ffmpeg/libavutil/frame.h
Soft Works daef8cbff7 avutil/frame: Document the possibility of negative line sizes
Signed-off-by: softworkz <softworkz@hotmail.com>
Signed-off-by: Marton Balint <cus@passwd.hu>
2021-11-18 20:40:24 +01:00

910 lines
30 KiB
C

/*
* 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
*/
/**
* @file
* @ingroup lavu_frame
* reference-counted frame API
*/
#ifndef AVUTIL_FRAME_H
#define AVUTIL_FRAME_H
#include <stddef.h>
#include <stdint.h>
#include "avutil.h"
#include "buffer.h"
#include "dict.h"
#include "rational.h"
#include "samplefmt.h"
#include "pixfmt.h"
#include "version.h"
/**
* @defgroup lavu_frame AVFrame
* @ingroup lavu_data
*
* @{
* AVFrame is an abstraction for reference-counted raw multimedia data.
*/
enum AVFrameSideDataType {
/**
* The data is the AVPanScan struct defined in libavcodec.
*/
AV_FRAME_DATA_PANSCAN,
/**
* ATSC A53 Part 4 Closed Captions.
* A53 CC bitstream is stored as uint8_t in AVFrameSideData.data.
* The number of bytes of CC data is AVFrameSideData.size.
*/
AV_FRAME_DATA_A53_CC,
/**
* Stereoscopic 3d metadata.
* The data is the AVStereo3D struct defined in libavutil/stereo3d.h.
*/
AV_FRAME_DATA_STEREO3D,
/**
* The data is the AVMatrixEncoding enum defined in libavutil/channel_layout.h.
*/
AV_FRAME_DATA_MATRIXENCODING,
/**
* Metadata relevant to a downmix procedure.
* The data is the AVDownmixInfo struct defined in libavutil/downmix_info.h.
*/
AV_FRAME_DATA_DOWNMIX_INFO,
/**
* ReplayGain information in the form of the AVReplayGain struct.
*/
AV_FRAME_DATA_REPLAYGAIN,
/**
* This side data contains a 3x3 transformation matrix describing an affine
* transformation that needs to be applied to the frame for correct
* presentation.
*
* See libavutil/display.h for a detailed description of the data.
*/
AV_FRAME_DATA_DISPLAYMATRIX,
/**
* Active Format Description data consisting of a single byte as specified
* in ETSI TS 101 154 using AVActiveFormatDescription enum.
*/
AV_FRAME_DATA_AFD,
/**
* Motion vectors exported by some codecs (on demand through the export_mvs
* flag set in the libavcodec AVCodecContext flags2 option).
* The data is the AVMotionVector struct defined in
* libavutil/motion_vector.h.
*/
AV_FRAME_DATA_MOTION_VECTORS,
/**
* Recommmends skipping the specified number of samples. This is exported
* only if the "skip_manual" AVOption is set in libavcodec.
* This has the same format as AV_PKT_DATA_SKIP_SAMPLES.
* @code
* u32le number of samples to skip from start of this packet
* u32le number of samples to skip from end of this packet
* u8 reason for start skip
* u8 reason for end skip (0=padding silence, 1=convergence)
* @endcode
*/
AV_FRAME_DATA_SKIP_SAMPLES,
/**
* This side data must be associated with an audio frame and corresponds to
* enum AVAudioServiceType defined in avcodec.h.
*/
AV_FRAME_DATA_AUDIO_SERVICE_TYPE,
/**
* Mastering display metadata associated with a video frame. The payload is
* an AVMasteringDisplayMetadata type and contains information about the
* mastering display color volume.
*/
AV_FRAME_DATA_MASTERING_DISPLAY_METADATA,
/**
* The GOP timecode in 25 bit timecode format. Data format is 64-bit integer.
* This is set on the first frame of a GOP that has a temporal reference of 0.
*/
AV_FRAME_DATA_GOP_TIMECODE,
/**
* The data represents the AVSphericalMapping structure defined in
* libavutil/spherical.h.
*/
AV_FRAME_DATA_SPHERICAL,
/**
* Content light level (based on CTA-861.3). This payload contains data in
* the form of the AVContentLightMetadata struct.
*/
AV_FRAME_DATA_CONTENT_LIGHT_LEVEL,
/**
* The data contains an ICC profile as an opaque octet buffer following the
* format described by ISO 15076-1 with an optional name defined in the
* metadata key entry "name".
*/
AV_FRAME_DATA_ICC_PROFILE,
/**
* Timecode which conforms to SMPTE ST 12-1. The data is an array of 4 uint32_t
* where the first uint32_t describes how many (1-3) of the other timecodes are used.
* The timecode format is described in the documentation of av_timecode_get_smpte_from_framenum()
* function in libavutil/timecode.h.
*/
AV_FRAME_DATA_S12M_TIMECODE,
/**
* HDR dynamic metadata associated with a video frame. The payload is
* an AVDynamicHDRPlus type and contains information for color
* volume transform - application 4 of SMPTE 2094-40:2016 standard.
*/
AV_FRAME_DATA_DYNAMIC_HDR_PLUS,
/**
* Regions Of Interest, the data is an array of AVRegionOfInterest type, the number of
* array element is implied by AVFrameSideData.size / AVRegionOfInterest.self_size.
*/
AV_FRAME_DATA_REGIONS_OF_INTEREST,
/**
* Encoding parameters for a video frame, as described by AVVideoEncParams.
*/
AV_FRAME_DATA_VIDEO_ENC_PARAMS,
/**
* User data unregistered metadata associated with a video frame.
* This is the H.26[45] UDU SEI message, and shouldn't be used for any other purpose
* The data is stored as uint8_t in AVFrameSideData.data which is 16 bytes of
* uuid_iso_iec_11578 followed by AVFrameSideData.size - 16 bytes of user_data_payload_byte.
*/
AV_FRAME_DATA_SEI_UNREGISTERED,
/**
* Film grain parameters for a frame, described by AVFilmGrainParams.
* Must be present for every frame which should have film grain applied.
*/
AV_FRAME_DATA_FILM_GRAIN_PARAMS,
/**
* Bounding boxes for object detection and classification,
* as described by AVDetectionBBoxHeader.
*/
AV_FRAME_DATA_DETECTION_BBOXES,
/**
* Dolby Vision RPU data, suitable for passing to x265
* or other libraries. Array of uint8_t, with NAL emulation
* bytes intact.
*/
AV_FRAME_DATA_DOVI_RPU_BUFFER,
};
enum AVActiveFormatDescription {
AV_AFD_SAME = 8,
AV_AFD_4_3 = 9,
AV_AFD_16_9 = 10,
AV_AFD_14_9 = 11,
AV_AFD_4_3_SP_14_9 = 13,
AV_AFD_16_9_SP_14_9 = 14,
AV_AFD_SP_4_3 = 15,
};
/**
* Structure to hold side data for an AVFrame.
*
* sizeof(AVFrameSideData) is not a part of the public ABI, so new fields may be added
* to the end with a minor bump.
*/
typedef struct AVFrameSideData {
enum AVFrameSideDataType type;
uint8_t *data;
size_t size;
AVDictionary *metadata;
AVBufferRef *buf;
} AVFrameSideData;
/**
* Structure describing a single Region Of Interest.
*
* When multiple regions are defined in a single side-data block, they
* should be ordered from most to least important - some encoders are only
* capable of supporting a limited number of distinct regions, so will have
* to truncate the list.
*
* When overlapping regions are defined, the first region containing a given
* area of the frame applies.
*/
typedef struct AVRegionOfInterest {
/**
* Must be set to the size of this data structure (that is,
* sizeof(AVRegionOfInterest)).
*/
uint32_t self_size;
/**
* Distance in pixels from the top edge of the frame to the top and
* bottom edges and from the left edge of the frame to the left and
* right edges of the rectangle defining this region of interest.
*
* The constraints on a region are encoder dependent, so the region
* actually affected may be slightly larger for alignment or other
* reasons.
*/
int top;
int bottom;
int left;
int right;
/**
* Quantisation offset.
*
* Must be in the range -1 to +1. A value of zero indicates no quality
* change. A negative value asks for better quality (less quantisation),
* while a positive value asks for worse quality (greater quantisation).
*
* The range is calibrated so that the extreme values indicate the
* largest possible offset - if the rest of the frame is encoded with the
* worst possible quality, an offset of -1 indicates that this region
* should be encoded with the best possible quality anyway. Intermediate
* values are then interpolated in some codec-dependent way.
*
* For example, in 10-bit H.264 the quantisation parameter varies between
* -12 and 51. A typical qoffset value of -1/10 therefore indicates that
* this region should be encoded with a QP around one-tenth of the full
* range better than the rest of the frame. So, if most of the frame
* were to be encoded with a QP of around 30, this region would get a QP
* of around 24 (an offset of approximately -1/10 * (51 - -12) = -6.3).
* An extreme value of -1 would indicate that this region should be
* encoded with the best possible quality regardless of the treatment of
* the rest of the frame - that is, should be encoded at a QP of -12.
*/
AVRational qoffset;
} AVRegionOfInterest;
/**
* This structure describes decoded (raw) audio or video data.
*
* AVFrame must be allocated using av_frame_alloc(). Note that this only
* allocates the AVFrame itself, the buffers for the data must be managed
* through other means (see below).
* AVFrame must be freed with av_frame_free().
*
* AVFrame is typically allocated once and then reused multiple times to hold
* different data (e.g. a single AVFrame to hold frames received from a
* decoder). In such a case, av_frame_unref() will free any references held by
* the frame and reset it to its original clean state before it
* is reused again.
*
* The data described by an AVFrame is usually reference counted through the
* AVBuffer API. The underlying buffer references are stored in AVFrame.buf /
* AVFrame.extended_buf. An AVFrame is considered to be reference counted if at
* least one reference is set, i.e. if AVFrame.buf[0] != NULL. In such a case,
* every single data plane must be contained in one of the buffers in
* AVFrame.buf or AVFrame.extended_buf.
* There may be a single buffer for all the data, or one separate buffer for
* each plane, or anything in between.
*
* sizeof(AVFrame) is not a part of the public ABI, so new fields may be added
* to the end with a minor bump.
*
* Fields can be accessed through AVOptions, the name string used, matches the
* C structure field name for fields accessible through AVOptions. The AVClass
* for AVFrame can be obtained from avcodec_get_frame_class()
*/
typedef struct AVFrame {
#define AV_NUM_DATA_POINTERS 8
/**
* pointer to the picture/channel planes.
* This might be different from the first allocated byte. For video,
* it could even point to the end of the image data.
*
* Some decoders access areas outside 0,0 - width,height, please
* see avcodec_align_dimensions2(). Some filters and swscale can read
* up to 16 bytes beyond the planes, if these filters are to be used,
* then 16 extra bytes must be allocated.
*
* NOTE: Except for hwaccel formats, pointers not needed by the format
* MUST be set to NULL.
*
* @attention In case of video, the data[] pointers can point to the
* end of image data in order to reverse line order, when used in
* combination with negative values in the linesize[] array.
*/
uint8_t *data[AV_NUM_DATA_POINTERS];
/**
* For video, a positive or negative value, which is typically indicating
* the size in bytes of each picture line, but it can also be:
* - the negative byte size of lines for vertical flipping
* (with data[n] pointing to the end of the data
* - a positive or negative multiple of the byte size as for accessing
* even and odd fields of a frame (possibly flipped)
*
* For audio, only linesize[0] may be set. For planar audio, each channel
* plane must be the same size.
*
* For video the linesizes should be multiples of the CPUs alignment
* preference, this is 16 or 32 for modern desktop CPUs.
* Some code requires such alignment other code can be slower without
* correct alignment, for yet other it makes no difference.
*
* @note The linesize may be larger than the size of usable data -- there
* may be extra padding present for performance reasons.
*
* @attention In case of video, line size values can be negative to achieve
* a vertically inverted iteration over image lines.
*/
int linesize[AV_NUM_DATA_POINTERS];
/**
* pointers to the data planes/channels.
*
* For video, this should simply point to data[].
*
* For planar audio, each channel has a separate data pointer, and
* linesize[0] contains the size of each channel buffer.
* For packed audio, there is just one data pointer, and linesize[0]
* contains the total size of the buffer for all channels.
*
* Note: Both data and extended_data should always be set in a valid frame,
* but for planar audio with more channels that can fit in data,
* extended_data must be used in order to access all channels.
*/
uint8_t **extended_data;
/**
* @name Video dimensions
* Video frames only. The coded dimensions (in pixels) of the video frame,
* i.e. the size of the rectangle that contains some well-defined values.
*
* @note The part of the frame intended for display/presentation is further
* restricted by the @ref cropping "Cropping rectangle".
* @{
*/
int width, height;
/**
* @}
*/
/**
* number of audio samples (per channel) described by this frame
*/
int nb_samples;
/**
* format of the frame, -1 if unknown or unset
* Values correspond to enum AVPixelFormat for video frames,
* enum AVSampleFormat for audio)
*/
int format;
/**
* 1 -> keyframe, 0-> not
*/
int key_frame;
/**
* Picture type of the frame.
*/
enum AVPictureType pict_type;
/**
* Sample aspect ratio for the video frame, 0/1 if unknown/unspecified.
*/
AVRational sample_aspect_ratio;
/**
* Presentation timestamp in time_base units (time when frame should be shown to user).
*/
int64_t pts;
/**
* DTS copied from the AVPacket that triggered returning this frame. (if frame threading isn't used)
* This is also the Presentation time of this AVFrame calculated from
* only AVPacket.dts values without pts values.
*/
int64_t pkt_dts;
/**
* picture number in bitstream order
*/
int coded_picture_number;
/**
* picture number in display order
*/
int display_picture_number;
/**
* quality (between 1 (good) and FF_LAMBDA_MAX (bad))
*/
int quality;
/**
* for some private data of the user
*/
void *opaque;
/**
* When decoding, this signals how much the picture must be delayed.
* extra_delay = repeat_pict / (2*fps)
*/
int repeat_pict;
/**
* The content of the picture is interlaced.
*/
int interlaced_frame;
/**
* If the content is interlaced, is top field displayed first.
*/
int top_field_first;
/**
* Tell user application that palette has changed from previous frame.
*/
int palette_has_changed;
/**
* reordered opaque 64 bits (generally an integer or a double precision float
* PTS but can be anything).
* The user sets AVCodecContext.reordered_opaque to represent the input at
* that time,
* the decoder reorders values as needed and sets AVFrame.reordered_opaque
* to exactly one of the values provided by the user through AVCodecContext.reordered_opaque
*/
int64_t reordered_opaque;
/**
* Sample rate of the audio data.
*/
int sample_rate;
/**
* Channel layout of the audio data.
*/
uint64_t channel_layout;
/**
* AVBuffer references backing the data for this frame. If all elements of
* this array are NULL, then this frame is not reference counted. This array
* must be filled contiguously -- if buf[i] is non-NULL then buf[j] must
* also be non-NULL for all j < i.
*
* There may be at most one AVBuffer per data plane, so for video this array
* always contains all the references. For planar audio with more than
* AV_NUM_DATA_POINTERS channels, there may be more buffers than can fit in
* this array. Then the extra AVBufferRef pointers are stored in the
* extended_buf array.
*/
AVBufferRef *buf[AV_NUM_DATA_POINTERS];
/**
* For planar audio which requires more than AV_NUM_DATA_POINTERS
* AVBufferRef pointers, this array will hold all the references which
* cannot fit into AVFrame.buf.
*
* Note that this is different from AVFrame.extended_data, which always
* contains all the pointers. This array only contains the extra pointers,
* which cannot fit into AVFrame.buf.
*
* This array is always allocated using av_malloc() by whoever constructs
* the frame. It is freed in av_frame_unref().
*/
AVBufferRef **extended_buf;
/**
* Number of elements in extended_buf.
*/
int nb_extended_buf;
AVFrameSideData **side_data;
int nb_side_data;
/**
* @defgroup lavu_frame_flags AV_FRAME_FLAGS
* @ingroup lavu_frame
* Flags describing additional frame properties.
*
* @{
*/
/**
* The frame data may be corrupted, e.g. due to decoding errors.
*/
#define AV_FRAME_FLAG_CORRUPT (1 << 0)
/**
* A flag to mark the frames which need to be decoded, but shouldn't be output.
*/
#define AV_FRAME_FLAG_DISCARD (1 << 2)
/**
* @}
*/
/**
* Frame flags, a combination of @ref lavu_frame_flags
*/
int flags;
/**
* MPEG vs JPEG YUV range.
* - encoding: Set by user
* - decoding: Set by libavcodec
*/
enum AVColorRange color_range;
enum AVColorPrimaries color_primaries;
enum AVColorTransferCharacteristic color_trc;
/**
* YUV colorspace type.
* - encoding: Set by user
* - decoding: Set by libavcodec
*/
enum AVColorSpace colorspace;
enum AVChromaLocation chroma_location;
/**
* frame timestamp estimated using various heuristics, in stream time base
* - encoding: unused
* - decoding: set by libavcodec, read by user.
*/
int64_t best_effort_timestamp;
/**
* reordered pos from the last AVPacket that has been input into the decoder
* - encoding: unused
* - decoding: Read by user.
*/
int64_t pkt_pos;
/**
* duration of the corresponding packet, expressed in
* AVStream->time_base units, 0 if unknown.
* - encoding: unused
* - decoding: Read by user.
*/
int64_t pkt_duration;
/**
* metadata.
* - encoding: Set by user.
* - decoding: Set by libavcodec.
*/
AVDictionary *metadata;
/**
* decode error flags of the frame, set to a combination of
* FF_DECODE_ERROR_xxx flags if the decoder produced a frame, but there
* were errors during the decoding.
* - encoding: unused
* - decoding: set by libavcodec, read by user.
*/
int decode_error_flags;
#define FF_DECODE_ERROR_INVALID_BITSTREAM 1
#define FF_DECODE_ERROR_MISSING_REFERENCE 2
#define FF_DECODE_ERROR_CONCEALMENT_ACTIVE 4
#define FF_DECODE_ERROR_DECODE_SLICES 8
/**
* number of audio channels, only used for audio.
* - encoding: unused
* - decoding: Read by user.
*/
int channels;
/**
* size of the corresponding packet containing the compressed
* frame.
* It is set to a negative value if unknown.
* - encoding: unused
* - decoding: set by libavcodec, read by user.
*/
int pkt_size;
/**
* For hwaccel-format frames, this should be a reference to the
* AVHWFramesContext describing the frame.
*/
AVBufferRef *hw_frames_ctx;
/**
* AVBufferRef for free use by the API user. FFmpeg will never check the
* contents of the buffer ref. FFmpeg calls av_buffer_unref() on it when
* the frame is unreferenced. av_frame_copy_props() calls create a new
* reference with av_buffer_ref() for the target frame's opaque_ref field.
*
* This is unrelated to the opaque field, although it serves a similar
* purpose.
*/
AVBufferRef *opaque_ref;
/**
* @anchor cropping
* @name Cropping
* Video frames only. The number of pixels to discard from the the
* top/bottom/left/right border of the frame to obtain the sub-rectangle of
* the frame intended for presentation.
* @{
*/
size_t crop_top;
size_t crop_bottom;
size_t crop_left;
size_t crop_right;
/**
* @}
*/
/**
* AVBufferRef for internal use by a single libav* library.
* Must not be used to transfer data between libraries.
* Has to be NULL when ownership of the frame leaves the respective library.
*
* Code outside the FFmpeg libs should never check or change the contents of the buffer ref.
*
* FFmpeg calls av_buffer_unref() on it when the frame is unreferenced.
* av_frame_copy_props() calls create a new reference with av_buffer_ref()
* for the target frame's private_ref field.
*/
AVBufferRef *private_ref;
} AVFrame;
#if FF_API_COLORSPACE_NAME
/**
* Get the name of a colorspace.
* @return a static string identifying the colorspace; can be NULL.
* @deprecated use av_color_space_name()
*/
attribute_deprecated
const char *av_get_colorspace_name(enum AVColorSpace val);
#endif
/**
* Allocate an AVFrame and set its fields to default values. The resulting
* struct must be freed using av_frame_free().
*
* @return An AVFrame filled with default values or NULL on failure.
*
* @note this only allocates the AVFrame itself, not the data buffers. Those
* must be allocated through other means, e.g. with av_frame_get_buffer() or
* manually.
*/
AVFrame *av_frame_alloc(void);
/**
* Free the frame and any dynamically allocated objects in it,
* e.g. extended_data. If the frame is reference counted, it will be
* unreferenced first.
*
* @param frame frame to be freed. The pointer will be set to NULL.
*/
void av_frame_free(AVFrame **frame);
/**
* Set up a new reference to the data described by the source frame.
*
* Copy frame properties from src to dst and create a new reference for each
* AVBufferRef from src.
*
* If src is not reference counted, new buffers are allocated and the data is
* copied.
*
* @warning: dst MUST have been either unreferenced with av_frame_unref(dst),
* or newly allocated with av_frame_alloc() before calling this
* function, or undefined behavior will occur.
*
* @return 0 on success, a negative AVERROR on error
*/
int av_frame_ref(AVFrame *dst, const AVFrame *src);
/**
* Create a new frame that references the same data as src.
*
* This is a shortcut for av_frame_alloc()+av_frame_ref().
*
* @return newly created AVFrame on success, NULL on error.
*/
AVFrame *av_frame_clone(const AVFrame *src);
/**
* Unreference all the buffers referenced by frame and reset the frame fields.
*/
void av_frame_unref(AVFrame *frame);
/**
* Move everything contained in src to dst and reset src.
*
* @warning: dst is not unreferenced, but directly overwritten without reading
* or deallocating its contents. Call av_frame_unref(dst) manually
* before calling this function to ensure that no memory is leaked.
*/
void av_frame_move_ref(AVFrame *dst, AVFrame *src);
/**
* Allocate new buffer(s) for audio or video data.
*
* The following fields must be set on frame before calling this function:
* - format (pixel format for video, sample format for audio)
* - width and height for video
* - nb_samples and channel_layout for audio
*
* This function will fill AVFrame.data and AVFrame.buf arrays and, if
* necessary, allocate and fill AVFrame.extended_data and AVFrame.extended_buf.
* For planar formats, one buffer will be allocated for each plane.
*
* @warning: if frame already has been allocated, calling this function will
* leak memory. In addition, undefined behavior can occur in certain
* cases.
*
* @param frame frame in which to store the new buffers.
* @param align Required buffer size alignment. If equal to 0, alignment will be
* chosen automatically for the current CPU. It is highly
* recommended to pass 0 here unless you know what you are doing.
*
* @return 0 on success, a negative AVERROR on error.
*/
int av_frame_get_buffer(AVFrame *frame, int align);
/**
* Check if the frame data is writable.
*
* @return A positive value if the frame data is writable (which is true if and
* only if each of the underlying buffers has only one reference, namely the one
* stored in this frame). Return 0 otherwise.
*
* If 1 is returned the answer is valid until av_buffer_ref() is called on any
* of the underlying AVBufferRefs (e.g. through av_frame_ref() or directly).
*
* @see av_frame_make_writable(), av_buffer_is_writable()
*/
int av_frame_is_writable(AVFrame *frame);
/**
* Ensure that the frame data is writable, avoiding data copy if possible.
*
* Do nothing if the frame is writable, allocate new buffers and copy the data
* if it is not.
*
* @return 0 on success, a negative AVERROR on error.
*
* @see av_frame_is_writable(), av_buffer_is_writable(),
* av_buffer_make_writable()
*/
int av_frame_make_writable(AVFrame *frame);
/**
* Copy the frame data from src to dst.
*
* This function does not allocate anything, dst must be already initialized and
* allocated with the same parameters as src.
*
* This function only copies the frame data (i.e. the contents of the data /
* extended data arrays), not any other properties.
*
* @return >= 0 on success, a negative AVERROR on error.
*/
int av_frame_copy(AVFrame *dst, const AVFrame *src);
/**
* Copy only "metadata" fields from src to dst.
*
* Metadata for the purpose of this function are those fields that do not affect
* the data layout in the buffers. E.g. pts, sample rate (for audio) or sample
* aspect ratio (for video), but not width/height or channel layout.
* Side data is also copied.
*/
int av_frame_copy_props(AVFrame *dst, const AVFrame *src);
/**
* Get the buffer reference a given data plane is stored in.
*
* @param plane index of the data plane of interest in frame->extended_data.
*
* @return the buffer reference that contains the plane or NULL if the input
* frame is not valid.
*/
AVBufferRef *av_frame_get_plane_buffer(AVFrame *frame, int plane);
/**
* Add a new side data to a frame.
*
* @param frame a frame to which the side data should be added
* @param type type of the added side data
* @param size size of the side data
*
* @return newly added side data on success, NULL on error
*/
AVFrameSideData *av_frame_new_side_data(AVFrame *frame,
enum AVFrameSideDataType type,
size_t size);
/**
* Add a new side data to a frame from an existing AVBufferRef
*
* @param frame a frame to which the side data should be added
* @param type the type of the added side data
* @param buf an AVBufferRef to add as side data. The ownership of
* the reference is transferred to the frame.
*
* @return newly added side data on success, NULL on error. On failure
* the frame is unchanged and the AVBufferRef remains owned by
* the caller.
*/
AVFrameSideData *av_frame_new_side_data_from_buf(AVFrame *frame,
enum AVFrameSideDataType type,
AVBufferRef *buf);
/**
* @return a pointer to the side data of a given type on success, NULL if there
* is no side data with such type in this frame.
*/
AVFrameSideData *av_frame_get_side_data(const AVFrame *frame,
enum AVFrameSideDataType type);
/**
* Remove and free all side data instances of the given type.
*/
void av_frame_remove_side_data(AVFrame *frame, enum AVFrameSideDataType type);
/**
* Flags for frame cropping.
*/
enum {
/**
* Apply the maximum possible cropping, even if it requires setting the
* AVFrame.data[] entries to unaligned pointers. Passing unaligned data
* to FFmpeg API is generally not allowed, and causes undefined behavior
* (such as crashes). You can pass unaligned data only to FFmpeg APIs that
* are explicitly documented to accept it. Use this flag only if you
* absolutely know what you are doing.
*/
AV_FRAME_CROP_UNALIGNED = 1 << 0,
};
/**
* Crop the given video AVFrame according to its crop_left/crop_top/crop_right/
* crop_bottom fields. If cropping is successful, the function will adjust the
* data pointers and the width/height fields, and set the crop fields to 0.
*
* In all cases, the cropping boundaries will be rounded to the inherent
* alignment of the pixel format. In some cases, such as for opaque hwaccel
* formats, the left/top cropping is ignored. The crop fields are set to 0 even
* if the cropping was rounded or ignored.
*
* @param frame the frame which should be cropped
* @param flags Some combination of AV_FRAME_CROP_* flags, or 0.
*
* @return >= 0 on success, a negative AVERROR on error. If the cropping fields
* were invalid, AVERROR(ERANGE) is returned, and nothing is changed.
*/
int av_frame_apply_cropping(AVFrame *frame, int flags);
/**
* @return a string identifying the side data type
*/
const char *av_frame_side_data_name(enum AVFrameSideDataType type);
/**
* @}
*/
#endif /* AVUTIL_FRAME_H */