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19 #ifndef AVUTIL_HWCONTEXT_H
20 #define AVUTIL_HWCONTEXT_H
28 AV_HWDEVICE_TYPE_VDPAU,
29 AV_HWDEVICE_TYPE_CUDA,
30 AV_HWDEVICE_TYPE_VAAPI,
31 AV_HWDEVICE_TYPE_DXVA2,
34 typedef struct AVHWDeviceInternal AVHWDeviceInternal;
37 * This struct aggregates all the (hardware/vendor-specific) "high-level" state,
38 * i.e. state that is not tied to a concrete processing configuration.
39 * E.g., in an API that supports hardware-accelerated encoding and decoding,
40 * this struct will (if possible) wrap the state that is common to both encoding
41 * and decoding and from which specific instances of encoders or decoders can be
44 * This struct is reference-counted with the AVBuffer mechanism. The
45 * av_hwdevice_ctx_alloc() constructor yields a reference, whose data field
46 * points to the actual AVHWDeviceContext. Further objects derived from
47 * AVHWDeviceContext (such as AVHWFramesContext, describing a frame pool with
48 * specific properties) will hold an internal reference to it. After all the
49 * references are released, the AVHWDeviceContext itself will be freed,
50 * optionally invoking a user-specified callback for uninitializing the hardware
53 typedef struct AVHWDeviceContext {
55 * A class for logging. Set by av_hwdevice_ctx_alloc().
57 const AVClass *av_class;
60 * Private data used internally by libavutil. Must not be accessed in any
63 AVHWDeviceInternal *internal;
66 * This field identifies the underlying API used for hardware access.
68 * This field is set when this struct is allocated and never changed
71 enum AVHWDeviceType type;
74 * The format-specific data, allocated and freed by libavutil along with
77 * Should be cast by the user to the format-specific context defined in the
78 * corresponding header (hwcontext_*.h) and filled as described in the
79 * documentation before calling av_hwdevice_ctx_init().
81 * After calling av_hwdevice_ctx_init() this struct should not be modified
87 * This field may be set by the caller before calling av_hwdevice_ctx_init().
89 * If non-NULL, this callback will be called when the last reference to
90 * this context is unreferenced, immediately before it is freed.
92 * @note when other objects (e.g an AVHWFramesContext) are derived from this
93 * struct, this callback will be invoked after all such child objects
94 * are fully uninitialized and their respective destructors invoked.
96 void (*free)(struct AVHWDeviceContext *ctx);
99 * Arbitrary user data, to be used e.g. by the free() callback.
104 typedef struct AVHWFramesInternal AVHWFramesInternal;
107 * This struct describes a set or pool of "hardware" frames (i.e. those with
108 * data not located in normal system memory). All the frames in the pool are
109 * assumed to be allocated in the same way and interchangeable.
111 * This struct is reference-counted with the AVBuffer mechanism and tied to a
112 * given AVHWDeviceContext instance. The av_hwframe_ctx_alloc() constructor
113 * yields a reference, whose data field points to the actual AVHWFramesContext
116 typedef struct AVHWFramesContext {
118 * A class for logging.
120 const AVClass *av_class;
123 * Private data used internally by libavutil. Must not be accessed in any
126 AVHWFramesInternal *internal;
129 * A reference to the parent AVHWDeviceContext. This reference is owned and
130 * managed by the enclosing AVHWFramesContext, but the caller may derive
131 * additional references from it.
133 AVBufferRef *device_ref;
136 * The parent AVHWDeviceContext. This is simply a pointer to
137 * device_ref->data provided for convenience.
139 * Set by libavutil in av_hwframe_ctx_init().
141 AVHWDeviceContext *device_ctx;
144 * The format-specific data, allocated and freed automatically along with
147 * Should be cast by the user to the format-specific context defined in the
148 * corresponding header (hwframe_*.h) and filled as described in the
149 * documentation before calling av_hwframe_ctx_init().
151 * After any frames using this context are created, the contents of this
152 * struct should not be modified by the caller.
157 * This field may be set by the caller before calling av_hwframe_ctx_init().
159 * If non-NULL, this callback will be called when the last reference to
160 * this context is unreferenced, immediately before it is freed.
162 void (*free)(struct AVHWFramesContext *ctx);
165 * Arbitrary user data, to be used e.g. by the free() callback.
170 * A pool from which the frames are allocated by av_hwframe_get_buffer().
171 * This field may be set by the caller before calling av_hwframe_ctx_init().
172 * The buffers returned by calling av_buffer_pool_get() on this pool must
173 * have the properties described in the documentation in the corresponding hw
174 * type's header (hwcontext_*.h). The pool will be freed strictly before
175 * this struct's free() callback is invoked.
177 * This field may be NULL, then libavutil will attempt to allocate a pool
178 * internally. Note that certain device types enforce pools allocated at
179 * fixed size (frame count), which cannot be extended dynamically. In such a
180 * case, initial_pool_size must be set appropriately.
185 * Initial size of the frame pool. If a device type does not support
186 * dynamically resizing the pool, then this is also the maximum pool size.
188 * May be set by the caller before calling av_hwframe_ctx_init(). Must be
189 * set if pool is NULL and the device type does not support dynamic pools.
191 int initial_pool_size;
194 * The pixel format identifying the underlying HW surface type.
196 * Must be a hwaccel format, i.e. the corresponding descriptor must have the
197 * AV_PIX_FMT_FLAG_HWACCEL flag set.
199 * Must be set by the user before calling av_hwframe_ctx_init().
201 enum AVPixelFormat format;
204 * The pixel format identifying the actual data layout of the hardware
207 * Must be set by the caller before calling av_hwframe_ctx_init().
209 * @note when the underlying API does not provide the exact data layout, but
210 * only the colorspace/bit depth, this field should be set to the fully
211 * planar version of that format (e.g. for 8-bit 420 YUV it should be
212 * AV_PIX_FMT_YUV420P, not AV_PIX_FMT_NV12 or anything else).
214 enum AVPixelFormat sw_format;
217 * The allocated dimensions of the frames in this pool.
219 * Must be set by the user before calling av_hwframe_ctx_init().
225 * Allocate an AVHWDeviceContext for a given pixel format.
227 * @param format a hwaccel pixel format (AV_PIX_FMT_FLAG_HWACCEL must be set
228 * on the corresponding format descriptor)
229 * @return a reference to the newly created AVHWDeviceContext on success or NULL
232 AVBufferRef *av_hwdevice_ctx_alloc(enum AVHWDeviceType type);
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
239 * @param ref a reference to the AVHWDeviceContext
240 * @return 0 on success, a negative AVERROR code on failure
242 int av_hwdevice_ctx_init(AVBufferRef *ref);
245 * Open a device of the specified type and create an AVHWDeviceContext for it.
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().
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.
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
267 * @return 0 on success, a negative AVERROR code on failure.
269 int av_hwdevice_ctx_create(AVBufferRef **device_ctx, enum AVHWDeviceType type,
270 const char *device, AVDictionary *opts, int flags);
273 * Allocate an AVHWFramesContext tied to a given device context.
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
281 AVBufferRef *av_hwframe_ctx_alloc(AVBufferRef *device_ctx);
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
288 * @param ref a reference to the AVHWFramesContext
289 * @return 0 on success, a negative AVERROR code on failure
291 int av_hwframe_ctx_init(AVBufferRef *ref);
294 * Allocate a new frame attached to the given AVHWFramesContext.
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
302 int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags);
305 * Copy data to or from a hw surface. At least one of dst/src must have an
306 * AVHWFramesContext attached.
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)
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.
320 * @param dst the destination frame. dst is not touched on failure.
321 * @param src the source frame.
322 * @param flags currently unused, should be set to zero
323 * @return 0 on success, a negative AVERROR error code on failure.
325 int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags);
327 enum AVHWFrameTransferDirection {
329 * Transfer the data from the queried hw frame.
331 AV_HWFRAME_TRANSFER_DIRECTION_FROM,
334 * Transfer the data to the queried hw frame.
336 AV_HWFRAME_TRANSFER_DIRECTION_TO,
340 * Get a list of possible source or target formats usable in
341 * av_hwframe_transfer_data().
343 * @param hwframe_ctx the frame context to obtain the information for
344 * @param dir the direction of the transfer
345 * @param formats the pointer to the output format list will be written here.
346 * The list is terminated with AV_PIX_FMT_NONE and must be freed
347 * by the caller when no longer needed using av_free().
348 * If this function returns successfully, the format list will
349 * have at least one item (not counting the terminator).
350 * On failure, the contents of this pointer are unspecified.
351 * @param flags currently unused, should be set to zero
352 * @return 0 on success, a negative AVERROR code on failure.
354 int av_hwframe_transfer_get_formats(AVBufferRef *hwframe_ctx,
355 enum AVHWFrameTransferDirection dir,
356 enum AVPixelFormat **formats, int flags);
360 * This struct describes the constraints on hardware frames attached to
361 * a given device with a hardware-specific configuration. This is returned
362 * by av_hwdevice_get_hwframe_constraints() and must be freed by
363 * av_hwframe_constraints_free() after use.
365 typedef struct AVHWFramesConstraints {
367 * A list of possible values for format in the hw_frames_ctx,
368 * terminated by AV_PIX_FMT_NONE. This member will always be filled.
370 enum AVPixelFormat *valid_hw_formats;
373 * A list of possible values for sw_format in the hw_frames_ctx,
374 * terminated by AV_PIX_FMT_NONE. Can be NULL if this information is
377 enum AVPixelFormat *valid_sw_formats;
380 * The minimum size of frames in this hw_frames_ctx.
381 * (Zero if not known.)
387 * The maximum size of frames in this hw_frames_ctx.
388 * (INT_MAX if not known / no limit.)
392 } AVHWFramesConstraints;
395 * Allocate a HW-specific configuration structure for a given HW device.
396 * After use, the user must free all members as required by the specific
397 * hardware structure being used, then free the structure itself with
400 * @param device_ctx a reference to the associated AVHWDeviceContext.
401 * @return The newly created HW-specific configuration structure on
402 * success or NULL on failure.
404 void *av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx);
407 * Get the constraints on HW frames given a device and the HW-specific
408 * configuration to be used with that device. If no HW-specific
409 * configuration is provided, returns the maximum possible capabilities
412 * @param device_ctx a reference to the associated AVHWDeviceContext.
413 * @param hwconfig a filled HW-specific configuration structure, or NULL
414 * to return the maximum possible capabilities of the device.
415 * @return AVHWFramesConstraints structure describing the constraints
416 * on the device, or NULL if not available.
418 AVHWFramesConstraints *av_hwdevice_get_hwframe_constraints(AVBufferRef *ref,
419 const void *hwconfig);
422 * Free an AVHWFrameConstraints structure.
424 * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
426 void av_hwframe_constraints_free(AVHWFramesConstraints **constraints);
428 #endif /* AVUTIL_HWCONTEXT_H */