hwcontext.h 22 KB

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  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. #ifndef AVUTIL_HWCONTEXT_H
  19. #define AVUTIL_HWCONTEXT_H
  20. #include "buffer.h"
  21. #include "frame.h"
  22. #include "log.h"
  23. #include "pixfmt.h"
  24. enum AVHWDeviceType {
  25. AV_HWDEVICE_TYPE_VDPAU,
  26. AV_HWDEVICE_TYPE_CUDA,
  27. AV_HWDEVICE_TYPE_VAAPI,
  28. AV_HWDEVICE_TYPE_DXVA2,
  29. AV_HWDEVICE_TYPE_QSV,
  30. AV_HWDEVICE_TYPE_VIDEOTOOLBOX,
  31. AV_HWDEVICE_TYPE_NONE,
  32. AV_HWDEVICE_TYPE_D3D11VA,
  33. AV_HWDEVICE_TYPE_DRM,
  34. };
  35. typedef struct AVHWDeviceInternal AVHWDeviceInternal;
  36. /**
  37. * This struct aggregates all the (hardware/vendor-specific) "high-level" state,
  38. * i.e. state that is not tied to a concrete processing configuration.
  39. * E.g., in an API that supports hardware-accelerated encoding and decoding,
  40. * this struct will (if possible) wrap the state that is common to both encoding
  41. * and decoding and from which specific instances of encoders or decoders can be
  42. * derived.
  43. *
  44. * This struct is reference-counted with the AVBuffer mechanism. The
  45. * av_hwdevice_ctx_alloc() constructor yields a reference, whose data field
  46. * points to the actual AVHWDeviceContext. Further objects derived from
  47. * AVHWDeviceContext (such as AVHWFramesContext, describing a frame pool with
  48. * specific properties) will hold an internal reference to it. After all the
  49. * references are released, the AVHWDeviceContext itself will be freed,
  50. * optionally invoking a user-specified callback for uninitializing the hardware
  51. * state.
  52. */
  53. typedef struct AVHWDeviceContext {
  54. /**
  55. * A class for logging. Set by av_hwdevice_ctx_alloc().
  56. */
  57. const AVClass *av_class;
  58. /**
  59. * Private data used internally by libavutil. Must not be accessed in any
  60. * way by the caller.
  61. */
  62. AVHWDeviceInternal *internal;
  63. /**
  64. * This field identifies the underlying API used for hardware access.
  65. *
  66. * This field is set when this struct is allocated and never changed
  67. * afterwards.
  68. */
  69. enum AVHWDeviceType type;
  70. /**
  71. * The format-specific data, allocated and freed by libavutil along with
  72. * this context.
  73. *
  74. * Should be cast by the user to the format-specific context defined in the
  75. * corresponding header (hwcontext_*.h) and filled as described in the
  76. * documentation before calling av_hwdevice_ctx_init().
  77. *
  78. * After calling av_hwdevice_ctx_init() this struct should not be modified
  79. * by the caller.
  80. */
  81. void *hwctx;
  82. /**
  83. * This field may be set by the caller before calling av_hwdevice_ctx_init().
  84. *
  85. * If non-NULL, this callback will be called when the last reference to
  86. * this context is unreferenced, immediately before it is freed.
  87. *
  88. * @note when other objects (e.g an AVHWFramesContext) are derived from this
  89. * struct, this callback will be invoked after all such child objects
  90. * are fully uninitialized and their respective destructors invoked.
  91. */
  92. void (*free)(struct AVHWDeviceContext *ctx);
  93. /**
  94. * Arbitrary user data, to be used e.g. by the free() callback.
  95. */
  96. void *user_opaque;
  97. } AVHWDeviceContext;
  98. typedef struct AVHWFramesInternal AVHWFramesInternal;
  99. /**
  100. * This struct describes a set or pool of "hardware" frames (i.e. those with
  101. * data not located in normal system memory). All the frames in the pool are
  102. * assumed to be allocated in the same way and interchangeable.
  103. *
  104. * This struct is reference-counted with the AVBuffer mechanism and tied to a
  105. * given AVHWDeviceContext instance. The av_hwframe_ctx_alloc() constructor
  106. * yields a reference, whose data field points to the actual AVHWFramesContext
  107. * struct.
  108. */
  109. typedef struct AVHWFramesContext {
  110. /**
  111. * A class for logging.
  112. */
  113. const AVClass *av_class;
  114. /**
  115. * Private data used internally by libavutil. Must not be accessed in any
  116. * way by the caller.
  117. */
  118. AVHWFramesInternal *internal;
  119. /**
  120. * A reference to the parent AVHWDeviceContext. This reference is owned and
  121. * managed by the enclosing AVHWFramesContext, but the caller may derive
  122. * additional references from it.
  123. */
  124. AVBufferRef *device_ref;
  125. /**
  126. * The parent AVHWDeviceContext. This is simply a pointer to
  127. * device_ref->data provided for convenience.
  128. *
  129. * Set by libavutil in av_hwframe_ctx_init().
  130. */
  131. AVHWDeviceContext *device_ctx;
  132. /**
  133. * The format-specific data, allocated and freed automatically along with
  134. * this context.
  135. *
  136. * Should be cast by the user to the format-specific context defined in the
  137. * corresponding header (hwframe_*.h) and filled as described in the
  138. * documentation before calling av_hwframe_ctx_init().
  139. *
  140. * After any frames using this context are created, the contents of this
  141. * struct should not be modified by the caller.
  142. */
  143. void *hwctx;
  144. /**
  145. * This field may be set by the caller before calling av_hwframe_ctx_init().
  146. *
  147. * If non-NULL, this callback will be called when the last reference to
  148. * this context is unreferenced, immediately before it is freed.
  149. */
  150. void (*free)(struct AVHWFramesContext *ctx);
  151. /**
  152. * Arbitrary user data, to be used e.g. by the free() callback.
  153. */
  154. void *user_opaque;
  155. /**
  156. * A pool from which the frames are allocated by av_hwframe_get_buffer().
  157. * This field may be set by the caller before calling av_hwframe_ctx_init().
  158. * The buffers returned by calling av_buffer_pool_get() on this pool must
  159. * have the properties described in the documentation in the corresponding hw
  160. * type's header (hwcontext_*.h). The pool will be freed strictly before
  161. * this struct's free() callback is invoked.
  162. *
  163. * This field may be NULL, then libavutil will attempt to allocate a pool
  164. * internally. Note that certain device types enforce pools allocated at
  165. * fixed size (frame count), which cannot be extended dynamically. In such a
  166. * case, initial_pool_size must be set appropriately.
  167. */
  168. AVBufferPool *pool;
  169. /**
  170. * Initial size of the frame pool. If a device type does not support
  171. * dynamically resizing the pool, then this is also the maximum pool size.
  172. *
  173. * May be set by the caller before calling av_hwframe_ctx_init(). Must be
  174. * set if pool is NULL and the device type does not support dynamic pools.
  175. */
  176. int initial_pool_size;
  177. /**
  178. * The pixel format identifying the underlying HW surface type.
  179. *
  180. * Must be a hwaccel format, i.e. the corresponding descriptor must have the
  181. * AV_PIX_FMT_FLAG_HWACCEL flag set.
  182. *
  183. * Must be set by the user before calling av_hwframe_ctx_init().
  184. */
  185. enum AVPixelFormat format;
  186. /**
  187. * The pixel format identifying the actual data layout of the hardware
  188. * frames.
  189. *
  190. * Must be set by the caller before calling av_hwframe_ctx_init().
  191. *
  192. * @note when the underlying API does not provide the exact data layout, but
  193. * only the colorspace/bit depth, this field should be set to the fully
  194. * planar version of that format (e.g. for 8-bit 420 YUV it should be
  195. * AV_PIX_FMT_YUV420P, not AV_PIX_FMT_NV12 or anything else).
  196. */
  197. enum AVPixelFormat sw_format;
  198. /**
  199. * The allocated dimensions of the frames in this pool.
  200. *
  201. * Must be set by the user before calling av_hwframe_ctx_init().
  202. */
  203. int width, height;
  204. } AVHWFramesContext;
  205. /**
  206. * Look up an AVHWDeviceType by name.
  207. *
  208. * @param name String name of the device type (case-insensitive).
  209. * @return The type from enum AVHWDeviceType, or AV_HWDEVICE_TYPE_NONE if
  210. * not found.
  211. */
  212. enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name);
  213. /** Get the string name of an AVHWDeviceType.
  214. *
  215. * @param type Type from enum AVHWDeviceType.
  216. * @return Pointer to a static string containing the name, or NULL if the type
  217. * is not valid.
  218. */
  219. const char *av_hwdevice_get_type_name(enum AVHWDeviceType type);
  220. /**
  221. * Iterate over supported device types.
  222. *
  223. * @param type AV_HWDEVICE_TYPE_NONE initially, then the previous type
  224. * returned by this function in subsequent iterations.
  225. * @return The next usable device type from enum AVHWDeviceType, or
  226. * AV_HWDEVICE_TYPE_NONE if there are no more.
  227. */
  228. enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev);
  229. /**
  230. * Allocate an AVHWDeviceContext for a given hardware type.
  231. *
  232. * @param type the type of the hardware device to allocate.
  233. * @return a reference to the newly created AVHWDeviceContext on success or NULL
  234. * on failure.
  235. */
  236. AVBufferRef *av_hwdevice_ctx_alloc(enum AVHWDeviceType type);
  237. /**
  238. * Finalize the device context before use. This function must be called after
  239. * the context is filled with all the required information and before it is
  240. * used in any way.
  241. *
  242. * @param ref a reference to the AVHWDeviceContext
  243. * @return 0 on success, a negative AVERROR code on failure
  244. */
  245. int av_hwdevice_ctx_init(AVBufferRef *ref);
  246. /**
  247. * Open a device of the specified type and create an AVHWDeviceContext for it.
  248. *
  249. * This is a convenience function intended to cover the simple cases. Callers
  250. * who need to fine-tune device creation/management should open the device
  251. * manually and then wrap it in an AVHWDeviceContext using
  252. * av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
  253. *
  254. * The returned context is already initialized and ready for use, the caller
  255. * should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of
  256. * the created AVHWDeviceContext are set by this function and should not be
  257. * touched by the caller.
  258. *
  259. * @param device_ctx On success, a reference to the newly-created device context
  260. * will be written here. The reference is owned by the caller
  261. * and must be released with av_buffer_unref() when no longer
  262. * needed. On failure, NULL will be written to this pointer.
  263. * @param type The type of the device to create.
  264. * @param device A type-specific string identifying the device to open.
  265. * @param opts A dictionary of additional (type-specific) options to use in
  266. * opening the device. The dictionary remains owned by the caller.
  267. * @param flags currently unused
  268. *
  269. * @return 0 on success, a negative AVERROR code on failure.
  270. */
  271. int av_hwdevice_ctx_create(AVBufferRef **device_ctx, enum AVHWDeviceType type,
  272. const char *device, AVDictionary *opts, int flags);
  273. /**
  274. * Create a new device of the specified type from an existing device.
  275. *
  276. * If the source device is a device of the target type or was originally
  277. * derived from such a device (possibly through one or more intermediate
  278. * devices of other types), then this will return a reference to the
  279. * existing device of the same type as is requested.
  280. *
  281. * Otherwise, it will attempt to derive a new device from the given source
  282. * device. If direct derivation to the new type is not implemented, it will
  283. * attempt the same derivation from each ancestor of the source device in
  284. * turn looking for an implemented derivation method.
  285. *
  286. * @param dst_ctx On success, a reference to the newly-created
  287. * AVHWDeviceContext.
  288. * @param type The type of the new device to create.
  289. * @param src_ctx A reference to an existing AVHWDeviceContext which will be
  290. * used to create the new device.
  291. * @param flags Currently unused; should be set to zero.
  292. * @return Zero on success, a negative AVERROR code on failure.
  293. */
  294. int av_hwdevice_ctx_create_derived(AVBufferRef **dst_ctx,
  295. enum AVHWDeviceType type,
  296. AVBufferRef *src_ctx, int flags);
  297. /**
  298. * Allocate an AVHWFramesContext tied to a given device context.
  299. *
  300. * @param device_ctx a reference to a AVHWDeviceContext. This function will make
  301. * a new reference for internal use, the one passed to the
  302. * function remains owned by the caller.
  303. * @return a reference to the newly created AVHWFramesContext on success or NULL
  304. * on failure.
  305. */
  306. AVBufferRef *av_hwframe_ctx_alloc(AVBufferRef *device_ctx);
  307. /**
  308. * Finalize the context before use. This function must be called after the
  309. * context is filled with all the required information and before it is attached
  310. * to any frames.
  311. *
  312. * @param ref a reference to the AVHWFramesContext
  313. * @return 0 on success, a negative AVERROR code on failure
  314. */
  315. int av_hwframe_ctx_init(AVBufferRef *ref);
  316. /**
  317. * Allocate a new frame attached to the given AVHWFramesContext.
  318. *
  319. * @param hwframe_ctx a reference to an AVHWFramesContext
  320. * @param frame an empty (freshly allocated or unreffed) frame to be filled with
  321. * newly allocated buffers.
  322. * @param flags currently unused, should be set to zero
  323. * @return 0 on success, a negative AVERROR code on failure
  324. */
  325. int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags);
  326. /**
  327. * Copy data to or from a hw surface. At least one of dst/src must have an
  328. * AVHWFramesContext attached.
  329. *
  330. * If src has an AVHWFramesContext attached, then the format of dst (if set)
  331. * must use one of the formats returned by av_hwframe_transfer_get_formats(src,
  332. * AV_HWFRAME_TRANSFER_DIRECTION_FROM).
  333. * If dst has an AVHWFramesContext attached, then the format of src must use one
  334. * of the formats returned by av_hwframe_transfer_get_formats(dst,
  335. * AV_HWFRAME_TRANSFER_DIRECTION_TO)
  336. *
  337. * dst may be "clean" (i.e. with data/buf pointers unset), in which case the
  338. * data buffers will be allocated by this function using av_frame_get_buffer().
  339. * If dst->format is set, then this format will be used, otherwise (when
  340. * dst->format is AV_PIX_FMT_NONE) the first acceptable format will be chosen.
  341. *
  342. * The two frames must have matching allocated dimensions (i.e. equal to
  343. * AVHWFramesContext.width/height), since not all device types support
  344. * transferring a sub-rectangle of the whole surface. The display dimensions
  345. * (i.e. AVFrame.width/height) may be smaller than the allocated dimensions, but
  346. * also have to be equal for both frames. When the display dimensions are
  347. * smaller than the allocated dimensions, the content of the padding in the
  348. * destination frame is unspecified.
  349. *
  350. * @param dst the destination frame. dst is not touched on failure.
  351. * @param src the source frame.
  352. * @param flags currently unused, should be set to zero
  353. * @return 0 on success, a negative AVERROR error code on failure.
  354. */
  355. int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags);
  356. enum AVHWFrameTransferDirection {
  357. /**
  358. * Transfer the data from the queried hw frame.
  359. */
  360. AV_HWFRAME_TRANSFER_DIRECTION_FROM,
  361. /**
  362. * Transfer the data to the queried hw frame.
  363. */
  364. AV_HWFRAME_TRANSFER_DIRECTION_TO,
  365. };
  366. /**
  367. * Get a list of possible source or target formats usable in
  368. * av_hwframe_transfer_data().
  369. *
  370. * @param hwframe_ctx the frame context to obtain the information for
  371. * @param dir the direction of the transfer
  372. * @param formats the pointer to the output format list will be written here.
  373. * The list is terminated with AV_PIX_FMT_NONE and must be freed
  374. * by the caller when no longer needed using av_free().
  375. * If this function returns successfully, the format list will
  376. * have at least one item (not counting the terminator).
  377. * On failure, the contents of this pointer are unspecified.
  378. * @param flags currently unused, should be set to zero
  379. * @return 0 on success, a negative AVERROR code on failure.
  380. */
  381. int av_hwframe_transfer_get_formats(AVBufferRef *hwframe_ctx,
  382. enum AVHWFrameTransferDirection dir,
  383. enum AVPixelFormat **formats, int flags);
  384. /**
  385. * This struct describes the constraints on hardware frames attached to
  386. * a given device with a hardware-specific configuration. This is returned
  387. * by av_hwdevice_get_hwframe_constraints() and must be freed by
  388. * av_hwframe_constraints_free() after use.
  389. */
  390. typedef struct AVHWFramesConstraints {
  391. /**
  392. * A list of possible values for format in the hw_frames_ctx,
  393. * terminated by AV_PIX_FMT_NONE. This member will always be filled.
  394. */
  395. enum AVPixelFormat *valid_hw_formats;
  396. /**
  397. * A list of possible values for sw_format in the hw_frames_ctx,
  398. * terminated by AV_PIX_FMT_NONE. Can be NULL if this information is
  399. * not known.
  400. */
  401. enum AVPixelFormat *valid_sw_formats;
  402. /**
  403. * The minimum size of frames in this hw_frames_ctx.
  404. * (Zero if not known.)
  405. */
  406. int min_width;
  407. int min_height;
  408. /**
  409. * The maximum size of frames in this hw_frames_ctx.
  410. * (INT_MAX if not known / no limit.)
  411. */
  412. int max_width;
  413. int max_height;
  414. } AVHWFramesConstraints;
  415. /**
  416. * Allocate a HW-specific configuration structure for a given HW device.
  417. * After use, the user must free all members as required by the specific
  418. * hardware structure being used, then free the structure itself with
  419. * av_free().
  420. *
  421. * @param device_ctx a reference to the associated AVHWDeviceContext.
  422. * @return The newly created HW-specific configuration structure on
  423. * success or NULL on failure.
  424. */
  425. void *av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx);
  426. /**
  427. * Get the constraints on HW frames given a device and the HW-specific
  428. * configuration to be used with that device. If no HW-specific
  429. * configuration is provided, returns the maximum possible capabilities
  430. * of the device.
  431. *
  432. * @param ref a reference to the associated AVHWDeviceContext.
  433. * @param hwconfig a filled HW-specific configuration structure, or NULL
  434. * to return the maximum possible capabilities of the device.
  435. * @return AVHWFramesConstraints structure describing the constraints
  436. * on the device, or NULL if not available.
  437. */
  438. AVHWFramesConstraints *av_hwdevice_get_hwframe_constraints(AVBufferRef *ref,
  439. const void *hwconfig);
  440. /**
  441. * Free an AVHWFrameConstraints structure.
  442. *
  443. * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
  444. */
  445. void av_hwframe_constraints_free(AVHWFramesConstraints **constraints);
  446. /**
  447. * Flags to apply to frame mappings.
  448. */
  449. enum {
  450. /**
  451. * The mapping must be readable.
  452. */
  453. AV_HWFRAME_MAP_READ = 1 << 0,
  454. /**
  455. * The mapping must be writeable.
  456. */
  457. AV_HWFRAME_MAP_WRITE = 1 << 1,
  458. /**
  459. * The mapped frame will be overwritten completely in subsequent
  460. * operations, so the current frame data need not be loaded. Any values
  461. * which are not overwritten are unspecified.
  462. */
  463. AV_HWFRAME_MAP_OVERWRITE = 1 << 2,
  464. /**
  465. * The mapping must be direct. That is, there must not be any copying in
  466. * the map or unmap steps. Note that performance of direct mappings may
  467. * be much lower than normal memory.
  468. */
  469. AV_HWFRAME_MAP_DIRECT = 1 << 3,
  470. };
  471. /**
  472. * Map a hardware frame.
  473. *
  474. * This has a number of different possible effects, depending on the format
  475. * and origin of the src and dst frames. On input, src should be a usable
  476. * frame with valid buffers and dst should be blank (typically as just created
  477. * by av_frame_alloc()). src should have an associated hwframe context, and
  478. * dst may optionally have a format and associated hwframe context.
  479. *
  480. * If src was created by mapping a frame from the hwframe context of dst,
  481. * then this function undoes the mapping - dst is replaced by a reference to
  482. * the frame that src was originally mapped from.
  483. *
  484. * If both src and dst have an associated hwframe context, then this function
  485. * attempts to map the src frame from its hardware context to that of dst and
  486. * then fill dst with appropriate data to be usable there. This will only be
  487. * possible if the hwframe contexts and associated devices are compatible -
  488. * given compatible devices, av_hwframe_ctx_create_derived() can be used to
  489. * create a hwframe context for dst in which mapping should be possible.
  490. *
  491. * If src has a hwframe context but dst does not, then the src frame is
  492. * mapped to normal memory and should thereafter be usable as a normal frame.
  493. * If the format is set on dst, then the mapping will attempt to create dst
  494. * with that format and fail if it is not possible. If format is unset (is
  495. * AV_PIX_FMT_NONE) then dst will be mapped with whatever the most appropriate
  496. * format to use is (probably the sw_format of the src hwframe context).
  497. *
  498. * A return value of AVERROR(ENOSYS) indicates that the mapping is not
  499. * possible with the given arguments and hwframe setup, while other return
  500. * values indicate that it failed somehow.
  501. *
  502. * @param dst Destination frame, to contain the mapping.
  503. * @param src Source frame, to be mapped.
  504. * @param flags Some combination of AV_HWFRAME_MAP_* flags.
  505. * @return Zero on success, negative AVERROR code on failure.
  506. */
  507. int av_hwframe_map(AVFrame *dst, const AVFrame *src, int flags);
  508. /**
  509. * Create and initialise an AVHWFramesContext as a mapping of another existing
  510. * AVHWFramesContext on a different device.
  511. *
  512. * av_hwframe_ctx_init() should not be called after this.
  513. *
  514. * @param derived_frame_ctx On success, a reference to the newly created
  515. * AVHWFramesContext.
  516. * @param derived_device_ctx A reference to the device to create the new
  517. * AVHWFramesContext on.
  518. * @param source_frame_ctx A reference to an existing AVHWFramesContext
  519. * which will be mapped to the derived context.
  520. * @param flags Some combination of AV_HWFRAME_MAP_* flags, defining the
  521. * mapping parameters to apply to frames which are allocated
  522. * in the derived device.
  523. * @return Zero on success, negative AVERROR code on failure.
  524. */
  525. int av_hwframe_ctx_create_derived(AVBufferRef **derived_frame_ctx,
  526. enum AVPixelFormat format,
  527. AVBufferRef *derived_device_ctx,
  528. AVBufferRef *source_frame_ctx,
  529. int flags);
  530. #endif /* AVUTIL_HWCONTEXT_H */