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