FFmpeg  4.0
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 
39 };
40 
42 
43 /**
44  * This struct aggregates all the (hardware/vendor-specific) "high-level" state,
45  * i.e. state that is not tied to a concrete processing configuration.
46  * E.g., in an API that supports hardware-accelerated encoding and decoding,
47  * this struct will (if possible) wrap the state that is common to both encoding
48  * and decoding and from which specific instances of encoders or decoders can be
49  * derived.
50  *
51  * This struct is reference-counted with the AVBuffer mechanism. The
52  * av_hwdevice_ctx_alloc() constructor yields a reference, whose data field
53  * points to the actual AVHWDeviceContext. Further objects derived from
54  * AVHWDeviceContext (such as AVHWFramesContext, describing a frame pool with
55  * specific properties) will hold an internal reference to it. After all the
56  * references are released, the AVHWDeviceContext itself will be freed,
57  * optionally invoking a user-specified callback for uninitializing the hardware
58  * state.
59  */
60 typedef struct AVHWDeviceContext {
61  /**
62  * A class for logging. Set by av_hwdevice_ctx_alloc().
63  */
64  const AVClass *av_class;
65 
66  /**
67  * Private data used internally by libavutil. Must not be accessed in any
68  * way by the caller.
69  */
70  AVHWDeviceInternal *internal;
71 
72  /**
73  * This field identifies the underlying API used for hardware access.
74  *
75  * This field is set when this struct is allocated and never changed
76  * afterwards.
77  */
79 
80  /**
81  * The format-specific data, allocated and freed by libavutil along with
82  * this context.
83  *
84  * Should be cast by the user to the format-specific context defined in the
85  * corresponding header (hwcontext_*.h) and filled as described in the
86  * documentation before calling av_hwdevice_ctx_init().
87  *
88  * After calling av_hwdevice_ctx_init() this struct should not be modified
89  * by the caller.
90  */
91  void *hwctx;
92 
93  /**
94  * This field may be set by the caller before calling av_hwdevice_ctx_init().
95  *
96  * If non-NULL, this callback will be called when the last reference to
97  * this context is unreferenced, immediately before it is freed.
98  *
99  * @note when other objects (e.g an AVHWFramesContext) are derived from this
100  * struct, this callback will be invoked after all such child objects
101  * are fully uninitialized and their respective destructors invoked.
102  */
104 
105  /**
106  * Arbitrary user data, to be used e.g. by the free() callback.
107  */
108  void *user_opaque;
110 
112 
113 /**
114  * This struct describes a set or pool of "hardware" frames (i.e. those with
115  * data not located in normal system memory). All the frames in the pool are
116  * assumed to be allocated in the same way and interchangeable.
117  *
118  * This struct is reference-counted with the AVBuffer mechanism and tied to a
119  * given AVHWDeviceContext instance. The av_hwframe_ctx_alloc() constructor
120  * yields a reference, whose data field points to the actual AVHWFramesContext
121  * struct.
122  */
123 typedef struct AVHWFramesContext {
124  /**
125  * A class for logging.
126  */
128 
129  /**
130  * Private data used internally by libavutil. Must not be accessed in any
131  * way by the caller.
132  */
134 
135  /**
136  * A reference to the parent AVHWDeviceContext. This reference is owned and
137  * managed by the enclosing AVHWFramesContext, but the caller may derive
138  * additional references from it.
139  */
141 
142  /**
143  * The parent AVHWDeviceContext. This is simply a pointer to
144  * device_ref->data provided for convenience.
145  *
146  * Set by libavutil in av_hwframe_ctx_init().
147  */
149 
150  /**
151  * The format-specific data, allocated and freed automatically along with
152  * this context.
153  *
154  * Should be cast by the user to the format-specific context defined in the
155  * corresponding header (hwframe_*.h) and filled as described in the
156  * documentation before calling av_hwframe_ctx_init().
157  *
158  * After any frames using this context are created, the contents of this
159  * struct should not be modified by the caller.
160  */
161  void *hwctx;
162 
163  /**
164  * This field may be set by the caller before calling av_hwframe_ctx_init().
165  *
166  * If non-NULL, this callback will be called when the last reference to
167  * this context is unreferenced, immediately before it is freed.
168  */
170 
171  /**
172  * Arbitrary user data, to be used e.g. by the free() callback.
173  */
174  void *user_opaque;
175 
176  /**
177  * A pool from which the frames are allocated by av_hwframe_get_buffer().
178  * This field may be set by the caller before calling av_hwframe_ctx_init().
179  * The buffers returned by calling av_buffer_pool_get() on this pool must
180  * have the properties described in the documentation in the corresponding hw
181  * type's header (hwcontext_*.h). The pool will be freed strictly before
182  * this struct's free() callback is invoked.
183  *
184  * This field may be NULL, then libavutil will attempt to allocate a pool
185  * internally. Note that certain device types enforce pools allocated at
186  * fixed size (frame count), which cannot be extended dynamically. In such a
187  * case, initial_pool_size must be set appropriately.
188  */
190 
191  /**
192  * Initial size of the frame pool. If a device type does not support
193  * dynamically resizing the pool, then this is also the maximum pool size.
194  *
195  * May be set by the caller before calling av_hwframe_ctx_init(). Must be
196  * set if pool is NULL and the device type does not support dynamic pools.
197  */
199 
200  /**
201  * The pixel format identifying the underlying HW surface type.
202  *
203  * Must be a hwaccel format, i.e. the corresponding descriptor must have the
204  * AV_PIX_FMT_FLAG_HWACCEL flag set.
205  *
206  * Must be set by the user before calling av_hwframe_ctx_init().
207  */
209 
210  /**
211  * The pixel format identifying the actual data layout of the hardware
212  * frames.
213  *
214  * Must be set by the caller before calling av_hwframe_ctx_init().
215  *
216  * @note when the underlying API does not provide the exact data layout, but
217  * only the colorspace/bit depth, this field should be set to the fully
218  * planar version of that format (e.g. for 8-bit 420 YUV it should be
219  * AV_PIX_FMT_YUV420P, not AV_PIX_FMT_NV12 or anything else).
220  */
222 
223  /**
224  * The allocated dimensions of the frames in this pool.
225  *
226  * Must be set by the user before calling av_hwframe_ctx_init().
227  */
228  int width, height;
230 
231 /**
232  * Look up an AVHWDeviceType by name.
233  *
234  * @param name String name of the device type (case-insensitive).
235  * @return The type from enum AVHWDeviceType, or AV_HWDEVICE_TYPE_NONE if
236  * not found.
237  */
239 
240 /** Get the string name of an AVHWDeviceType.
241  *
242  * @param type Type from enum AVHWDeviceType.
243  * @return Pointer to a static string containing the name, or NULL if the type
244  * is not valid.
245  */
247 
248 /**
249  * Iterate over supported device types.
250  *
251  * @param type AV_HWDEVICE_TYPE_NONE initially, then the previous type
252  * returned by this function in subsequent iterations.
253  * @return The next usable device type from enum AVHWDeviceType, or
254  * AV_HWDEVICE_TYPE_NONE if there are no more.
255  */
257 
258 /**
259  * Allocate an AVHWDeviceContext for a given hardware type.
260  *
261  * @param type the type of the hardware device to allocate.
262  * @return a reference to the newly created AVHWDeviceContext on success or NULL
263  * on failure.
264  */
266 
267 /**
268  * Finalize the device context before use. This function must be called after
269  * the context is filled with all the required information and before it is
270  * used in any way.
271  *
272  * @param ref a reference to the AVHWDeviceContext
273  * @return 0 on success, a negative AVERROR code on failure
274  */
276 
277 /**
278  * Open a device of the specified type and create an AVHWDeviceContext for it.
279  *
280  * This is a convenience function intended to cover the simple cases. Callers
281  * who need to fine-tune device creation/management should open the device
282  * manually and then wrap it in an AVHWDeviceContext using
283  * av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
284  *
285  * The returned context is already initialized and ready for use, the caller
286  * should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of
287  * the created AVHWDeviceContext are set by this function and should not be
288  * touched by the caller.
289  *
290  * @param device_ctx On success, a reference to the newly-created device context
291  * will be written here. The reference is owned by the caller
292  * and must be released with av_buffer_unref() when no longer
293  * needed. On failure, NULL will be written to this pointer.
294  * @param type The type of the device to create.
295  * @param device A type-specific string identifying the device to open.
296  * @param opts A dictionary of additional (type-specific) options to use in
297  * opening the device. The dictionary remains owned by the caller.
298  * @param flags currently unused
299  *
300  * @return 0 on success, a negative AVERROR code on failure.
301  */
303  const char *device, AVDictionary *opts, int flags);
304 
305 /**
306  * Create a new device of the specified type from an existing device.
307  *
308  * If the source device is a device of the target type or was originally
309  * derived from such a device (possibly through one or more intermediate
310  * devices of other types), then this will return a reference to the
311  * existing device of the same type as is requested.
312  *
313  * Otherwise, it will attempt to derive a new device from the given source
314  * device. If direct derivation to the new type is not implemented, it will
315  * attempt the same derivation from each ancestor of the source device in
316  * turn looking for an implemented derivation method.
317  *
318  * @param dst_ctx On success, a reference to the newly-created
319  * AVHWDeviceContext.
320  * @param type The type of the new device to create.
321  * @param src_ctx A reference to an existing AVHWDeviceContext which will be
322  * used to create the new device.
323  * @param flags Currently unused; should be set to zero.
324  * @return Zero on success, a negative AVERROR code on failure.
325  */
327  enum AVHWDeviceType type,
328  AVBufferRef *src_ctx, int flags);
329 
330 
331 /**
332  * Allocate an AVHWFramesContext tied to a given device context.
333  *
334  * @param device_ctx a reference to a AVHWDeviceContext. This function will make
335  * a new reference for internal use, the one passed to the
336  * function remains owned by the caller.
337  * @return a reference to the newly created AVHWFramesContext on success or NULL
338  * on failure.
339  */
341 
342 /**
343  * Finalize the context before use. This function must be called after the
344  * context is filled with all the required information and before it is attached
345  * to any frames.
346  *
347  * @param ref a reference to the AVHWFramesContext
348  * @return 0 on success, a negative AVERROR code on failure
349  */
351 
352 /**
353  * Allocate a new frame attached to the given AVHWFramesContext.
354  *
355  * @param hwframe_ctx a reference to an AVHWFramesContext
356  * @param frame an empty (freshly allocated or unreffed) frame to be filled with
357  * newly allocated buffers.
358  * @param flags currently unused, should be set to zero
359  * @return 0 on success, a negative AVERROR code on failure
360  */
361 int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags);
362 
363 /**
364  * Copy data to or from a hw surface. At least one of dst/src must have an
365  * AVHWFramesContext attached.
366  *
367  * If src has an AVHWFramesContext attached, then the format of dst (if set)
368  * must use one of the formats returned by av_hwframe_transfer_get_formats(src,
369  * AV_HWFRAME_TRANSFER_DIRECTION_FROM).
370  * If dst has an AVHWFramesContext attached, then the format of src must use one
371  * of the formats returned by av_hwframe_transfer_get_formats(dst,
372  * AV_HWFRAME_TRANSFER_DIRECTION_TO)
373  *
374  * dst may be "clean" (i.e. with data/buf pointers unset), in which case the
375  * data buffers will be allocated by this function using av_frame_get_buffer().
376  * If dst->format is set, then this format will be used, otherwise (when
377  * dst->format is AV_PIX_FMT_NONE) the first acceptable format will be chosen.
378  *
379  * The two frames must have matching allocated dimensions (i.e. equal to
380  * AVHWFramesContext.width/height), since not all device types support
381  * transferring a sub-rectangle of the whole surface. The display dimensions
382  * (i.e. AVFrame.width/height) may be smaller than the allocated dimensions, but
383  * also have to be equal for both frames. When the display dimensions are
384  * smaller than the allocated dimensions, the content of the padding in the
385  * destination frame is unspecified.
386  *
387  * @param dst the destination frame. dst is not touched on failure.
388  * @param src the source frame.
389  * @param flags currently unused, should be set to zero
390  * @return 0 on success, a negative AVERROR error code on failure.
391  */
392 int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags);
393 
395  /**
396  * Transfer the data from the queried hw frame.
397  */
399 
400  /**
401  * Transfer the data to the queried hw frame.
402  */
404 };
405 
406 /**
407  * Get a list of possible source or target formats usable in
408  * av_hwframe_transfer_data().
409  *
410  * @param hwframe_ctx the frame context to obtain the information for
411  * @param dir the direction of the transfer
412  * @param formats the pointer to the output format list will be written here.
413  * The list is terminated with AV_PIX_FMT_NONE and must be freed
414  * by the caller when no longer needed using av_free().
415  * If this function returns successfully, the format list will
416  * have at least one item (not counting the terminator).
417  * On failure, the contents of this pointer are unspecified.
418  * @param flags currently unused, should be set to zero
419  * @return 0 on success, a negative AVERROR code on failure.
420  */
423  enum AVPixelFormat **formats, int flags);
424 
425 
426 /**
427  * This struct describes the constraints on hardware frames attached to
428  * a given device with a hardware-specific configuration. This is returned
429  * by av_hwdevice_get_hwframe_constraints() and must be freed by
430  * av_hwframe_constraints_free() after use.
431  */
432 typedef struct AVHWFramesConstraints {
433  /**
434  * A list of possible values for format in the hw_frames_ctx,
435  * terminated by AV_PIX_FMT_NONE. This member will always be filled.
436  */
438 
439  /**
440  * A list of possible values for sw_format in the hw_frames_ctx,
441  * terminated by AV_PIX_FMT_NONE. Can be NULL if this information is
442  * not known.
443  */
445 
446  /**
447  * The minimum size of frames in this hw_frames_ctx.
448  * (Zero if not known.)
449  */
452 
453  /**
454  * The maximum size of frames in this hw_frames_ctx.
455  * (INT_MAX if not known / no limit.)
456  */
460 
461 /**
462  * Allocate a HW-specific configuration structure for a given HW device.
463  * After use, the user must free all members as required by the specific
464  * hardware structure being used, then free the structure itself with
465  * av_free().
466  *
467  * @param device_ctx a reference to the associated AVHWDeviceContext.
468  * @return The newly created HW-specific configuration structure on
469  * success or NULL on failure.
470  */
471 void *av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx);
472 
473 /**
474  * Get the constraints on HW frames given a device and the HW-specific
475  * configuration to be used with that device. If no HW-specific
476  * configuration is provided, returns the maximum possible capabilities
477  * of the device.
478  *
479  * @param ref a reference to the associated AVHWDeviceContext.
480  * @param hwconfig a filled HW-specific configuration structure, or NULL
481  * to return the maximum possible capabilities of the device.
482  * @return AVHWFramesConstraints structure describing the constraints
483  * on the device, or NULL if not available.
484  */
486  const void *hwconfig);
487 
488 /**
489  * Free an AVHWFrameConstraints structure.
490  *
491  * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
492  */
494 
495 
496 /**
497  * Flags to apply to frame mappings.
498  */
499 enum {
500  /**
501  * The mapping must be readable.
502  */
504  /**
505  * The mapping must be writeable.
506  */
508  /**
509  * The mapped frame will be overwritten completely in subsequent
510  * operations, so the current frame data need not be loaded. Any values
511  * which are not overwritten are unspecified.
512  */
514  /**
515  * The mapping must be direct. That is, there must not be any copying in
516  * the map or unmap steps. Note that performance of direct mappings may
517  * be much lower than normal memory.
518  */
520 };
521 
522 /**
523  * Map a hardware frame.
524  *
525  * This has a number of different possible effects, depending on the format
526  * and origin of the src and dst frames. On input, src should be a usable
527  * frame with valid buffers and dst should be blank (typically as just created
528  * by av_frame_alloc()). src should have an associated hwframe context, and
529  * dst may optionally have a format and associated hwframe context.
530  *
531  * If src was created by mapping a frame from the hwframe context of dst,
532  * then this function undoes the mapping - dst is replaced by a reference to
533  * the frame that src was originally mapped from.
534  *
535  * If both src and dst have an associated hwframe context, then this function
536  * attempts to map the src frame from its hardware context to that of dst and
537  * then fill dst with appropriate data to be usable there. This will only be
538  * possible if the hwframe contexts and associated devices are compatible -
539  * given compatible devices, av_hwframe_ctx_create_derived() can be used to
540  * create a hwframe context for dst in which mapping should be possible.
541  *
542  * If src has a hwframe context but dst does not, then the src frame is
543  * mapped to normal memory and should thereafter be usable as a normal frame.
544  * If the format is set on dst, then the mapping will attempt to create dst
545  * with that format and fail if it is not possible. If format is unset (is
546  * AV_PIX_FMT_NONE) then dst will be mapped with whatever the most appropriate
547  * format to use is (probably the sw_format of the src hwframe context).
548  *
549  * A return value of AVERROR(ENOSYS) indicates that the mapping is not
550  * possible with the given arguments and hwframe setup, while other return
551  * values indicate that it failed somehow.
552  *
553  * @param dst Destination frame, to contain the mapping.
554  * @param src Source frame, to be mapped.
555  * @param flags Some combination of AV_HWFRAME_MAP_* flags.
556  * @return Zero on success, negative AVERROR code on failure.
557  */
558 int av_hwframe_map(AVFrame *dst, const AVFrame *src, int flags);
559 
560 
561 /**
562  * Create and initialise an AVHWFramesContext as a mapping of another existing
563  * AVHWFramesContext on a different device.
564  *
565  * av_hwframe_ctx_init() should not be called after this.
566  *
567  * @param derived_frame_ctx On success, a reference to the newly created
568  * AVHWFramesContext.
569  * @param derived_device_ctx A reference to the device to create the new
570  * AVHWFramesContext on.
571  * @param source_frame_ctx A reference to an existing AVHWFramesContext
572  * which will be mapped to the derived context.
573  * @param flags Some combination of AV_HWFRAME_MAP_* flags, defining the
574  * mapping parameters to apply to frames which are allocated
575  * in the derived device.
576  * @return Zero on success, negative AVERROR code on failure.
577  */
578 int av_hwframe_ctx_create_derived(AVBufferRef **derived_frame_ctx,
579  enum AVPixelFormat format,
580  AVBufferRef *derived_device_ctx,
581  AVBufferRef *source_frame_ctx,
582  int flags);
583 
584 #endif /* AVUTIL_HWCONTEXT_H */
const char * name
Definition: avisynth_c.h:775
This struct aggregates all the (hardware/vendor-specific) "high-level" state, i.e.
Definition: hwcontext.h:60
static const char * format[]
Definition: af_aiir.c:311
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
void av_hwframe_constraints_free(AVHWFramesConstraints **constraints)
Free an AVHWFrameConstraints structure.
Definition: hwcontext.c:562
enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev)
Iterate over supported device types.
Definition: hwcontext.c:97
int width
The allocated dimensions of the frames in this pool.
Definition: hwcontext.h:228
void * user_opaque
Arbitrary user data, to be used e.g.
Definition: hwcontext.h:174
#define src
Definition: vp8dsp.c:254
int max_width
The maximum size of frames in this hw_frames_ctx.
Definition: hwcontext.h:457
AVBufferRef * av_hwframe_ctx_alloc(AVBufferRef *device_ctx)
Allocate an AVHWFramesContext tied to a given device context.
Definition: hwcontext.c:243
enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name)
Look up an AVHWDeviceType by name.
Definition: hwcontext.c:78
int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags)
Copy data to or from a hw surface.
Definition: hwcontext.c:439
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:537
static AVFrame * frame
void * hwctx
The format-specific data, allocated and freed by libavutil along with this context.
Definition: hwcontext.h:91
#define height
static int flags
Definition: log.c:55
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:381
The mapped frame will be overwritten completely in subsequent operations, so the current frame data n...
Definition: hwcontext.h:513
The buffer pool.
const AVClass * av_class
A class for logging.
Definition: hwcontext.h:127
AVBufferRef * av_hwdevice_ctx_alloc(enum AVHWDeviceType type)
Allocate an AVHWDeviceContext for a given hardware type.
Definition: hwcontext.c:138
The mapping must be direct.
Definition: hwcontext.h:519
int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags)
Allocate a new frame attached to the given AVHWFramesContext.
Definition: hwcontext.c:465
enum AVHWDeviceType type
This field identifies the underlying API used for hardware access.
Definition: hwcontext.h:78
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:799
reference-counted frame API
int initial_pool_size
Initial size of the frame pool.
Definition: hwcontext.h:198
AVDictionary * opts
Definition: movenc.c:50
Transfer the data from the queried hw frame.
Definition: hwcontext.h:398
AVHWDeviceContext * device_ctx
The parent AVHWDeviceContext.
Definition: hwcontext.h:148
The mapping must be readable.
Definition: hwcontext.h:503
AVFormatContext * ctx
Definition: movenc.c:48
The mapping must be writeable.
Definition: hwcontext.h:507
int av_hwframe_ctx_init(AVBufferRef *ref)
Finalize the context before use.
Definition: hwcontext.c:329
int av_hwframe_map(AVFrame *dst, const AVFrame *src, int flags)
Map a hardware frame.
Definition: hwcontext.c:741
int min_width
The minimum size of frames in this hw_frames_ctx.
Definition: hwcontext.h:450
Transfer the data to the queried hw frame.
Definition: hwcontext.h:403
typedef void(RENAME(mix_any_func_type))
This struct describes the constraints on hardware frames attached to a given device with a hardware-s...
Definition: hwcontext.h:432
int av_hwdevice_ctx_init(AVBufferRef *ref)
Finalize the device context before use.
Definition: hwcontext.c:196
void * hwctx
The format-specific data, allocated and freed automatically along with this context.
Definition: hwcontext.h:161
const AVClass * av_class
A class for logging.
Definition: hwcontext.h:64
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:607
This struct describes a set or pool of "hardware" frames (i.e.
Definition: hwcontext.h:123
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:437
const char * av_hwdevice_get_type_name(enum AVHWDeviceType type)
Get the string name of an AVHWDeviceType.
Definition: hwcontext.c:88
void * user_opaque
Arbitrary user data, to be used e.g.
Definition: hwcontext.h:108
AVBufferRef * device_ref
A reference to the parent AVHWDeviceContext.
Definition: hwcontext.h:140
A reference to a data buffer.
Definition: buffer.h:81
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:107
AVHWFrameTransferDirection
Definition: hwcontext.h:394
pixel format definitions
AVBufferPool * pool
A pool from which the frames are allocated by av_hwframe_get_buffer().
Definition: hwcontext.h:189
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:571
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:444
void(* free)(struct AVHWDeviceContext *ctx)
This field may be set by the caller before calling av_hwdevice_ctx_init().
Definition: hwcontext.h:103
formats
Definition: signature.h:48
void * av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx)
Allocate a HW-specific configuration structure for a given HW device.
Definition: hwcontext.c:526
enum AVPixelFormat sw_format
The pixel format identifying the actual data layout of the hardware frames.
Definition: hwcontext.h:221
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60