Torne (Richard Coles) | 5821806 | 2012-11-14 11:43:16 +0000 | [diff] [blame] | 1 | /* Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| 2 | * Use of this source code is governed by a BSD-style license that can be |
| 3 | * found in the LICENSE file. |
| 4 | */ |
| 5 | |
Torne (Richard Coles) | 5d1f7b1 | 2014-02-21 12:16:55 +0000 | [diff] [blame] | 6 | /* From ppb_audio_config.idl modified Fri Jan 24 16:19:35 2014. */ |
Torne (Richard Coles) | 5821806 | 2012-11-14 11:43:16 +0000 | [diff] [blame] | 7 | |
| 8 | #ifndef PPAPI_C_PPB_AUDIO_CONFIG_H_ |
| 9 | #define PPAPI_C_PPB_AUDIO_CONFIG_H_ |
| 10 | |
| 11 | #include "ppapi/c/pp_bool.h" |
| 12 | #include "ppapi/c/pp_instance.h" |
| 13 | #include "ppapi/c/pp_macros.h" |
| 14 | #include "ppapi/c/pp_resource.h" |
| 15 | #include "ppapi/c/pp_stdint.h" |
| 16 | |
| 17 | #define PPB_AUDIO_CONFIG_INTERFACE_1_0 "PPB_AudioConfig;1.0" |
| 18 | #define PPB_AUDIO_CONFIG_INTERFACE_1_1 "PPB_AudioConfig;1.1" |
| 19 | #define PPB_AUDIO_CONFIG_INTERFACE PPB_AUDIO_CONFIG_INTERFACE_1_1 |
| 20 | |
| 21 | /** |
| 22 | * @file |
| 23 | * This file defines the PPB_AudioConfig interface for establishing an |
| 24 | * audio configuration resource within the browser. |
| 25 | */ |
| 26 | |
| 27 | |
| 28 | /** |
| 29 | * @addtogroup Enums |
| 30 | * @{ |
| 31 | */ |
| 32 | /** |
| 33 | * This enumeration contains audio frame count constants. |
| 34 | * <code>PP_AUDIOMINSAMPLEFRAMECOUNT</code> is the minimum possible frame |
| 35 | * count. <code>PP_AUDIOMAXSAMPLEFRAMECOUNT</code> is the maximum possible |
| 36 | * frame count. |
| 37 | */ |
| 38 | enum { |
| 39 | PP_AUDIOMINSAMPLEFRAMECOUNT = 64, |
| 40 | PP_AUDIOMAXSAMPLEFRAMECOUNT = 32768 |
| 41 | }; |
| 42 | |
| 43 | /** |
| 44 | * PP_AudioSampleRate is an enumeration of the different audio sampling rates. |
| 45 | * <code>PP_AUDIOSAMPLERATE_44100</code> is the sample rate used on CDs and |
| 46 | * <code>PP_AUDIOSAMPLERATE_48000</code> is the sample rate used on DVDs and |
| 47 | * Digital Audio Tapes. |
| 48 | */ |
| 49 | typedef enum { |
| 50 | PP_AUDIOSAMPLERATE_NONE = 0, |
| 51 | PP_AUDIOSAMPLERATE_44100 = 44100, |
| 52 | PP_AUDIOSAMPLERATE_48000 = 48000 |
| 53 | } PP_AudioSampleRate; |
| 54 | PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_AudioSampleRate, 4); |
| 55 | /** |
| 56 | * @} |
| 57 | */ |
| 58 | |
| 59 | /** |
| 60 | * @addtogroup Interfaces |
| 61 | * @{ |
| 62 | */ |
| 63 | /** |
| 64 | * The <code>PPB_AudioConfig</code> interface contains pointers to several |
| 65 | * functions for establishing your audio configuration within the browser. |
| 66 | * This interface only supports 16-bit stereo output. |
| 67 | * |
| 68 | * Refer to the |
Torne (Richard Coles) | 5d1f7b1 | 2014-02-21 12:16:55 +0000 | [diff] [blame] | 69 | * <a href="/native-client/devguide/coding/audio.html">Audio |
Torne (Richard Coles) | 5821806 | 2012-11-14 11:43:16 +0000 | [diff] [blame] | 70 | * </a> chapter in the Developer's Guide for information on using this |
| 71 | * interface. |
| 72 | */ |
| 73 | struct PPB_AudioConfig_1_1 { |
| 74 | /** |
| 75 | * CreateStereo16bit() creates a 16 bit audio configuration resource. The |
| 76 | * <code>sample_rate</code> should be the result of calling |
| 77 | * <code>RecommendSampleRate</code> and <code>sample_frame_count</code> should |
| 78 | * be the result of calling <code>RecommendSampleFrameCount</code>. If the |
| 79 | * sample frame count or bit rate isn't supported, this function will fail and |
| 80 | * return a null resource. |
| 81 | * |
| 82 | * A single sample frame on a stereo device means one value for the left |
| 83 | * channel and one value for the right channel. |
| 84 | * |
| 85 | * Buffer layout for a stereo int16 configuration: |
| 86 | * <code>int16_t *buffer16;</code> |
| 87 | * <code>buffer16[0]</code> is the first left channel sample. |
| 88 | * <code>buffer16[1]</code> is the first right channel sample. |
| 89 | * <code>buffer16[2]</code> is the second left channel sample. |
| 90 | * <code>buffer16[3]</code> is the second right channel sample. |
| 91 | * ... |
| 92 | * <code>buffer16[2 * (sample_frame_count - 1)]</code> is the last left |
| 93 | * channel sample. |
| 94 | * <code>buffer16[2 * (sample_frame_count - 1) + 1]</code> is the last |
| 95 | * right channel sample. |
| 96 | * Data will always be in the native endian format of the platform. |
| 97 | * |
| 98 | * @param[in] instance A <code>PP_Instance</code> identifying one instance |
| 99 | * of a module. |
| 100 | * @param[in] sample_rate A <code>PP_AudioSampleRate</code> which is either |
| 101 | * <code>PP_AUDIOSAMPLERATE_44100</code> or |
| 102 | * <code>PP_AUDIOSAMPLERATE_48000</code>. |
| 103 | * @param[in] sample_frame_count A <code>uint32_t</code> frame count returned |
| 104 | * from the <code>RecommendSampleFrameCount</code> function. |
| 105 | * |
| 106 | * @return A <code>PP_Resource</code> containing the |
| 107 | * <code>PPB_Audio_Config</code> if successful or a null resource if the |
| 108 | * sample frame count or bit rate are not supported. |
| 109 | */ |
| 110 | PP_Resource (*CreateStereo16Bit)(PP_Instance instance, |
| 111 | PP_AudioSampleRate sample_rate, |
| 112 | uint32_t sample_frame_count); |
| 113 | /** |
| 114 | * RecommendSampleFrameCount() returns the supported sample frame count |
| 115 | * closest to the requested count. The sample frame count determines the |
| 116 | * overall latency of audio. Since one "frame" is always buffered in advance, |
| 117 | * smaller frame counts will yield lower latency, but higher CPU utilization. |
| 118 | * |
| 119 | * Supported sample frame counts will vary by hardware and system (consider |
| 120 | * that the local system might be anywhere from a cell phone or a high-end |
| 121 | * audio workstation). Sample counts less than |
| 122 | * <code>PP_AUDIOMINSAMPLEFRAMECOUNT</code> and greater than |
| 123 | * <code>PP_AUDIOMAXSAMPLEFRAMECOUNT</code> are never supported on any |
| 124 | * system, but values in between aren't necessarily valid. This function |
| 125 | * will return a supported count closest to the requested frame count. |
| 126 | * |
| 127 | * RecommendSampleFrameCount() result is intended for audio output devices. |
| 128 | * |
| 129 | * @param[in] instance |
| 130 | * @param[in] sample_rate A <code>PP_AudioSampleRate</code> which is either |
| 131 | * <code>PP_AUDIOSAMPLERATE_44100</code> or |
| 132 | * <code>PP_AUDIOSAMPLERATE_48000.</code> |
| 133 | * @param[in] requested_sample_frame_count A <code>uint_32t</code> requested |
| 134 | * frame count. |
| 135 | * |
| 136 | * @return A <code>uint32_t</code> containing the recommended sample frame |
| 137 | * count if successful. |
| 138 | */ |
| 139 | uint32_t (*RecommendSampleFrameCount)( |
| 140 | PP_Instance instance, |
| 141 | PP_AudioSampleRate sample_rate, |
| 142 | uint32_t requested_sample_frame_count); |
| 143 | /** |
| 144 | * IsAudioConfig() determines if the given resource is a |
| 145 | * <code>PPB_Audio_Config</code>. |
| 146 | * |
| 147 | * @param[in] resource A <code>PP_Resource</code> corresponding to an audio |
| 148 | * config resource. |
| 149 | * |
| 150 | * @return A <code>PP_Bool</code> containing <code>PP_TRUE</code> if the given |
| 151 | * resource is an <code>AudioConfig</code> resource, otherwise |
| 152 | * <code>PP_FALSE</code>. |
| 153 | */ |
| 154 | PP_Bool (*IsAudioConfig)(PP_Resource resource); |
| 155 | /** |
| 156 | * GetSampleRate() returns the sample rate for the given |
| 157 | * <code>PPB_Audio_Config</code>. |
| 158 | * |
| 159 | * @param[in] config A <code>PP_Resource</code> corresponding to a |
| 160 | * <code>PPB_Audio_Config</code>. |
| 161 | * |
| 162 | * @return A <code>PP_AudioSampleRate</code> containing sample rate or |
| 163 | * <code>PP_AUDIOSAMPLERATE_NONE</code> if the resource is invalid. |
| 164 | */ |
| 165 | PP_AudioSampleRate (*GetSampleRate)(PP_Resource config); |
| 166 | /** |
| 167 | * GetSampleFrameCount() returns the sample frame count for the given |
| 168 | * <code>PPB_Audio_Config</code>. |
| 169 | * |
| 170 | * @param[in] config A <code>PP_Resource</code> corresponding to an audio |
| 171 | * config resource. |
| 172 | * |
| 173 | * @return A <code>uint32_t</code> containing sample frame count or |
| 174 | * 0 if the resource is invalid. Refer to |
| 175 | * RecommendSampleFrameCount() for more on sample frame counts. |
| 176 | */ |
| 177 | uint32_t (*GetSampleFrameCount)(PP_Resource config); |
| 178 | /** |
| 179 | * RecommendSampleRate() returns the native sample rate that the browser |
| 180 | * is using in the backend. Applications that use the recommended sample |
| 181 | * rate will have potentially better latency and fidelity. The return value |
Torne (Richard Coles) | c2e0dbd | 2013-05-09 18:35:53 +0100 | [diff] [blame] | 182 | * is intended for audio output devices. If the output sample rate cannot be |
Torne (Richard Coles) | 5821806 | 2012-11-14 11:43:16 +0000 | [diff] [blame] | 183 | * determined, this function can return PP_AUDIOSAMPLERATE_NONE. |
| 184 | * |
| 185 | * @param[in] instance |
| 186 | * |
| 187 | * @return A <code>uint32_t</code> containing the recommended sample frame |
| 188 | * count if successful. |
| 189 | */ |
| 190 | PP_AudioSampleRate (*RecommendSampleRate)(PP_Instance instance); |
| 191 | }; |
| 192 | |
| 193 | typedef struct PPB_AudioConfig_1_1 PPB_AudioConfig; |
| 194 | |
| 195 | struct PPB_AudioConfig_1_0 { |
| 196 | PP_Resource (*CreateStereo16Bit)(PP_Instance instance, |
| 197 | PP_AudioSampleRate sample_rate, |
| 198 | uint32_t sample_frame_count); |
| 199 | uint32_t (*RecommendSampleFrameCount)( |
| 200 | PP_AudioSampleRate sample_rate, |
| 201 | uint32_t requested_sample_frame_count); |
| 202 | PP_Bool (*IsAudioConfig)(PP_Resource resource); |
| 203 | PP_AudioSampleRate (*GetSampleRate)(PP_Resource config); |
| 204 | uint32_t (*GetSampleFrameCount)(PP_Resource config); |
| 205 | }; |
| 206 | /** |
| 207 | * @} |
| 208 | */ |
| 209 | |
| 210 | #endif /* PPAPI_C_PPB_AUDIO_CONFIG_H_ */ |
| 211 | |