| 1 | /* |
| 2 | * This file is part of FFmpeg. |
| 3 | * |
| 4 | * FFmpeg is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 2.1 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * FFmpeg 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 GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with FFmpeg; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 17 | */ |
| 18 | |
| 19 | #ifndef AVDEVICE_AVDEVICE_H |
| 20 | #define AVDEVICE_AVDEVICE_H |
| 21 | |
| 22 | #include "version.h" |
| 23 | |
| 24 | /** |
| 25 | * @file |
| 26 | * @ingroup lavd |
| 27 | * Main libavdevice API header |
| 28 | */ |
| 29 | |
| 30 | /** |
| 31 | * @defgroup lavd Special devices muxing/demuxing library |
| 32 | * @{ |
| 33 | * Libavdevice is a complementary library to @ref libavf "libavformat". It |
| 34 | * provides various "special" platform-specific muxers and demuxers, e.g. for |
| 35 | * grabbing devices, audio capture and playback etc. As a consequence, the |
| 36 | * (de)muxers in libavdevice are of the AVFMT_NOFILE type (they use their own |
| 37 | * I/O functions). The filename passed to avformat_open_input() often does not |
| 38 | * refer to an actually existing file, but has some special device-specific |
| 39 | * meaning - e.g. for x11grab it is the display name. |
| 40 | * |
| 41 | * To use libavdevice, simply call avdevice_register_all() to register all |
| 42 | * compiled muxers and demuxers. They all use standard libavformat API. |
| 43 | * @} |
| 44 | */ |
| 45 | |
| 46 | #include "libavutil/log.h" |
| 47 | #include "libavutil/opt.h" |
| 48 | #include "libavutil/dict.h" |
| 49 | #include "libavformat/avformat.h" |
| 50 | |
| 51 | /** |
| 52 | * Return the LIBAVDEVICE_VERSION_INT constant. |
| 53 | */ |
| 54 | unsigned avdevice_version(void); |
| 55 | |
| 56 | /** |
| 57 | * Return the libavdevice build-time configuration. |
| 58 | */ |
| 59 | const char *avdevice_configuration(void); |
| 60 | |
| 61 | /** |
| 62 | * Return the libavdevice license. |
| 63 | */ |
| 64 | const char *avdevice_license(void); |
| 65 | |
| 66 | /** |
| 67 | * Initialize libavdevice and register all the input and output devices. |
| 68 | * @warning This function is not thread safe. |
| 69 | */ |
| 70 | void avdevice_register_all(void); |
| 71 | |
| 72 | /** |
| 73 | * Audio input devices iterator. |
| 74 | * |
| 75 | * If d is NULL, returns the first registered input audio/video device, |
| 76 | * if d is non-NULL, returns the next registered input audio/video device after d |
| 77 | * or NULL if d is the last one. |
| 78 | */ |
| 79 | AVInputFormat *av_input_audio_device_next(AVInputFormat *d); |
| 80 | |
| 81 | /** |
| 82 | * Video input devices iterator. |
| 83 | * |
| 84 | * If d is NULL, returns the first registered input audio/video device, |
| 85 | * if d is non-NULL, returns the next registered input audio/video device after d |
| 86 | * or NULL if d is the last one. |
| 87 | */ |
| 88 | AVInputFormat *av_input_video_device_next(AVInputFormat *d); |
| 89 | |
| 90 | /** |
| 91 | * Audio output devices iterator. |
| 92 | * |
| 93 | * If d is NULL, returns the first registered output audio/video device, |
| 94 | * if d is non-NULL, returns the next registered output audio/video device after d |
| 95 | * or NULL if d is the last one. |
| 96 | */ |
| 97 | AVOutputFormat *av_output_audio_device_next(AVOutputFormat *d); |
| 98 | |
| 99 | /** |
| 100 | * Video output devices iterator. |
| 101 | * |
| 102 | * If d is NULL, returns the first registered output audio/video device, |
| 103 | * if d is non-NULL, returns the next registered output audio/video device after d |
| 104 | * or NULL if d is the last one. |
| 105 | */ |
| 106 | AVOutputFormat *av_output_video_device_next(AVOutputFormat *d); |
| 107 | |
| 108 | typedef struct AVDeviceRect { |
| 109 | int x; /**< x coordinate of top left corner */ |
| 110 | int y; /**< y coordinate of top left corner */ |
| 111 | int width; /**< width */ |
| 112 | int height; /**< height */ |
| 113 | } AVDeviceRect; |
| 114 | |
| 115 | /** |
| 116 | * Message types used by avdevice_app_to_dev_control_message(). |
| 117 | */ |
| 118 | enum AVAppToDevMessageType { |
| 119 | /** |
| 120 | * Dummy message. |
| 121 | */ |
| 122 | AV_APP_TO_DEV_NONE = MKBETAG('N','O','N','E'), |
| 123 | |
| 124 | /** |
| 125 | * Window size change message. |
| 126 | * |
| 127 | * Message is sent to the device every time the application changes the size |
| 128 | * of the window device renders to. |
| 129 | * Message should also be sent right after window is created. |
| 130 | * |
| 131 | * data: AVDeviceRect: new window size. |
| 132 | */ |
| 133 | AV_APP_TO_DEV_WINDOW_SIZE = MKBETAG('G','E','O','M'), |
| 134 | |
| 135 | /** |
| 136 | * Repaint request message. |
| 137 | * |
| 138 | * Message is sent to the device when window has to be repainted. |
| 139 | * |
| 140 | * data: AVDeviceRect: area required to be repainted. |
| 141 | * NULL: whole area is required to be repainted. |
| 142 | */ |
| 143 | AV_APP_TO_DEV_WINDOW_REPAINT = MKBETAG('R','E','P','A'), |
| 144 | |
| 145 | /** |
| 146 | * Request pause/play. |
| 147 | * |
| 148 | * Application requests pause/unpause playback. |
| 149 | * Mostly usable with devices that have internal buffer. |
| 150 | * By default devices are not paused. |
| 151 | * |
| 152 | * data: NULL |
| 153 | */ |
| 154 | AV_APP_TO_DEV_PAUSE = MKBETAG('P', 'A', 'U', ' '), |
| 155 | AV_APP_TO_DEV_PLAY = MKBETAG('P', 'L', 'A', 'Y'), |
| 156 | AV_APP_TO_DEV_TOGGLE_PAUSE = MKBETAG('P', 'A', 'U', 'T'), |
| 157 | |
| 158 | /** |
| 159 | * Volume control message. |
| 160 | * |
| 161 | * Set volume level. It may be device-dependent if volume |
| 162 | * is changed per stream or system wide. Per stream volume |
| 163 | * change is expected when possible. |
| 164 | * |
| 165 | * data: double: new volume with range of 0.0 - 1.0. |
| 166 | */ |
| 167 | AV_APP_TO_DEV_SET_VOLUME = MKBETAG('S', 'V', 'O', 'L'), |
| 168 | |
| 169 | /** |
| 170 | * Mute control messages. |
| 171 | * |
| 172 | * Change mute state. It may be device-dependent if mute status |
| 173 | * is changed per stream or system wide. Per stream mute status |
| 174 | * change is expected when possible. |
| 175 | * |
| 176 | * data: NULL. |
| 177 | */ |
| 178 | AV_APP_TO_DEV_MUTE = MKBETAG(' ', 'M', 'U', 'T'), |
| 179 | AV_APP_TO_DEV_UNMUTE = MKBETAG('U', 'M', 'U', 'T'), |
| 180 | AV_APP_TO_DEV_TOGGLE_MUTE = MKBETAG('T', 'M', 'U', 'T'), |
| 181 | |
| 182 | /** |
| 183 | * Get volume/mute messages. |
| 184 | * |
| 185 | * Force the device to send AV_DEV_TO_APP_VOLUME_LEVEL_CHANGED or |
| 186 | * AV_DEV_TO_APP_MUTE_STATE_CHANGED command respectively. |
| 187 | * |
| 188 | * data: NULL. |
| 189 | */ |
| 190 | AV_APP_TO_DEV_GET_VOLUME = MKBETAG('G', 'V', 'O', 'L'), |
| 191 | AV_APP_TO_DEV_GET_MUTE = MKBETAG('G', 'M', 'U', 'T'), |
| 192 | }; |
| 193 | |
| 194 | /** |
| 195 | * Message types used by avdevice_dev_to_app_control_message(). |
| 196 | */ |
| 197 | enum AVDevToAppMessageType { |
| 198 | /** |
| 199 | * Dummy message. |
| 200 | */ |
| 201 | AV_DEV_TO_APP_NONE = MKBETAG('N','O','N','E'), |
| 202 | |
| 203 | /** |
| 204 | * Create window buffer message. |
| 205 | * |
| 206 | * Device requests to create a window buffer. Exact meaning is device- |
| 207 | * and application-dependent. Message is sent before rendering first |
| 208 | * frame and all one-shot initializations should be done here. |
| 209 | * Application is allowed to ignore preferred window buffer size. |
| 210 | * |
| 211 | * @note: Application is obligated to inform about window buffer size |
| 212 | * with AV_APP_TO_DEV_WINDOW_SIZE message. |
| 213 | * |
| 214 | * data: AVDeviceRect: preferred size of the window buffer. |
| 215 | * NULL: no preferred size of the window buffer. |
| 216 | */ |
| 217 | AV_DEV_TO_APP_CREATE_WINDOW_BUFFER = MKBETAG('B','C','R','E'), |
| 218 | |
| 219 | /** |
| 220 | * Prepare window buffer message. |
| 221 | * |
| 222 | * Device requests to prepare a window buffer for rendering. |
| 223 | * Exact meaning is device- and application-dependent. |
| 224 | * Message is sent before rendering of each frame. |
| 225 | * |
| 226 | * data: NULL. |
| 227 | */ |
| 228 | AV_DEV_TO_APP_PREPARE_WINDOW_BUFFER = MKBETAG('B','P','R','E'), |
| 229 | |
| 230 | /** |
| 231 | * Display window buffer message. |
| 232 | * |
| 233 | * Device requests to display a window buffer. |
| 234 | * Message is sent when new frame is ready to be displayed. |
| 235 | * Usually buffers need to be swapped in handler of this message. |
| 236 | * |
| 237 | * data: NULL. |
| 238 | */ |
| 239 | AV_DEV_TO_APP_DISPLAY_WINDOW_BUFFER = MKBETAG('B','D','I','S'), |
| 240 | |
| 241 | /** |
| 242 | * Destroy window buffer message. |
| 243 | * |
| 244 | * Device requests to destroy a window buffer. |
| 245 | * Message is sent when device is about to be destroyed and window |
| 246 | * buffer is not required anymore. |
| 247 | * |
| 248 | * data: NULL. |
| 249 | */ |
| 250 | AV_DEV_TO_APP_DESTROY_WINDOW_BUFFER = MKBETAG('B','D','E','S'), |
| 251 | |
| 252 | /** |
| 253 | * Buffer fullness status messages. |
| 254 | * |
| 255 | * Device signals buffer overflow/underflow. |
| 256 | * |
| 257 | * data: NULL. |
| 258 | */ |
| 259 | AV_DEV_TO_APP_BUFFER_OVERFLOW = MKBETAG('B','O','F','L'), |
| 260 | AV_DEV_TO_APP_BUFFER_UNDERFLOW = MKBETAG('B','U','F','L'), |
| 261 | |
| 262 | /** |
| 263 | * Buffer readable/writable. |
| 264 | * |
| 265 | * Device informs that buffer is readable/writable. |
| 266 | * When possible, device informs how many bytes can be read/write. |
| 267 | * |
| 268 | * @warning Device may not inform when number of bytes than can be read/write changes. |
| 269 | * |
| 270 | * data: int64_t: amount of bytes available to read/write. |
| 271 | * NULL: amount of bytes available to read/write is not known. |
| 272 | */ |
| 273 | AV_DEV_TO_APP_BUFFER_READABLE = MKBETAG('B','R','D',' '), |
| 274 | AV_DEV_TO_APP_BUFFER_WRITABLE = MKBETAG('B','W','R',' '), |
| 275 | |
| 276 | /** |
| 277 | * Mute state change message. |
| 278 | * |
| 279 | * Device informs that mute state has changed. |
| 280 | * |
| 281 | * data: int: 0 for not muted state, non-zero for muted state. |
| 282 | */ |
| 283 | AV_DEV_TO_APP_MUTE_STATE_CHANGED = MKBETAG('C','M','U','T'), |
| 284 | |
| 285 | /** |
| 286 | * Volume level change message. |
| 287 | * |
| 288 | * Device informs that volume level has changed. |
| 289 | * |
| 290 | * data: double: new volume with range of 0.0 - 1.0. |
| 291 | */ |
| 292 | AV_DEV_TO_APP_VOLUME_LEVEL_CHANGED = MKBETAG('C','V','O','L'), |
| 293 | }; |
| 294 | |
| 295 | /** |
| 296 | * Send control message from application to device. |
| 297 | * |
| 298 | * @param s device context. |
| 299 | * @param type message type. |
| 300 | * @param data message data. Exact type depends on message type. |
| 301 | * @param data_size size of message data. |
| 302 | * @return >= 0 on success, negative on error. |
| 303 | * AVERROR(ENOSYS) when device doesn't implement handler of the message. |
| 304 | */ |
| 305 | int avdevice_app_to_dev_control_message(struct AVFormatContext *s, |
| 306 | enum AVAppToDevMessageType type, |
| 307 | void *data, size_t data_size); |
| 308 | |
| 309 | /** |
| 310 | * Send control message from device to application. |
| 311 | * |
| 312 | * @param s device context. |
| 313 | * @param type message type. |
| 314 | * @param data message data. Can be NULL. |
| 315 | * @param data_size size of message data. |
| 316 | * @return >= 0 on success, negative on error. |
| 317 | * AVERROR(ENOSYS) when application doesn't implement handler of the message. |
| 318 | */ |
| 319 | int avdevice_dev_to_app_control_message(struct AVFormatContext *s, |
| 320 | enum AVDevToAppMessageType type, |
| 321 | void *data, size_t data_size); |
| 322 | |
| 323 | /** |
| 324 | * Following API allows user to probe device capabilities (supported codecs, |
| 325 | * pixel formats, sample formats, resolutions, channel counts, etc). |
| 326 | * It is build on top op AVOption API. |
| 327 | * Queried capabilities allows to set up converters of video or audio |
| 328 | * parameters that fit to the device. |
| 329 | * |
| 330 | * List of capabilities that can be queried: |
| 331 | * - Capabilities valid for both audio and video devices: |
| 332 | * - codec: supported audio/video codecs. |
| 333 | * type: AV_OPT_TYPE_INT (AVCodecID value) |
| 334 | * - Capabilities valid for audio devices: |
| 335 | * - sample_format: supported sample formats. |
| 336 | * type: AV_OPT_TYPE_INT (AVSampleFormat value) |
| 337 | * - sample_rate: supported sample rates. |
| 338 | * type: AV_OPT_TYPE_INT |
| 339 | * - channels: supported number of channels. |
| 340 | * type: AV_OPT_TYPE_INT |
| 341 | * - channel_layout: supported channel layouts. |
| 342 | * type: AV_OPT_TYPE_INT64 |
| 343 | * - Capabilities valid for video devices: |
| 344 | * - pixel_format: supported pixel formats. |
| 345 | * type: AV_OPT_TYPE_INT (AVPixelFormat value) |
| 346 | * - window_size: supported window sizes (describes size of the window size presented to the user). |
| 347 | * type: AV_OPT_TYPE_IMAGE_SIZE |
| 348 | * - frame_size: supported frame sizes (describes size of provided video frames). |
| 349 | * type: AV_OPT_TYPE_IMAGE_SIZE |
| 350 | * - fps: supported fps values |
| 351 | * type: AV_OPT_TYPE_RATIONAL |
| 352 | * |
| 353 | * Value of the capability may be set by user using av_opt_set() function |
| 354 | * and AVDeviceCapabilitiesQuery object. Following queries will |
| 355 | * limit results to the values matching already set capabilities. |
| 356 | * For example, setting a codec may impact number of formats or fps values |
| 357 | * returned during next query. Setting invalid value may limit results to zero. |
| 358 | * |
| 359 | * Example of the usage basing on opengl output device: |
| 360 | * |
| 361 | * @code |
| 362 | * AVFormatContext *oc = NULL; |
| 363 | * AVDeviceCapabilitiesQuery *caps = NULL; |
| 364 | * AVOptionRanges *ranges; |
| 365 | * int ret; |
| 366 | * |
| 367 | * if ((ret = avformat_alloc_output_context2(&oc, NULL, "opengl", NULL)) < 0) |
| 368 | * goto fail; |
| 369 | * if (avdevice_capabilities_create(&caps, oc, NULL) < 0) |
| 370 | * goto fail; |
| 371 | * |
| 372 | * //query codecs |
| 373 | * if (av_opt_query_ranges(&ranges, caps, "codec", AV_OPT_MULTI_COMPONENT_RANGE)) < 0) |
| 374 | * goto fail; |
| 375 | * //pick codec here and set it |
| 376 | * av_opt_set(caps, "codec", AV_CODEC_ID_RAWVIDEO, 0); |
| 377 | * |
| 378 | * //query format |
| 379 | * if (av_opt_query_ranges(&ranges, caps, "pixel_format", AV_OPT_MULTI_COMPONENT_RANGE)) < 0) |
| 380 | * goto fail; |
| 381 | * //pick format here and set it |
| 382 | * av_opt_set(caps, "pixel_format", AV_PIX_FMT_YUV420P, 0); |
| 383 | * |
| 384 | * //query and set more capabilities |
| 385 | * |
| 386 | * fail: |
| 387 | * //clean up code |
| 388 | * avdevice_capabilities_free(&query, oc); |
| 389 | * avformat_free_context(oc); |
| 390 | * @endcode |
| 391 | */ |
| 392 | |
| 393 | /** |
| 394 | * Structure describes device capabilities. |
| 395 | * |
| 396 | * It is used by devices in conjunction with av_device_capabilities AVOption table |
| 397 | * to implement capabilities probing API based on AVOption API. Should not be used directly. |
| 398 | */ |
| 399 | typedef struct AVDeviceCapabilitiesQuery { |
| 400 | const AVClass *av_class; |
| 401 | AVFormatContext *device_context; |
| 402 | enum AVCodecID codec; |
| 403 | enum AVSampleFormat sample_format; |
| 404 | enum AVPixelFormat pixel_format; |
| 405 | int sample_rate; |
| 406 | int channels; |
| 407 | int64_t channel_layout; |
| 408 | int window_width; |
| 409 | int window_height; |
| 410 | int frame_width; |
| 411 | int frame_height; |
| 412 | AVRational fps; |
| 413 | } AVDeviceCapabilitiesQuery; |
| 414 | |
| 415 | /** |
| 416 | * AVOption table used by devices to implement device capabilities API. Should not be used by a user. |
| 417 | */ |
| 418 | extern const AVOption av_device_capabilities[]; |
| 419 | |
| 420 | /** |
| 421 | * Initialize capabilities probing API based on AVOption API. |
| 422 | * |
| 423 | * avdevice_capabilities_free() must be called when query capabilities API is |
| 424 | * not used anymore. |
| 425 | * |
| 426 | * @param[out] caps Device capabilities data. Pointer to a NULL pointer must be passed. |
| 427 | * @param s Context of the device. |
| 428 | * @param device_options An AVDictionary filled with device-private options. |
| 429 | * On return this parameter will be destroyed and replaced with a dict |
| 430 | * containing options that were not found. May be NULL. |
| 431 | * The same options must be passed later to avformat_write_header() for output |
| 432 | * devices or avformat_open_input() for input devices, or at any other place |
| 433 | * that affects device-private options. |
| 434 | * |
| 435 | * @return >= 0 on success, negative otherwise. |
| 436 | */ |
| 437 | int avdevice_capabilities_create(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s, |
| 438 | AVDictionary **device_options); |
| 439 | |
| 440 | /** |
| 441 | * Free resources created by avdevice_capabilities_create() |
| 442 | * |
| 443 | * @param caps Device capabilities data to be freed. |
| 444 | * @param s Context of the device. |
| 445 | */ |
| 446 | void avdevice_capabilities_free(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s); |
| 447 | |
| 448 | /** |
| 449 | * Structure describes basic parameters of the device. |
| 450 | */ |
| 451 | typedef struct AVDeviceInfo { |
| 452 | char *device_name; /**< device name, format depends on device */ |
| 453 | char *device_description; /**< human friendly name */ |
| 454 | } AVDeviceInfo; |
| 455 | |
| 456 | /** |
| 457 | * List of devices. |
| 458 | */ |
| 459 | typedef struct AVDeviceInfoList { |
| 460 | AVDeviceInfo **devices; /**< list of autodetected devices */ |
| 461 | int nb_devices; /**< number of autodetected devices */ |
| 462 | int default_device; /**< index of default device or -1 if no default */ |
| 463 | } AVDeviceInfoList; |
| 464 | |
| 465 | /** |
| 466 | * List devices. |
| 467 | * |
| 468 | * Returns available device names and their parameters. |
| 469 | * |
| 470 | * @note: Some devices may accept system-dependent device names that cannot be |
| 471 | * autodetected. The list returned by this function cannot be assumed to |
| 472 | * be always completed. |
| 473 | * |
| 474 | * @param s device context. |
| 475 | * @param[out] device_list list of autodetected devices. |
| 476 | * @return count of autodetected devices, negative on error. |
| 477 | */ |
| 478 | int avdevice_list_devices(struct AVFormatContext *s, AVDeviceInfoList **device_list); |
| 479 | |
| 480 | /** |
| 481 | * Convenient function to free result of avdevice_list_devices(). |
| 482 | * |
| 483 | * @param devices device list to be freed. |
| 484 | */ |
| 485 | void avdevice_free_list_devices(AVDeviceInfoList **device_list); |
| 486 | |
| 487 | #endif /* AVDEVICE_AVDEVICE_H */ |