; i->name != nullptr; ++i)
		if (strcmp(i->name, quality) == 0)
			return i->recipe;

	return SOXR_INVALID_RECIPE;
}

bool
pcm_resample_soxr_global_init(const ConfigBlock &block, Error &error)
{
	const char *quality_string = block.GetBlockValue("quality");
	unsigned long recipe = soxr_parse_quality(quality_string);
	if (recipe == SOXR_INVALID_RECIPE) {
		assert(quality_string != nullptr);

		error.Format(soxr_domain,
			     "unknown quality setting '%s' in line %d",
			     quality_string, block.line);
		return false;
	}

	soxr_quality = soxr_quality_spec(recipe, 0);

	FormatDebug(soxr_domain,
		    "soxr converter '%s'",
		    soxr_quality_name(recipe));

	const unsigned n_threads = block.GetBlockValue("threads", 1);
	soxr_runtime = soxr_runtime_spec(n_threads);

	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 = soxr_create(af.sample_rate, new_sample_rate,
			   af.channels, &e,
			   nullptr, &soxr_quality, &soxr_runtime);
	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;

	/* always round up: worst case output buffer size */
	const size_t o_frames = size_t(n_frames * ratio) + 1;

	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 };
}