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AVPicture types, pixel formats and basic image planes manipulation. More...

Enumerations

enum  AVPictureType {
  AV_PICTURE_TYPE_NONE = 0, AV_PICTURE_TYPE_I, AV_PICTURE_TYPE_P, AV_PICTURE_TYPE_B,
  AV_PICTURE_TYPE_S, AV_PICTURE_TYPE_SI, AV_PICTURE_TYPE_SP, AV_PICTURE_TYPE_BI
}
 

Functions

char av_get_picture_type_char (enum AVPictureType pict_type)
 Return a single letter to describe the given picture type pict_type.
 
void av_image_fill_max_pixsteps (int max_pixsteps[4], int max_pixstep_comps[4], const AVPixFmtDescriptor *pixdesc)
 Compute the max pixel step for each plane of an image with a format described by pixdesc.
 
int av_image_get_linesize (enum AVPixelFormat pix_fmt, int width, int plane)
 Compute the size of an image line with format pix_fmt and width width for the plane plane.
 
int av_image_fill_linesizes (int linesizes[4], enum AVPixelFormat pix_fmt, int width)
 Fill plane linesizes for an image with pixel format pix_fmt and width width.
 
int av_image_fill_pointers (uint8_t *data[4], enum AVPixelFormat pix_fmt, int height, uint8_t *ptr, const int linesizes[4])
 Fill plane data pointers for an image with pixel format pix_fmt and height height.
 
int av_image_alloc (uint8_t *pointers[4], int linesizes[4], int w, int h, enum AVPixelFormat pix_fmt, int align)
 Allocate an image with size w and h and pixel format pix_fmt, and fill pointers and linesizes accordingly.
 
void av_image_copy_plane (uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize, int bytewidth, int height)
 Copy image plane from src to dst.
 
void av_image_copy (uint8_t *dst_data[4], int dst_linesizes[4], const uint8_t *src_data[4], const int src_linesizes[4], enum AVPixelFormat pix_fmt, int width, int height)
 Copy image in src_data to dst_data.
 
int av_image_fill_arrays (uint8_t *dst_data[4], int dst_linesize[4], const uint8_t *src, enum AVPixelFormat pix_fmt, int width, int height, int align)
 Setup the data pointers and linesizes based on the specified image parameters and the provided array.
 
int av_image_get_buffer_size (enum AVPixelFormat pix_fmt, int width, int height, int align)
 Return the size in bytes of the amount of data required to store an image with the given parameters.
 
int av_image_copy_to_buffer (uint8_t *dst, int dst_size, const uint8_t *const src_data[4], const int src_linesize[4], enum AVPixelFormat pix_fmt, int width, int height, int align)
 Copy image data from an image into a buffer.
 
int av_image_check_size (unsigned int w, unsigned int h, int log_offset, void *log_ctx)
 Check if the given dimension of an image is valid, meaning that all bytes of the image can be addressed with a signed int.
 
int av_image_check_sar (unsigned int w, unsigned int h, AVRational sar)
 Check if the given sample aspect ratio of an image is valid.
 

Detailed Description

AVPicture types, pixel formats and basic image planes manipulation.

Enumeration Type Documentation

Enumerator:
AV_PICTURE_TYPE_NONE 

Undefined.

AV_PICTURE_TYPE_I 

Intra.

AV_PICTURE_TYPE_P 

Predicted.

AV_PICTURE_TYPE_B 

Bi-dir predicted.

AV_PICTURE_TYPE_S 

S(GMC)-VOP MPEG4.

AV_PICTURE_TYPE_SI 

Switching Intra.

AV_PICTURE_TYPE_SP 

Switching Predicted.

AV_PICTURE_TYPE_BI 

BI type.

Definition at line 265 of file avutil.h.

Function Documentation

char av_get_picture_type_char ( enum AVPictureType  pict_type)

Return a single letter to describe the given picture type pict_type.

Parameters
[in]pict_typethe picture type
Returns
a single character representing the picture type, '?' if pict_type is unknown

Definition at line 84 of file utils.c.

Referenced by do_video_stats(), ff_er_frame_end(), ff_flv_decode_picture_header(), ff_h263_show_pict_info(), ff_h264_decode_mb_cavlc(), ff_h264_decode_slice_header(), ff_print_debug_info2(), ff_rate_estimate_qscale(), ff_tlog_ref(), filter_frame(), func_pict_type(), queue_picture(), select_frame(), show_frame(), svq3_decode_frame(), and vc1_decode_frame().

void av_image_fill_max_pixsteps ( int  max_pixsteps[4],
int  max_pixstep_comps[4],
const AVPixFmtDescriptor pixdesc 
)

Compute the max pixel step for each plane of an image with a format described by pixdesc.

The pixel step is the distance in bytes between the first byte of the group of bytes which describe a pixel component and the first byte of the successive group in the same plane for the same component.

Parameters
max_pixstepsan array which is filled with the max pixel step for each plane. Since a plane may contain different pixel components, the computed max_pixsteps[plane] is relative to the component in the plane with the max pixel step.
max_pixstep_compsan array which is filled with the component for each plane which has the max pixel step. May be NULL.

Definition at line 34 of file imgutils.c.

Referenced by av_image_fill_linesizes(), av_image_get_linesize(), config_input(), config_input_main(), config_input_overlay(), config_output(), config_props(), and config_props_output().

int av_image_get_linesize ( enum AVPixelFormat  pix_fmt,
int  width,
int  plane 
)

Compute the size of an image line with format pix_fmt and width width for the plane plane.

Returns
the computed size in bytes

Definition at line 75 of file imgutils.c.

Referenced by av_image_copy(), copy_frame(), copy_picture_field(), decode_thread(), filter_frame(), handle_p_frame_apng(), handle_p_frame_png(), and msrle_decode_frame().

int av_image_fill_linesizes ( int  linesizes[4],
enum AVPixelFormat  pix_fmt,
int  width 
)

Fill plane linesizes for an image with pixel format pix_fmt and width width.

Parameters
linesizesarray to be filled with the linesize for each plane
Returns
>= 0 in case of success, a negative error code otherwise

Definition at line 88 of file imgutils.c.

Referenced by av_image_alloc(), av_image_copy_to_buffer(), av_image_fill_arrays(), config_input(), config_output(), config_props(), doTest(), get_video_buffer(), update_frame_pool(), and video_frame_cksum().

int av_image_fill_pointers ( uint8_t data[4],
enum AVPixelFormat  pix_fmt,
int  height,
uint8_t ptr,
const int  linesizes[4] 
)

Fill plane data pointers for an image with pixel format pix_fmt and height height.

Parameters
datapointers array to be filled with the pointer for each image plane
ptrthe pointer to a buffer which will contain the image
linesizesthe array containing the linesize for each plane, should be filled by av_image_fill_linesizes()
Returns
the size in bytes required for the image buffer, a negative error code in case of failure

Definition at line 110 of file imgutils.c.

Referenced by av_image_alloc(), av_image_fill_arrays(), and update_frame_pool().

int av_image_alloc ( uint8_t pointers[4],
int  linesizes[4],
int  w,
int  h,
enum AVPixelFormat  pix_fmt,
int  align 
)

Allocate an image with size w and h and pixel format pix_fmt, and fill pointers and linesizes accordingly.

The allocated image buffer has to be freed by using av_freep(&pointers[0]).

Parameters
alignthe value to use for buffer size alignment
Returns
the size in bytes required for the image buffer, a negative error code in case of failure

Definition at line 192 of file imgutils.c.

Referenced by avpicture_alloc(), config_input(), config_out_props(), config_props(), ff_load_image(), ff_scale_image(), main(), sws_init_context(), and video_encode_example().

void av_image_copy_plane ( uint8_t dst,
int  dst_linesize,
const uint8_t src,
int  src_linesize,
int  bytewidth,
int  height 
)

Copy image plane from src to dst.

That is, copy "height" number of lines of "bytewidth" bytes each. The first byte of each successive line is separated by *_linesize bytes.

bytewidth must be contained by both absolute values of dst_linesize and src_linesize, otherwise the function behavior is undefined.

Parameters
dst_linesizelinesize for the image plane in dst
src_linesizelinesize for the image plane in src

Definition at line 265 of file imgutils.c.

Referenced by apply_delogo(), apply_unsharp(), av_image_copy(), blend_normal(), blur_image(), copy_field(), copy_fields(), copy_frame(), copy_picture_field(), decode_frame(), dxva2_retrieve_data(), encode_plane(), ff_mpegvideoencdsp_init(), filter_frame(), horizontal_frame_pack(), load_mask(), noise(), nvenc_encode_frame(), paf_video_decode(), pix_decode_frame(), process_frame(), and vertical_frame_pack().

void av_image_copy ( uint8_t dst_data[4],
int  dst_linesizes[4],
const uint8_t src_data[4],
const int  src_linesizes[4],
enum AVPixelFormat  pix_fmt,
int  width,
int  height 
)

Copy image in src_data to dst_data.

Parameters
dst_linesizeslinesizes for the image in dst_data
src_linesizeslinesizes for the image in src_data

Definition at line 280 of file imgutils.c.

Referenced by av_picture_copy(), decklink_write_video_packet(), decode_frame(), decode_packet(), decode_thread(), ff_filter_frame_framed(), ff_h264_decode_slice_header(), ff_load_image(), ff_thread_video_encode_frame(), filter_frame(), fixstride(), frame_copy_video(), vda_retrieve_data(), vp8_decode(), and write_picture().

int av_image_fill_arrays ( uint8_t dst_data[4],
int  dst_linesize[4],
const uint8_t src,
enum AVPixelFormat  pix_fmt,
int  width,
int  height,
int  align 
)

Setup the data pointers and linesizes based on the specified image parameters and the provided array.

The fields of the given image are filled in by using the src address which points to the image data buffer. Depending on the specified pixel format, one or multiple image data pointers and line sizes will be set. If a planar format is specified, several pointers will be set pointing to the different picture planes and the line sizes of the different planes will be stored in the lines_sizes array. Call with !src to get the required size for the src buffer.

To allocate the buffer and fill in the dst_data and dst_linesize in one call, use av_image_alloc().

Parameters
dst_datadata pointers to be filled in
dst_linesizeslinesizes for the image in dst_data to be filled in
srcbuffer which will contain or contains the actual image data, can be NULL
pix_fmtthe pixel format of the image
widththe width of the image in pixels
heightthe height of the image in pixels
alignthe value used in src for linesize alignment
Returns
the size in bytes required for src, a negative error code in case of failure

Definition at line 319 of file imgutils.c.

Referenced by av_image_get_buffer_size(), and avpicture_fill().

int av_image_get_buffer_size ( enum AVPixelFormat  pix_fmt,
int  width,
int  height,
int  align 
)

Return the size in bytes of the amount of data required to store an image with the given parameters.

Parameters
[in]alignthe assumed linesize alignment

Definition at line 337 of file imgutils.c.

Referenced by av_image_copy_to_buffer(), avpicture_get_size(), and write_header().

int av_image_copy_to_buffer ( uint8_t dst,
int  dst_size,
const uint8_t *const  src_data[4],
const int  src_linesize[4],
enum AVPixelFormat  pix_fmt,
int  width,
int  height,
int  align 
)

Copy image data from an image into a buffer.

av_image_get_buffer_size() can be used to compute the required size for the buffer to fill.

Parameters
dsta buffer into which picture data will be copied
dst_sizethe size in bytes of dst
src_datapointers containing the source image data
src_linesizeslinesizes for the image in src_data
pix_fmtthe pixel format of the source image
widththe width of the source image in pixels
heightthe height of the source image in pixels
alignthe assumed linesize alignment for dst
Returns
the number of bytes written to dst, or a negative value (error code) on error

Definition at line 353 of file imgutils.c.

Referenced by avpicture_layout().

int av_image_check_size ( unsigned int  w,
unsigned int  h,
int  log_offset,
void log_ctx 
)
int av_image_check_sar ( unsigned int  w,
unsigned int  h,
AVRational  sar 
)

Check if the given sample aspect ratio of an image is valid.

It is considered invalid if the denominator is 0 or if applying the ratio to the image size would make the smaller dimension less than 1. If the sar numerator is 0, it is considered unknown and will return as valid.

Parameters
wwidth of the image
hheight of the image
sarsample aspect ratio of the image
Returns
0 if valid, a negative AVERROR code otherwise

Definition at line 244 of file imgutils.c.

Referenced by avcodec_open2(), decode_slice_header(), ff_init_buffer_info(), and ff_set_sar().