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frame.h
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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 "pixfmt.h"
37 #include "version.h"
38 
39 
40 /**
41  * @defgroup lavu_frame AVFrame
42  * @ingroup lavu_data
43  *
44  * @{
45  * AVFrame is an abstraction for reference-counted raw multimedia data.
46  */
47 
49  /**
50  * The data is the AVPanScan struct defined in libavcodec.
51  */
53  /**
54  * ATSC A53 Part 4 Closed Captions.
55  * A53 CC bitstream is stored as uint8_t in AVFrameSideData.data.
56  * The number of bytes of CC data is AVFrameSideData.size.
57  */
59  /**
60  * Stereoscopic 3d metadata.
61  * The data is the AVStereo3D struct defined in libavutil/stereo3d.h.
62  */
64  /**
65  * The data is the AVMatrixEncoding enum defined in libavutil/channel_layout.h.
66  */
68  /**
69  * Metadata relevant to a downmix procedure.
70  * The data is the AVDownmixInfo struct defined in libavutil/downmix_info.h.
71  */
73  /**
74  * ReplayGain information in the form of the AVReplayGain struct.
75  */
77  /**
78  * This side data contains a 3x3 transformation matrix describing an affine
79  * transformation that needs to be applied to the frame for correct
80  * presentation.
81  *
82  * See libavutil/display.h for a detailed description of the data.
83  */
85  /**
86  * Active Format Description data consisting of a single byte as specified
87  * in ETSI TS 101 154 using AVActiveFormatDescription enum.
88  */
90  /**
91  * Motion vectors exported by some codecs (on demand through the export_mvs
92  * flag set in the libavcodec AVCodecContext flags2 option).
93  * The data is the AVMotionVector struct defined in
94  * libavutil/motion_vector.h.
95  */
97  /**
98  * Recommmends skipping the specified number of samples. This is exported
99  * only if the "skip_manual" AVOption is set in libavcodec.
100  * This has the same format as AV_PKT_DATA_SKIP_SAMPLES.
101  * @code
102  * u32le number of samples to skip from start of this packet
103  * u32le number of samples to skip from end of this packet
104  * u8 reason for start skip
105  * u8 reason for end skip (0=padding silence, 1=convergence)
106  * @endcode
107  */
109 
110  /**
111  * This side data must be associated with an audio frame and corresponds to
112  * enum AVAudioServiceType defined in avcodec.h.
113  */
115 };
116 
125 };
126 
127 typedef struct AVFrameSideData {
130  int size;
133 
134 /**
135  * This structure describes decoded (raw) audio or video data.
136  *
137  * AVFrame must be allocated using av_frame_alloc(). Note that this only
138  * allocates the AVFrame itself, the buffers for the data must be managed
139  * through other means (see below).
140  * AVFrame must be freed with av_frame_free().
141  *
142  * AVFrame is typically allocated once and then reused multiple times to hold
143  * different data (e.g. a single AVFrame to hold frames received from a
144  * decoder). In such a case, av_frame_unref() will free any references held by
145  * the frame and reset it to its original clean state before it
146  * is reused again.
147  *
148  * The data described by an AVFrame is usually reference counted through the
149  * AVBuffer API. The underlying buffer references are stored in AVFrame.buf /
150  * AVFrame.extended_buf. An AVFrame is considered to be reference counted if at
151  * least one reference is set, i.e. if AVFrame.buf[0] != NULL. In such a case,
152  * every single data plane must be contained in one of the buffers in
153  * AVFrame.buf or AVFrame.extended_buf.
154  * There may be a single buffer for all the data, or one separate buffer for
155  * each plane, or anything in between.
156  *
157  * sizeof(AVFrame) is not a part of the public ABI, so new fields may be added
158  * to the end with a minor bump.
159  * Similarly fields that are marked as to be only accessed by
160  * av_opt_ptr() can be reordered. This allows 2 forks to add fields
161  * without breaking compatibility with each other.
162  */
163 typedef struct AVFrame {
164 #define AV_NUM_DATA_POINTERS 8
165  /**
166  * pointer to the picture/channel planes.
167  * This might be different from the first allocated byte
168  *
169  * Some decoders access areas outside 0,0 - width,height, please
170  * see avcodec_align_dimensions2(). Some filters and swscale can read
171  * up to 16 bytes beyond the planes, if these filters are to be used,
172  * then 16 extra bytes must be allocated.
173  */
175 
176  /**
177  * For video, size in bytes of each picture line.
178  * For audio, size in bytes of each plane.
179  *
180  * For audio, only linesize[0] may be set. For planar audio, each channel
181  * plane must be the same size.
182  *
183  * For video the linesizes should be multiples of the CPUs alignment
184  * preference, this is 16 or 32 for modern desktop CPUs.
185  * Some code requires such alignment other code can be slower without
186  * correct alignment, for yet other it makes no difference.
187  *
188  * @note The linesize may be larger than the size of usable data -- there
189  * may be extra padding present for performance reasons.
190  */
192 
193  /**
194  * pointers to the data planes/channels.
195  *
196  * For video, this should simply point to data[].
197  *
198  * For planar audio, each channel has a separate data pointer, and
199  * linesize[0] contains the size of each channel buffer.
200  * For packed audio, there is just one data pointer, and linesize[0]
201  * contains the total size of the buffer for all channels.
202  *
203  * Note: Both data and extended_data should always be set in a valid frame,
204  * but for planar audio with more channels that can fit in data,
205  * extended_data must be used in order to access all channels.
206  */
208 
209  /**
210  * width and height of the video frame
211  */
212  int width, height;
213 
214  /**
215  * number of audio samples (per channel) described by this frame
216  */
218 
219  /**
220  * format of the frame, -1 if unknown or unset
221  * Values correspond to enum AVPixelFormat for video frames,
222  * enum AVSampleFormat for audio)
223  */
224  int format;
225 
226  /**
227  * 1 -> keyframe, 0-> not
228  */
230 
231  /**
232  * Picture type of the frame.
233  */
235 
236 #if FF_API_AVFRAME_LAVC
239 #endif
240 
241  /**
242  * Sample aspect ratio for the video frame, 0/1 if unknown/unspecified.
243  */
245 
246  /**
247  * Presentation timestamp in time_base units (time when frame should be shown to user).
248  */
249  int64_t pts;
250 
251  /**
252  * PTS copied from the AVPacket that was decoded to produce this frame.
253  */
254  int64_t pkt_pts;
255 
256  /**
257  * DTS copied from the AVPacket that triggered returning this frame. (if frame threading isn't used)
258  * This is also the Presentation time of this AVFrame calculated from
259  * only AVPacket.dts values without pts values.
260  */
261  int64_t pkt_dts;
262 
263  /**
264  * picture number in bitstream order
265  */
267  /**
268  * picture number in display order
269  */
271 
272  /**
273  * quality (between 1 (good) and FF_LAMBDA_MAX (bad))
274  */
275  int quality;
276 
277 #if FF_API_AVFRAME_LAVC
280 
281  /**
282  * QP table
283  */
285  int8_t *qscale_table;
286  /**
287  * QP store stride
288  */
290  int qstride;
291 
294 
295  /**
296  * mbskip_table[mb]>=1 if MB didn't change
297  * stride= mb_width = (width+15)>>4
298  */
301 
302  /**
303  * motion vector table
304  * @code
305  * example:
306  * int mv_sample_log2= 4 - motion_subsample_log2;
307  * int mb_width= (width+15)>>4;
308  * int mv_stride= (mb_width << mv_sample_log2) + 1;
309  * motion_val[direction][x + y*mv_stride][0->mv_x, 1->mv_y];
310  * @endcode
311  */
312  int16_t (*motion_val[2])[2];
313 
314  /**
315  * macroblock type table
316  * mb_type_base + mb_width + 2
317  */
319  uint32_t *mb_type;
320 
321  /**
322  * DCT coefficients
323  */
325  short *dct_coeff;
326 
327  /**
328  * motion reference frame index
329  * the order in which these are stored can depend on the codec.
330  */
332  int8_t *ref_index[2];
333 #endif
334 
335  /**
336  * for some private data of the user
337  */
338  void *opaque;
339 
340  /**
341  * error
342  */
344 
345 #if FF_API_AVFRAME_LAVC
347  int type;
348 #endif
349 
350  /**
351  * When decoding, this signals how much the picture must be delayed.
352  * extra_delay = repeat_pict / (2*fps)
353  */
355 
356  /**
357  * The content of the picture is interlaced.
358  */
360 
361  /**
362  * If the content is interlaced, is top field displayed first.
363  */
365 
366  /**
367  * Tell user application that palette has changed from previous frame.
368  */
370 
371 #if FF_API_AVFRAME_LAVC
374 
375  /**
376  * Pan scan.
377  */
380 #endif
381 
382  /**
383  * reordered opaque 64bit (generally an integer or a double precision float
384  * PTS but can be anything).
385  * The user sets AVCodecContext.reordered_opaque to represent the input at
386  * that time,
387  * the decoder reorders values as needed and sets AVFrame.reordered_opaque
388  * to exactly one of the values provided by the user through AVCodecContext.reordered_opaque
389  * @deprecated in favor of pkt_pts
390  */
392 
393 #if FF_API_AVFRAME_LAVC
394  /**
395  * @deprecated this field is unused
396  */
398 
403 
404  /**
405  * log2 of the size of the block which a single vector in motion_val represents:
406  * (4->16x16, 3->8x8, 2-> 4x4, 1-> 2x2)
407  */
409 #endif
410 
411  /**
412  * Sample rate of the audio data.
413  */
415 
416  /**
417  * Channel layout of the audio data.
418  */
419  uint64_t channel_layout;
420 
421  /**
422  * AVBuffer references backing the data for this frame. If all elements of
423  * this array are NULL, then this frame is not reference counted.
424  *
425  * There may be at most one AVBuffer per data plane, so for video this array
426  * always contains all the references. For planar audio with more than
427  * AV_NUM_DATA_POINTERS channels, there may be more buffers than can fit in
428  * this array. Then the extra AVBufferRef pointers are stored in the
429  * extended_buf array.
430  */
432 
433  /**
434  * For planar audio which requires more than AV_NUM_DATA_POINTERS
435  * AVBufferRef pointers, this array will hold all the references which
436  * cannot fit into AVFrame.buf.
437  *
438  * Note that this is different from AVFrame.extended_data, which always
439  * contains all the pointers. This array only contains the extra pointers,
440  * which cannot fit into AVFrame.buf.
441  *
442  * This array is always allocated using av_malloc() by whoever constructs
443  * the frame. It is freed in av_frame_unref().
444  */
446  /**
447  * Number of elements in extended_buf.
448  */
450 
453 
454 /**
455  * @defgroup lavu_frame_flags AV_FRAME_FLAGS
456  * Flags describing additional frame properties.
457  *
458  * @{
459  */
460 
461 /**
462  * The frame data may be corrupted, e.g. due to decoding errors.
463  */
464 #define AV_FRAME_FLAG_CORRUPT (1 << 0)
465 /**
466  * @}
467  */
468 
469  /**
470  * Frame flags, a combination of @ref lavu_frame_flags
471  */
472  int flags;
473 
474  /**
475  * MPEG vs JPEG YUV range.
476  * It must be accessed using av_frame_get_color_range() and
477  * av_frame_set_color_range().
478  * - encoding: Set by user
479  * - decoding: Set by libavcodec
480  */
482 
484 
486 
487  /**
488  * YUV colorspace type.
489  * It must be accessed using av_frame_get_colorspace() and
490  * av_frame_set_colorspace().
491  * - encoding: Set by user
492  * - decoding: Set by libavcodec
493  */
495 
497 
498  /**
499  * frame timestamp estimated using various heuristics, in stream time base
500  * Code outside libavcodec should access this field using:
501  * av_frame_get_best_effort_timestamp(frame)
502  * - encoding: unused
503  * - decoding: set by libavcodec, read by user.
504  */
506 
507  /**
508  * reordered pos from the last AVPacket that has been input into the decoder
509  * Code outside libavcodec should access this field using:
510  * av_frame_get_pkt_pos(frame)
511  * - encoding: unused
512  * - decoding: Read by user.
513  */
514  int64_t pkt_pos;
515 
516  /**
517  * duration of the corresponding packet, expressed in
518  * AVStream->time_base units, 0 if unknown.
519  * Code outside libavcodec should access this field using:
520  * av_frame_get_pkt_duration(frame)
521  * - encoding: unused
522  * - decoding: Read by user.
523  */
524  int64_t pkt_duration;
525 
526  /**
527  * metadata.
528  * Code outside libavcodec should access this field using:
529  * av_frame_get_metadata(frame)
530  * - encoding: Set by user.
531  * - decoding: Set by libavcodec.
532  */
534 
535  /**
536  * decode error flags of the frame, set to a combination of
537  * FF_DECODE_ERROR_xxx flags if the decoder produced a frame, but there
538  * were errors during the decoding.
539  * Code outside libavcodec should access this field using:
540  * av_frame_get_decode_error_flags(frame)
541  * - encoding: unused
542  * - decoding: set by libavcodec, read by user.
543  */
545 #define FF_DECODE_ERROR_INVALID_BITSTREAM 1
546 #define FF_DECODE_ERROR_MISSING_REFERENCE 2
547 
548  /**
549  * number of audio channels, only used for audio.
550  * Code outside libavcodec should access this field using:
551  * av_frame_get_channels(frame)
552  * - encoding: unused
553  * - decoding: Read by user.
554  */
555  int channels;
556 
557  /**
558  * size of the corresponding packet containing the compressed
559  * frame. It must be accessed using av_frame_get_pkt_size() and
560  * av_frame_set_pkt_size().
561  * It is set to a negative value if unknown.
562  * - encoding: unused
563  * - decoding: set by libavcodec, read by user.
564  */
565  int pkt_size;
566 
567  /**
568  * Not to be accessed directly from outside libavutil
569  */
571 } AVFrame;
572 
573 /**
574  * Accessors for some AVFrame fields.
575  * The position of these field in the structure is not part of the ABI,
576  * they should not be accessed directly outside libavcodec.
577  */
580 int64_t av_frame_get_pkt_duration (const AVFrame *frame);
581 void av_frame_set_pkt_duration (AVFrame *frame, int64_t val);
582 int64_t av_frame_get_pkt_pos (const AVFrame *frame);
583 void av_frame_set_pkt_pos (AVFrame *frame, int64_t val);
584 int64_t av_frame_get_channel_layout (const AVFrame *frame);
586 int av_frame_get_channels (const AVFrame *frame);
597 int8_t *av_frame_get_qp_table(AVFrame *f, int *stride, int *type);
603 
604 /**
605  * Get the name of a colorspace.
606  * @return a static string identifying the colorspace; can be NULL.
607  */
608 const char *av_get_colorspace_name(enum AVColorSpace val);
609 
610 /**
611  * Allocate an AVFrame and set its fields to default values. The resulting
612  * struct must be freed using av_frame_free().
613  *
614  * @return An AVFrame filled with default values or NULL on failure.
615  *
616  * @note this only allocates the AVFrame itself, not the data buffers. Those
617  * must be allocated through other means, e.g. with av_frame_get_buffer() or
618  * manually.
619  */
620 AVFrame *av_frame_alloc(void);
621 
622 /**
623  * Free the frame and any dynamically allocated objects in it,
624  * e.g. extended_data. If the frame is reference counted, it will be
625  * unreferenced first.
626  *
627  * @param frame frame to be freed. The pointer will be set to NULL.
628  */
629 void av_frame_free(AVFrame **frame);
630 
631 /**
632  * Set up a new reference to the data described by the source frame.
633  *
634  * Copy frame properties from src to dst and create a new reference for each
635  * AVBufferRef from src.
636  *
637  * If src is not reference counted, new buffers are allocated and the data is
638  * copied.
639  *
640  * @return 0 on success, a negative AVERROR on error
641  */
642 int av_frame_ref(AVFrame *dst, const AVFrame *src);
643 
644 /**
645  * Create a new frame that references the same data as src.
646  *
647  * This is a shortcut for av_frame_alloc()+av_frame_ref().
648  *
649  * @return newly created AVFrame on success, NULL on error.
650  */
652 
653 /**
654  * Unreference all the buffers referenced by frame and reset the frame fields.
655  */
657 
658 /**
659  * Move everythnig contained in src to dst and reset src.
660  */
661 void av_frame_move_ref(AVFrame *dst, AVFrame *src);
662 
663 /**
664  * Allocate new buffer(s) for audio or video data.
665  *
666  * The following fields must be set on frame before calling this function:
667  * - format (pixel format for video, sample format for audio)
668  * - width and height for video
669  * - nb_samples and channel_layout for audio
670  *
671  * This function will fill AVFrame.data and AVFrame.buf arrays and, if
672  * necessary, allocate and fill AVFrame.extended_data and AVFrame.extended_buf.
673  * For planar formats, one buffer will be allocated for each plane.
674  *
675  * @param frame frame in which to store the new buffers.
676  * @param align required buffer size alignment
677  *
678  * @return 0 on success, a negative AVERROR on error.
679  */
681 
682 /**
683  * Check if the frame data is writable.
684  *
685  * @return A positive value if the frame data is writable (which is true if and
686  * only if each of the underlying buffers has only one reference, namely the one
687  * stored in this frame). Return 0 otherwise.
688  *
689  * If 1 is returned the answer is valid until av_buffer_ref() is called on any
690  * of the underlying AVBufferRefs (e.g. through av_frame_ref() or directly).
691  *
692  * @see av_frame_make_writable(), av_buffer_is_writable()
693  */
695 
696 /**
697  * Ensure that the frame data is writable, avoiding data copy if possible.
698  *
699  * Do nothing if the frame is writable, allocate new buffers and copy the data
700  * if it is not.
701  *
702  * @return 0 on success, a negative AVERROR on error.
703  *
704  * @see av_frame_is_writable(), av_buffer_is_writable(),
705  * av_buffer_make_writable()
706  */
708 
709 /**
710  * Copy the frame data from src to dst.
711  *
712  * This function does not allocate anything, dst must be already initialized and
713  * allocated with the same parameters as src.
714  *
715  * This function only copies the frame data (i.e. the contents of the data /
716  * extended data arrays), not any other properties.
717  *
718  * @return >= 0 on success, a negative AVERROR on error.
719  */
720 int av_frame_copy(AVFrame *dst, const AVFrame *src);
721 
722 /**
723  * Copy only "metadata" fields from src to dst.
724  *
725  * Metadata for the purpose of this function are those fields that do not affect
726  * the data layout in the buffers. E.g. pts, sample rate (for audio) or sample
727  * aspect ratio (for video), but not width/height or channel layout.
728  * Side data is also copied.
729  */
730 int av_frame_copy_props(AVFrame *dst, const AVFrame *src);
731 
732 /**
733  * Get the buffer reference a given data plane is stored in.
734  *
735  * @param plane index of the data plane of interest in frame->extended_data.
736  *
737  * @return the buffer reference that contains the plane or NULL if the input
738  * frame is not valid.
739  */
741 
742 /**
743  * Add a new side data to a frame.
744  *
745  * @param frame a frame to which the side data should be added
746  * @param type type of the added side data
747  * @param size size of the side data
748  *
749  * @return newly added side data on success, NULL on error
750  */
753  int size);
754 
755 /**
756  * @return a pointer to the side data of a given type on success, NULL if there
757  * is no side data with such type in this frame.
758  */
761 
762 /**
763  * If side data of the supplied type exists in the frame, free it and remove it
764  * from the frame.
765  */
767 
768 /**
769  * @return a string identifying the side data type
770  */
772 
773 /**
774  * @}
775  */
776 
777 #endif /* AVUTIL_FRAME_H */