1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.media;
18
19import android.annotation.IntDef;
20import android.annotation.NonNull;
21import android.annotation.TestApi;
22import android.os.Parcel;
23import android.os.Parcelable;
24
25import java.lang.annotation.Retention;
26import java.lang.annotation.RetentionPolicy;
27import java.util.Arrays;
28import java.util.Objects;
29
30/**
31 * The {@link AudioFormat} class is used to access a number of audio format and
32 * channel configuration constants. They are for instance used
33 * in {@link AudioTrack} and {@link AudioRecord}, as valid values in individual parameters of
34 * constructors like {@link AudioTrack#AudioTrack(int, int, int, int, int, int)}, where the fourth
35 * parameter is one of the <code>AudioFormat.ENCODING_*</code> constants.
36 * The <code>AudioFormat</code> constants are also used in {@link MediaFormat} to specify
37 * audio related values commonly used in media, such as for {@link MediaFormat#KEY_CHANNEL_MASK}.
38 * <p>The {@link AudioFormat.Builder} class can be used to create instances of
39 * the <code>AudioFormat</code> format class.
40 * Refer to
41 * {@link AudioFormat.Builder} for documentation on the mechanics of the configuration and building
42 * of such instances. Here we describe the main concepts that the <code>AudioFormat</code> class
43 * allow you to convey in each instance, they are:
44 * <ol>
45 * <li><a href="#sampleRate">sample rate</a>
46 * <li><a href="#encoding">encoding</a>
47 * <li><a href="#channelMask">channel masks</a>
48 * </ol>
49 * <p>Closely associated with the <code>AudioFormat</code> is the notion of an
50 * <a href="#audioFrame">audio frame</a>, which is used throughout the documentation
51 * to represent the minimum size complete unit of audio data.
52 *
53 * <h4 id="sampleRate">Sample rate</h4>
54 * <p>Expressed in Hz, the sample rate in an <code>AudioFormat</code> instance expresses the number
55 * of audio samples for each channel per second in the content you are playing or recording. It is
56 * not the sample rate
57 * at which content is rendered or produced. For instance a sound at a media sample rate of 8000Hz
58 * can be played on a device operating at a sample rate of 48000Hz; the sample rate conversion is
59 * automatically handled by the platform, it will not play at 6x speed.
60 *
61 * <p>As of API {@link android.os.Build.VERSION_CODES#M},
62 * sample rates up to 192kHz are supported
63 * for <code>AudioRecord</code> and <code>AudioTrack</code>, with sample rate conversion
64 * performed as needed.
65 * To improve efficiency and avoid lossy conversions, it is recommended to match the sample rate
66 * for <code>AudioRecord</code> and <code>AudioTrack</code> to the endpoint device
67 * sample rate, and limit the sample rate to no more than 48kHz unless there are special
68 * device capabilities that warrant a higher rate.
69 *
70 * <h4 id="encoding">Encoding</h4>
71 * <p>Audio encoding is used to describe the bit representation of audio data, which can be
72 * either linear PCM or compressed audio, such as AC3 or DTS.
73 * <p>For linear PCM, the audio encoding describes the sample size, 8 bits, 16 bits, or 32 bits,
74 * and the sample representation, integer or float.
75 * <ul>
76 * <li> {@link #ENCODING_PCM_8BIT}: The audio sample is a 8 bit unsigned integer in the
77 * range [0, 255], with a 128 offset for zero. This is typically stored as a Java byte in a
78 * byte array or ByteBuffer. Since the Java byte is <em>signed</em>,
79 * be careful with math operations and conversions as the most significant bit is inverted.
80 * </li>
81 * <li> {@link #ENCODING_PCM_16BIT}: The audio sample is a 16 bit signed integer
82 * typically stored as a Java short in a short array, but when the short
83 * is stored in a ByteBuffer, it is native endian (as compared to the default Java big endian).
84 * The short has full range from [-32768, 32767],
85 * and is sometimes interpreted as fixed point Q.15 data.
86 * </li>
87 * <li> {@link #ENCODING_PCM_FLOAT}: Introduced in
88 * API {@link android.os.Build.VERSION_CODES#LOLLIPOP}, this encoding specifies that
89 * the audio sample is a 32 bit IEEE single precision float. The sample can be
90 * manipulated as a Java float in a float array, though within a ByteBuffer
91 * it is stored in native endian byte order.
92 * The nominal range of <code>ENCODING_PCM_FLOAT</code> audio data is [-1.0, 1.0].
93 * It is implementation dependent whether the positive maximum of 1.0 is included
94 * in the interval. Values outside of the nominal range are clamped before
95 * sending to the endpoint device. Beware that
96 * the handling of NaN is undefined; subnormals may be treated as zero; and
97 * infinities are generally clamped just like other values for <code>AudioTrack</code>
98 * &ndash; try to avoid infinities because they can easily generate a NaN.
99 * <br>
100 * To achieve higher audio bit depth than a signed 16 bit integer short,
101 * it is recommended to use <code>ENCODING_PCM_FLOAT</code> for audio capture, processing,
102 * and playback.
103 * Floats are efficiently manipulated by modern CPUs,
104 * have greater precision than 24 bit signed integers,
105 * and have greater dynamic range than 32 bit signed integers.
106 * <code>AudioRecord</code> as of API {@link android.os.Build.VERSION_CODES#M} and
107 * <code>AudioTrack</code> as of API {@link android.os.Build.VERSION_CODES#LOLLIPOP}
108 * support <code>ENCODING_PCM_FLOAT</code>.
109 * </li>
110 * </ul>
111 * <p>For compressed audio, the encoding specifies the method of compression,
112 * for example {@link #ENCODING_AC3} and {@link #ENCODING_DTS}. The compressed
113 * audio data is typically stored as bytes in
114 * a byte array or ByteBuffer. When a compressed audio encoding is specified
115 * for an <code>AudioTrack</code>, it creates a direct (non-mixed) track
116 * for output to an endpoint (such as HDMI) capable of decoding the compressed audio.
117 * For (most) other endpoints, which are not capable of decoding such compressed audio,
118 * you will need to decode the data first, typically by creating a {@link MediaCodec}.
119 * Alternatively, one may use {@link MediaPlayer} for playback of compressed
120 * audio files or streams.
121 * <p>When compressed audio is sent out through a direct <code>AudioTrack</code>,
122 * it need not be written in exact multiples of the audio access unit;
123 * this differs from <code>MediaCodec</code> input buffers.
124 *
125 * <h4 id="channelMask">Channel mask</h4>
126 * <p>Channel masks are used in <code>AudioTrack</code> and <code>AudioRecord</code> to describe
127 * the samples and their arrangement in the audio frame. They are also used in the endpoint (e.g.
128 * a USB audio interface, a DAC connected to headphones) to specify allowable configurations of a
129 * particular device.
130 * <br>As of API {@link android.os.Build.VERSION_CODES#M}, there are two types of channel masks:
131 * channel position masks and channel index masks.
132 *
133 * <h5 id="channelPositionMask">Channel position masks</h5>
134 * Channel position masks are the original Android channel masks, and are used since API
135 * {@link android.os.Build.VERSION_CODES#BASE}.
136 * For input and output, they imply a positional nature - the location of a speaker or a microphone
137 * for recording or playback.
138 * <br>For a channel position mask, each allowed channel position corresponds to a bit in the
139 * channel mask. If that channel position is present in the audio frame, that bit is set,
140 * otherwise it is zero. The order of the bits (from lsb to msb) corresponds to the order of that
141 * position's sample in the audio frame.
142 * <br>The canonical channel position masks by channel count are as follows:
143 * <br><table>
144 * <tr><td>channel count</td><td>channel position mask</td></tr>
145 * <tr><td>1</td><td>{@link #CHANNEL_OUT_MONO}</td></tr>
146 * <tr><td>2</td><td>{@link #CHANNEL_OUT_STEREO}</td></tr>
147 * <tr><td>3</td><td>{@link #CHANNEL_OUT_STEREO} | {@link #CHANNEL_OUT_FRONT_CENTER}</td></tr>
148 * <tr><td>4</td><td>{@link #CHANNEL_OUT_QUAD}</td></tr>
149 * <tr><td>5</td><td>{@link #CHANNEL_OUT_QUAD} | {@link #CHANNEL_OUT_FRONT_CENTER}</td></tr>
150 * <tr><td>6</td><td>{@link #CHANNEL_OUT_5POINT1}</td></tr>
151 * <tr><td>7</td><td>{@link #CHANNEL_OUT_5POINT1} | {@link #CHANNEL_OUT_BACK_CENTER}</td></tr>
152 * <tr><td>8</td><td>{@link #CHANNEL_OUT_7POINT1_SURROUND}</td></tr>
153 * </table>
154 * <br>These masks are an ORed composite of individual channel masks. For example
155 * {@link #CHANNEL_OUT_STEREO} is composed of {@link #CHANNEL_OUT_FRONT_LEFT} and
156 * {@link #CHANNEL_OUT_FRONT_RIGHT}.
157 *
158 * <h5 id="channelIndexMask">Channel index masks</h5>
159 * Channel index masks are introduced in API {@link android.os.Build.VERSION_CODES#M}. They allow
160 * the selection of a particular channel from the source or sink endpoint by number, i.e. the first
161 * channel, the second channel, and so forth. This avoids problems with artificially assigning
162 * positions to channels of an endpoint, or figuring what the i<sup>th</sup> position bit is within
163 * an endpoint's channel position mask etc.
164 * <br>Here's an example where channel index masks address this confusion: dealing with a 4 channel
165 * USB device. Using a position mask, and based on the channel count, this would be a
166 * {@link #CHANNEL_OUT_QUAD} device, but really one is only interested in channel 0
167 * through channel 3. The USB device would then have the following individual bit channel masks:
168 * {@link #CHANNEL_OUT_FRONT_LEFT},
169 * {@link #CHANNEL_OUT_FRONT_RIGHT}, {@link #CHANNEL_OUT_BACK_LEFT}
170 * and {@link #CHANNEL_OUT_BACK_RIGHT}. But which is channel 0 and which is
171 * channel 3?
172 * <br>For a channel index mask, each channel number is represented as a bit in the mask, from the
173 * lsb (channel 0) upwards to the msb, numerically this bit value is
174 * <code>1 << channelNumber</code>.
175 * A set bit indicates that channel is present in the audio frame, otherwise it is cleared.
176 * The order of the bits also correspond to that channel number's sample order in the audio frame.
177 * <br>For the previous 4 channel USB device example, the device would have a channel index mask
178 * <code>0xF</code>. Suppose we wanted to select only the first and the third channels; this would
179 * correspond to a channel index mask <code>0x5</code> (the first and third bits set). If an
180 * <code>AudioTrack</code> uses this channel index mask, the audio frame would consist of two
181 * samples, the first sample of each frame routed to channel 0, and the second sample of each frame
182 * routed to channel 2.
183 * The canonical channel index masks by channel count are given by the formula
184 * <code>(1 << channelCount) - 1</code>.
185 *
186 * <h5>Use cases</h5>
187 * <ul>
188 * <li><i>Channel position mask for an endpoint:</i> <code>CHANNEL_OUT_FRONT_LEFT</code>,
189 *  <code>CHANNEL_OUT_FRONT_CENTER</code>, etc. for HDMI home theater purposes.
190 * <li><i>Channel position mask for an audio stream:</i> Creating an <code>AudioTrack</code>
191 *  to output movie content, where 5.1 multichannel output is to be written.
192 * <li><i>Channel index mask for an endpoint:</i> USB devices for which input and output do not
193 *  correspond to left or right speaker or microphone.
194 * <li><i>Channel index mask for an audio stream:</i> An <code>AudioRecord</code> may only want the
195 *  third and fourth audio channels of the endpoint (i.e. the second channel pair), and not care the
196 *  about position it corresponds to, in which case the channel index mask is <code>0xC</code>.
197 *  Multichannel <code>AudioRecord</code> sessions should use channel index masks.
198 * </ul>
199 * <h4 id="audioFrame">Audio Frame</h4>
200 * <p>For linear PCM, an audio frame consists of a set of samples captured at the same time,
201 * whose count and
202 * channel association are given by the <a href="#channelMask">channel mask</a>,
203 * and whose sample contents are specified by the <a href="#encoding">encoding</a>.
204 * For example, a stereo 16 bit PCM frame consists of
205 * two 16 bit linear PCM samples, with a frame size of 4 bytes.
206 * For compressed audio, an audio frame may alternately
207 * refer to an access unit of compressed data bytes that is logically grouped together for
208 * decoding and bitstream access (e.g. {@link MediaCodec}),
209 * or a single byte of compressed data (e.g. {@link AudioTrack#getBufferSizeInFrames()
210 * AudioTrack.getBufferSizeInFrames()}),
211 * or the linear PCM frame result from decoding the compressed data
212 * (e.g.{@link AudioTrack#getPlaybackHeadPosition()
213 * AudioTrack.getPlaybackHeadPosition()}),
214 * depending on the context where audio frame is used.
215 */
216public final class AudioFormat implements Parcelable {
217
218    //---------------------------------------------------------
219    // Constants
220    //--------------------
221    /** Invalid audio data format */
222    public static final int ENCODING_INVALID = 0;
223    /** Default audio data format */
224    public static final int ENCODING_DEFAULT = 1;
225
226    // These values must be kept in sync with core/jni/android_media_AudioFormat.h
227    // Also sync av/services/audiopolicy/managerdefault/ConfigParsingUtils.h
228    /** Audio data format: PCM 16 bit per sample. Guaranteed to be supported by devices. */
229    public static final int ENCODING_PCM_16BIT = 2;
230    /** Audio data format: PCM 8 bit per sample. Not guaranteed to be supported by devices. */
231    public static final int ENCODING_PCM_8BIT = 3;
232    /** Audio data format: single-precision floating-point per sample */
233    public static final int ENCODING_PCM_FLOAT = 4;
234    /** Audio data format: AC-3 compressed */
235    public static final int ENCODING_AC3 = 5;
236    /** Audio data format: E-AC-3 compressed */
237    public static final int ENCODING_E_AC3 = 6;
238    /** Audio data format: DTS compressed */
239    public static final int ENCODING_DTS = 7;
240    /** Audio data format: DTS HD compressed */
241    public static final int ENCODING_DTS_HD = 8;
242    /** Audio data format: MP3 compressed */
243    public static final int ENCODING_MP3 = 9;
244    /** Audio data format: AAC LC compressed */
245    public static final int ENCODING_AAC_LC = 10;
246    /** Audio data format: AAC HE V1 compressed */
247    public static final int ENCODING_AAC_HE_V1 = 11;
248    /** Audio data format: AAC HE V2 compressed */
249    public static final int ENCODING_AAC_HE_V2 = 12;
250
251    /** Audio data format: compressed audio wrapped in PCM for HDMI
252     * or S/PDIF passthrough.
253     * IEC61937 uses a stereo stream of 16-bit samples as the wrapper.
254     * So the channel mask for the track must be {@link #CHANNEL_OUT_STEREO}.
255     * Data should be written to the stream in a short[] array.
256     * If the data is written in a byte[] array then there may be endian problems
257     * on some platforms when converting to short internally.
258     */
259    public static final int ENCODING_IEC61937 = 13;
260    /** Audio data format: DOLBY TRUEHD compressed
261     **/
262    public static final int ENCODING_DOLBY_TRUEHD = 14;
263    /** Audio data format: AAC ELD compressed */
264    public static final int ENCODING_AAC_ELD = 15;
265    /** Audio data format: AAC xHE compressed */
266    public static final int ENCODING_AAC_XHE = 16;
267    /** Audio data format: AC-4 sync frame transport format */
268    public static final int ENCODING_AC4 = 17;
269    /** Audio data format: E-AC-3-JOC compressed
270     * E-AC-3-JOC streams can be decoded by downstream devices supporting {@link #ENCODING_E_AC3}.
271     * Use {@link #ENCODING_E_AC3} as the AudioTrack encoding when the downstream device
272     * supports {@link #ENCODING_E_AC3} but not {@link #ENCODING_E_AC3_JOC}.
273     **/
274    public static final int ENCODING_E_AC3_JOC = 18;
275
276    /** @hide */
277    public static String toLogFriendlyEncoding(int enc) {
278        switch(enc) {
279            case ENCODING_INVALID:
280                return "ENCODING_INVALID";
281            case ENCODING_PCM_16BIT:
282                return "ENCODING_PCM_16BIT";
283            case ENCODING_PCM_8BIT:
284                return "ENCODING_PCM_8BIT";
285            case ENCODING_PCM_FLOAT:
286                return "ENCODING_PCM_FLOAT";
287            case ENCODING_AC3:
288                return "ENCODING_AC3";
289            case ENCODING_E_AC3:
290                return "ENCODING_E_AC3";
291            case ENCODING_DTS:
292                return "ENCODING_DTS";
293            case ENCODING_DTS_HD:
294                return "ENCODING_DTS_HD";
295            case ENCODING_MP3:
296                return "ENCODING_MP3";
297            case ENCODING_AAC_LC:
298                return "ENCODING_AAC_LC";
299            case ENCODING_AAC_HE_V1:
300                return "ENCODING_AAC_HE_V1";
301            case ENCODING_AAC_HE_V2:
302                return "ENCODING_AAC_HE_V2";
303            case ENCODING_IEC61937:
304                return "ENCODING_IEC61937";
305            case ENCODING_DOLBY_TRUEHD:
306                return "ENCODING_DOLBY_TRUEHD";
307            case ENCODING_AAC_ELD:
308                return "ENCODING_AAC_ELD";
309            case ENCODING_AAC_XHE:
310                return "ENCODING_AAC_XHE";
311            case ENCODING_AC4:
312                return "ENCODING_AC4";
313            default :
314                return "invalid encoding " + enc;
315        }
316    }
317
318    /** Invalid audio channel configuration */
319    /** @deprecated Use {@link #CHANNEL_INVALID} instead.  */
320    @Deprecated    public static final int CHANNEL_CONFIGURATION_INVALID   = 0;
321    /** Default audio channel configuration */
322    /** @deprecated Use {@link #CHANNEL_OUT_DEFAULT} or {@link #CHANNEL_IN_DEFAULT} instead.  */
323    @Deprecated    public static final int CHANNEL_CONFIGURATION_DEFAULT   = 1;
324    /** Mono audio configuration */
325    /** @deprecated Use {@link #CHANNEL_OUT_MONO} or {@link #CHANNEL_IN_MONO} instead.  */
326    @Deprecated    public static final int CHANNEL_CONFIGURATION_MONO      = 2;
327    /** Stereo (2 channel) audio configuration */
328    /** @deprecated Use {@link #CHANNEL_OUT_STEREO} or {@link #CHANNEL_IN_STEREO} instead.  */
329    @Deprecated    public static final int CHANNEL_CONFIGURATION_STEREO    = 3;
330
331    /** Invalid audio channel mask */
332    public static final int CHANNEL_INVALID = 0;
333    /** Default audio channel mask */
334    public static final int CHANNEL_OUT_DEFAULT = 1;
335
336    // Output channel mask definitions below are translated to the native values defined in
337    //  in /system/media/audio/include/system/audio.h in the JNI code of AudioTrack
338    public static final int CHANNEL_OUT_FRONT_LEFT = 0x4;
339    public static final int CHANNEL_OUT_FRONT_RIGHT = 0x8;
340    public static final int CHANNEL_OUT_FRONT_CENTER = 0x10;
341    public static final int CHANNEL_OUT_LOW_FREQUENCY = 0x20;
342    public static final int CHANNEL_OUT_BACK_LEFT = 0x40;
343    public static final int CHANNEL_OUT_BACK_RIGHT = 0x80;
344    public static final int CHANNEL_OUT_FRONT_LEFT_OF_CENTER = 0x100;
345    public static final int CHANNEL_OUT_FRONT_RIGHT_OF_CENTER = 0x200;
346    public static final int CHANNEL_OUT_BACK_CENTER = 0x400;
347    public static final int CHANNEL_OUT_SIDE_LEFT =         0x800;
348    public static final int CHANNEL_OUT_SIDE_RIGHT =       0x1000;
349    /** @hide */
350    public static final int CHANNEL_OUT_TOP_CENTER =       0x2000;
351    /** @hide */
352    public static final int CHANNEL_OUT_TOP_FRONT_LEFT =   0x4000;
353    /** @hide */
354    public static final int CHANNEL_OUT_TOP_FRONT_CENTER = 0x8000;
355    /** @hide */
356    public static final int CHANNEL_OUT_TOP_FRONT_RIGHT = 0x10000;
357    /** @hide */
358    public static final int CHANNEL_OUT_TOP_BACK_LEFT =   0x20000;
359    /** @hide */
360    public static final int CHANNEL_OUT_TOP_BACK_CENTER = 0x40000;
361    /** @hide */
362    public static final int CHANNEL_OUT_TOP_BACK_RIGHT =  0x80000;
363
364    public static final int CHANNEL_OUT_MONO = CHANNEL_OUT_FRONT_LEFT;
365    public static final int CHANNEL_OUT_STEREO = (CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_RIGHT);
366    // aka QUAD_BACK
367    public static final int CHANNEL_OUT_QUAD = (CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_RIGHT |
368            CHANNEL_OUT_BACK_LEFT | CHANNEL_OUT_BACK_RIGHT);
369    /** @hide */
370    public static final int CHANNEL_OUT_QUAD_SIDE = (CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_RIGHT |
371            CHANNEL_OUT_SIDE_LEFT | CHANNEL_OUT_SIDE_RIGHT);
372    public static final int CHANNEL_OUT_SURROUND = (CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_RIGHT |
373            CHANNEL_OUT_FRONT_CENTER | CHANNEL_OUT_BACK_CENTER);
374    // aka 5POINT1_BACK
375    public static final int CHANNEL_OUT_5POINT1 = (CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_RIGHT |
376            CHANNEL_OUT_FRONT_CENTER | CHANNEL_OUT_LOW_FREQUENCY | CHANNEL_OUT_BACK_LEFT | CHANNEL_OUT_BACK_RIGHT);
377    /** @hide */
378    public static final int CHANNEL_OUT_5POINT1_SIDE = (CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_RIGHT |
379            CHANNEL_OUT_FRONT_CENTER | CHANNEL_OUT_LOW_FREQUENCY |
380            CHANNEL_OUT_SIDE_LEFT | CHANNEL_OUT_SIDE_RIGHT);
381    // different from AUDIO_CHANNEL_OUT_7POINT1 used internally, and not accepted by AudioRecord.
382    /** @deprecated Not the typical 7.1 surround configuration. Use {@link #CHANNEL_OUT_7POINT1_SURROUND} instead. */
383    @Deprecated    public static final int CHANNEL_OUT_7POINT1 = (CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_RIGHT |
384            CHANNEL_OUT_FRONT_CENTER | CHANNEL_OUT_LOW_FREQUENCY | CHANNEL_OUT_BACK_LEFT | CHANNEL_OUT_BACK_RIGHT |
385            CHANNEL_OUT_FRONT_LEFT_OF_CENTER | CHANNEL_OUT_FRONT_RIGHT_OF_CENTER);
386    // matches AUDIO_CHANNEL_OUT_7POINT1
387    public static final int CHANNEL_OUT_7POINT1_SURROUND = (
388            CHANNEL_OUT_FRONT_LEFT | CHANNEL_OUT_FRONT_CENTER | CHANNEL_OUT_FRONT_RIGHT |
389            CHANNEL_OUT_SIDE_LEFT | CHANNEL_OUT_SIDE_RIGHT |
390            CHANNEL_OUT_BACK_LEFT | CHANNEL_OUT_BACK_RIGHT |
391            CHANNEL_OUT_LOW_FREQUENCY);
392    // CHANNEL_OUT_ALL is not yet defined; if added then it should match AUDIO_CHANNEL_OUT_ALL
393
394    /** Minimum value for sample rate,
395     *  assuming AudioTrack and AudioRecord share the same limitations.
396     * @hide
397     */
398    // never unhide
399    public static final int SAMPLE_RATE_HZ_MIN = 4000;
400    /** Maximum value for sample rate,
401     *  assuming AudioTrack and AudioRecord share the same limitations.
402     * @hide
403     */
404    // never unhide
405    public static final int SAMPLE_RATE_HZ_MAX = 192000;
406    /** Sample rate will be a route-dependent value.
407     * For AudioTrack, it is usually the sink sample rate,
408     * and for AudioRecord it is usually the source sample rate.
409     */
410    public static final int SAMPLE_RATE_UNSPECIFIED = 0;
411
412    /**
413     * @hide
414     * Return the input channel mask corresponding to an output channel mask.
415     * This can be used for submix rerouting for the mask of the recorder to map to that of the mix.
416     * @param outMask a combination of the CHANNEL_OUT_* definitions, but not CHANNEL_OUT_DEFAULT
417     * @return a combination of CHANNEL_IN_* definitions matching an output channel mask
418     * @throws IllegalArgumentException
419     */
420    public static int inChannelMaskFromOutChannelMask(int outMask) throws IllegalArgumentException {
421        if (outMask == CHANNEL_OUT_DEFAULT) {
422            throw new IllegalArgumentException(
423                    "Illegal CHANNEL_OUT_DEFAULT channel mask for input.");
424        }
425        switch (channelCountFromOutChannelMask(outMask)) {
426            case 1:
427                return CHANNEL_IN_MONO;
428            case 2:
429                return CHANNEL_IN_STEREO;
430            default:
431                throw new IllegalArgumentException("Unsupported channel configuration for input.");
432        }
433    }
434
435    /**
436     * @hide
437     * Return the number of channels from an input channel mask
438     * @param mask a combination of the CHANNEL_IN_* definitions, even CHANNEL_IN_DEFAULT
439     * @return number of channels for the mask
440     */
441    @TestApi
442    public static int channelCountFromInChannelMask(int mask) {
443        return Integer.bitCount(mask);
444    }
445    /**
446     * @hide
447     * Return the number of channels from an output channel mask
448     * @param mask a combination of the CHANNEL_OUT_* definitions, but not CHANNEL_OUT_DEFAULT
449     * @return number of channels for the mask
450     */
451    @TestApi
452    public static int channelCountFromOutChannelMask(int mask) {
453        return Integer.bitCount(mask);
454    }
455    /**
456     * @hide
457     * Return a channel mask ready to be used by native code
458     * @param mask a combination of the CHANNEL_OUT_* definitions, but not CHANNEL_OUT_DEFAULT
459     * @return a native channel mask
460     */
461    public static int convertChannelOutMaskToNativeMask(int javaMask) {
462        return (javaMask >> 2);
463    }
464
465    /**
466     * @hide
467     * Return a java output channel mask
468     * @param mask a native channel mask
469     * @return a combination of the CHANNEL_OUT_* definitions
470     */
471    public static int convertNativeChannelMaskToOutMask(int nativeMask) {
472        return (nativeMask << 2);
473    }
474
475    public static final int CHANNEL_IN_DEFAULT = 1;
476    // These directly match native
477    public static final int CHANNEL_IN_LEFT = 0x4;
478    public static final int CHANNEL_IN_RIGHT = 0x8;
479    public static final int CHANNEL_IN_FRONT = 0x10;
480    public static final int CHANNEL_IN_BACK = 0x20;
481    public static final int CHANNEL_IN_LEFT_PROCESSED = 0x40;
482    public static final int CHANNEL_IN_RIGHT_PROCESSED = 0x80;
483    public static final int CHANNEL_IN_FRONT_PROCESSED = 0x100;
484    public static final int CHANNEL_IN_BACK_PROCESSED = 0x200;
485    public static final int CHANNEL_IN_PRESSURE = 0x400;
486    public static final int CHANNEL_IN_X_AXIS = 0x800;
487    public static final int CHANNEL_IN_Y_AXIS = 0x1000;
488    public static final int CHANNEL_IN_Z_AXIS = 0x2000;
489    public static final int CHANNEL_IN_VOICE_UPLINK = 0x4000;
490    public static final int CHANNEL_IN_VOICE_DNLINK = 0x8000;
491    public static final int CHANNEL_IN_MONO = CHANNEL_IN_FRONT;
492    public static final int CHANNEL_IN_STEREO = (CHANNEL_IN_LEFT | CHANNEL_IN_RIGHT);
493    /** @hide */
494    public static final int CHANNEL_IN_FRONT_BACK = CHANNEL_IN_FRONT | CHANNEL_IN_BACK;
495    // CHANNEL_IN_ALL is not yet defined; if added then it should match AUDIO_CHANNEL_IN_ALL
496
497    /** @hide */
498    @TestApi
499    public static int getBytesPerSample(int audioFormat)
500    {
501        switch (audioFormat) {
502        case ENCODING_PCM_8BIT:
503            return 1;
504        case ENCODING_PCM_16BIT:
505        case ENCODING_IEC61937:
506        case ENCODING_DEFAULT:
507            return 2;
508        case ENCODING_PCM_FLOAT:
509            return 4;
510        case ENCODING_INVALID:
511        default:
512            throw new IllegalArgumentException("Bad audio format " + audioFormat);
513        }
514    }
515
516    /** @hide */
517    public static boolean isValidEncoding(int audioFormat)
518    {
519        switch (audioFormat) {
520        case ENCODING_PCM_8BIT:
521        case ENCODING_PCM_16BIT:
522        case ENCODING_PCM_FLOAT:
523        case ENCODING_AC3:
524        case ENCODING_E_AC3:
525        case ENCODING_E_AC3_JOC:
526        case ENCODING_DTS:
527        case ENCODING_DTS_HD:
528        case ENCODING_MP3:
529        case ENCODING_AAC_LC:
530        case ENCODING_AAC_HE_V1:
531        case ENCODING_AAC_HE_V2:
532        case ENCODING_IEC61937:
533        case ENCODING_AAC_ELD:
534        case ENCODING_AAC_XHE:
535        case ENCODING_AC4:
536            return true;
537        default:
538            return false;
539        }
540    }
541
542    /** @hide */
543    public static boolean isPublicEncoding(int audioFormat)
544    {
545        switch (audioFormat) {
546        case ENCODING_PCM_8BIT:
547        case ENCODING_PCM_16BIT:
548        case ENCODING_PCM_FLOAT:
549        case ENCODING_AC3:
550        case ENCODING_E_AC3:
551        case ENCODING_E_AC3_JOC:
552        case ENCODING_DTS:
553        case ENCODING_DTS_HD:
554        case ENCODING_IEC61937:
555        case ENCODING_MP3:
556        case ENCODING_AAC_LC:
557        case ENCODING_AAC_HE_V1:
558        case ENCODING_AAC_HE_V2:
559        case ENCODING_AAC_ELD:
560        case ENCODING_AAC_XHE:
561        case ENCODING_AC4:
562            return true;
563        default:
564            return false;
565        }
566    }
567
568    /** @hide */
569    @TestApi
570    public static boolean isEncodingLinearPcm(int audioFormat)
571    {
572        switch (audioFormat) {
573        case ENCODING_PCM_8BIT:
574        case ENCODING_PCM_16BIT:
575        case ENCODING_PCM_FLOAT:
576        case ENCODING_DEFAULT:
577            return true;
578        case ENCODING_AC3:
579        case ENCODING_E_AC3:
580        case ENCODING_E_AC3_JOC:
581        case ENCODING_DTS:
582        case ENCODING_DTS_HD:
583        case ENCODING_MP3:
584        case ENCODING_AAC_LC:
585        case ENCODING_AAC_HE_V1:
586        case ENCODING_AAC_HE_V2:
587        case ENCODING_IEC61937: // wrapped in PCM but compressed
588        case ENCODING_AAC_ELD:
589        case ENCODING_AAC_XHE:
590        case ENCODING_AC4:
591            return false;
592        case ENCODING_INVALID:
593        default:
594            throw new IllegalArgumentException("Bad audio format " + audioFormat);
595        }
596    }
597
598    /** @hide */
599    public static boolean isEncodingLinearFrames(int audioFormat)
600    {
601        switch (audioFormat) {
602        case ENCODING_PCM_8BIT:
603        case ENCODING_PCM_16BIT:
604        case ENCODING_PCM_FLOAT:
605        case ENCODING_IEC61937: // same size as stereo PCM
606        case ENCODING_DEFAULT:
607            return true;
608        case ENCODING_AC3:
609        case ENCODING_E_AC3:
610        case ENCODING_E_AC3_JOC:
611        case ENCODING_DTS:
612        case ENCODING_DTS_HD:
613        case ENCODING_MP3:
614        case ENCODING_AAC_LC:
615        case ENCODING_AAC_HE_V1:
616        case ENCODING_AAC_HE_V2:
617        case ENCODING_AAC_ELD:
618        case ENCODING_AAC_XHE:
619        case ENCODING_AC4:
620            return false;
621        case ENCODING_INVALID:
622        default:
623            throw new IllegalArgumentException("Bad audio format " + audioFormat);
624        }
625    }
626    /**
627     * Returns an array of public encoding values extracted from an array of
628     * encoding values.
629     * @hide
630     */
631    public static int[] filterPublicFormats(int[] formats) {
632        if (formats == null) {
633            return null;
634        }
635        int[] myCopy = Arrays.copyOf(formats, formats.length);
636        int size = 0;
637        for (int i = 0; i < myCopy.length; i++) {
638            if (isPublicEncoding(myCopy[i])) {
639                if (size != i) {
640                    myCopy[size] = myCopy[i];
641                }
642                size++;
643            }
644        }
645        return Arrays.copyOf(myCopy, size);
646    }
647
648    /** @removed */
649    public AudioFormat()
650    {
651        throw new UnsupportedOperationException("There is no valid usage of this constructor");
652    }
653
654    /**
655     * Private constructor with an ignored argument to differentiate from the removed default ctor
656     * @param ignoredArgument
657     */
658    private AudioFormat(int ignoredArgument) {
659    }
660
661    /**
662     * Constructor used by the JNI.  Parameters are not checked for validity.
663     */
664    // Update sound trigger JNI in core/jni/android_hardware_SoundTrigger.cpp when modifying this
665    // constructor
666    private AudioFormat(int encoding, int sampleRate, int channelMask, int channelIndexMask) {
667        mEncoding = encoding;
668        mSampleRate = sampleRate;
669        mChannelMask = channelMask;
670        mChannelIndexMask = channelIndexMask;
671        mPropertySetMask = AUDIO_FORMAT_HAS_PROPERTY_ENCODING |
672                AUDIO_FORMAT_HAS_PROPERTY_SAMPLE_RATE |
673                AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_MASK |
674                AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_INDEX_MASK;
675    }
676
677    /** @hide */
678    public final static int AUDIO_FORMAT_HAS_PROPERTY_NONE = 0x0;
679    /** @hide */
680    public final static int AUDIO_FORMAT_HAS_PROPERTY_ENCODING = 0x1 << 0;
681    /** @hide */
682    public final static int AUDIO_FORMAT_HAS_PROPERTY_SAMPLE_RATE = 0x1 << 1;
683    /** @hide */
684    public final static int AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_MASK = 0x1 << 2;
685    /** @hide */
686    public final static int AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_INDEX_MASK = 0x1 << 3;
687
688    private int mEncoding;
689    private int mSampleRate;
690    private int mChannelMask;
691    private int mChannelIndexMask;
692    private int mPropertySetMask;
693
694    /**
695     * Return the encoding.
696     * See the section on <a href="#encoding">encodings</a> for more information about the different
697     * types of supported audio encoding.
698     * @return one of the values that can be set in {@link Builder#setEncoding(int)} or
699     * {@link AudioFormat#ENCODING_INVALID} if not set.
700     */
701    public int getEncoding() {
702        if ((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_ENCODING) == 0) {
703            return ENCODING_INVALID;
704        }
705        return mEncoding;
706    }
707
708    /**
709     * Return the sample rate.
710     * @return one of the values that can be set in {@link Builder#setSampleRate(int)} or
711     * {@link #SAMPLE_RATE_UNSPECIFIED} if not set.
712     */
713    public int getSampleRate() {
714        return mSampleRate;
715    }
716
717    /**
718     * Return the channel mask.
719     * See the section on <a href="#channelMask">channel masks</a> for more information about
720     * the difference between index-based masks(as returned by {@link #getChannelIndexMask()}) and
721     * the position-based mask returned by this function.
722     * @return one of the values that can be set in {@link Builder#setChannelMask(int)} or
723     * {@link AudioFormat#CHANNEL_INVALID} if not set.
724     */
725    public int getChannelMask() {
726        if ((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_MASK) == 0) {
727            return CHANNEL_INVALID;
728        }
729        return mChannelMask;
730    }
731
732    /**
733     * Return the channel index mask.
734     * See the section on <a href="#channelMask">channel masks</a> for more information about
735     * the difference between index-based masks, and position-based masks (as returned
736     * by {@link #getChannelMask()}).
737     * @return one of the values that can be set in {@link Builder#setChannelIndexMask(int)} or
738     * {@link AudioFormat#CHANNEL_INVALID} if not set or an invalid mask was used.
739     */
740    public int getChannelIndexMask() {
741        if ((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_INDEX_MASK) == 0) {
742            return CHANNEL_INVALID;
743        }
744        return mChannelIndexMask;
745    }
746
747    /**
748     * Return the channel count.
749     * @return the channel count derived from the channel position mask or the channel index mask.
750     * Zero is returned if both the channel position mask and the channel index mask are not set.
751     */
752    public int getChannelCount() {
753        final int channelIndexCount = Integer.bitCount(getChannelIndexMask());
754        int channelCount = channelCountFromOutChannelMask(getChannelMask());
755        if (channelCount == 0) {
756            channelCount = channelIndexCount;
757        } else if (channelCount != channelIndexCount && channelIndexCount != 0) {
758            channelCount = 0; // position and index channel count mismatch
759        }
760        return channelCount;
761    }
762
763    /** @hide */
764    public int getPropertySetMask() {
765        return mPropertySetMask;
766    }
767
768    /** @hide */
769    public String toLogFriendlyString() {
770        return String.format("%dch %dHz %s",
771                getChannelCount(), mSampleRate, toLogFriendlyEncoding(mEncoding));
772    }
773
774    /**
775     * Builder class for {@link AudioFormat} objects.
776     * Use this class to configure and create an AudioFormat instance. By setting format
777     * characteristics such as audio encoding, channel mask or sample rate, you indicate which
778     * of those are to vary from the default behavior on this device wherever this audio format
779     * is used. See {@link AudioFormat} for a complete description of the different parameters that
780     * can be used to configure an <code>AudioFormat</code> instance.
781     * <p>{@link AudioFormat} is for instance used in
782     * {@link AudioTrack#AudioTrack(AudioAttributes, AudioFormat, int, int, int)}. In this
783     * constructor, every format characteristic set on the <code>Builder</code> (e.g. with
784     * {@link #setSampleRate(int)}) will alter the default values used by an
785     * <code>AudioTrack</code>. In this case for audio playback with <code>AudioTrack</code>, the
786     * sample rate set in the <code>Builder</code> would override the platform output sample rate
787     * which would otherwise be selected by default.
788     */
789    public static class Builder {
790        private int mEncoding = ENCODING_INVALID;
791        private int mSampleRate = SAMPLE_RATE_UNSPECIFIED;
792        private int mChannelMask = CHANNEL_INVALID;
793        private int mChannelIndexMask = 0;
794        private int mPropertySetMask = AUDIO_FORMAT_HAS_PROPERTY_NONE;
795
796        /**
797         * Constructs a new Builder with none of the format characteristics set.
798         */
799        public Builder() {
800        }
801
802        /**
803         * Constructs a new Builder from a given {@link AudioFormat}.
804         * @param af the {@link AudioFormat} object whose data will be reused in the new Builder.
805         */
806        public Builder(AudioFormat af) {
807            mEncoding = af.mEncoding;
808            mSampleRate = af.mSampleRate;
809            mChannelMask = af.mChannelMask;
810            mChannelIndexMask = af.mChannelIndexMask;
811            mPropertySetMask = af.mPropertySetMask;
812        }
813
814        /**
815         * Combines all of the format characteristics that have been set and return a new
816         * {@link AudioFormat} object.
817         * @return a new {@link AudioFormat} object
818         */
819        public AudioFormat build() {
820            AudioFormat af = new AudioFormat(1980/*ignored*/);
821            af.mEncoding = mEncoding;
822            // not calling setSampleRate is equivalent to calling
823            // setSampleRate(SAMPLE_RATE_UNSPECIFIED)
824            af.mSampleRate = mSampleRate;
825            af.mChannelMask = mChannelMask;
826            af.mChannelIndexMask = mChannelIndexMask;
827            af.mPropertySetMask = mPropertySetMask;
828            return af;
829        }
830
831        /**
832         * Sets the data encoding format.
833         * @param encoding the specified encoding or default.
834         * @return the same Builder instance.
835         * @throws java.lang.IllegalArgumentException
836         */
837        public Builder setEncoding(@Encoding int encoding) throws IllegalArgumentException {
838            switch (encoding) {
839                case ENCODING_DEFAULT:
840                    mEncoding = ENCODING_PCM_16BIT;
841                    break;
842                case ENCODING_PCM_8BIT:
843                case ENCODING_PCM_16BIT:
844                case ENCODING_PCM_FLOAT:
845                case ENCODING_AC3:
846                case ENCODING_E_AC3:
847                case ENCODING_E_AC3_JOC:
848                case ENCODING_DTS:
849                case ENCODING_DTS_HD:
850                case ENCODING_IEC61937:
851                case ENCODING_MP3:
852                case ENCODING_AAC_LC:
853                case ENCODING_AAC_HE_V1:
854                case ENCODING_AAC_HE_V2:
855                case ENCODING_AAC_ELD:
856                case ENCODING_AAC_XHE:
857                case ENCODING_AC4:
858                    mEncoding = encoding;
859                    break;
860                case ENCODING_INVALID:
861                default:
862                    throw new IllegalArgumentException("Invalid encoding " + encoding);
863            }
864            mPropertySetMask |= AUDIO_FORMAT_HAS_PROPERTY_ENCODING;
865            return this;
866        }
867
868        /**
869         * Sets the channel position mask.
870         * The channel position mask specifies the association between audio samples in a frame
871         * with named endpoint channels. The samples in the frame correspond to the
872         * named set bits in the channel position mask, in ascending bit order.
873         * See {@link #setChannelIndexMask(int)} to specify channels
874         * based on endpoint numbered channels. This <a href="#channelPositionMask>description of
875         * channel position masks</a> covers the concept in more details.
876         * @param channelMask describes the configuration of the audio channels.
877         *    <p> For output, the channelMask can be an OR-ed combination of
878         *    channel position masks, e.g.
879         *    {@link AudioFormat#CHANNEL_OUT_FRONT_LEFT},
880         *    {@link AudioFormat#CHANNEL_OUT_FRONT_RIGHT},
881         *    {@link AudioFormat#CHANNEL_OUT_FRONT_CENTER},
882         *    {@link AudioFormat#CHANNEL_OUT_LOW_FREQUENCY}
883         *    {@link AudioFormat#CHANNEL_OUT_BACK_LEFT},
884         *    {@link AudioFormat#CHANNEL_OUT_BACK_RIGHT},
885         *    {@link AudioFormat#CHANNEL_OUT_BACK_CENTER},
886         *    {@link AudioFormat#CHANNEL_OUT_SIDE_LEFT},
887         *    {@link AudioFormat#CHANNEL_OUT_SIDE_RIGHT}.
888         *    <p> For a valid {@link AudioTrack} channel position mask,
889         *    the following conditions apply:
890         *    <br> (1) at most eight channel positions may be used;
891         *    <br> (2) right/left pairs should be matched.
892         *    <p> For input or {@link AudioRecord}, the mask should be
893         *    {@link AudioFormat#CHANNEL_IN_MONO} or
894         *    {@link AudioFormat#CHANNEL_IN_STEREO}.  {@link AudioFormat#CHANNEL_IN_MONO} is
895         *    guaranteed to work on all devices.
896         * @return the same <code>Builder</code> instance.
897         * @throws IllegalArgumentException if the channel mask is invalid or
898         *    if both channel index mask and channel position mask
899         *    are specified but do not have the same channel count.
900         */
901        public @NonNull Builder setChannelMask(int channelMask) {
902            if (channelMask == CHANNEL_INVALID) {
903                throw new IllegalArgumentException("Invalid zero channel mask");
904            } else if (/* channelMask != 0 && */ mChannelIndexMask != 0 &&
905                    Integer.bitCount(channelMask) != Integer.bitCount(mChannelIndexMask)) {
906                throw new IllegalArgumentException("Mismatched channel count for mask " +
907                        Integer.toHexString(channelMask).toUpperCase());
908            }
909            mChannelMask = channelMask;
910            mPropertySetMask |= AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_MASK;
911            return this;
912        }
913
914        /**
915         * Sets the channel index mask.
916         * A channel index mask specifies the association of audio samples in the frame
917         * with numbered endpoint channels. The i-th bit in the channel index
918         * mask corresponds to the i-th endpoint channel.
919         * For example, an endpoint with four channels is represented
920         * as index mask bits 0 through 3. This <a href="#channelIndexMask>description of channel
921         * index masks</a> covers the concept in more details.
922         * See {@link #setChannelMask(int)} for a positional mask interpretation.
923         * <p> Both {@link AudioTrack} and {@link AudioRecord} support
924         * a channel index mask.
925         * If a channel index mask is specified it is used,
926         * otherwise the channel position mask specified
927         * by <code>setChannelMask</code> is used.
928         * For <code>AudioTrack</code> and <code>AudioRecord</code>,
929         * a channel position mask is not required if a channel index mask is specified.
930         *
931         * @param channelIndexMask describes the configuration of the audio channels.
932         *    <p> For output, the <code>channelIndexMask</code> is an OR-ed combination of
933         *    bits representing the mapping of <code>AudioTrack</code> write samples
934         *    to output sink channels.
935         *    For example, a mask of <code>0xa</code>, or binary <code>1010</code>,
936         *    means the <code>AudioTrack</code> write frame consists of two samples,
937         *    which are routed to the second and the fourth channels of the output sink.
938         *    Unmatched output sink channels are zero filled and unmatched
939         *    <code>AudioTrack</code> write samples are dropped.
940         *    <p> For input, the <code>channelIndexMask</code> is an OR-ed combination of
941         *    bits representing the mapping of input source channels to
942         *    <code>AudioRecord</code> read samples.
943         *    For example, a mask of <code>0x5</code>, or binary
944         *    <code>101</code>, will read from the first and third channel of the input
945         *    source device and store them in the first and second sample of the
946         *    <code>AudioRecord</code> read frame.
947         *    Unmatched input source channels are dropped and
948         *    unmatched <code>AudioRecord</code> read samples are zero filled.
949         * @return the same <code>Builder</code> instance.
950         * @throws IllegalArgumentException if the channel index mask is invalid or
951         *    if both channel index mask and channel position mask
952         *    are specified but do not have the same channel count.
953         */
954        public @NonNull Builder setChannelIndexMask(int channelIndexMask) {
955            if (channelIndexMask == 0) {
956                throw new IllegalArgumentException("Invalid zero channel index mask");
957            } else if (/* channelIndexMask != 0 && */ mChannelMask != 0 &&
958                    Integer.bitCount(channelIndexMask) != Integer.bitCount(mChannelMask)) {
959                throw new IllegalArgumentException("Mismatched channel count for index mask " +
960                        Integer.toHexString(channelIndexMask).toUpperCase());
961            }
962            mChannelIndexMask = channelIndexMask;
963            mPropertySetMask |= AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_INDEX_MASK;
964            return this;
965        }
966
967        /**
968         * Sets the sample rate.
969         * @param sampleRate the sample rate expressed in Hz
970         * @return the same Builder instance.
971         * @throws java.lang.IllegalArgumentException
972         */
973        public Builder setSampleRate(int sampleRate) throws IllegalArgumentException {
974            // TODO Consider whether to keep the MIN and MAX range checks here.
975            // It is not necessary and poses the problem of defining the limits independently from
976            // native implementation or platform capabilities.
977            if (((sampleRate < SAMPLE_RATE_HZ_MIN) || (sampleRate > SAMPLE_RATE_HZ_MAX)) &&
978                    sampleRate != SAMPLE_RATE_UNSPECIFIED) {
979                throw new IllegalArgumentException("Invalid sample rate " + sampleRate);
980            }
981            mSampleRate = sampleRate;
982            mPropertySetMask |= AUDIO_FORMAT_HAS_PROPERTY_SAMPLE_RATE;
983            return this;
984        }
985    }
986
987    @Override
988    public boolean equals(Object o) {
989        if (this == o) return true;
990        if (o == null || getClass() != o.getClass()) return false;
991
992        AudioFormat that = (AudioFormat) o;
993
994        if (mPropertySetMask != that.mPropertySetMask) return false;
995
996        // return false if any of the properties is set and the values differ
997        return !((((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_ENCODING) != 0)
998                            && (mEncoding != that.mEncoding))
999                    || (((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_SAMPLE_RATE) != 0)
1000                            && (mSampleRate != that.mSampleRate))
1001                    || (((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_MASK) != 0)
1002                            && (mChannelMask != that.mChannelMask))
1003                    || (((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_INDEX_MASK) != 0)
1004                            && (mChannelIndexMask != that.mChannelIndexMask)));
1005    }
1006
1007    @Override
1008    public int hashCode() {
1009        return Objects.hash(mPropertySetMask, mSampleRate, mEncoding, mChannelMask,
1010                mChannelIndexMask);
1011    }
1012
1013    @Override
1014    public int describeContents() {
1015        return 0;
1016    }
1017
1018    @Override
1019    public void writeToParcel(Parcel dest, int flags) {
1020        dest.writeInt(mPropertySetMask);
1021        dest.writeInt(mEncoding);
1022        dest.writeInt(mSampleRate);
1023        dest.writeInt(mChannelMask);
1024        dest.writeInt(mChannelIndexMask);
1025    }
1026
1027    private AudioFormat(Parcel in) {
1028        mPropertySetMask = in.readInt();
1029        mEncoding = in.readInt();
1030        mSampleRate = in.readInt();
1031        mChannelMask = in.readInt();
1032        mChannelIndexMask = in.readInt();
1033    }
1034
1035    public static final Parcelable.Creator<AudioFormat> CREATOR =
1036            new Parcelable.Creator<AudioFormat>() {
1037        public AudioFormat createFromParcel(Parcel p) {
1038            return new AudioFormat(p);
1039        }
1040        public AudioFormat[] newArray(int size) {
1041            return new AudioFormat[size];
1042        }
1043    };
1044
1045    @Override
1046    public String toString () {
1047        return new String("AudioFormat:"
1048                + " props=" + mPropertySetMask
1049                + " enc=" + mEncoding
1050                + " chan=0x" + Integer.toHexString(mChannelMask).toUpperCase()
1051                + " chan_index=0x" + Integer.toHexString(mChannelIndexMask).toUpperCase()
1052                + " rate=" + mSampleRate);
1053    }
1054
1055    /** @hide */
1056    @IntDef(flag = false, prefix = "ENCODING", value = {
1057        ENCODING_DEFAULT,
1058        ENCODING_PCM_8BIT,
1059        ENCODING_PCM_16BIT,
1060        ENCODING_PCM_FLOAT,
1061        ENCODING_AC3,
1062        ENCODING_E_AC3,
1063        ENCODING_E_AC3_JOC,
1064        ENCODING_DTS,
1065        ENCODING_DTS_HD,
1066        ENCODING_IEC61937,
1067        ENCODING_AAC_HE_V1,
1068        ENCODING_AAC_HE_V2,
1069        ENCODING_AAC_LC,
1070        ENCODING_AAC_ELD,
1071        ENCODING_AAC_XHE,
1072        ENCODING_AC4 }
1073    )
1074    @Retention(RetentionPolicy.SOURCE)
1075    public @interface Encoding {}
1076
1077    /** @hide */
1078    public static final int[] SURROUND_SOUND_ENCODING = {
1079            ENCODING_AC3,
1080            ENCODING_E_AC3,
1081            ENCODING_DTS,
1082            ENCODING_DTS_HD,
1083            ENCODING_AAC_LC,
1084            ENCODING_DOLBY_TRUEHD,
1085            ENCODING_E_AC3_JOC,
1086    };
1087
1088    /** @hide */
1089    @IntDef(flag = false, prefix = "ENCODING", value = {
1090            ENCODING_AC3,
1091            ENCODING_E_AC3,
1092            ENCODING_DTS,
1093            ENCODING_DTS_HD,
1094            ENCODING_AAC_LC,
1095            ENCODING_DOLBY_TRUEHD,
1096            ENCODING_E_AC3_JOC }
1097    )
1098    @Retention(RetentionPolicy.SOURCE)
1099    public @interface SurroundSoundEncoding {}
1100
1101    /**
1102     * @hide
1103     *
1104     * Return default name for a surround format. This is not an International name.
1105     * It is just a default to use if an international name is not available.
1106     *
1107     * @param audioFormat a surround format
1108     * @return short default name for the format, eg. “AC3” for ENCODING_AC3.
1109     */
1110    public static String toDisplayName(@SurroundSoundEncoding int audioFormat) {
1111        switch (audioFormat) {
1112            case ENCODING_AC3:
1113                return "Dolby Digital (AC3)";
1114            case ENCODING_E_AC3:
1115                return "Dolby Digital Plus (E_AC3)";
1116            case ENCODING_DTS:
1117                return "DTS";
1118            case ENCODING_DTS_HD:
1119                return "DTS HD";
1120            case ENCODING_AAC_LC:
1121                return "AAC";
1122            case ENCODING_DOLBY_TRUEHD:
1123                return "Dolby TrueHD";
1124            case ENCODING_E_AC3_JOC:
1125                return "Dolby Atmos";
1126            default:
1127                return "Unknown surround sound format";
1128        }
1129    }
1130
1131}
1132