#include <math.h>
#include "libavutil/avassert.h"
#include "libavutil/imgutils.h"
#include "libavutil/pixdesc.h"
#include "libavutil/opt.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
#include "v360.h"

Data Structures
struct	ThreadData
	Used for passing data between threads. More...

Macros
#define	OFFSET(x) offsetof(V360Context, x)

#define	FLAGS AV_OPT_FLAG_FILTERING_PARAM\|AV_OPT_FLAG_VIDEO_PARAM

#define	TFLAGS AV_OPT_FLAG_FILTERING_PARAM\|AV_OPT_FLAG_VIDEO_PARAM\|AV_OPT_FLAG_RUNTIME_PARAM

#define	DEFINE_REMAP1_LINE(bits, div)

#define	DEFINE_REMAP(ws, bits)
	Generate remapping function with a given window size and pixel depth. More...

#define	DEFINE_REMAP_LINE(ws, bits, div)

Functions
	AVFILTER_DEFINE_CLASS (v360)

static int	query_formats (AVFilterContext *ctx)

void	ff_v360_init (V360Context *s, int depth)

static void	nearest_kernel (float du, float dv, const XYRemap rmap, int16_t u, int16_t v, int16_t ker)
	Save nearest pixel coordinates for remapping. More...

static void	bilinear_kernel (float du, float dv, const XYRemap rmap, int16_t u, int16_t v, int16_t ker)
	Calculate kernel for bilinear interpolation. More...

static void	calculate_lagrange_coeffs (float t, float *coeffs)
	Calculate 1-dimensional lagrange coefficients. More...

static void	lagrange_kernel (float du, float dv, const XYRemap rmap, int16_t u, int16_t v, int16_t ker)
	Calculate kernel for lagrange interpolation. More...

static void	calculate_bicubic_coeffs (float t, float *coeffs)
	Calculate 1-dimensional cubic coefficients. More...

static void	bicubic_kernel (float du, float dv, const XYRemap rmap, int16_t u, int16_t v, int16_t ker)
	Calculate kernel for bicubic interpolation. More...

static void	calculate_lanczos_coeffs (float t, float *coeffs)
	Calculate 1-dimensional lanczos coefficients. More...

static void	lanczos_kernel (float du, float dv, const XYRemap rmap, int16_t u, int16_t v, int16_t ker)
	Calculate kernel for lanczos interpolation. More...

static void	calculate_spline16_coeffs (float t, float *coeffs)
	Calculate 1-dimensional spline16 coefficients. More...

static void	spline16_kernel (float du, float dv, const XYRemap rmap, int16_t u, int16_t v, int16_t ker)
	Calculate kernel for spline16 interpolation. More...

static void	calculate_gaussian_coeffs (float t, float *coeffs)
	Calculate 1-dimensional gaussian coefficients. More...

static void	gaussian_kernel (float du, float dv, const XYRemap rmap, int16_t u, int16_t v, int16_t ker)
	Calculate kernel for gaussian interpolation. More...

static int	mod (int a, int b)
	Modulo operation with only positive remainders. More...

static int	reflecty (int y, int h)
	Reflect y operation. More...

static int	ereflectx (int x, int y, int w, int h)
	Reflect x operation for equirect. More...

static int	reflectx (int x, int y, int w, int h)
	Reflect x operation. More...

static int	get_direction (char c)
	Convert char to corresponding direction. More...

static int	get_rotation (char c)
	Convert char to corresponding rotation angle. More...

static int	get_rorder (char c)
	Convert char to corresponding rotation order. More...

static int	prepare_cube_in (AVFilterContext *ctx)
	Prepare data for processing cubemap input format. More...

static int	prepare_cube_out (AVFilterContext *ctx)
	Prepare data for processing cubemap output format. More...

static void	rotate_cube_face (float uf, float vf, int rotation)

static void	rotate_cube_face_inverse (float uf, float vf, int rotation)

static void	normalize_vector (float *vec)
	Normalize vector. More...

static void	cube_to_xyz (const V360Context s, float uf, float vf, int face, float vec, float scalew, float scaleh)
	Calculate 3D coordinates on sphere for corresponding cubemap position. More...

static void	xyz_to_cube (const V360Context s, const float vec, float uf, float vf, int *direction)
	Calculate cubemap position for corresponding 3D coordinates on sphere. More...

static void	process_cube_coordinates (const V360Context s, float uf, float vf, int direction, float new_uf, float new_vf, int face)
	Find position on another cube face in case of overflow/underflow. More...

static int	cube3x2_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in cubemap3x2 format. More...

static int	xyz_to_cube3x2 (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in cubemap3x2 format for corresponding 3D coordinates on sphere. More...

static int	cube1x6_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in cubemap1x6 format. More...

static int	cube6x1_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in cubemap6x1 format. More...

static int	xyz_to_cube1x6 (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in cubemap1x6 format for corresponding 3D coordinates on sphere. More...

static int	xyz_to_cube6x1 (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in cubemap6x1 format for corresponding 3D coordinates on sphere. More...

static int	equirect_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in equirectangular format. More...

static int	hequirect_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in half equirectangular format. More...

static int	prepare_stereographic_out (AVFilterContext *ctx)
	Prepare data for processing stereographic output format. More...

static int	stereographic_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in stereographic format. More...

static int	prepare_stereographic_in (AVFilterContext *ctx)
	Prepare data for processing stereographic input format. More...

static int	xyz_to_stereographic (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in stereographic format for corresponding 3D coordinates on sphere. More...

static int	xyz_to_equirect (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in equirectangular format for corresponding 3D coordinates on sphere. More...

static int	xyz_to_hequirect (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in half equirectangular format for corresponding 3D coordinates on sphere. More...

static int	prepare_flat_in (AVFilterContext *ctx)
	Prepare data for processing flat input format. More...

static int	xyz_to_flat (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in flat format for corresponding 3D coordinates on sphere. More...

static int	xyz_to_mercator (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in mercator format for corresponding 3D coordinates on sphere. More...

static int	mercator_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in mercator format. More...

static int	xyz_to_ball (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in ball format for corresponding 3D coordinates on sphere. More...

static int	ball_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in ball format. More...

static int	hammer_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in hammer format. More...

static int	xyz_to_hammer (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in hammer format for corresponding 3D coordinates on sphere. More...

static int	sinusoidal_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in sinusoidal format. More...

static int	xyz_to_sinusoidal (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in sinusoidal format for corresponding 3D coordinates on sphere. More...

static int	prepare_eac_in (AVFilterContext *ctx)
	Prepare data for processing equi-angular cubemap input format. More...

static int	prepare_eac_out (AVFilterContext *ctx)
	Prepare data for processing equi-angular cubemap output format. More...

static int	eac_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in equi-angular cubemap format. More...

static int	xyz_to_eac (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in equi-angular cubemap format for corresponding 3D coordinates on sphere. More...

static int	prepare_flat_out (AVFilterContext *ctx)
	Prepare data for processing flat output format. More...

static int	flat_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in flat format. More...

static int	prepare_fisheye_out (AVFilterContext *ctx)
	Prepare data for processing fisheye output format. More...

static int	fisheye_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in fisheye format. More...

static int	prepare_fisheye_in (AVFilterContext *ctx)
	Prepare data for processing fisheye input format. More...

static int	xyz_to_fisheye (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in fisheye format for corresponding 3D coordinates on sphere. More...

static int	pannini_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in pannini format. More...

static int	xyz_to_pannini (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in pannini format for corresponding 3D coordinates on sphere. More...

static int	prepare_cylindrical_out (AVFilterContext *ctx)
	Prepare data for processing cylindrical output format. More...

static int	cylindrical_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in cylindrical format. More...

static int	prepare_cylindrical_in (AVFilterContext *ctx)
	Prepare data for processing cylindrical input format. More...

static int	xyz_to_cylindrical (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in cylindrical format for corresponding 3D coordinates on sphere. More...

static int	perspective_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in perspective format. More...

static int	tetrahedron_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in tetrahedron format. More...

static int	xyz_to_tetrahedron (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in tetrahedron format for corresponding 3D coordinates on sphere. More...

static int	dfisheye_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in dual fisheye format. More...

static int	xyz_to_dfisheye (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in dual fisheye format for corresponding 3D coordinates on sphere. More...

static int	barrel_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in barrel facebook's format. More...

static int	xyz_to_barrel (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in barrel facebook's format for corresponding 3D coordinates on sphere. More...

static int	xyz_to_barrelsplit (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in barrel split facebook's format for corresponding 3D coordinates on sphere. More...

static int	barrelsplit_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in barrel split facebook's format. More...

static int	tspyramid_to_xyz (const V360Context s, int i, int j, int width, int height, float vec)
	Calculate 3D coordinates on sphere for corresponding frame position in tspyramid format. More...

static int	xyz_to_tspyramid (const V360Context s, const float vec, int width, int height, int16_t us[4][4], int16_t vs[4][4], float du, float dv)
	Calculate frame position in tspyramid format for corresponding 3D coordinates on sphere. More...

static void	multiply_matrix (float c[3][3], const float a[3][3], const float b[3][3])

static void	calculate_rotation_matrix (float yaw, float pitch, float roll, float rot_mat[3][3], const int rotation_order[3])
	Calculate rotation matrix for yaw/pitch/roll angles. More...

static void	rotate (const float rot_mat[3][3], float *vec)
	Rotate vector with given rotation matrix. More...

static void	set_mirror_modifier (int h_flip, int v_flip, int d_flip, float *modifier)

static void	mirror (const float modifier, float vec)

static int	allocate_plane (V360Context *s, int sizeof_uv, int sizeof_ker, int sizeof_mask, int p)

static void	fov_from_dfov (int format, float d_fov, float w, float h, float h_fov, float v_fov)

static void	set_dimensions (int outw, int outh, int w, int h, const AVPixFmtDescriptor *desc)

static av_always_inline int	v360_slice (AVFilterContext ctx, void arg, int jobnr, int nb_jobs)

static int	config_output (AVFilterLink *outlink)

static int	filter_frame (AVFilterLink inlink, AVFrame in)

static int	process_command (AVFilterContext ctx, const char cmd, const char args, char res, int res_len, int flags)

static av_cold void	uninit (AVFilterContext *ctx)

Variables
static const AVOption	v360_options []

static const AVFilterPad	inputs []

static const AVFilterPad	outputs []

AVFilter	ff_vf_v360

Detailed Description

360 video conversion filter. Principle of operation:

(for each pixel in output frame) 1) Calculate OpenGL-like coordinates (x, y, z) for pixel position (i, j) 2) Apply 360 operations (rotation, mirror) to (x, y, z) 3) Calculate pixel position (u, v) in input frame 4) Calculate interpolation window and weight for each pixel

(for each frame) 5) Remap input frame to output frame using precalculated data

Definition in file vf_v360.c.

Macro Definition Documentation

◆ OFFSET

#define OFFSET ( x ) offsetof(V360Context, x)

Definition at line 53 of file vf_v360.c.

◆ FLAGS

#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM

Definition at line 54 of file vf_v360.c.

◆ TFLAGS

#define TFLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM

Definition at line 55 of file vf_v360.c.

◆ DEFINE_REMAP1_LINE

#define DEFINE_REMAP1_LINE	(	bits,
		div
	)

Value:

static void remap1_##bits##bit_line_c(uint8_t *dst, int width, const uint8_t *const src, \
                                      ptrdiff_t in_linesize,                             \
                                      const int16_t *const u, const int16_t *const v,    \
                                      const int16_t *const ker)                          \
{                                                                                        \
    const uint##bits##_t *const s = (const uint##bits##_t *const)src;                    \
    uint##bits##_t *d = (uint##bits##_t *)dst;                                           \
                                                                                         \
    in_linesize /= div;                                                                  \
                                                                                         \
    for (int x = 0; x < width; x++)                                                      \
        d[x] = s[v[x] * in_linesize + u[x]];                                             \
}

Definition at line 247 of file vf_v360.c.

◆ DEFINE_REMAP

#define DEFINE_REMAP	(	ws,
		bits
	)

Generate remapping function with a given window size and pixel depth.

Parameters

ws	size of interpolation window
bits	number of bits per pixel

Definition at line 271 of file vf_v360.c.

◆ DEFINE_REMAP_LINE

#define DEFINE_REMAP_LINE	(	ws,
		bits,
		div
	)

Value:

static void remap##ws##_##bits##bit_line_c(uint8_t *dst, int width, const uint8_t *const src, \
                                           ptrdiff_t in_linesize,                             \
                                           const int16_t *const u, const int16_t *const v,    \
                                           const int16_t *const ker)                          \
{                                                                                             \
    const uint##bits##_t *const s = (const uint##bits##_t *const)src;                         \
    uint##bits##_t *d = (uint##bits##_t *)dst;                                                \
                                                                                              \
    in_linesize /= div;                                                                       \
                                                                                              \
    for (int x = 0; x < width; x++) {                                                         \
        const int16_t *const uu = u + x * ws * ws;                                            \
        const int16_t *const vv = v + x * ws * ws;                                            \
        const int16_t *const kker = ker + x * ws * ws;                                        \
        int tmp = 0;                                                                          \
                                                                                              \
        for (int i = 0; i < ws; i++) {                                                        \
            for (int j = 0; j < ws; j++) {                                                    \
                tmp += kker[i * ws + j] * s[vv[i * ws + j] * in_linesize + uu[i * ws + j]];   \
            }                                                                                 \
        }                                                                                     \
                                                                                              \
        d[x] = av_clip_uint##bits(tmp >> 14);                                                 \
    }                                                                                         \
}

Definition at line 325 of file vf_v360.c.

Function Documentation

◆ AVFILTER_DEFINE_CLASS()

AVFILTER_DEFINE_CLASS ( v360 )

◆ query_formats()

static int query_formats ( AVFilterContext * ctx )

static

Definition at line 163 of file vf_v360.c.

◆ ff_v360_init()

void ff_v360_init	(	V360Context *	s,
		int	depth
	)

Definition at line 359 of file vf_v360.c.

du	horizontal relative coordinate
dv	vertical relative coordinate
rmap	calculated 4x4 window
u	u remap data
v	v remap data
ker	ker remap data

x	input horizontal position
y	input vertical position
w	input width
h	input height

s	filter private context
uf	horizontal cubemap coordinate [0, 1)
vf	vertical cubemap coordinate [0, 1)
face	face of cubemap
vec	coordinates on sphere
scalew	scale for uf
scaleh	scale for vf

s	filter private context
vec	coordinated on sphere
uf	horizontal cubemap coordinate [0, 1)
vf	vertical cubemap coordinate [0, 1)
direction	direction of view

s	filter private context
uf	horizontal cubemap coordinate
vf	vertical cubemap coordinate
direction	direction of view
new_uf	new horizontal cubemap coordinate
new_vf	new vertical cubemap coordinate
face	face position on cubemap

s	filter private context
i	horizontal position on frame [0, width)
j	vertical position on frame [0, height)
width	frame width
height	frame height
vec	coordinates on sphere

t	relative coordinate
coeffs	coefficients

t	relative coordinate
coeffs	coefficients

t	relative coordinate
coeffs	coefficients

Data Structures

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ OFFSET

◆ FLAGS

◆ TFLAGS

◆ DEFINE_REMAP1_LINE

◆ DEFINE_REMAP

◆ DEFINE_REMAP_LINE

Function Documentation

◆ AVFILTER_DEFINE_CLASS()

◆ query_formats()

◆ ff_v360_init()

◆ nearest_kernel()

◆ bilinear_kernel()

◆ calculate_lagrange_coeffs()

◆ lagrange_kernel()

◆ calculate_bicubic_coeffs()

◆ bicubic_kernel()

◆ calculate_lanczos_coeffs()

◆ lanczos_kernel()

◆ calculate_spline16_coeffs()

◆ spline16_kernel()

◆ calculate_gaussian_coeffs()

◆ gaussian_kernel()

◆ mod()

◆ reflecty()

◆ ereflectx()

◆ reflectx()

◆ get_direction()

◆ get_rotation()

◆ get_rorder()

◆ prepare_cube_in()

◆ prepare_cube_out()

◆ rotate_cube_face()

◆ rotate_cube_face_inverse()

◆ normalize_vector()

◆ cube_to_xyz()

◆ xyz_to_cube()

◆ process_cube_coordinates()

◆ cube3x2_to_xyz()

◆ xyz_to_cube3x2()

◆ cube1x6_to_xyz()

◆ cube6x1_to_xyz()

◆ xyz_to_cube1x6()

◆ xyz_to_cube6x1()

◆ equirect_to_xyz()

◆ hequirect_to_xyz()

◆ prepare_stereographic_out()

◆ stereographic_to_xyz()

◆ prepare_stereographic_in()

◆ xyz_to_stereographic()

◆ xyz_to_equirect()

◆ xyz_to_hequirect()

◆ prepare_flat_in()

◆ xyz_to_flat()

◆ xyz_to_mercator()

◆ mercator_to_xyz()

◆ xyz_to_ball()

◆ ball_to_xyz()

◆ hammer_to_xyz()

◆ xyz_to_hammer()

◆ sinusoidal_to_xyz()

◆ xyz_to_sinusoidal()

◆ prepare_eac_in()

◆ prepare_eac_out()

◆ eac_to_xyz()

◆ xyz_to_eac()

◆ prepare_flat_out()

◆ flat_to_xyz()

◆ prepare_fisheye_out()

◆ fisheye_to_xyz()

◆ prepare_fisheye_in()

◆ xyz_to_fisheye()

◆ pannini_to_xyz()

◆ xyz_to_pannini()

◆ prepare_cylindrical_out()