aboutsummaryrefslogtreecommitdiffstats
path: root/libavutil/hwcontext.h
blob: 4e9da0224d2517f2ae191575c1aafcc0bf09d569 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
/*
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVUTIL_HWCONTEXT_H
#define AVUTIL_HWCONTEXT_H

#include "buffer.h"
#include "frame.h"
#include "log.h"
#include "pixfmt.h"

enum AVHWDeviceType {
    AV_HWDEVICE_TYPE_VDPAU,
    AV_HWDEVICE_TYPE_CUDA,
    AV_HWDEVICE_TYPE_VAAPI,
    AV_HWDEVICE_TYPE_DXVA2,
};

typedef struct AVHWDeviceInternal AVHWDeviceInternal;

/**
 * This struct aggregates all the (hardware/vendor-specific) "high-level" state,
 * i.e. state that is not tied to a concrete processing configuration.
 * E.g., in an API that supports hardware-accelerated encoding and decoding,
 * this struct will (if possible) wrap the state that is common to both encoding
 * and decoding and from which specific instances of encoders or decoders can be
 * derived.
 *
 * This struct is reference-counted with the AVBuffer mechanism. The
 * av_hwdevice_ctx_alloc() constructor yields a reference, whose data field
 * points to the actual AVHWDeviceContext. Further objects derived from
 * AVHWDeviceContext (such as AVHWFramesContext, describing a frame pool with
 * specific properties) will hold an internal reference to it. After all the
 * references are released, the AVHWDeviceContext itself will be freed,
 * optionally invoking a user-specified callback for uninitializing the hardware
 * state.
 */
typedef struct AVHWDeviceContext {
    /**
     * A class for logging. Set by av_hwdevice_ctx_alloc().
     */
    const AVClass *av_class;

    /**
     * Private data used internally by libavutil. Must not be accessed in any
     * way by the caller.
     */
    AVHWDeviceInternal *internal;

    /**
     * This field identifies the underlying API used for hardware access.
     *
     * This field is set when this struct is allocated and never changed
     * afterwards.
     */
    enum AVHWDeviceType type;

    /**
     * The format-specific data, allocated and freed by libavutil along with
     * this context.
     *
     * Should be cast by the user to the format-specific context defined in the
     * corresponding header (hwcontext_*.h) and filled as described in the
     * documentation before calling av_hwdevice_ctx_init().
     *
     * After calling av_hwdevice_ctx_init() this struct should not be modified
     * by the caller.
     */
    void *hwctx;

    /**
     * This field may be set by the caller before calling av_hwdevice_ctx_init().
     *
     * If non-NULL, this callback will be called when the last reference to
     * this context is unreferenced, immediately before it is freed.
     *
     * @note when other objects (e.g an AVHWFramesContext) are derived from this
     *       struct, this callback will be invoked after all such child objects
     *       are fully uninitialized and their respective destructors invoked.
     */
    void (*free)(struct AVHWDeviceContext *ctx);

    /**
     * Arbitrary user data, to be used e.g. by the free() callback.
     */
    void *user_opaque;
} AVHWDeviceContext;

typedef struct AVHWFramesInternal AVHWFramesInternal;

/**
 * This struct describes a set or pool of "hardware" frames (i.e. those with
 * data not located in normal system memory). All the frames in the pool are
 * assumed to be allocated in the same way and interchangeable.
 *
 * This struct is reference-counted with the AVBuffer mechanism and tied to a
 * given AVHWDeviceContext instance. The av_hwframe_ctx_alloc() constructor
 * yields a reference, whose data field points to the actual AVHWFramesContext
 * struct.
 */
typedef struct AVHWFramesContext {
    /**
     * A class for logging.
     */
    const AVClass *av_class;

    /**
     * Private data used internally by libavutil. Must not be accessed in any
     * way by the caller.
     */
    AVHWFramesInternal *internal;

    /**
     * A reference to the parent AVHWDeviceContext. This reference is owned and
     * managed by the enclosing AVHWFramesContext, but the caller may derive
     * additional references from it.
     */
    AVBufferRef *device_ref;

    /**
     * The parent AVHWDeviceContext. This is simply a pointer to
     * device_ref->data provided for convenience.
     *
     * Set by libavutil in av_hwframe_ctx_init().
     */
    AVHWDeviceContext *device_ctx;

    /**
     * The format-specific data, allocated and freed automatically along with
     * this context.
     *
     * Should be cast by the user to the format-specific context defined in the
     * corresponding header (hwframe_*.h) and filled as described in the
     * documentation before calling av_hwframe_ctx_init().
     *
     * After any frames using this context are created, the contents of this
     * struct should not be modified by the caller.
     */
    void *hwctx;

    /**
     * This field may be set by the caller before calling av_hwframe_ctx_init().
     *
     * If non-NULL, this callback will be called when the last reference to
     * this context is unreferenced, immediately before it is freed.
     */
    void (*free)(struct AVHWFramesContext *ctx);

    /**
     * Arbitrary user data, to be used e.g. by the free() callback.
     */
    void *user_opaque;

    /**
     * A pool from which the frames are allocated by av_hwframe_get_buffer().
     * This field may be set by the caller before calling av_hwframe_ctx_init().
     * The buffers returned by calling av_buffer_pool_get() on this pool must
     * have the properties described in the documentation in the corresponding hw
     * type's header (hwcontext_*.h). The pool will be freed strictly before
     * this struct's free() callback is invoked.
     *
     * This field may be NULL, then libavutil will attempt to allocate a pool
     * internally. Note that certain device types enforce pools allocated at
     * fixed size (frame count), which cannot be extended dynamically. In such a
     * case, initial_pool_size must be set appropriately.
     */
    AVBufferPool *pool;

    /**
     * Initial size of the frame pool. If a device type does not support
     * dynamically resizing the pool, then this is also the maximum pool size.
     *
     * May be set by the caller before calling av_hwframe_ctx_init(). Must be
     * set if pool is NULL and the device type does not support dynamic pools.
     */
    int initial_pool_size;

    /**
     * The pixel format identifying the underlying HW surface type.
     *
     * Must be a hwaccel format, i.e. the corresponding descriptor must have the
     * AV_PIX_FMT_FLAG_HWACCEL flag set.
     *
     * Must be set by the user before calling av_hwframe_ctx_init().
     */
    enum AVPixelFormat format;

    /**
     * The pixel format identifying the actual data layout of the hardware
     * frames.
     *
     * Must be set by the caller before calling av_hwframe_ctx_init().
     *
     * @note when the underlying API does not provide the exact data layout, but
     * only the colorspace/bit depth, this field should be set to the fully
     * planar version of that format (e.g. for 8-bit 420 YUV it should be
     * AV_PIX_FMT_YUV420P, not AV_PIX_FMT_NV12 or anything else).
     */
    enum AVPixelFormat sw_format;

    /**
     * The allocated dimensions of the frames in this pool.
     *
     * Must be set by the user before calling av_hwframe_ctx_init().
     */
    int width, height;
} AVHWFramesContext;

/**
 * Allocate an AVHWDeviceContext for a given pixel format.
 *
 * @param format a hwaccel pixel format (AV_PIX_FMT_FLAG_HWACCEL must be set
 *               on the corresponding format descriptor)
 * @return a reference to the newly created AVHWDeviceContext on success or NULL
 *         on failure.
 */
AVBufferRef *av_hwdevice_ctx_alloc(enum AVHWDeviceType type);

/**
 * Finalize the device context before use. This function must be called after
 * the context is filled with all the required information and before it is
 * used in any way.
 *
 * @param ref a reference to the AVHWDeviceContext
 * @return 0 on success, a negative AVERROR code on failure
 */
int av_hwdevice_ctx_init(AVBufferRef *ref);

/**
 * Open a device of the specified type and create an AVHWDeviceContext for it.
 *
 * This is a convenience function intended to cover the simple cases. Callers
 * who need to fine-tune device creation/management should open the device
 * manually and then wrap it in an AVHWDeviceContext using
 * av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
 *
 * The returned context is already initialized and ready for use, the caller
 * should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of
 * the created AVHWDeviceContext are set by this function and should not be
 * touched by the caller.
 *
 * @param device_ctx On success, a reference to the newly-created device context
 *                   will be written here. The reference is owned by the caller
 *                   and must be released with av_buffer_unref() when no longer
 *                   needed. On failure, NULL will be written to this pointer.
 * @param type The type of the device to create.
 * @param device A type-specific string identifying the device to open.
 * @param opts A dictionary of additional (type-specific) options to use in
 *             opening the device. The dictionary remains owned by the caller.
 * @param flags currently unused
 *
 * @return 0 on success, a negative AVERROR code on failure.
 */
int av_hwdevice_ctx_create(AVBufferRef **device_ctx, enum AVHWDeviceType type,
                           const char *device, AVDictionary *opts, int flags);

/**
 * Allocate an AVHWFramesContext tied to a given device context.
 *
 * @param device_ctx a reference to a AVHWDeviceContext. This function will make
 *                   a new reference for internal use, the one passed to the
 *                   function remains owned by the caller.
 * @return a reference to the newly created AVHWFramesContext on success or NULL
 *         on failure.
 */
AVBufferRef *av_hwframe_ctx_alloc(AVBufferRef *device_ctx);

/**
 * Finalize the context before use. This function must be called after the
 * context is filled with all the required information and before it is attached
 * to any frames.
 *
 * @param ref a reference to the AVHWFramesContext
 * @return 0 on success, a negative AVERROR code on failure
 */
int av_hwframe_ctx_init(AVBufferRef *ref);

/**
 * Allocate a new frame attached to the given AVHWFramesContext.
 *
 * @param hwframe_ctx a reference to an AVHWFramesContext
 * @param frame an empty (freshly allocated or unreffed) frame to be filled with
 *              newly allocated buffers.
 * @param flags currently unused, should be set to zero
 * @return 0 on success, a negative AVERROR code on failure
 */
int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags);

/**
 * Copy data to or from a hw surface. At least one of dst/src must have an
 * AVHWFramesContext attached.
 *
 * If src has an AVHWFramesContext attached, then the format of dst (if set)
 * must use one of the formats returned by av_hwframe_transfer_get_formats(src,
 * AV_HWFRAME_TRANSFER_DIRECTION_FROM).
 * If dst has an AVHWFramesContext attached, then the format of src must use one
 * of the formats returned by av_hwframe_transfer_get_formats(dst,
 * AV_HWFRAME_TRANSFER_DIRECTION_TO)
 *
 * dst may be "clean" (i.e. with data/buf pointers unset), in which case the
 * data buffers will be allocated by this function using av_frame_get_buffer().
 * If dst->format is set, then this format will be used, otherwise (when
 * dst->format is AV_PIX_FMT_NONE) the first acceptable format will be chosen.
 *
 * @param dst the destination frame. dst is not touched on failure.
 * @param src the source frame.
 * @param flags currently unused, should be set to zero
 * @return 0 on success, a negative AVERROR error code on failure.
 */
int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags);

enum AVHWFrameTransferDirection {
    /**
     * Transfer the data from the queried hw frame.
     */
    AV_HWFRAME_TRANSFER_DIRECTION_FROM,

    /**
     * Transfer the data to the queried hw frame.
     */
    AV_HWFRAME_TRANSFER_DIRECTION_TO,
};

/**
 * Get a list of possible source or target formats usable in
 * av_hwframe_transfer_data().
 *
 * @param hwframe_ctx the frame context to obtain the information for
 * @param dir the direction of the transfer
 * @param formats the pointer to the output format list will be written here.
 *                The list is terminated with AV_PIX_FMT_NONE and must be freed
 *                by the caller when no longer needed using av_free().
 *                If this function returns successfully, the format list will
 *                have at least one item (not counting the terminator).
 *                On failure, the contents of this pointer are unspecified.
 * @param flags currently unused, should be set to zero
 * @return 0 on success, a negative AVERROR code on failure.
 */
int av_hwframe_transfer_get_formats(AVBufferRef *hwframe_ctx,
                                    enum AVHWFrameTransferDirection dir,
                                    enum AVPixelFormat **formats, int flags);


/**
 * This struct describes the constraints on hardware frames attached to
 * a given device with a hardware-specific configuration.  This is returned
 * by av_hwdevice_get_hwframe_constraints() and must be freed by
 * av_hwframe_constraints_free() after use.
 */
typedef struct AVHWFramesConstraints {
    /**
     * A list of possible values for format in the hw_frames_ctx,
     * terminated by AV_PIX_FMT_NONE.  This member will always be filled.
     */
    enum AVPixelFormat *valid_hw_formats;

    /**
     * A list of possible values for sw_format in the hw_frames_ctx,
     * terminated by AV_PIX_FMT_NONE.  Can be NULL if this information is
     * not known.
     */
    enum AVPixelFormat *valid_sw_formats;

    /**
     * The minimum size of frames in this hw_frames_ctx.
     * (Zero if not known.)
     */
    int min_width;
    int min_height;

    /**
     * The maximum size of frames in this hw_frames_ctx.
     * (INT_MAX if not known / no limit.)
     */
    int max_width;
    int max_height;
} AVHWFramesConstraints;

/**
 * Allocate a HW-specific configuration structure for a given HW device.
 * After use, the user must free all members as required by the specific
 * hardware structure being used, then free the structure itself with
 * av_free().
 *
 * @param device_ctx a reference to the associated AVHWDeviceContext.
 * @return The newly created HW-specific configuration structure on
 *         success or NULL on failure.
 */
void *av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx);

/**
 * Get the constraints on HW frames given a device and the HW-specific
 * configuration to be used with that device.  If no HW-specific
 * configuration is provided, returns the maximum possible capabilities
 * of the device.
 *
 * @param device_ctx a reference to the associated AVHWDeviceContext.
 * @param hwconfig a filled HW-specific configuration structure, or NULL
 *        to return the maximum possible capabilities of the device.
 * @return AVHWFramesConstraints structure describing the constraints
 *         on the device, or NULL if not available.
 */
AVHWFramesConstraints *av_hwdevice_get_hwframe_constraints(AVBufferRef *ref,
                                                           const void *hwconfig);

/**
 * Free an AVHWFrameConstraints structure.
 *
 * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
 */
void av_hwframe_constraints_free(AVHWFramesConstraints **constraints);

#endif /* AVUTIL_HWCONTEXT_H */