1 /* 2 * This file is part of FFmpeg. 3 * 4 * FFmpeg is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation; either 7 * version 2.1 of the License, or (at your option) any later version. 8 * 9 * FFmpeg is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Lesser General Public License for more details. 13 * 14 * You should have received a copy of the GNU Lesser General Public 15 * License along with FFmpeg; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 19 /** 20 * @file 21 * @ingroup lavu_frame 22 * reference-counted frame API 23 */ 24 25 #ifndef AVUTIL_FRAME_H 26 #define AVUTIL_FRAME_H 27 28 #include <stddef.h> 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 * @defgroup lavu_frame AVFrame 41 * @ingroup lavu_data 42 * 43 * @{ 44 * AVFrame is an abstraction for reference-counted raw multimedia data. 45 */ 46 47 enum AVFrameSideDataType { 48 /** 49 * The data is the AVPanScan struct defined in libavcodec. 50 */ 51 AV_FRAME_DATA_PANSCAN, 52 /** 53 * ATSC A53 Part 4 Closed Captions. 54 * A53 CC bitstream is stored as uint8_t in AVFrameSideData.data. 55 * The number of bytes of CC data is AVFrameSideData.size. 56 */ 57 AV_FRAME_DATA_A53_CC, 58 /** 59 * Stereoscopic 3d metadata. 60 * The data is the AVStereo3D struct defined in libavutil/stereo3d.h. 61 */ 62 AV_FRAME_DATA_STEREO3D, 63 /** 64 * The data is the AVMatrixEncoding enum defined in 65 * libavutil/channel_layout.h. 66 */ 67 AV_FRAME_DATA_MATRIXENCODING, 68 /** 69 * Metadata relevant to a downmix procedure. 70 * The data is the AVDownmixInfo struct defined in libavutil/downmix_info.h. 71 */ 72 AV_FRAME_DATA_DOWNMIX_INFO, 73 /** 74 * ReplayGain information in the form of the AVReplayGain struct. 75 */ 76 AV_FRAME_DATA_REPLAYGAIN, 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 */ 84 AV_FRAME_DATA_DISPLAYMATRIX, 85 /** 86 * Active Format Description data consisting of a single byte as specified 87 * in ETSI TS 101 154 using AVActiveFormatDescription enum. 88 */ 89 AV_FRAME_DATA_AFD, 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 */ 96 AV_FRAME_DATA_MOTION_VECTORS, 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 */ 108 AV_FRAME_DATA_SKIP_SAMPLES, 109 /** 110 * This side data must be associated with an audio frame and corresponds to 111 * enum AVAudioServiceType defined in avcodec.h. 112 */ 113 AV_FRAME_DATA_AUDIO_SERVICE_TYPE, 114 /** 115 * Mastering display metadata associated with a video frame. The payload is 116 * an AVMasteringDisplayMetadata type and contains information about the 117 * mastering display color volume. 118 */ 119 AV_FRAME_DATA_MASTERING_DISPLAY_METADATA, 120 /** 121 * The GOP timecode in 25 bit timecode format. Data format is 64-bit integer. 122 * This is set on the first frame of a GOP that has a temporal reference of 0. 123 */ 124 AV_FRAME_DATA_GOP_TIMECODE, 125 126 /** 127 * The data represents the AVSphericalMapping structure defined in 128 * libavutil/spherical.h. 129 */ 130 AV_FRAME_DATA_SPHERICAL, 131 132 /** 133 * Content light level (based on CTA-861.3). This payload contains data in 134 * the form of the AVContentLightMetadata struct. 135 */ 136 AV_FRAME_DATA_CONTENT_LIGHT_LEVEL, 137 138 /** 139 * The data contains an ICC profile as an opaque octet buffer following the 140 * format described by ISO 15076-1 with an optional name defined in the 141 * metadata key entry "name". 142 */ 143 AV_FRAME_DATA_ICC_PROFILE, 144 145 /** 146 * Timecode which conforms to SMPTE ST 12-1. The data is an array of 4 147 * uint32_t where the first uint32_t describes how many (1-3) of the other 148 * timecodes are used. The timecode format is described in the documentation 149 * of av_timecode_get_smpte_from_framenum() function in libavutil/timecode.h. 150 */ 151 AV_FRAME_DATA_S12M_TIMECODE, 152 153 /** 154 * HDR dynamic metadata associated with a video frame. The payload is 155 * an AVDynamicHDRPlus type and contains information for color 156 * volume transform - application 4 of SMPTE 2094-40:2016 standard. 157 */ 158 AV_FRAME_DATA_DYNAMIC_HDR_PLUS, 159 160 /** 161 * Regions Of Interest, the data is an array of AVRegionOfInterest type, the 162 * number of array element is implied by AVFrameSideData.size / 163 * AVRegionOfInterest.self_size. 164 */ 165 AV_FRAME_DATA_REGIONS_OF_INTEREST, 166 167 /** 168 * Encoding parameters for a video frame, as described by AVVideoEncParams. 169 */ 170 AV_FRAME_DATA_VIDEO_ENC_PARAMS, 171 172 /** 173 * User data unregistered metadata associated with a video frame. 174 * This is the H.26[45] UDU SEI message, and shouldn't be used for any other 175 * purpose The data is stored as uint8_t in AVFrameSideData.data which is 16 176 * bytes of uuid_iso_iec_11578 followed by AVFrameSideData.size - 16 bytes of 177 * user_data_payload_byte. 178 */ 179 AV_FRAME_DATA_SEI_UNREGISTERED, 180 181 /** 182 * Film grain parameters for a frame, described by AVFilmGrainParams. 183 * Must be present for every frame which should have film grain applied. 184 */ 185 AV_FRAME_DATA_FILM_GRAIN_PARAMS, 186 187 /** 188 * Bounding boxes for object detection and classification, 189 * as described by AVDetectionBBoxHeader. 190 */ 191 AV_FRAME_DATA_DETECTION_BBOXES, 192 193 /** 194 * Dolby Vision RPU raw data, suitable for passing to x265 195 * or other libraries. Array of uint8_t, with NAL emulation 196 * bytes intact. 197 */ 198 AV_FRAME_DATA_DOVI_RPU_BUFFER, 199 200 /** 201 * Parsed Dolby Vision metadata, suitable for passing to a software 202 * implementation. The payload is the AVDOVIMetadata struct defined in 203 * libavutil/dovi_meta.h. 204 */ 205 AV_FRAME_DATA_DOVI_METADATA, 206 }; 207 208 enum AVActiveFormatDescription { 209 AV_AFD_SAME = 8, 210 AV_AFD_4_3 = 9, 211 AV_AFD_16_9 = 10, 212 AV_AFD_14_9 = 11, 213 AV_AFD_4_3_SP_14_9 = 13, 214 AV_AFD_16_9_SP_14_9 = 14, 215 AV_AFD_SP_4_3 = 15, 216 }; 217 218 /** 219 * Structure to hold side data for an AVFrame. 220 * 221 * sizeof(AVFrameSideData) is not a part of the public ABI, so new fields may be 222 * added to the end with a minor bump. 223 */ 224 typedef struct AVFrameSideData { 225 enum AVFrameSideDataType type; 226 uint8_t* data; 227 size_t size; 228 AVDictionary* metadata; 229 AVBufferRef* buf; 230 } AVFrameSideData; 231 232 /** 233 * Structure describing a single Region Of Interest. 234 * 235 * When multiple regions are defined in a single side-data block, they 236 * should be ordered from most to least important - some encoders are only 237 * capable of supporting a limited number of distinct regions, so will have 238 * to truncate the list. 239 * 240 * When overlapping regions are defined, the first region containing a given 241 * area of the frame applies. 242 */ 243 typedef struct AVRegionOfInterest { 244 /** 245 * Must be set to the size of this data structure (that is, 246 * sizeof(AVRegionOfInterest)). 247 */ 248 uint32_t self_size; 249 /** 250 * Distance in pixels from the top edge of the frame to the top and 251 * bottom edges and from the left edge of the frame to the left and 252 * right edges of the rectangle defining this region of interest. 253 * 254 * The constraints on a region are encoder dependent, so the region 255 * actually affected may be slightly larger for alignment or other 256 * reasons. 257 */ 258 int top; 259 int bottom; 260 int left; 261 int right; 262 /** 263 * Quantisation offset. 264 * 265 * Must be in the range -1 to +1. A value of zero indicates no quality 266 * change. A negative value asks for better quality (less quantisation), 267 * while a positive value asks for worse quality (greater quantisation). 268 * 269 * The range is calibrated so that the extreme values indicate the 270 * largest possible offset - if the rest of the frame is encoded with the 271 * worst possible quality, an offset of -1 indicates that this region 272 * should be encoded with the best possible quality anyway. Intermediate 273 * values are then interpolated in some codec-dependent way. 274 * 275 * For example, in 10-bit H.264 the quantisation parameter varies between 276 * -12 and 51. A typical qoffset value of -1/10 therefore indicates that 277 * this region should be encoded with a QP around one-tenth of the full 278 * range better than the rest of the frame. So, if most of the frame 279 * were to be encoded with a QP of around 30, this region would get a QP 280 * of around 24 (an offset of approximately -1/10 * (51 - -12) = -6.3). 281 * An extreme value of -1 would indicate that this region should be 282 * encoded with the best possible quality regardless of the treatment of 283 * the rest of the frame - that is, should be encoded at a QP of -12. 284 */ 285 AVRational qoffset; 286 } AVRegionOfInterest; 287 288 /** 289 * This structure describes decoded (raw) audio or video data. 290 * 291 * AVFrame must be allocated using av_frame_alloc(). Note that this only 292 * allocates the AVFrame itself, the buffers for the data must be managed 293 * through other means (see below). 294 * AVFrame must be freed with av_frame_free(). 295 * 296 * AVFrame is typically allocated once and then reused multiple times to hold 297 * different data (e.g. a single AVFrame to hold frames received from a 298 * decoder). In such a case, av_frame_unref() will free any references held by 299 * the frame and reset it to its original clean state before it 300 * is reused again. 301 * 302 * The data described by an AVFrame is usually reference counted through the 303 * AVBuffer API. The underlying buffer references are stored in AVFrame.buf / 304 * AVFrame.extended_buf. An AVFrame is considered to be reference counted if at 305 * least one reference is set, i.e. if AVFrame.buf[0] != NULL. In such a case, 306 * every single data plane must be contained in one of the buffers in 307 * AVFrame.buf or AVFrame.extended_buf. 308 * There may be a single buffer for all the data, or one separate buffer for 309 * each plane, or anything in between. 310 * 311 * sizeof(AVFrame) is not a part of the public ABI, so new fields may be added 312 * to the end with a minor bump. 313 * 314 * Fields can be accessed through AVOptions, the name string used, matches the 315 * C structure field name for fields accessible through AVOptions. The AVClass 316 * for AVFrame can be obtained from avcodec_get_frame_class() 317 */ 318 typedef struct AVFrame { 319 #define AV_NUM_DATA_POINTERS 8 320 /** 321 * pointer to the picture/channel planes. 322 * This might be different from the first allocated byte. For video, 323 * it could even point to the end of the image data. 324 * 325 * All pointers in data and extended_data must point into one of the 326 * AVBufferRef in buf or extended_buf. 327 * 328 * Some decoders access areas outside 0,0 - width,height, please 329 * see avcodec_align_dimensions2(). Some filters and swscale can read 330 * up to 16 bytes beyond the planes, if these filters are to be used, 331 * then 16 extra bytes must be allocated. 332 * 333 * NOTE: Pointers not needed by the format MUST be set to NULL. 334 * 335 * @attention In case of video, the data[] pointers can point to the 336 * end of image data in order to reverse line order, when used in 337 * combination with negative values in the linesize[] array. 338 */ 339 uint8_t* data[AV_NUM_DATA_POINTERS]; 340 341 /** 342 * For video, a positive or negative value, which is typically indicating 343 * the size in bytes of each picture line, but it can also be: 344 * - the negative byte size of lines for vertical flipping 345 * (with data[n] pointing to the end of the data 346 * - a positive or negative multiple of the byte size as for accessing 347 * even and odd fields of a frame (possibly flipped) 348 * 349 * For audio, only linesize[0] may be set. For planar audio, each channel 350 * plane must be the same size. 351 * 352 * For video the linesizes should be multiples of the CPUs alignment 353 * preference, this is 16 or 32 for modern desktop CPUs. 354 * Some code requires such alignment other code can be slower without 355 * correct alignment, for yet other it makes no difference. 356 * 357 * @note The linesize may be larger than the size of usable data -- there 358 * may be extra padding present for performance reasons. 359 * 360 * @attention In case of video, line size values can be negative to achieve 361 * a vertically inverted iteration over image lines. 362 */ 363 int linesize[AV_NUM_DATA_POINTERS]; 364 365 /** 366 * pointers to the data planes/channels. 367 * 368 * For video, this should simply point to data[]. 369 * 370 * For planar audio, each channel has a separate data pointer, and 371 * linesize[0] contains the size of each channel buffer. 372 * For packed audio, there is just one data pointer, and linesize[0] 373 * contains the total size of the buffer for all channels. 374 * 375 * Note: Both data and extended_data should always be set in a valid frame, 376 * but for planar audio with more channels that can fit in data, 377 * extended_data must be used in order to access all channels. 378 */ 379 uint8_t** extended_data; 380 381 /** 382 * @name Video dimensions 383 * Video frames only. The coded dimensions (in pixels) of the video frame, 384 * i.e. the size of the rectangle that contains some well-defined values. 385 * 386 * @note The part of the frame intended for display/presentation is further 387 * restricted by the @ref cropping "Cropping rectangle". 388 * @{ 389 */ 390 int width, height; 391 /** 392 * @} 393 */ 394 395 /** 396 * number of audio samples (per channel) described by this frame 397 */ 398 int nb_samples; 399 400 /** 401 * format of the frame, -1 if unknown or unset 402 * Values correspond to enum AVPixelFormat for video frames, 403 * enum AVSampleFormat for audio) 404 */ 405 int format; 406 407 /** 408 * 1 -> keyframe, 0-> not 409 */ 410 int key_frame; 411 412 /** 413 * Picture type of the frame. 414 */ 415 enum AVPictureType pict_type; 416 417 /** 418 * Sample aspect ratio for the video frame, 0/1 if unknown/unspecified. 419 */ 420 AVRational sample_aspect_ratio; 421 422 /** 423 * Presentation timestamp in time_base units (time when frame should be shown 424 * to user). 425 */ 426 int64_t pts; 427 428 /** 429 * DTS copied from the AVPacket that triggered returning this frame. (if frame 430 * threading isn't used) This is also the Presentation time of this AVFrame 431 * calculated from only AVPacket.dts values without pts values. 432 */ 433 int64_t pkt_dts; 434 435 /** 436 * Time base for the timestamps in this frame. 437 * In the future, this field may be set on frames output by decoders or 438 * filters, but its value will be by default ignored on input to encoders 439 * or filters. 440 */ 441 AVRational time_base; 442 443 /** 444 * picture number in bitstream order 445 */ 446 int coded_picture_number; 447 /** 448 * picture number in display order 449 */ 450 int display_picture_number; 451 452 /** 453 * quality (between 1 (good) and FF_LAMBDA_MAX (bad)) 454 */ 455 int quality; 456 457 /** 458 * for some private data of the user 459 */ 460 void* opaque; 461 462 /** 463 * When decoding, this signals how much the picture must be delayed. 464 * extra_delay = repeat_pict / (2*fps) 465 */ 466 int repeat_pict; 467 468 /** 469 * The content of the picture is interlaced. 470 */ 471 int interlaced_frame; 472 473 /** 474 * If the content is interlaced, is top field displayed first. 475 */ 476 int top_field_first; 477 478 /** 479 * Tell user application that palette has changed from previous frame. 480 */ 481 int palette_has_changed; 482 483 /** 484 * reordered opaque 64 bits (generally an integer or a double precision float 485 * PTS but can be anything). 486 * The user sets AVCodecContext.reordered_opaque to represent the input at 487 * that time, 488 * the decoder reorders values as needed and sets AVFrame.reordered_opaque 489 * to exactly one of the values provided by the user through 490 * AVCodecContext.reordered_opaque 491 */ 492 int64_t reordered_opaque; 493 494 /** 495 * Sample rate of the audio data. 496 */ 497 int sample_rate; 498 499 /** 500 * Channel layout of the audio data. 501 */ 502 uint64_t channel_layout; 503 504 /** 505 * AVBuffer references backing the data for this frame. All the pointers in 506 * data and extended_data must point inside one of the buffers in buf or 507 * extended_buf. This array must be filled contiguously -- if buf[i] is 508 * non-NULL then buf[j] must also be non-NULL for all j < i. 509 * 510 * There may be at most one AVBuffer per data plane, so for video this array 511 * always contains all the references. For planar audio with more than 512 * AV_NUM_DATA_POINTERS channels, there may be more buffers than can fit in 513 * this array. Then the extra AVBufferRef pointers are stored in the 514 * extended_buf array. 515 */ 516 AVBufferRef* buf[AV_NUM_DATA_POINTERS]; 517 518 /** 519 * For planar audio which requires more than AV_NUM_DATA_POINTERS 520 * AVBufferRef pointers, this array will hold all the references which 521 * cannot fit into AVFrame.buf. 522 * 523 * Note that this is different from AVFrame.extended_data, which always 524 * contains all the pointers. This array only contains the extra pointers, 525 * which cannot fit into AVFrame.buf. 526 * 527 * This array is always allocated using av_malloc() by whoever constructs 528 * the frame. It is freed in av_frame_unref(). 529 */ 530 AVBufferRef** extended_buf; 531 /** 532 * Number of elements in extended_buf. 533 */ 534 int nb_extended_buf; 535 536 AVFrameSideData** side_data; 537 int nb_side_data; 538 539 /** 540 * @defgroup lavu_frame_flags AV_FRAME_FLAGS 541 * @ingroup lavu_frame 542 * Flags describing additional frame properties. 543 * 544 * @{ 545 */ 546 547 /** 548 * The frame data may be corrupted, e.g. due to decoding errors. 549 */ 550 #define AV_FRAME_FLAG_CORRUPT (1 << 0) 551 /** 552 * A flag to mark the frames which need to be decoded, but shouldn't be output. 553 */ 554 #define AV_FRAME_FLAG_DISCARD (1 << 2) 555 /** 556 * @} 557 */ 558 559 /** 560 * Frame flags, a combination of @ref lavu_frame_flags 561 */ 562 int flags; 563 564 /** 565 * MPEG vs JPEG YUV range. 566 * - encoding: Set by user 567 * - decoding: Set by libavcodec 568 */ 569 enum AVColorRange color_range; 570 571 enum AVColorPrimaries color_primaries; 572 573 enum AVColorTransferCharacteristic color_trc; 574 575 /** 576 * YUV colorspace type. 577 * - encoding: Set by user 578 * - decoding: Set by libavcodec 579 */ 580 enum AVColorSpace colorspace; 581 582 enum AVChromaLocation chroma_location; 583 584 /** 585 * frame timestamp estimated using various heuristics, in stream time base 586 * - encoding: unused 587 * - decoding: set by libavcodec, read by user. 588 */ 589 int64_t best_effort_timestamp; 590 591 /** 592 * reordered pos from the last AVPacket that has been input into the decoder 593 * - encoding: unused 594 * - decoding: Read by user. 595 */ 596 int64_t pkt_pos; 597 598 /** 599 * duration of the corresponding packet, expressed in 600 * AVStream->time_base units, 0 if unknown. 601 * - encoding: unused 602 * - decoding: Read by user. 603 */ 604 int64_t pkt_duration; 605 606 /** 607 * metadata. 608 * - encoding: Set by user. 609 * - decoding: Set by libavcodec. 610 */ 611 AVDictionary* metadata; 612 613 /** 614 * decode error flags of the frame, set to a combination of 615 * FF_DECODE_ERROR_xxx flags if the decoder produced a frame, but there 616 * were errors during the decoding. 617 * - encoding: unused 618 * - decoding: set by libavcodec, read by user. 619 */ 620 int decode_error_flags; 621 #define FF_DECODE_ERROR_INVALID_BITSTREAM 1 622 #define FF_DECODE_ERROR_MISSING_REFERENCE 2 623 #define FF_DECODE_ERROR_CONCEALMENT_ACTIVE 4 624 #define FF_DECODE_ERROR_DECODE_SLICES 8 625 626 /** 627 * number of audio channels, only used for audio. 628 * - encoding: unused 629 * - decoding: Read by user. 630 */ 631 int channels; 632 633 /** 634 * size of the corresponding packet containing the compressed 635 * frame. 636 * It is set to a negative value if unknown. 637 * - encoding: unused 638 * - decoding: set by libavcodec, read by user. 639 */ 640 int pkt_size; 641 642 /** 643 * For hwaccel-format frames, this should be a reference to the 644 * AVHWFramesContext describing the frame. 645 */ 646 AVBufferRef* hw_frames_ctx; 647 648 /** 649 * AVBufferRef for free use by the API user. FFmpeg will never check the 650 * contents of the buffer ref. FFmpeg calls av_buffer_unref() on it when 651 * the frame is unreferenced. av_frame_copy_props() calls create a new 652 * reference with av_buffer_ref() for the target frame's opaque_ref field. 653 * 654 * This is unrelated to the opaque field, although it serves a similar 655 * purpose. 656 */ 657 AVBufferRef* opaque_ref; 658 659 /** 660 * @anchor cropping 661 * @name Cropping 662 * Video frames only. The number of pixels to discard from the the 663 * top/bottom/left/right border of the frame to obtain the sub-rectangle of 664 * the frame intended for presentation. 665 * @{ 666 */ 667 size_t crop_top; 668 size_t crop_bottom; 669 size_t crop_left; 670 size_t crop_right; 671 /** 672 * @} 673 */ 674 675 /** 676 * AVBufferRef for internal use by a single libav* library. 677 * Must not be used to transfer data between libraries. 678 * Has to be NULL when ownership of the frame leaves the respective library. 679 * 680 * Code outside the FFmpeg libs should never check or change the contents of 681 * the buffer ref. 682 * 683 * FFmpeg calls av_buffer_unref() on it when the frame is unreferenced. 684 * av_frame_copy_props() calls create a new reference with av_buffer_ref() 685 * for the target frame's private_ref field. 686 */ 687 AVBufferRef* private_ref; 688 } AVFrame; 689 690 #if FF_API_COLORSPACE_NAME 691 /** 692 * Get the name of a colorspace. 693 * @return a static string identifying the colorspace; can be NULL. 694 * @deprecated use av_color_space_name() 695 */ 696 attribute_deprecated const char* av_get_colorspace_name(enum AVColorSpace val); 697 #endif 698 /** 699 * Allocate an AVFrame and set its fields to default values. The resulting 700 * struct must be freed using av_frame_free(). 701 * 702 * @return An AVFrame filled with default values or NULL on failure. 703 * 704 * @note this only allocates the AVFrame itself, not the data buffers. Those 705 * must be allocated through other means, e.g. with av_frame_get_buffer() or 706 * manually. 707 */ 708 AVFrame* av_frame_alloc(void); 709 710 /** 711 * Free the frame and any dynamically allocated objects in it, 712 * e.g. extended_data. If the frame is reference counted, it will be 713 * unreferenced first. 714 * 715 * @param frame frame to be freed. The pointer will be set to NULL. 716 */ 717 void av_frame_free(AVFrame** frame); 718 719 /** 720 * Set up a new reference to the data described by the source frame. 721 * 722 * Copy frame properties from src to dst and create a new reference for each 723 * AVBufferRef from src. 724 * 725 * If src is not reference counted, new buffers are allocated and the data is 726 * copied. 727 * 728 * @warning: dst MUST have been either unreferenced with av_frame_unref(dst), 729 * or newly allocated with av_frame_alloc() before calling this 730 * function, or undefined behavior will occur. 731 * 732 * @return 0 on success, a negative AVERROR on error 733 */ 734 int av_frame_ref(AVFrame* dst, const AVFrame* src); 735 736 /** 737 * Create a new frame that references the same data as src. 738 * 739 * This is a shortcut for av_frame_alloc()+av_frame_ref(). 740 * 741 * @return newly created AVFrame on success, NULL on error. 742 */ 743 AVFrame* av_frame_clone(const AVFrame* src); 744 745 /** 746 * Unreference all the buffers referenced by frame and reset the frame fields. 747 */ 748 void av_frame_unref(AVFrame* frame); 749 750 /** 751 * Move everything contained in src to dst and reset src. 752 * 753 * @warning: dst is not unreferenced, but directly overwritten without reading 754 * or deallocating its contents. Call av_frame_unref(dst) manually 755 * before calling this function to ensure that no memory is leaked. 756 */ 757 void av_frame_move_ref(AVFrame* dst, AVFrame* src); 758 759 /** 760 * Allocate new buffer(s) for audio or video data. 761 * 762 * The following fields must be set on frame before calling this function: 763 * - format (pixel format for video, sample format for audio) 764 * - width and height for video 765 * - nb_samples and channel_layout for audio 766 * 767 * This function will fill AVFrame.data and AVFrame.buf arrays and, if 768 * necessary, allocate and fill AVFrame.extended_data and AVFrame.extended_buf. 769 * For planar formats, one buffer will be allocated for each plane. 770 * 771 * @warning: if frame already has been allocated, calling this function will 772 * leak memory. In addition, undefined behavior can occur in certain 773 * cases. 774 * 775 * @param frame frame in which to store the new buffers. 776 * @param align Required buffer size alignment. If equal to 0, alignment will be 777 * chosen automatically for the current CPU. It is highly 778 * recommended to pass 0 here unless you know what you are doing. 779 * 780 * @return 0 on success, a negative AVERROR on error. 781 */ 782 int av_frame_get_buffer(AVFrame* frame, int align); 783 784 /** 785 * Check if the frame data is writable. 786 * 787 * @return A positive value if the frame data is writable (which is true if and 788 * only if each of the underlying buffers has only one reference, namely the one 789 * stored in this frame). Return 0 otherwise. 790 * 791 * If 1 is returned the answer is valid until av_buffer_ref() is called on any 792 * of the underlying AVBufferRefs (e.g. through av_frame_ref() or directly). 793 * 794 * @see av_frame_make_writable(), av_buffer_is_writable() 795 */ 796 int av_frame_is_writable(AVFrame* frame); 797 798 /** 799 * Ensure that the frame data is writable, avoiding data copy if possible. 800 * 801 * Do nothing if the frame is writable, allocate new buffers and copy the data 802 * if it is not. 803 * 804 * @return 0 on success, a negative AVERROR on error. 805 * 806 * @see av_frame_is_writable(), av_buffer_is_writable(), 807 * av_buffer_make_writable() 808 */ 809 int av_frame_make_writable(AVFrame* frame); 810 811 /** 812 * Copy the frame data from src to dst. 813 * 814 * This function does not allocate anything, dst must be already initialized and 815 * allocated with the same parameters as src. 816 * 817 * This function only copies the frame data (i.e. the contents of the data / 818 * extended data arrays), not any other properties. 819 * 820 * @return >= 0 on success, a negative AVERROR on error. 821 */ 822 int av_frame_copy(AVFrame* dst, const AVFrame* src); 823 824 /** 825 * Copy only "metadata" fields from src to dst. 826 * 827 * Metadata for the purpose of this function are those fields that do not affect 828 * the data layout in the buffers. E.g. pts, sample rate (for audio) or sample 829 * aspect ratio (for video), but not width/height or channel layout. 830 * Side data is also copied. 831 */ 832 int av_frame_copy_props(AVFrame* dst, const AVFrame* src); 833 834 /** 835 * Get the buffer reference a given data plane is stored in. 836 * 837 * @param plane index of the data plane of interest in frame->extended_data. 838 * 839 * @return the buffer reference that contains the plane or NULL if the input 840 * frame is not valid. 841 */ 842 AVBufferRef* av_frame_get_plane_buffer(AVFrame* frame, int plane); 843 844 /** 845 * Add a new side data to a frame. 846 * 847 * @param frame a frame to which the side data should be added 848 * @param type type of the added side data 849 * @param size size of the side data 850 * 851 * @return newly added side data on success, NULL on error 852 */ 853 AVFrameSideData* av_frame_new_side_data(AVFrame* frame, 854 enum AVFrameSideDataType type, 855 size_t size); 856 857 /** 858 * Add a new side data to a frame from an existing AVBufferRef 859 * 860 * @param frame a frame to which the side data should be added 861 * @param type the type of the added side data 862 * @param buf an AVBufferRef to add as side data. The ownership of 863 * the reference is transferred to the frame. 864 * 865 * @return newly added side data on success, NULL on error. On failure 866 * the frame is unchanged and the AVBufferRef remains owned by 867 * the caller. 868 */ 869 AVFrameSideData* av_frame_new_side_data_from_buf(AVFrame* frame, 870 enum AVFrameSideDataType type, 871 AVBufferRef* buf); 872 873 /** 874 * @return a pointer to the side data of a given type on success, NULL if there 875 * is no side data with such type in this frame. 876 */ 877 AVFrameSideData* av_frame_get_side_data(const AVFrame* frame, 878 enum AVFrameSideDataType type); 879 880 /** 881 * Remove and free all side data instances of the given type. 882 */ 883 void av_frame_remove_side_data(AVFrame* frame, enum AVFrameSideDataType type); 884 885 /** 886 * Flags for frame cropping. 887 */ 888 enum { 889 /** 890 * Apply the maximum possible cropping, even if it requires setting the 891 * AVFrame.data[] entries to unaligned pointers. Passing unaligned data 892 * to FFmpeg API is generally not allowed, and causes undefined behavior 893 * (such as crashes). You can pass unaligned data only to FFmpeg APIs that 894 * are explicitly documented to accept it. Use this flag only if you 895 * absolutely know what you are doing. 896 */ 897 AV_FRAME_CROP_UNALIGNED = 1 << 0, 898 }; 899 900 /** 901 * Crop the given video AVFrame according to its crop_left/crop_top/crop_right/ 902 * crop_bottom fields. If cropping is successful, the function will adjust the 903 * data pointers and the width/height fields, and set the crop fields to 0. 904 * 905 * In all cases, the cropping boundaries will be rounded to the inherent 906 * alignment of the pixel format. In some cases, such as for opaque hwaccel 907 * formats, the left/top cropping is ignored. The crop fields are set to 0 even 908 * if the cropping was rounded or ignored. 909 * 910 * @param frame the frame which should be cropped 911 * @param flags Some combination of AV_FRAME_CROP_* flags, or 0. 912 * 913 * @return >= 0 on success, a negative AVERROR on error. If the cropping fields 914 * were invalid, AVERROR(ERANGE) is returned, and nothing is changed. 915 */ 916 int av_frame_apply_cropping(AVFrame* frame, int flags); 917 918 /** 919 * @return a string identifying the side data type 920 */ 921 const char* av_frame_side_data_name(enum AVFrameSideDataType type); 922 923 /** 924 * @} 925 */ 926 927 #endif /* AVUTIL_FRAME_H */ 928