FFmpeg
hwcontext.h
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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 
40 };
41 
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  */
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  */
105 
106  /**
107  * Arbitrary user data, to be used e.g. by the free() callback.
108  */
109  void *user_opaque;
111 
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  */
129 
130  /**
131  * Private data used internally by libavutil. Must not be accessed in any
132  * way by the caller.
133  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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;
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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 
416  /**
417  * Transfer the data from the queried hw frame.
418  */
420 
421  /**
422  * Transfer the data to the queried hw frame.
423  */
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  */
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  */
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  */
466 
467  /**
468  * The minimum size of frames in this hw_frames_ctx.
469  * (Zero if not known.)
470  */
473 
474  /**
475  * The maximum size of frames in this hw_frames_ctx.
476  * (INT_MAX if not known / no limit.)
477  */
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  */
507  const void *hwconfig);
508 
509 /**
510  * Free an AVHWFrameConstraints structure.
511  *
512  * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
513  */
515 
516 
517 /**
518  * Flags to apply to frame mappings.
519  */
520 enum {
521  /**
522  * The mapping must be readable.
523  */
525  /**
526  * The mapping must be writeable.
527  */
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  */
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  */
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 */
This struct aggregates all the (hardware/vendor-specific) "high-level" state, i.e.
Definition: hwcontext.h:61
This structure describes decoded (raw) audio or video data.
Definition: frame.h:308
void av_hwframe_constraints_free(AVHWFramesConstraints **constraints)
Free an AVHWFrameConstraints structure.
Definition: hwcontext.c:601
enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev)
Iterate over supported device types.
Definition: hwcontext.c:101
int width
The allocated dimensions of the frames in this pool.
Definition: hwcontext.h:229
GLint GLenum type
Definition: opengl_enc.c:104
void * user_opaque
Arbitrary user data, to be used e.g.
Definition: hwcontext.h:175
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample format(the sample packing is implied by the sample format) and sample rate.The lists are not just lists
int max_width
The maximum size of frames in this hw_frames_ctx.
Definition: hwcontext.h:478
AVBufferRef * av_hwframe_ctx_alloc(AVBufferRef *device_ctx)
Allocate an AVHWFramesContext tied to a given device context.
Definition: hwcontext.c:247
enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name)
Look up an AVHWDeviceType by name.
Definition: hwcontext.c:82
The mapping must be readable.
Definition: hwcontext.h:524
int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags)
Copy data to or from a hw surface.
Definition: hwcontext.c:443
AVHWFramesConstraints * av_hwdevice_get_hwframe_constraints(AVBufferRef *ref, const void *hwconfig)
Get the constraints on HW frames given a device and the HW-specific configuration to be used with tha...
Definition: hwcontext.c:576
void * hwctx
The format-specific data, allocated and freed by libavutil along with this context.
Definition: hwcontext.h:92
#define height
int av_hwframe_transfer_get_formats(AVBufferRef *hwframe_ctx, enum AVHWFrameTransferDirection dir, enum AVPixelFormat **formats, int flags)
Get a list of possible source or target formats usable in av_hwframe_transfer_data().
Definition: hwcontext.c:385
The buffer pool.
const AVClass * av_class
A class for logging.
Definition: hwcontext.h:128
#define src
Definition: vp8dsp.c:254
int av_hwdevice_ctx_create_derived_opts(AVBufferRef **dst_ctx, enum AVHWDeviceType type, AVBufferRef *src_ctx, AVDictionary *options, int flags)
Create a new device of the specified type from an existing device.
Definition: hwcontext.c:646
AVBufferRef * av_hwdevice_ctx_alloc(enum AVHWDeviceType type)
Allocate an AVHWDeviceContext for a given hardware type.
Definition: hwcontext.c:142
int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags)
Allocate a new frame attached to the given AVHWFramesContext.
Definition: hwcontext.c:502
enum AVHWDeviceType type
This field identifies the underlying API used for hardware access.
Definition: hwcontext.h:79
int av_hwframe_ctx_create_derived(AVBufferRef **derived_frame_ctx, enum AVPixelFormat format, AVBufferRef *derived_device_ctx, AVBufferRef *source_frame_ctx, int flags)
Create and initialise an AVHWFramesContext as a mapping of another existing AVHWFramesContext on a di...
Definition: hwcontext.c:847
reference-counted frame API
int initial_pool_size
Initial size of the frame pool.
Definition: hwcontext.h:199
AVDictionary * opts
Definition: movenc.c:50
Transfer the data from the queried hw frame.
Definition: hwcontext.h:419
AVHWDeviceContext * device_ctx
The parent AVHWDeviceContext.
Definition: hwcontext.h:149
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
AVFormatContext * ctx
Definition: movenc.c:48
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
int av_hwframe_ctx_init(AVBufferRef *ref)
Finalize the context before use.
Definition: hwcontext.c:333
int av_hwframe_map(AVFrame *dst, const AVFrame *src, int flags)
Map a hardware frame.
Definition: hwcontext.c:789
int min_width
The minimum size of frames in this hw_frames_ctx.
Definition: hwcontext.h:471
Transfer the data to the queried hw frame.
Definition: hwcontext.h:424
This struct describes the constraints on hardware frames attached to a given device with a hardware-s...
Definition: hwcontext.h:453
int av_hwdevice_ctx_init(AVBufferRef *ref)
Finalize the device context before use.
Definition: hwcontext.c:200
void * hwctx
The format-specific data, allocated and freed automatically along with this context.
Definition: hwcontext.h:162
const AVClass * av_class
A class for logging.
Definition: hwcontext.h:65
Describe the class of an AVClass context structure.
Definition: log.h:67
int av_hwdevice_ctx_create_derived(AVBufferRef **dst_ctx, enum AVHWDeviceType type, AVBufferRef *src_ctx, int flags)
Create a new device of the specified type from an existing device.
Definition: hwcontext.c:714
This struct describes a set or pool of "hardware" frames (i.e.
Definition: hwcontext.h:124
refcounted data buffer API
enum AVPixelFormat * valid_hw_formats
A list of possible values for format in the hw_frames_ctx, terminated by AV_PIX_FMT_NONE.
Definition: hwcontext.h:458
const char * av_hwdevice_get_type_name(enum AVHWDeviceType type)
Get the string name of an AVHWDeviceType.
Definition: hwcontext.c:92
#define flags(name, subs,...)
Definition: cbs_av1.c:560
void * user_opaque
Arbitrary user data, to be used e.g.
Definition: hwcontext.h:109
The mapping must be writeable.
Definition: hwcontext.h:528
AVBufferRef * device_ref
A reference to the parent AVHWDeviceContext.
Definition: hwcontext.h:141
A reference to a data buffer.
Definition: buffer.h:81
const OptionDef options[]
Definition: ffmpeg_opt.c:3392
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:107
AVHWFrameTransferDirection
Definition: hwcontext.h:415
pixel format definitions
AVBufferPool * pool
A pool from which the frames are allocated by av_hwframe_get_buffer().
Definition: hwcontext.h:190
AVHWDeviceType
Definition: hwcontext.h:27
int av_hwdevice_ctx_create(AVBufferRef **device_ctx, enum AVHWDeviceType type, const char *device, AVDictionary *opts, int flags)
Open a device of the specified type and create an AVHWDeviceContext for it.
Definition: hwcontext.c:610
enum AVPixelFormat * valid_sw_formats
A list of possible values for sw_format in the hw_frames_ctx, terminated by AV_PIX_FMT_NONE.
Definition: hwcontext.h:465
The mapping must be direct.
Definition: hwcontext.h:540
void(* free)(struct AVHWDeviceContext *ctx)
This field may be set by the caller before calling av_hwdevice_ctx_init().
Definition: hwcontext.h:104
formats
Definition: signature.h:48
The mapped frame will be overwritten completely in subsequent operations, so the current frame data n...
Definition: hwcontext.h:534
void * av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx)
Allocate a HW-specific configuration structure for a given HW device.
Definition: hwcontext.c:565
enum AVPixelFormat sw_format
The pixel format identifying the actual data layout of the hardware frames.
Definition: hwcontext.h:222
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
const char * name
Definition: opengl_enc.c:102