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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_NONE,
29     AV_HWDEVICE_TYPE_VDPAU,
30     AV_HWDEVICE_TYPE_CUDA,
31     AV_HWDEVICE_TYPE_VAAPI,
32     AV_HWDEVICE_TYPE_DXVA2,
33     AV_HWDEVICE_TYPE_QSV,
34     AV_HWDEVICE_TYPE_VIDEOTOOLBOX,
35     AV_HWDEVICE_TYPE_D3D11VA,
36     AV_HWDEVICE_TYPE_DRM,
37     AV_HWDEVICE_TYPE_OPENCL,
38     AV_HWDEVICE_TYPE_MEDIACODEC,
39     AV_HWDEVICE_TYPE_VULKAN,
40 };
41 
42 typedef struct AVHWDeviceInternal AVHWDeviceInternal;
43 
44 /**
45  * This struct aggregates all the (hardware/vendor-specific) "high-level" state,
46  * i.e. state that is not tied to a concrete processing configuration.
47  * E.g., in an API that supports hardware-accelerated encoding and decoding,
48  * this struct will (if possible) wrap the state that is common to both encoding
49  * and decoding and from which specific instances of encoders or decoders can be
50  * derived.
51  *
52  * This struct is reference-counted with the AVBuffer mechanism. The
53  * av_hwdevice_ctx_alloc() constructor yields a reference, whose data field
54  * points to the actual AVHWDeviceContext. Further objects derived from
55  * AVHWDeviceContext (such as AVHWFramesContext, describing a frame pool with
56  * specific properties) will hold an internal reference to it. After all the
57  * references are released, the AVHWDeviceContext itself will be freed,
58  * optionally invoking a user-specified callback for uninitializing the hardware
59  * state.
60  */
61 typedef struct AVHWDeviceContext {
62     /**
63      * A class for logging. Set by av_hwdevice_ctx_alloc().
64      */
65     const AVClass *av_class;
66 
67     /**
68      * Private data used internally by libavutil. Must not be accessed in any
69      * way by the caller.
70      */
71     AVHWDeviceInternal *internal;
72 
73     /**
74      * This field identifies the underlying API used for hardware access.
75      *
76      * This field is set when this struct is allocated and never changed
77      * afterwards.
78      */
79     enum AVHWDeviceType type;
80 
81     /**
82      * The format-specific data, allocated and freed by libavutil along with
83      * this context.
84      *
85      * Should be cast by the user to the format-specific context defined in the
86      * corresponding header (hwcontext_*.h) and filled as described in the
87      * documentation before calling av_hwdevice_ctx_init().
88      *
89      * After calling av_hwdevice_ctx_init() this struct should not be modified
90      * by the caller.
91      */
92     void *hwctx;
93 
94     /**
95      * This field may be set by the caller before calling av_hwdevice_ctx_init().
96      *
97      * If non-NULL, this callback will be called when the last reference to
98      * this context is unreferenced, immediately before it is freed.
99      *
100      * @note when other objects (e.g an AVHWFramesContext) are derived from this
101      *       struct, this callback will be invoked after all such child objects
102      *       are fully uninitialized and their respective destructors invoked.
103      */
104     void (*free)(struct AVHWDeviceContext *ctx);
105 
106     /**
107      * Arbitrary user data, to be used e.g. by the free() callback.
108      */
109     void *user_opaque;
110 } AVHWDeviceContext;
111 
112 typedef struct AVHWFramesInternal AVHWFramesInternal;
113 
114 /**
115  * This struct describes a set or pool of "hardware" frames (i.e. those with
116  * data not located in normal system memory). All the frames in the pool are
117  * assumed to be allocated in the same way and interchangeable.
118  *
119  * This struct is reference-counted with the AVBuffer mechanism and tied to a
120  * given AVHWDeviceContext instance. The av_hwframe_ctx_alloc() constructor
121  * yields a reference, whose data field points to the actual AVHWFramesContext
122  * struct.
123  */
124 typedef struct AVHWFramesContext {
125     /**
126      * A class for logging.
127      */
128     const AVClass *av_class;
129 
130     /**
131      * Private data used internally by libavutil. Must not be accessed in any
132      * way by the caller.
133      */
134     AVHWFramesInternal *internal;
135 
136     /**
137      * A reference to the parent AVHWDeviceContext. This reference is owned and
138      * managed by the enclosing AVHWFramesContext, but the caller may derive
139      * additional references from it.
140      */
141     AVBufferRef *device_ref;
142 
143     /**
144      * The parent AVHWDeviceContext. This is simply a pointer to
145      * device_ref->data provided for convenience.
146      *
147      * Set by libavutil in av_hwframe_ctx_init().
148      */
149     AVHWDeviceContext *device_ctx;
150 
151     /**
152      * The format-specific data, allocated and freed automatically along with
153      * this context.
154      *
155      * Should be cast by the user to the format-specific context defined in the
156      * corresponding header (hwframe_*.h) and filled as described in the
157      * documentation before calling av_hwframe_ctx_init().
158      *
159      * After any frames using this context are created, the contents of this
160      * struct should not be modified by the caller.
161      */
162     void *hwctx;
163 
164     /**
165      * This field may be set by the caller before calling av_hwframe_ctx_init().
166      *
167      * If non-NULL, this callback will be called when the last reference to
168      * this context is unreferenced, immediately before it is freed.
169      */
170     void (*free)(struct AVHWFramesContext *ctx);
171 
172     /**
173      * Arbitrary user data, to be used e.g. by the free() callback.
174      */
175     void *user_opaque;
176 
177     /**
178      * A pool from which the frames are allocated by av_hwframe_get_buffer().
179      * This field may be set by the caller before calling av_hwframe_ctx_init().
180      * The buffers returned by calling av_buffer_pool_get() on this pool must
181      * have the properties described in the documentation in the corresponding hw
182      * type's header (hwcontext_*.h). The pool will be freed strictly before
183      * this struct's free() callback is invoked.
184      *
185      * This field may be NULL, then libavutil will attempt to allocate a pool
186      * internally. Note that certain device types enforce pools allocated at
187      * fixed size (frame count), which cannot be extended dynamically. In such a
188      * case, initial_pool_size must be set appropriately.
189      */
190     AVBufferPool *pool;
191 
192     /**
193      * Initial size of the frame pool. If a device type does not support
194      * dynamically resizing the pool, then this is also the maximum pool size.
195      *
196      * May be set by the caller before calling av_hwframe_ctx_init(). Must be
197      * set if pool is NULL and the device type does not support dynamic pools.
198      */
199     int initial_pool_size;
200 
201     /**
202      * The pixel format identifying the underlying HW surface type.
203      *
204      * Must be a hwaccel format, i.e. the corresponding descriptor must have the
205      * AV_PIX_FMT_FLAG_HWACCEL flag set.
206      *
207      * Must be set by the user before calling av_hwframe_ctx_init().
208      */
209     enum AVPixelFormat format;
210 
211     /**
212      * The pixel format identifying the actual data layout of the hardware
213      * frames.
214      *
215      * Must be set by the caller before calling av_hwframe_ctx_init().
216      *
217      * @note when the underlying API does not provide the exact data layout, but
218      * only the colorspace/bit depth, this field should be set to the fully
219      * planar version of that format (e.g. for 8-bit 420 YUV it should be
220      * AV_PIX_FMT_YUV420P, not AV_PIX_FMT_NV12 or anything else).
221      */
222     enum AVPixelFormat sw_format;
223 
224     /**
225      * The allocated dimensions of the frames in this pool.
226      *
227      * Must be set by the user before calling av_hwframe_ctx_init().
228      */
229     int width, height;
230 } AVHWFramesContext;
231 
232 /**
233  * Look up an AVHWDeviceType by name.
234  *
235  * @param name String name of the device type (case-insensitive).
236  * @return The type from enum AVHWDeviceType, or AV_HWDEVICE_TYPE_NONE if
237  *         not found.
238  */
239 enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name);
240 
241 /** Get the string name of an AVHWDeviceType.
242  *
243  * @param type Type from enum AVHWDeviceType.
244  * @return Pointer to a static string containing the name, or NULL if the type
245  *         is not valid.
246  */
247 const char *av_hwdevice_get_type_name(enum AVHWDeviceType type);
248 
249 /**
250  * Iterate over supported device types.
251  *
252  * @param type AV_HWDEVICE_TYPE_NONE initially, then the previous type
253  *             returned by this function in subsequent iterations.
254  * @return The next usable device type from enum AVHWDeviceType, or
255  *         AV_HWDEVICE_TYPE_NONE if there are no more.
256  */
257 enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev);
258 
259 /**
260  * Allocate an AVHWDeviceContext for a given hardware type.
261  *
262  * @param type the type of the hardware device to allocate.
263  * @return a reference to the newly created AVHWDeviceContext on success or NULL
264  *         on failure.
265  */
266 AVBufferRef *av_hwdevice_ctx_alloc(enum AVHWDeviceType type);
267 
268 /**
269  * Finalize the device context before use. This function must be called after
270  * the context is filled with all the required information and before it is
271  * used in any way.
272  *
273  * @param ref a reference to the AVHWDeviceContext
274  * @return 0 on success, a negative AVERROR code on failure
275  */
276 int av_hwdevice_ctx_init(AVBufferRef *ref);
277 
278 /**
279  * Open a device of the specified type and create an AVHWDeviceContext for it.
280  *
281  * This is a convenience function intended to cover the simple cases. Callers
282  * who need to fine-tune device creation/management should open the device
283  * manually and then wrap it in an AVHWDeviceContext using
284  * av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
285  *
286  * The returned context is already initialized and ready for use, the caller
287  * should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of
288  * the created AVHWDeviceContext are set by this function and should not be
289  * touched by the caller.
290  *
291  * @param device_ctx On success, a reference to the newly-created device context
292  *                   will be written here. The reference is owned by the caller
293  *                   and must be released with av_buffer_unref() when no longer
294  *                   needed. On failure, NULL will be written to this pointer.
295  * @param type The type of the device to create.
296  * @param device A type-specific string identifying the device to open.
297  * @param opts A dictionary of additional (type-specific) options to use in
298  *             opening the device. The dictionary remains owned by the caller.
299  * @param flags currently unused
300  *
301  * @return 0 on success, a negative AVERROR code on failure.
302  */
303 int av_hwdevice_ctx_create(AVBufferRef **device_ctx, enum AVHWDeviceType type,
304                            const char *device, AVDictionary *opts, int flags);
305 
306 /**
307  * Create a new device of the specified type from an existing device.
308  *
309  * If the source device is a device of the target type or was originally
310  * derived from such a device (possibly through one or more intermediate
311  * devices of other types), then this will return a reference to the
312  * existing device of the same type as is requested.
313  *
314  * Otherwise, it will attempt to derive a new device from the given source
315  * device.  If direct derivation to the new type is not implemented, it will
316  * attempt the same derivation from each ancestor of the source device in
317  * turn looking for an implemented derivation method.
318  *
319  * @param dst_ctx On success, a reference to the newly-created
320  *                AVHWDeviceContext.
321  * @param type    The type of the new device to create.
322  * @param src_ctx A reference to an existing AVHWDeviceContext which will be
323  *                used to create the new device.
324  * @param flags   Currently unused; should be set to zero.
325  * @return        Zero on success, a negative AVERROR code on failure.
326  */
327 int av_hwdevice_ctx_create_derived(AVBufferRef **dst_ctx,
328                                    enum AVHWDeviceType type,
329                                    AVBufferRef *src_ctx, int flags);
330 
331 /**
332  * Create a new device of the specified type from an existing device.
333  *
334  * This function performs the same action as av_hwdevice_ctx_create_derived,
335  * however, it is able to set options for the new device to be derived.
336  *
337  * @param dst_ctx On success, a reference to the newly-created
338  *                AVHWDeviceContext.
339  * @param type    The type of the new device to create.
340  * @param src_ctx A reference to an existing AVHWDeviceContext which will be
341  *                used to create the new device.
342  * @param options Options for the new device to create, same format as in
343  *                av_hwdevice_ctx_create.
344  * @param flags   Currently unused; should be set to zero.
345  * @return        Zero on success, a negative AVERROR code on failure.
346  */
347 int av_hwdevice_ctx_create_derived_opts(AVBufferRef **dst_ctx,
348                                         enum AVHWDeviceType type,
349                                         AVBufferRef *src_ctx,
350                                         AVDictionary *options, int flags);
351 
352 /**
353  * Allocate an AVHWFramesContext tied to a given device context.
354  *
355  * @param device_ctx a reference to a AVHWDeviceContext. This function will make
356  *                   a new reference for internal use, the one passed to the
357  *                   function remains owned by the caller.
358  * @return a reference to the newly created AVHWFramesContext on success or NULL
359  *         on failure.
360  */
361 AVBufferRef *av_hwframe_ctx_alloc(AVBufferRef *device_ctx);
362 
363 /**
364  * Finalize the context before use. This function must be called after the
365  * context is filled with all the required information and before it is attached
366  * to any frames.
367  *
368  * @param ref a reference to the AVHWFramesContext
369  * @return 0 on success, a negative AVERROR code on failure
370  */
371 int av_hwframe_ctx_init(AVBufferRef *ref);
372 
373 /**
374  * Allocate a new frame attached to the given AVHWFramesContext.
375  *
376  * @param hwframe_ctx a reference to an AVHWFramesContext
377  * @param frame an empty (freshly allocated or unreffed) frame to be filled with
378  *              newly allocated buffers.
379  * @param flags currently unused, should be set to zero
380  * @return 0 on success, a negative AVERROR code on failure
381  */
382 int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags);
383 
384 /**
385  * Copy data to or from a hw surface. At least one of dst/src must have an
386  * AVHWFramesContext attached.
387  *
388  * If src has an AVHWFramesContext attached, then the format of dst (if set)
389  * must use one of the formats returned by av_hwframe_transfer_get_formats(src,
390  * AV_HWFRAME_TRANSFER_DIRECTION_FROM).
391  * If dst has an AVHWFramesContext attached, then the format of src must use one
392  * of the formats returned by av_hwframe_transfer_get_formats(dst,
393  * AV_HWFRAME_TRANSFER_DIRECTION_TO)
394  *
395  * dst may be "clean" (i.e. with data/buf pointers unset), in which case the
396  * data buffers will be allocated by this function using av_frame_get_buffer().
397  * If dst->format is set, then this format will be used, otherwise (when
398  * dst->format is AV_PIX_FMT_NONE) the first acceptable format will be chosen.
399  *
400  * The two frames must have matching allocated dimensions (i.e. equal to
401  * AVHWFramesContext.width/height), since not all device types support
402  * transferring a sub-rectangle of the whole surface. The display dimensions
403  * (i.e. AVFrame.width/height) may be smaller than the allocated dimensions, but
404  * also have to be equal for both frames. When the display dimensions are
405  * smaller than the allocated dimensions, the content of the padding in the
406  * destination frame is unspecified.
407  *
408  * @param dst the destination frame. dst is not touched on failure.
409  * @param src the source frame.
410  * @param flags currently unused, should be set to zero
411  * @return 0 on success, a negative AVERROR error code on failure.
412  */
413 int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags);
414 
415 enum AVHWFrameTransferDirection {
416     /**
417      * Transfer the data from the queried hw frame.
418      */
419     AV_HWFRAME_TRANSFER_DIRECTION_FROM,
420 
421     /**
422      * Transfer the data to the queried hw frame.
423      */
424     AV_HWFRAME_TRANSFER_DIRECTION_TO,
425 };
426 
427 /**
428  * Get a list of possible source or target formats usable in
429  * av_hwframe_transfer_data().
430  *
431  * @param hwframe_ctx the frame context to obtain the information for
432  * @param dir the direction of the transfer
433  * @param formats the pointer to the output format list will be written here.
434  *                The list is terminated with AV_PIX_FMT_NONE and must be freed
435  *                by the caller when no longer needed using av_free().
436  *                If this function returns successfully, the format list will
437  *                have at least one item (not counting the terminator).
438  *                On failure, the contents of this pointer are unspecified.
439  * @param flags currently unused, should be set to zero
440  * @return 0 on success, a negative AVERROR code on failure.
441  */
442 int av_hwframe_transfer_get_formats(AVBufferRef *hwframe_ctx,
443                                     enum AVHWFrameTransferDirection dir,
444                                     enum AVPixelFormat **formats, int flags);
445 
446 
447 /**
448  * This struct describes the constraints on hardware frames attached to
449  * a given device with a hardware-specific configuration.  This is returned
450  * by av_hwdevice_get_hwframe_constraints() and must be freed by
451  * av_hwframe_constraints_free() after use.
452  */
453 typedef struct AVHWFramesConstraints {
454     /**
455      * A list of possible values for format in the hw_frames_ctx,
456      * terminated by AV_PIX_FMT_NONE.  This member will always be filled.
457      */
458     enum AVPixelFormat *valid_hw_formats;
459 
460     /**
461      * A list of possible values for sw_format in the hw_frames_ctx,
462      * terminated by AV_PIX_FMT_NONE.  Can be NULL if this information is
463      * not known.
464      */
465     enum AVPixelFormat *valid_sw_formats;
466 
467     /**
468      * The minimum size of frames in this hw_frames_ctx.
469      * (Zero if not known.)
470      */
471     int min_width;
472     int min_height;
473 
474     /**
475      * The maximum size of frames in this hw_frames_ctx.
476      * (INT_MAX if not known / no limit.)
477      */
478     int max_width;
479     int max_height;
480 } AVHWFramesConstraints;
481 
482 /**
483  * Allocate a HW-specific configuration structure for a given HW device.
484  * After use, the user must free all members as required by the specific
485  * hardware structure being used, then free the structure itself with
486  * av_free().
487  *
488  * @param device_ctx a reference to the associated AVHWDeviceContext.
489  * @return The newly created HW-specific configuration structure on
490  *         success or NULL on failure.
491  */
492 void *av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx);
493 
494 /**
495  * Get the constraints on HW frames given a device and the HW-specific
496  * configuration to be used with that device.  If no HW-specific
497  * configuration is provided, returns the maximum possible capabilities
498  * of the device.
499  *
500  * @param ref a reference to the associated AVHWDeviceContext.
501  * @param hwconfig a filled HW-specific configuration structure, or NULL
502  *        to return the maximum possible capabilities of the device.
503  * @return AVHWFramesConstraints structure describing the constraints
504  *         on the device, or NULL if not available.
505  */
506 AVHWFramesConstraints *av_hwdevice_get_hwframe_constraints(AVBufferRef *ref,
507                                                            const void *hwconfig);
508 
509 /**
510  * Free an AVHWFrameConstraints structure.
511  *
512  * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
513  */
514 void av_hwframe_constraints_free(AVHWFramesConstraints **constraints);
515 
516 
517 /**
518  * Flags to apply to frame mappings.
519  */
520 enum {
521     /**
522      * The mapping must be readable.
523      */
524     AV_HWFRAME_MAP_READ      = 1 << 0,
525     /**
526      * The mapping must be writeable.
527      */
528     AV_HWFRAME_MAP_WRITE     = 1 << 1,
529     /**
530      * The mapped frame will be overwritten completely in subsequent
531      * operations, so the current frame data need not be loaded.  Any values
532      * which are not overwritten are unspecified.
533      */
534     AV_HWFRAME_MAP_OVERWRITE = 1 << 2,
535     /**
536      * The mapping must be direct.  That is, there must not be any copying in
537      * the map or unmap steps.  Note that performance of direct mappings may
538      * be much lower than normal memory.
539      */
540     AV_HWFRAME_MAP_DIRECT    = 1 << 3,
541 };
542 
543 /**
544  * Map a hardware frame.
545  *
546  * This has a number of different possible effects, depending on the format
547  * and origin of the src and dst frames.  On input, src should be a usable
548  * frame with valid buffers and dst should be blank (typically as just created
549  * by av_frame_alloc()).  src should have an associated hwframe context, and
550  * dst may optionally have a format and associated hwframe context.
551  *
552  * If src was created by mapping a frame from the hwframe context of dst,
553  * then this function undoes the mapping - dst is replaced by a reference to
554  * the frame that src was originally mapped from.
555  *
556  * If both src and dst have an associated hwframe context, then this function
557  * attempts to map the src frame from its hardware context to that of dst and
558  * then fill dst with appropriate data to be usable there.  This will only be
559  * possible if the hwframe contexts and associated devices are compatible -
560  * given compatible devices, av_hwframe_ctx_create_derived() can be used to
561  * create a hwframe context for dst in which mapping should be possible.
562  *
563  * If src has a hwframe context but dst does not, then the src frame is
564  * mapped to normal memory and should thereafter be usable as a normal frame.
565  * If the format is set on dst, then the mapping will attempt to create dst
566  * with that format and fail if it is not possible.  If format is unset (is
567  * AV_PIX_FMT_NONE) then dst will be mapped with whatever the most appropriate
568  * format to use is (probably the sw_format of the src hwframe context).
569  *
570  * A return value of AVERROR(ENOSYS) indicates that the mapping is not
571  * possible with the given arguments and hwframe setup, while other return
572  * values indicate that it failed somehow.
573  *
574  * @param dst Destination frame, to contain the mapping.
575  * @param src Source frame, to be mapped.
576  * @param flags Some combination of AV_HWFRAME_MAP_* flags.
577  * @return Zero on success, negative AVERROR code on failure.
578  */
579 int av_hwframe_map(AVFrame *dst, const AVFrame *src, int flags);
580 
581 
582 /**
583  * Create and initialise an AVHWFramesContext as a mapping of another existing
584  * AVHWFramesContext on a different device.
585  *
586  * av_hwframe_ctx_init() should not be called after this.
587  *
588  * @param derived_frame_ctx  On success, a reference to the newly created
589  *                           AVHWFramesContext.
590  * @param derived_device_ctx A reference to the device to create the new
591  *                           AVHWFramesContext on.
592  * @param source_frame_ctx   A reference to an existing AVHWFramesContext
593  *                           which will be mapped to the derived context.
594  * @param flags  Some combination of AV_HWFRAME_MAP_* flags, defining the
595  *               mapping parameters to apply to frames which are allocated
596  *               in the derived device.
597  * @return       Zero on success, negative AVERROR code on failure.
598  */
599 int av_hwframe_ctx_create_derived(AVBufferRef **derived_frame_ctx,
600                                   enum AVPixelFormat format,
601                                   AVBufferRef *derived_device_ctx,
602                                   AVBufferRef *source_frame_ctx,
603                                   int flags);
604 
605 #endif /* AVUTIL_HWCONTEXT_H */
606