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frame.h
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1 /*
2  *
3  * This file is part of FFmpeg.
4  *
5  * FFmpeg is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
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9  *
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12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * Lesser General Public License for more details.
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16  * License along with FFmpeg; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 /**
21  * @file
22  * @ingroup lavu_frame
23  * reference-counted frame API
24  */
25 
26 #ifndef AVUTIL_FRAME_H
27 #define AVUTIL_FRAME_H
28 
29 #include <stdint.h>
30 
31 #include "avutil.h"
32 #include "buffer.h"
33 #include "dict.h"
34 #include "rational.h"
35 #include "samplefmt.h"
36 #include "version.h"
37 
38 
41  AVCOL_SPC_BT709 = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 xvYCC709 / SMPTE RP177 Annex B
44  AVCOL_SPC_BT470BG = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM / IEC 61966-2-4 xvYCC601
45  AVCOL_SPC_SMPTE170M = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC / functionally identical to above
47  AVCOL_SPC_YCOCG = 8, ///< Used by Dirac / VC-2 and H.264 FRext, see ITU-T SG16
48  AVCOL_SPC_BT2020_NCL = 9, ///< ITU-R BT2020 non-constant luminance system
49  AVCOL_SPC_BT2020_CL = 10, ///< ITU-R BT2020 constant luminance system
50  AVCOL_SPC_NB , ///< Not part of ABI
51 };
52 #define AVCOL_SPC_YCGCO AVCOL_SPC_YCOCG
53 
56  AVCOL_RANGE_MPEG = 1, ///< the normal 219*2^(n-8) "MPEG" YUV ranges
57  AVCOL_RANGE_JPEG = 2, ///< the normal 2^n-1 "JPEG" YUV ranges
58  AVCOL_RANGE_NB , ///< Not part of ABI
59 };
60 
61 
62 /**
63  * @defgroup lavu_frame AVFrame
64  * @ingroup lavu_data
65  *
66  * @{
67  * AVFrame is an abstraction for reference-counted raw multimedia data.
68  */
69 
71  /**
72  * The data is the AVPanScan struct defined in libavcodec.
73  */
75  /**
76  * ATSC A53 Part 4 Closed Captions.
77  * A53 CC bitstream is stored as uint8_t in AVFrameSideData.data.
78  * The number of bytes of CC data is AVFrameSideData.size.
79  */
81  /**
82  * Stereoscopic 3d metadata.
83  * The data is the AVStereo3D struct defined in libavutil/stereo3d.h.
84  */
86  /**
87  * The data is the AVMatrixEncoding enum defined in libavutil/channel_layout.h.
88  */
90  /**
91  * Metadata relevant to a downmix procedure.
92  * The data is the AVDownmixInfo struct defined in libavutil/downmix_info.h.
93  */
95  /**
96  * ReplayGain information in the form of the AVReplayGain struct.
97  */
99 };
100 
101 typedef struct AVFrameSideData {
104  int size;
107 
108 /**
109  * This structure describes decoded (raw) audio or video data.
110  *
111  * AVFrame must be allocated using av_frame_alloc(). Note that this only
112  * allocates the AVFrame itself, the buffers for the data must be managed
113  * through other means (see below).
114  * AVFrame must be freed with av_frame_free().
115  *
116  * AVFrame is typically allocated once and then reused multiple times to hold
117  * different data (e.g. a single AVFrame to hold frames received from a
118  * decoder). In such a case, av_frame_unref() will free any references held by
119  * the frame and reset it to its original clean state before it
120  * is reused again.
121  *
122  * The data described by an AVFrame is usually reference counted through the
123  * AVBuffer API. The underlying buffer references are stored in AVFrame.buf /
124  * AVFrame.extended_buf. An AVFrame is considered to be reference counted if at
125  * least one reference is set, i.e. if AVFrame.buf[0] != NULL. In such a case,
126  * every single data plane must be contained in one of the buffers in
127  * AVFrame.buf or AVFrame.extended_buf.
128  * There may be a single buffer for all the data, or one separate buffer for
129  * each plane, or anything in between.
130  *
131  * sizeof(AVFrame) is not a part of the public ABI, so new fields may be added
132  * to the end with a minor bump.
133  * Similarly fields that are marked as to be only accessed by
134  * av_opt_ptr() can be reordered. This allows 2 forks to add fields
135  * without breaking compatibility with each other.
136  */
137 typedef struct AVFrame {
138 #define AV_NUM_DATA_POINTERS 8
139  /**
140  * pointer to the picture/channel planes.
141  * This might be different from the first allocated byte
142  *
143  * Some decoders access areas outside 0,0 - width,height, please
144  * see avcodec_align_dimensions2(). Some filters and swscale can read
145  * up to 16 bytes beyond the planes, if these filters are to be used,
146  * then 16 extra bytes must be allocated.
147  */
149 
150  /**
151  * For video, size in bytes of each picture line.
152  * For audio, size in bytes of each plane.
153  *
154  * For audio, only linesize[0] may be set. For planar audio, each channel
155  * plane must be the same size.
156  *
157  * For video the linesizes should be multiplies of the CPUs alignment
158  * preference, this is 16 or 32 for modern desktop CPUs.
159  * Some code requires such alignment other code can be slower without
160  * correct alignment, for yet other it makes no difference.
161  *
162  * @note The linesize may be larger than the size of usable data -- there
163  * may be extra padding present for performance reasons.
164  */
166 
167  /**
168  * pointers to the data planes/channels.
169  *
170  * For video, this should simply point to data[].
171  *
172  * For planar audio, each channel has a separate data pointer, and
173  * linesize[0] contains the size of each channel buffer.
174  * For packed audio, there is just one data pointer, and linesize[0]
175  * contains the total size of the buffer for all channels.
176  *
177  * Note: Both data and extended_data should always be set in a valid frame,
178  * but for planar audio with more channels that can fit in data,
179  * extended_data must be used in order to access all channels.
180  */
182 
183  /**
184  * width and height of the video frame
185  */
186  int width, height;
187 
188  /**
189  * number of audio samples (per channel) described by this frame
190  */
192 
193  /**
194  * format of the frame, -1 if unknown or unset
195  * Values correspond to enum AVPixelFormat for video frames,
196  * enum AVSampleFormat for audio)
197  */
198  int format;
199 
200  /**
201  * 1 -> keyframe, 0-> not
202  */
204 
205  /**
206  * Picture type of the frame.
207  */
209 
210 #if FF_API_AVFRAME_LAVC
213 #endif
214 
215  /**
216  * Sample aspect ratio for the video frame, 0/1 if unknown/unspecified.
217  */
219 
220  /**
221  * Presentation timestamp in time_base units (time when frame should be shown to user).
222  */
223  int64_t pts;
224 
225  /**
226  * PTS copied from the AVPacket that was decoded to produce this frame.
227  */
228  int64_t pkt_pts;
229 
230  /**
231  * DTS copied from the AVPacket that triggered returning this frame. (if frame threading isnt used)
232  * This is also the Presentation time of this AVFrame calculated from
233  * only AVPacket.dts values without pts values.
234  */
235  int64_t pkt_dts;
236 
237  /**
238  * picture number in bitstream order
239  */
241  /**
242  * picture number in display order
243  */
245 
246  /**
247  * quality (between 1 (good) and FF_LAMBDA_MAX (bad))
248  */
249  int quality;
250 
251 #if FF_API_AVFRAME_LAVC
254 
255  /**
256  * QP table
257  */
259  int8_t *qscale_table;
260  /**
261  * QP store stride
262  */
264  int qstride;
265 
268 
269  /**
270  * mbskip_table[mb]>=1 if MB didn't change
271  * stride= mb_width = (width+15)>>4
272  */
275 
276  /**
277  * motion vector table
278  * @code
279  * example:
280  * int mv_sample_log2= 4 - motion_subsample_log2;
281  * int mb_width= (width+15)>>4;
282  * int mv_stride= (mb_width << mv_sample_log2) + 1;
283  * motion_val[direction][x + y*mv_stride][0->mv_x, 1->mv_y];
284  * @endcode
285  */
286  int16_t (*motion_val[2])[2];
287 
288  /**
289  * macroblock type table
290  * mb_type_base + mb_width + 2
291  */
293  uint32_t *mb_type;
294 
295  /**
296  * DCT coefficients
297  */
299  short *dct_coeff;
300 
301  /**
302  * motion reference frame index
303  * the order in which these are stored can depend on the codec.
304  */
306  int8_t *ref_index[2];
307 #endif
308 
309  /**
310  * for some private data of the user
311  */
312  void *opaque;
313 
314  /**
315  * error
316  */
318 
319 #if FF_API_AVFRAME_LAVC
321  int type;
322 #endif
323 
324  /**
325  * When decoding, this signals how much the picture must be delayed.
326  * extra_delay = repeat_pict / (2*fps)
327  */
329 
330  /**
331  * The content of the picture is interlaced.
332  */
334 
335  /**
336  * If the content is interlaced, is top field displayed first.
337  */
339 
340  /**
341  * Tell user application that palette has changed from previous frame.
342  */
344 
345 #if FF_API_AVFRAME_LAVC
348 
349  /**
350  * Pan scan.
351  */
354 #endif
355 
356  /**
357  * reordered opaque 64bit (generally an integer or a double precision float
358  * PTS but can be anything).
359  * The user sets AVCodecContext.reordered_opaque to represent the input at
360  * that time,
361  * the decoder reorders values as needed and sets AVFrame.reordered_opaque
362  * to exactly one of the values provided by the user through AVCodecContext.reordered_opaque
363  * @deprecated in favor of pkt_pts
364  */
366 
367 #if FF_API_AVFRAME_LAVC
368  /**
369  * @deprecated this field is unused
370  */
372 
377 
378  /**
379  * log2 of the size of the block which a single vector in motion_val represents:
380  * (4->16x16, 3->8x8, 2-> 4x4, 1-> 2x2)
381  */
383 #endif
384 
385  /**
386  * Sample rate of the audio data.
387  */
389 
390  /**
391  * Channel layout of the audio data.
392  */
393  uint64_t channel_layout;
394 
395  /**
396  * AVBuffer references backing the data for this frame. If all elements of
397  * this array are NULL, then this frame is not reference counted.
398  *
399  * There may be at most one AVBuffer per data plane, so for video this array
400  * always contains all the references. For planar audio with more than
401  * AV_NUM_DATA_POINTERS channels, there may be more buffers than can fit in
402  * this array. Then the extra AVBufferRef pointers are stored in the
403  * extended_buf array.
404  */
406 
407  /**
408  * For planar audio which requires more than AV_NUM_DATA_POINTERS
409  * AVBufferRef pointers, this array will hold all the references which
410  * cannot fit into AVFrame.buf.
411  *
412  * Note that this is different from AVFrame.extended_data, which always
413  * contains all the pointers. This array only contains the extra pointers,
414  * which cannot fit into AVFrame.buf.
415  *
416  * This array is always allocated using av_malloc() by whoever constructs
417  * the frame. It is freed in av_frame_unref().
418  */
420  /**
421  * Number of elements in extended_buf.
422  */
424 
427 
428 /**
429  * @defgroup lavu_frame_flags AV_FRAME_FLAGS
430  * Flags describing additional frame properties.
431  *
432  * @{
433  */
434 
435 /**
436  * The frame data may be corrupted, e.g. due to decoding errors.
437  */
438 #define AV_FRAME_FLAG_CORRUPT (1 << 0)
439 /**
440  * @}
441  */
442 
443  /**
444  * Frame flags, a combination of @ref lavu_frame_flags
445  */
446  int flags;
447 
448  /**
449  * frame timestamp estimated using various heuristics, in stream time base
450  * Code outside libavcodec should access this field using:
451  * av_frame_get_best_effort_timestamp(frame)
452  * - encoding: unused
453  * - decoding: set by libavcodec, read by user.
454  */
456 
457  /**
458  * reordered pos from the last AVPacket that has been input into the decoder
459  * Code outside libavcodec should access this field using:
460  * av_frame_get_pkt_pos(frame)
461  * - encoding: unused
462  * - decoding: Read by user.
463  */
464  int64_t pkt_pos;
465 
466  /**
467  * duration of the corresponding packet, expressed in
468  * AVStream->time_base units, 0 if unknown.
469  * Code outside libavcodec should access this field using:
470  * av_frame_get_pkt_duration(frame)
471  * - encoding: unused
472  * - decoding: Read by user.
473  */
474  int64_t pkt_duration;
475 
476  /**
477  * metadata.
478  * Code outside libavcodec should access this field using:
479  * av_frame_get_metadata(frame)
480  * - encoding: Set by user.
481  * - decoding: Set by libavcodec.
482  */
484 
485  /**
486  * decode error flags of the frame, set to a combination of
487  * FF_DECODE_ERROR_xxx flags if the decoder produced a frame, but there
488  * were errors during the decoding.
489  * Code outside libavcodec should access this field using:
490  * av_frame_get_decode_error_flags(frame)
491  * - encoding: unused
492  * - decoding: set by libavcodec, read by user.
493  */
495 #define FF_DECODE_ERROR_INVALID_BITSTREAM 1
496 #define FF_DECODE_ERROR_MISSING_REFERENCE 2
497 
498  /**
499  * number of audio channels, only used for audio.
500  * Code outside libavcodec should access this field using:
501  * av_frame_get_channels(frame)
502  * - encoding: unused
503  * - decoding: Read by user.
504  */
505  int channels;
506 
507  /**
508  * size of the corresponding packet containing the compressed
509  * frame. It must be accessed using av_frame_get_pkt_size() and
510  * av_frame_set_pkt_size().
511  * It is set to a negative value if unknown.
512  * - encoding: unused
513  * - decoding: set by libavcodec, read by user.
514  */
515  int pkt_size;
516 
517  /**
518  * YUV colorspace type.
519  * It must be accessed using av_frame_get_colorspace() and
520  * av_frame_set_colorspace().
521  * - encoding: Set by user
522  * - decoding: Set by libavcodec
523  */
525 
526  /**
527  * MPEG vs JPEG YUV range.
528  * It must be accessed using av_frame_get_color_range() and
529  * av_frame_set_color_range().
530  * - encoding: Set by user
531  * - decoding: Set by libavcodec
532  */
534 
535 
536  /**
537  * Not to be accessed directly from outside libavutil
538  */
540 } AVFrame;
541 
542 /**
543  * Accessors for some AVFrame fields.
544  * The position of these field in the structure is not part of the ABI,
545  * they should not be accessed directly outside libavcodec.
546  */
549 int64_t av_frame_get_pkt_duration (const AVFrame *frame);
550 void av_frame_set_pkt_duration (AVFrame *frame, int64_t val);
551 int64_t av_frame_get_pkt_pos (const AVFrame *frame);
552 void av_frame_set_pkt_pos (AVFrame *frame, int64_t val);
553 int64_t av_frame_get_channel_layout (const AVFrame *frame);
555 int av_frame_get_channels (const AVFrame *frame);
566 int8_t *av_frame_get_qp_table(AVFrame *f, int *stride, int *type);
572 
573 /**
574  * Get the name of a colorspace.
575  * @return a static string identifying the colorspace; can be NULL.
576  */
577 const char *av_get_colorspace_name(enum AVColorSpace val);
578 
579 /**
580  * Allocate an AVFrame and set its fields to default values. The resulting
581  * struct must be freed using av_frame_free().
582  *
583  * @return An AVFrame filled with default values or NULL on failure.
584  *
585  * @note this only allocates the AVFrame itself, not the data buffers. Those
586  * must be allocated through other means, e.g. with av_frame_get_buffer() or
587  * manually.
588  */
589 AVFrame *av_frame_alloc(void);
590 
591 /**
592  * Free the frame and any dynamically allocated objects in it,
593  * e.g. extended_data. If the frame is reference counted, it will be
594  * unreferenced first.
595  *
596  * @param frame frame to be freed. The pointer will be set to NULL.
597  */
598 void av_frame_free(AVFrame **frame);
599 
600 /**
601  * Set up a new reference to the data described by the source frame.
602  *
603  * Copy frame properties from src to dst and create a new reference for each
604  * AVBufferRef from src.
605  *
606  * If src is not reference counted, new buffers are allocated and the data is
607  * copied.
608  *
609  * @return 0 on success, a negative AVERROR on error
610  */
611 int av_frame_ref(AVFrame *dst, const AVFrame *src);
612 
613 /**
614  * Create a new frame that references the same data as src.
615  *
616  * This is a shortcut for av_frame_alloc()+av_frame_ref().
617  *
618  * @return newly created AVFrame on success, NULL on error.
619  */
621 
622 /**
623  * Unreference all the buffers referenced by frame and reset the frame fields.
624  */
626 
627 /**
628  * Move everythnig contained in src to dst and reset src.
629  */
630 void av_frame_move_ref(AVFrame *dst, AVFrame *src);
631 
632 /**
633  * Allocate new buffer(s) for audio or video data.
634  *
635  * The following fields must be set on frame before calling this function:
636  * - format (pixel format for video, sample format for audio)
637  * - width and height for video
638  * - nb_samples and channel_layout for audio
639  *
640  * This function will fill AVFrame.data and AVFrame.buf arrays and, if
641  * necessary, allocate and fill AVFrame.extended_data and AVFrame.extended_buf.
642  * For planar formats, one buffer will be allocated for each plane.
643  *
644  * @param frame frame in which to store the new buffers.
645  * @param align required buffer size alignment
646  *
647  * @return 0 on success, a negative AVERROR on error.
648  */
650 
651 /**
652  * Check if the frame data is writable.
653  *
654  * @return A positive value if the frame data is writable (which is true if and
655  * only if each of the underlying buffers has only one reference, namely the one
656  * stored in this frame). Return 0 otherwise.
657  *
658  * If 1 is returned the answer is valid until av_buffer_ref() is called on any
659  * of the underlying AVBufferRefs (e.g. through av_frame_ref() or directly).
660  *
661  * @see av_frame_make_writable(), av_buffer_is_writable()
662  */
664 
665 /**
666  * Ensure that the frame data is writable, avoiding data copy if possible.
667  *
668  * Do nothing if the frame is writable, allocate new buffers and copy the data
669  * if it is not.
670  *
671  * @return 0 on success, a negative AVERROR on error.
672  *
673  * @see av_frame_is_writable(), av_buffer_is_writable(),
674  * av_buffer_make_writable()
675  */
677 
678 /**
679  * Copy the frame data from src to dst.
680  *
681  * This function does not allocate anything, dst must be already initialized and
682  * allocated with the same parameters as src.
683  *
684  * This function only copies the frame data (i.e. the contents of the data /
685  * extended data arrays), not any other properties.
686  *
687  * @return >= 0 on success, a negative AVERROR on error.
688  */
689 int av_frame_copy(AVFrame *dst, const AVFrame *src);
690 
691 /**
692  * Copy only "metadata" fields from src to dst.
693  *
694  * Metadata for the purpose of this function are those fields that do not affect
695  * the data layout in the buffers. E.g. pts, sample rate (for audio) or sample
696  * aspect ratio (for video), but not width/height or channel layout.
697  * Side data is also copied.
698  */
699 int av_frame_copy_props(AVFrame *dst, const AVFrame *src);
700 
701 /**
702  * Get the buffer reference a given data plane is stored in.
703  *
704  * @param plane index of the data plane of interest in frame->extended_data.
705  *
706  * @return the buffer reference that contains the plane or NULL if the input
707  * frame is not valid.
708  */
710 
711 /**
712  * Add a new side data to a frame.
713  *
714  * @param frame a frame to which the side data should be added
715  * @param type type of the added side data
716  * @param size size of the side data
717  *
718  * @return newly added side data on success, NULL on error
719  */
722  int size);
723 
724 /**
725  * @return a pointer to the side data of a given type on success, NULL if there
726  * is no side data with such type in this frame.
727  */
730 
731 /**
732  * If side data of the supplied type exists in the frame, free it and remove it
733  * from the frame.
734  */
736 
737 /**
738  * @}
739  */
740 
741 #endif /* AVUTIL_FRAME_H */