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19 #ifndef AVUTIL_HWCONTEXT_H
20 #define AVUTIL_HWCONTEXT_H
28 AV_HWDEVICE_TYPE_NONE,
29 AV_HWDEVICE_TYPE_VDPAU,
30 AV_HWDEVICE_TYPE_CUDA,
31 AV_HWDEVICE_TYPE_VAAPI,
32 AV_HWDEVICE_TYPE_DXVA2,
34 AV_HWDEVICE_TYPE_D3D11VA,
37 typedef struct AVHWDeviceInternal AVHWDeviceInternal;
40 * This struct aggregates all the (hardware/vendor-specific) "high-level" state,
41 * i.e. state that is not tied to a concrete processing configuration.
42 * E.g., in an API that supports hardware-accelerated encoding and decoding,
43 * this struct will (if possible) wrap the state that is common to both encoding
44 * and decoding and from which specific instances of encoders or decoders can be
47 * This struct is reference-counted with the AVBuffer mechanism. The
48 * av_hwdevice_ctx_alloc() constructor yields a reference, whose data field
49 * points to the actual AVHWDeviceContext. Further objects derived from
50 * AVHWDeviceContext (such as AVHWFramesContext, describing a frame pool with
51 * specific properties) will hold an internal reference to it. After all the
52 * references are released, the AVHWDeviceContext itself will be freed,
53 * optionally invoking a user-specified callback for uninitializing the hardware
56 typedef struct AVHWDeviceContext {
58 * A class for logging. Set by av_hwdevice_ctx_alloc().
60 const AVClass *av_class;
63 * Private data used internally by libavutil. Must not be accessed in any
66 AVHWDeviceInternal *internal;
69 * This field identifies the underlying API used for hardware access.
71 * This field is set when this struct is allocated and never changed
74 enum AVHWDeviceType type;
77 * The format-specific data, allocated and freed by libavutil along with
80 * Should be cast by the user to the format-specific context defined in the
81 * corresponding header (hwcontext_*.h) and filled as described in the
82 * documentation before calling av_hwdevice_ctx_init().
84 * After calling av_hwdevice_ctx_init() this struct should not be modified
90 * This field may be set by the caller before calling av_hwdevice_ctx_init().
92 * If non-NULL, this callback will be called when the last reference to
93 * this context is unreferenced, immediately before it is freed.
95 * @note when other objects (e.g an AVHWFramesContext) are derived from this
96 * struct, this callback will be invoked after all such child objects
97 * are fully uninitialized and their respective destructors invoked.
99 void (*free)(struct AVHWDeviceContext *ctx);
102 * Arbitrary user data, to be used e.g. by the free() callback.
107 typedef struct AVHWFramesInternal AVHWFramesInternal;
110 * This struct describes a set or pool of "hardware" frames (i.e. those with
111 * data not located in normal system memory). All the frames in the pool are
112 * assumed to be allocated in the same way and interchangeable.
114 * This struct is reference-counted with the AVBuffer mechanism and tied to a
115 * given AVHWDeviceContext instance. The av_hwframe_ctx_alloc() constructor
116 * yields a reference, whose data field points to the actual AVHWFramesContext
119 typedef struct AVHWFramesContext {
121 * A class for logging.
123 const AVClass *av_class;
126 * Private data used internally by libavutil. Must not be accessed in any
129 AVHWFramesInternal *internal;
132 * A reference to the parent AVHWDeviceContext. This reference is owned and
133 * managed by the enclosing AVHWFramesContext, but the caller may derive
134 * additional references from it.
136 AVBufferRef *device_ref;
139 * The parent AVHWDeviceContext. This is simply a pointer to
140 * device_ref->data provided for convenience.
142 * Set by libavutil in av_hwframe_ctx_init().
144 AVHWDeviceContext *device_ctx;
147 * The format-specific data, allocated and freed automatically along with
150 * Should be cast by the user to the format-specific context defined in the
151 * corresponding header (hwframe_*.h) and filled as described in the
152 * documentation before calling av_hwframe_ctx_init().
154 * After any frames using this context are created, the contents of this
155 * struct should not be modified by the caller.
160 * This field may be set by the caller before calling av_hwframe_ctx_init().
162 * If non-NULL, this callback will be called when the last reference to
163 * this context is unreferenced, immediately before it is freed.
165 void (*free)(struct AVHWFramesContext *ctx);
168 * Arbitrary user data, to be used e.g. by the free() callback.
173 * A pool from which the frames are allocated by av_hwframe_get_buffer().
174 * This field may be set by the caller before calling av_hwframe_ctx_init().
175 * The buffers returned by calling av_buffer_pool_get() on this pool must
176 * have the properties described in the documentation in the corresponding hw
177 * type's header (hwcontext_*.h). The pool will be freed strictly before
178 * this struct's free() callback is invoked.
180 * This field may be NULL, then libavutil will attempt to allocate a pool
181 * internally. Note that certain device types enforce pools allocated at
182 * fixed size (frame count), which cannot be extended dynamically. In such a
183 * case, initial_pool_size must be set appropriately.
188 * Initial size of the frame pool. If a device type does not support
189 * dynamically resizing the pool, then this is also the maximum pool size.
191 * May be set by the caller before calling av_hwframe_ctx_init(). Must be
192 * set if pool is NULL and the device type does not support dynamic pools.
194 int initial_pool_size;
197 * The pixel format identifying the underlying HW surface type.
199 * Must be a hwaccel format, i.e. the corresponding descriptor must have the
200 * AV_PIX_FMT_FLAG_HWACCEL flag set.
202 * Must be set by the user before calling av_hwframe_ctx_init().
204 enum AVPixelFormat format;
207 * The pixel format identifying the actual data layout of the hardware
210 * Must be set by the caller before calling av_hwframe_ctx_init().
212 * @note when the underlying API does not provide the exact data layout, but
213 * only the colorspace/bit depth, this field should be set to the fully
214 * planar version of that format (e.g. for 8-bit 420 YUV it should be
215 * AV_PIX_FMT_YUV420P, not AV_PIX_FMT_NV12 or anything else).
217 enum AVPixelFormat sw_format;
220 * The allocated dimensions of the frames in this pool.
222 * Must be set by the user before calling av_hwframe_ctx_init().
228 * Look up an AVHWDeviceType by name.
230 * @param name String name of the device type (case-insensitive).
231 * @return The type from enum AVHWDeviceType, or AV_HWDEVICE_TYPE_NONE if
234 enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name);
236 /** Get the string name of an AVHWDeviceType.
238 * @param type Type from enum AVHWDeviceType.
239 * @return Pointer to a static string containing the name, or NULL if the type
242 const char *av_hwdevice_get_type_name(enum AVHWDeviceType type);
245 * Iterate over supported device types.
247 * @param type AV_HWDEVICE_TYPE_NONE initially, then the previous type
248 * returned by this function in subsequent iterations.
249 * @return The next usable device type from enum AVHWDeviceType, or
250 * AV_HWDEVICE_TYPE_NONE if there are no more.
252 enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev);
255 * Allocate an AVHWDeviceContext for a given hardware type.
257 * @param type the type of the hardware device to allocate.
258 * @return a reference to the newly created AVHWDeviceContext on success or NULL
261 AVBufferRef *av_hwdevice_ctx_alloc(enum AVHWDeviceType type);
264 * Finalize the device context before use. This function must be called after
265 * the context is filled with all the required information and before it is
268 * @param ref a reference to the AVHWDeviceContext
269 * @return 0 on success, a negative AVERROR code on failure
271 int av_hwdevice_ctx_init(AVBufferRef *ref);
274 * Open a device of the specified type and create an AVHWDeviceContext for it.
276 * This is a convenience function intended to cover the simple cases. Callers
277 * who need to fine-tune device creation/management should open the device
278 * manually and then wrap it in an AVHWDeviceContext using
279 * av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
281 * The returned context is already initialized and ready for use, the caller
282 * should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of
283 * the created AVHWDeviceContext are set by this function and should not be
284 * touched by the caller.
286 * @param device_ctx On success, a reference to the newly-created device context
287 * will be written here. The reference is owned by the caller
288 * and must be released with av_buffer_unref() when no longer
289 * needed. On failure, NULL will be written to this pointer.
290 * @param type The type of the device to create.
291 * @param device A type-specific string identifying the device to open.
292 * @param opts A dictionary of additional (type-specific) options to use in
293 * opening the device. The dictionary remains owned by the caller.
294 * @param flags currently unused
296 * @return 0 on success, a negative AVERROR code on failure.
298 int av_hwdevice_ctx_create(AVBufferRef **device_ctx, enum AVHWDeviceType type,
299 const char *device, AVDictionary *opts, int flags);
302 * Create a new device of the specified type from an existing device.
304 * If the source device is a device of the target type or was originally
305 * derived from such a device (possibly through one or more intermediate
306 * devices of other types), then this will return a reference to the
307 * existing device of the same type as is requested.
309 * Otherwise, it will attempt to derive a new device from the given source
310 * device. If direct derivation to the new type is not implemented, it will
311 * attempt the same derivation from each ancestor of the source device in
312 * turn looking for an implemented derivation method.
314 * @param dst_ctx On success, a reference to the newly-created
316 * @param type The type of the new device to create.
317 * @param src_ctx A reference to an existing AVHWDeviceContext which will be
318 * used to create the new device.
319 * @param flags Currently unused; should be set to zero.
320 * @return Zero on success, a negative AVERROR code on failure.
322 int av_hwdevice_ctx_create_derived(AVBufferRef **dst_ctx,
323 enum AVHWDeviceType type,
324 AVBufferRef *src_ctx, int flags);
328 * Allocate an AVHWFramesContext tied to a given device context.
330 * @param device_ctx a reference to a AVHWDeviceContext. This function will make
331 * a new reference for internal use, the one passed to the
332 * function remains owned by the caller.
333 * @return a reference to the newly created AVHWFramesContext on success or NULL
336 AVBufferRef *av_hwframe_ctx_alloc(AVBufferRef *device_ctx);
339 * Finalize the context before use. This function must be called after the
340 * context is filled with all the required information and before it is attached
343 * @param ref a reference to the AVHWFramesContext
344 * @return 0 on success, a negative AVERROR code on failure
346 int av_hwframe_ctx_init(AVBufferRef *ref);
349 * Allocate a new frame attached to the given AVHWFramesContext.
351 * @param hwframe_ctx a reference to an AVHWFramesContext
352 * @param frame an empty (freshly allocated or unreffed) frame to be filled with
353 * newly allocated buffers.
354 * @param flags currently unused, should be set to zero
355 * @return 0 on success, a negative AVERROR code on failure
357 int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags);
360 * Copy data to or from a hw surface. At least one of dst/src must have an
361 * AVHWFramesContext attached.
363 * If src has an AVHWFramesContext attached, then the format of dst (if set)
364 * must use one of the formats returned by av_hwframe_transfer_get_formats(src,
365 * AV_HWFRAME_TRANSFER_DIRECTION_FROM).
366 * If dst has an AVHWFramesContext attached, then the format of src must use one
367 * of the formats returned by av_hwframe_transfer_get_formats(dst,
368 * AV_HWFRAME_TRANSFER_DIRECTION_TO)
370 * dst may be "clean" (i.e. with data/buf pointers unset), in which case the
371 * data buffers will be allocated by this function using av_frame_get_buffer().
372 * If dst->format is set, then this format will be used, otherwise (when
373 * dst->format is AV_PIX_FMT_NONE) the first acceptable format will be chosen.
375 * The two frames must have matching allocated dimensions (i.e. equal to
376 * AVHWFramesContext.width/height), since not all device types support
377 * transferring a sub-rectangle of the whole surface. The display dimensions
378 * (i.e. AVFrame.width/height) may be smaller than the allocated dimensions, but
379 * also have to be equal for both frames. When the display dimensions are
380 * smaller than the allocated dimensions, the content of the padding in the
381 * destination frame is unspecified.
383 * @param dst the destination frame. dst is not touched on failure.
384 * @param src the source frame.
385 * @param flags currently unused, should be set to zero
386 * @return 0 on success, a negative AVERROR error code on failure.
388 int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags);
390 enum AVHWFrameTransferDirection {
392 * Transfer the data from the queried hw frame.
394 AV_HWFRAME_TRANSFER_DIRECTION_FROM,
397 * Transfer the data to the queried hw frame.
399 AV_HWFRAME_TRANSFER_DIRECTION_TO,
403 * Get a list of possible source or target formats usable in
404 * av_hwframe_transfer_data().
406 * @param hwframe_ctx the frame context to obtain the information for
407 * @param dir the direction of the transfer
408 * @param formats the pointer to the output format list will be written here.
409 * The list is terminated with AV_PIX_FMT_NONE and must be freed
410 * by the caller when no longer needed using av_free().
411 * If this function returns successfully, the format list will
412 * have at least one item (not counting the terminator).
413 * On failure, the contents of this pointer are unspecified.
414 * @param flags currently unused, should be set to zero
415 * @return 0 on success, a negative AVERROR code on failure.
417 int av_hwframe_transfer_get_formats(AVBufferRef *hwframe_ctx,
418 enum AVHWFrameTransferDirection dir,
419 enum AVPixelFormat **formats, int flags);
423 * This struct describes the constraints on hardware frames attached to
424 * a given device with a hardware-specific configuration. This is returned
425 * by av_hwdevice_get_hwframe_constraints() and must be freed by
426 * av_hwframe_constraints_free() after use.
428 typedef struct AVHWFramesConstraints {
430 * A list of possible values for format in the hw_frames_ctx,
431 * terminated by AV_PIX_FMT_NONE. This member will always be filled.
433 enum AVPixelFormat *valid_hw_formats;
436 * A list of possible values for sw_format in the hw_frames_ctx,
437 * terminated by AV_PIX_FMT_NONE. Can be NULL if this information is
440 enum AVPixelFormat *valid_sw_formats;
443 * The minimum size of frames in this hw_frames_ctx.
444 * (Zero if not known.)
450 * The maximum size of frames in this hw_frames_ctx.
451 * (INT_MAX if not known / no limit.)
455 } AVHWFramesConstraints;
458 * Allocate a HW-specific configuration structure for a given HW device.
459 * After use, the user must free all members as required by the specific
460 * hardware structure being used, then free the structure itself with
463 * @param device_ctx a reference to the associated AVHWDeviceContext.
464 * @return The newly created HW-specific configuration structure on
465 * success or NULL on failure.
467 void *av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx);
470 * Get the constraints on HW frames given a device and the HW-specific
471 * configuration to be used with that device. If no HW-specific
472 * configuration is provided, returns the maximum possible capabilities
475 * @param ref a reference to the associated AVHWDeviceContext.
476 * @param hwconfig a filled HW-specific configuration structure, or NULL
477 * to return the maximum possible capabilities of the device.
478 * @return AVHWFramesConstraints structure describing the constraints
479 * on the device, or NULL if not available.
481 AVHWFramesConstraints *av_hwdevice_get_hwframe_constraints(AVBufferRef *ref,
482 const void *hwconfig);
485 * Free an AVHWFrameConstraints structure.
487 * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
489 void av_hwframe_constraints_free(AVHWFramesConstraints **constraints);
493 * Flags to apply to frame mappings.
497 * The mapping must be readable.
499 AV_HWFRAME_MAP_READ = 1 << 0,
501 * The mapping must be writeable.
503 AV_HWFRAME_MAP_WRITE = 1 << 1,
505 * The mapped frame will be overwritten completely in subsequent
506 * operations, so the current frame data need not be loaded. Any values
507 * which are not overwritten are unspecified.
509 AV_HWFRAME_MAP_OVERWRITE = 1 << 2,
511 * The mapping must be direct. That is, there must not be any copying in
512 * the map or unmap steps. Note that performance of direct mappings may
513 * be much lower than normal memory.
515 AV_HWFRAME_MAP_DIRECT = 1 << 3,
519 * Map a hardware frame.
521 * This has a number of different possible effects, depending on the format
522 * and origin of the src and dst frames. On input, src should be a usable
523 * frame with valid buffers and dst should be blank (typically as just created
524 * by av_frame_alloc()). src should have an associated hwframe context, and
525 * dst may optionally have a format and associated hwframe context.
527 * If src was created by mapping a frame from the hwframe context of dst,
528 * then this function undoes the mapping - dst is replaced by a reference to
529 * the frame that src was originally mapped from.
531 * If both src and dst have an associated hwframe context, then this function
532 * attempts to map the src frame from its hardware context to that of dst and
533 * then fill dst with appropriate data to be usable there. This will only be
534 * possible if the hwframe contexts and associated devices are compatible -
535 * given compatible devices, av_hwframe_ctx_create_derived() can be used to
536 * create a hwframe context for dst in which mapping should be possible.
538 * If src has a hwframe context but dst does not, then the src frame is
539 * mapped to normal memory and should thereafter be usable as a normal frame.
540 * If the format is set on dst, then the mapping will attempt to create dst
541 * with that format and fail if it is not possible. If format is unset (is
542 * AV_PIX_FMT_NONE) then dst will be mapped with whatever the most appropriate
543 * format to use is (probably the sw_format of the src hwframe context).
545 * A return value of AVERROR(ENOSYS) indicates that the mapping is not
546 * possible with the given arguments and hwframe setup, while other return
547 * values indicate that it failed somehow.
549 * @param dst Destination frame, to contain the mapping.
550 * @param src Source frame, to be mapped.
551 * @param flags Some combination of AV_HWFRAME_MAP_* flags.
552 * @return Zero on success, negative AVERROR code on failure.
554 int av_hwframe_map(AVFrame *dst, const AVFrame *src, int flags);
558 * Create and initialise an AVHWFramesContext as a mapping of another existing
559 * AVHWFramesContext on a different device.
561 * av_hwframe_ctx_init() should not be called after this.
563 * @param derived_frame_ctx On success, a reference to the newly created
565 * @param derived_device_ctx A reference to the device to create the new
566 * AVHWFramesContext on.
567 * @param source_frame_ctx A reference to an existing AVHWFramesContext
568 * which will be mapped to the derived context.
569 * @param flags Some combination of AV_HWFRAME_MAP_* flags, defining the
570 * mapping parameters to apply to frames which are allocated
571 * in the derived device.
572 * @return Zero on success, negative AVERROR code on failure.
574 int av_hwframe_ctx_create_derived(AVBufferRef **derived_frame_ctx,
575 enum AVPixelFormat format,
576 AVBufferRef *derived_device_ctx,
577 AVBufferRef *source_frame_ctx,
580 #endif /* AVUTIL_HWCONTEXT_H */