2 * Sonitus - ResampleFilter.java - Copyright © 2013 David Roden
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 3 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 package net.pterodactylus.sonitus.data.filter;
20 import static com.google.common.base.Preconditions.*;
22 import net.pterodactylus.sonitus.data.ConnectException;
23 import net.pterodactylus.sonitus.data.Metadata;
24 import net.pterodactylus.sonitus.data.Source;
26 import com.google.common.collect.ImmutableList;
29 * {@link net.pterodactylus.sonitus.data.Filter} implementation that uses {@code
30 * sox} to resample a PCM-encoded source.
32 * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
34 public class SoxResampleFilter extends ExternalFilter {
36 /** The location of the binary. */
37 private final String binary;
39 /** The final sampling rate. */
40 private final int rate;
43 * Creates a new resample filter.
46 * The location of the binary
48 * The new sampling rate
50 public SoxResampleFilter(String binary, int rate) {
60 public Metadata metadata() {
61 return super.metadata().frequency(rate);
65 public void connect(Source source) throws ConnectException {
66 checkNotNull(source, "source must not be null");
67 checkArgument(source.metadata().encoding().equalsIgnoreCase("PCM"), "source must be PCM-encoded");
69 super.connect(source);
73 // EXTERNALFILTER METHODS
77 protected String binary(Metadata metadata) {
82 protected Iterable<String> parameters(Metadata metadata) {
83 ImmutableList.Builder<String> parameters = ImmutableList.builder();
85 parameters.add("--bits").add("16");
86 parameters.add("--channels").add(String.valueOf(metadata.channels()));
87 parameters.add("--encoding").add("signed-integer");
88 parameters.add("--rate").add(String.valueOf(metadata.frequency()));
89 parameters.add("--type").add("raw");
90 parameters.add("--endian").add("little");
92 /* the output file. */
93 parameters.add("--bits").add("16");
94 parameters.add("--channels").add(String.valueOf(metadata.channels()));
95 parameters.add("--encoding").add("signed-integer");
96 parameters.add("--type").add("raw");
97 parameters.add("--endian").add("little");
100 parameters.add("rate").add("-h").add(String.valueOf(rate));
101 return parameters.build();