vf_drawvg.c File Reference

drawvg filter, draw vector graphics with cairo. More...

#include <cairo.h>
#include <stdbool.h>
#include "libavutil/attributes.h"
#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavutil/bswap.h"
#include "libavutil/eval.h"
#include "libavutil/internal.h"
#include "libavutil/macros.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "libavutil/sfc64.h"
#include "avfilter.h"
#include "filters.h"
#include "textutils.h"
#include "video.h"

Go to the source code of this file.

Data Structures
struct	VGSConstant
	Constants for some commands, like setlinejoin. More...
struct	VGSParameter
struct	VGSCommandSpec
struct	VGSParser
struct	VGSParserToken
struct	VGSArgument
	Command arguments. More...
struct	VGSStatement
	Program statements. More...
struct	VGSProgram
struct	VGSProcedure
	Block assigned to a procedure by a call to the proc command. More...
struct	VGSEvalState
struct	DrawVGContext

Macros
#define	USER_VAR_COUNT   20
	Number of user variables that can be created with setvar.
#define	VAR_COUNT   (VAR_U0 + USER_VAR_COUNT)
	Total number of variables (default- and user-variables).
#define	MAX_COMMAND_PARAMS   8
#define	MAX_PROC_ARGS   (MAX_COMMAND_PARAMS - 2)
#define	VGS_MAX_RECURSION_DEPTH   100
#define	PARAMS(...)
#define	L(...)
#define	R(...)
#define	NONE   PARAMS({ PARAM_END })
#define	N   { PARAM_NUMERIC }
#define	V   { PARAM_VAR_NAME }
#define	P   { PARAM_SUBPROGRAM }
#define	C(c)
#define	WORD_SEPARATOR   " \n\t\r,"
#define	FAIL(err)
#define	RANDOM_STATES   4
	Number of different states for the randomg function.
#define	ASSERT_ARGS(n)
#define	MAY_PRESERVE(funcname)
#define	OPT(name, field, help)

Typedefs
typedef double	cairo_color[4]
	Colors in cairo are defined by 4 values, between 0 and 1.

Enumerations
enum	{   VAR_N , VAR_T , VAR_TS , VAR_W ,   VAR_H , VAR_DURATION , VAR_CX , VAR_CY ,   VAR_I , VAR_U0 }
enum	VGSCommand {   CMD_ARC = 1 , CMD_ARC_NEG , CMD_BREAK , CMD_CIRCLE ,   CMD_CLIP , CMD_CLIP_EO , CMD_CLOSE_PATH , CMD_COLOR_STOP ,   CMD_CURVE_TO , CMD_DEF_HSLA , CMD_DEF_RGBA , CMD_CURVE_TO_REL ,   CMD_ELLIPSE , CMD_FILL , CMD_FILL_EO , CMD_GET_METADATA ,   CMD_HORZ , CMD_HORZ_REL , CMD_IF , CMD_LINEAR_GRAD ,   CMD_LINE_TO , CMD_LINE_TO_REL , CMD_MOVE_TO , CMD_MOVE_TO_REL ,   CMD_NEW_PATH , CMD_PRESERVE , CMD_PRINT , CMD_PROC_ASSIGN ,   CMD_PROC_CALL , CMD_Q_CURVE_TO , CMD_Q_CURVE_TO_REL , CMD_RADIAL_GRAD ,   CMD_RECT , CMD_REPEAT , CMD_RESET_CLIP , CMD_RESET_DASH ,   CMD_RESET_MATRIX , CMD_RESTORE , CMD_ROTATE , CMD_ROUNDEDRECT ,   CMD_SAVE , CMD_SCALE , CMD_SCALEXY , CMD_SET_COLOR ,   CMD_SET_DASH , CMD_SET_DASH_OFFSET , CMD_SET_HSLA , CMD_SET_LINE_CAP ,   CMD_SET_LINE_JOIN , CMD_SET_LINE_WIDTH , CMD_SET_RGBA , CMD_SET_VAR ,   CMD_STROKE , CMD_S_CURVE_TO , CMD_S_CURVE_TO_REL , CMD_TRANSLATE ,   CMD_T_CURVE_TO , CMD_T_CURVE_TO_REL , CMD_VERT , CMD_VERT_REL }

Functions
static double	vgs_fn_pathlen (void *data, double arg)
	Function pathlen(n) for av_expr_eval.
static double	vgs_fn_randomg (void *data, double arg)
	Function randomg(n) for av_expr_eval.
static double	vgs_fn_p (void *data, double x0, double y0)
	Function p(x, y) for av_expr_eval.
static int	vgs_comp_command_spec (const void *cs1, const void *cs2)
	Comparator for VGSCommandDecl, to be used with bsearch(3).
static const struct VGSCommandSpec *	vgs_get_command (const char *name, size_t length)
	Return the specs for the given command, or NULL if the name is not valid.
static int	vgs_cmd_change_path (enum VGSCommand cmd)
	Return 1 if the command changes the current path in the cairo context.
static av_always_inline void	color_copy (cairo_color *dest, const cairo_color *src)
static av_always_inline void	color_reset (cairo_color *const dest)
static int	vgs_token_is_string (const struct VGSParserToken *token, const char *str)
	Check if token is the value of str.
static void	vgs_token_span (const struct VGSParser *parser, const struct VGSParserToken *token, size_t *line, size_t *column)
	Compute the line/column numbers of the given token.
static	av_printf_format (4, 5)
static int	vgs_parser_next_token (void *log_ctx, struct VGSParser *parser, struct VGSParserToken *token, int advance)
	Return the next token in the source.
static void	vgs_free (struct VGSProgram *program)
	Release the memory allocated by the program.
static int	vgs_parse (void *log_ctx, struct VGSParser *parser, struct VGSProgram *program, int subprogram)
	Build a program by parsing a script.
static void	vgs_statement_free (struct VGSStatement *stm)
static int	vgs_parse_color (void *log_ctx, struct VGSArgument *arg, const struct VGSParser *parser, const struct VGSParserToken *token)
static int	vgs_parse_numeric_argument (void *log_ctx, struct VGSParser *parser, struct VGSArgument *arg, int metadata, bool accept_colors)
	Consume the next argument as a numeric value, and store it in arg.
static int	vgs_parser_can_repeat_cmd (void *log_ctx, struct VGSParser *parser, bool accept_colors)
	Check if the next token is a numeric value (or a color, if accept_colors is true), so the last command must be repeated.
static int	vgs_is_valid_identifier (const struct VGSParserToken *token)
static int	vgs_parse_statement (void *log_ctx, struct VGSParser *parser, struct VGSProgram *program, const struct VGSCommandSpec *decl)
	Extract the arguments for a command, and add a new statement to the program.
static void	vgs_parser_init (struct VGSParser *parser, const char *source)
static void	vgs_parser_free (struct VGSParser *parser)
static int	vgs_eval_state_init (struct VGSEvalState *state, const struct VGSProgram *program, void *log_ctx, AVFrame *frame)
static void	vgs_eval_state_free (struct VGSEvalState *state)
static void	draw_ellipse (cairo_t *c, double x, double y, double rx, double ry)
	Draw an ellipse.
static void	draw_quad_curve_to (struct VGSEvalState *state, int relative, double x1, double y1, double x, double y)
	Draw a quadratic bezier from the current point to x, y, The control point is specified by x1, y1.
static void	draw_cubic_curve_to (struct VGSEvalState *state, int relative, double x1, double y1, double x2, double y2, double x, double y)
	Similar to quad_curve_to, but for cubic curves.
static void	draw_rounded_rect (cairo_t *c, double x, double y, double width, double height, double radius)
static void	hsl2rgb (double h, double s, double l, double *pr, double *pg, double *pb)
static int	vgs_eval (struct VGSEvalState *state, const struct VGSProgram *program, int stack_level)
	Interpreter for VGSProgram.
	AVFILTER_DEFINE_CLASS (drawvg)
static cairo_format_t	cairo_format_from_pix_fmt (DrawVGContext *ctx, enum AVPixelFormat format)
static int	drawvg_filter_frame (AVFilterLink *inlink, AVFrame *frame)
static int	drawvg_config_props (AVFilterLink *inlink)
static av_cold int	drawvg_init (AVFilterContext *ctx)
static av_cold void	drawvg_uninit (AVFilterContext *ctx)

Variables
static const char *const	vgs_default_vars []
static const char *const	vgs_func1_names []
static double(*const	vgs_func1_impls [])(void *, double)
static const char *const	vgs_func2_names []
static double(*const	vgs_func2_impls [])(void *, double, double)
static const struct VGSConstant	vgs_consts_line_cap []
static const struct VGSConstant	vgs_consts_line_join []
static const struct VGSCommandSpec	vgs_commands []
static const AVOption	drawvg_options []
static enum AVPixelFormat	drawvg_pix_fmts []
static const AVFilterPad	drawvg_inputs []
const FFFilter	ff_vf_drawvg

Detailed Description

drawvg filter, draw vector graphics with cairo.

This file contains the parser and the interpreter for VGS, and the AVClass definitions for the drawvg filter.

Definition in file vf_drawvg.c.

Macro Definition Documentation

USER_VAR_COUNT

#define USER_VAR_COUNT   20

Number of user variables that can be created with setvar.

It is possible to allow any number of variables, but this approach simplifies the implementation, and 20 variables is more than enough for the expected use of this filter.

Definition at line 77 of file vf_drawvg.c.

Referenced by main(), vgs_eval(), and vgs_parse_statement().

VAR_COUNT

#define VAR_COUNT   (VAR_U0 + USER_VAR_COUNT)

Total number of variables (default- and user-variables).

Definition at line 80 of file vf_drawvg.c.

Referenced by check_script(), vgs_eval(), vgs_parse_numeric_argument(), vgs_parse_statement(), vgs_parser_can_repeat_cmd(), and vgs_parser_free().

MAX_COMMAND_PARAMS

#define MAX_COMMAND_PARAMS   8

Definition at line 240 of file vf_drawvg.c.

Referenced by vgs_eval(), and vgs_parse_statement().

MAX_PROC_ARGS

#define MAX_PROC_ARGS   (MAX_COMMAND_PARAMS - 2)

Definition at line 246 of file vf_drawvg.c.

Referenced by vgs_eval(), and vgs_parse_statement().

VGS_MAX_RECURSION_DEPTH

#define VGS_MAX_RECURSION_DEPTH   100

Definition at line 248 of file vf_drawvg.c.

Referenced by vgs_eval(), and vgs_parse().

PARAMS

#define PARAMS

(

...

)

Value:

(const struct VGSParameter[]){ __VA_ARGS__ }

Definition at line 259 of file vf_drawvg.c.

L

#define L

(

...

)

Value:

PARAMS(__VA_ARGS__, { PARAM_END })

Definition at line 260 of file vf_drawvg.c.

R

#define R

(

...

)

Value:

PARAMS(__VA_ARGS__, { PARAM_MAY_REPEAT })

Definition at line 261 of file vf_drawvg.c.

NONE

#define NONE   PARAMS({ PARAM_END })

Definition at line 262 of file vf_drawvg.c.

Referenced by config_filter(), convert_width2qfactor(), fade_gain(), init(), submit_frame(), and uninit().

N

#define N   { PARAM_NUMERIC }

Definition at line 265 of file vf_drawvg.c.

V

#define V   { PARAM_VAR_NAME }

Definition at line 266 of file vf_drawvg.c.

P

#define P   { PARAM_SUBPROGRAM }

Definition at line 267 of file vf_drawvg.c.

C

#define C

(

c

)

Value:

{ PARAM_CONSTANT, .constants = c }

Definition at line 268 of file vf_drawvg.c.

WORD_SEPARATOR

#define WORD_SEPARATOR   " \n\t\r,"

Referenced by vgs_parser_next_token().

FAIL

#define FAIL

(

err

)

Value:

        do {                                \
            vgs_statement_free(&statement); \
            return AVERROR(err);            \
        } while(0)

Referenced by vgs_parse_statement().

RANDOM_STATES

#define RANDOM_STATES   4

Number of different states for the randomg function.

Definition at line 1417 of file vf_drawvg.c.

ASSERT_ARGS

#define ASSERT_ARGS

(

n

)

Value:

av_assert0(statement->args_count == n)

Referenced by vgs_eval().

MAY_PRESERVE

#define MAY_PRESERVE

(

funcname

)

Value:

        do {                                           \
            if (state->preserve_path) {                \
                state->preserve_path = 0;              \
                funcname##_preserve(state->cairo_ctx); \
            } else {                                   \
                funcname(state->cairo_ctx);            \
            }                                          \
        } while(0)

Referenced by vgs_eval().

OPT

#define OPT	(		name,
			field,
			help )

Value:

    {                                   \
        name,                           \
        help,                           \
        offsetof(DrawVGContext, field), \
        AV_OPT_TYPE_STRING,             \
        { .str = NULL },                \
        0, 0,                           \
        AV_OPT_FLAG_FILTERING_PARAM     \
           | AV_OPT_FLAG_VIDEO_PARAM    \
    }

Definition at line 2651 of file vf_drawvg.c.

Typedef Documentation

cairo_color

typedef double cairo_color[4]

Colors in cairo are defined by 4 values, between 0 and 1.

Computed colors (either by #RRGGBB expressions, or by commands like defhsla) are stored in the values that will be sent to Cairo.

Definition at line 418 of file vf_drawvg.c.

Enumeration Type Documentation

anonymous enum

anonymous enum

Enumerator
VAR_N	Frame number.
VAR_T	Timestamp in seconds.
VAR_TS	Time in seconds of the first frame.
VAR_W	Frame width.
VAR_H	Frame height.
VAR_DURATION	Frame duration.
VAR_CX	X coordinate for current point.
VAR_CY	Y coordinate for current point.
VAR_I	Loop counter, to use with repeat {}.
VAR_U0	User variables.

Definition at line 59 of file vf_drawvg.c.

VGSCommand

enum VGSCommand

Enumerator
CMD_ARC	arc (cx cy radius angle1 angle2)
CMD_ARC_NEG	arcn (cx cy radius angle1 angle2)
CMD_BREAK	break
CMD_CIRCLE	circle (cx cy radius)
CMD_CLIP	clip
CMD_CLIP_EO	eoclip
CMD_CLOSE_PATH	Z, z, closepath.
CMD_COLOR_STOP	colorstop (offset color)
CMD_CURVE_TO	C, curveto (x1 y1 x2 y2 x y)
CMD_DEF_HSLA	defhsla (varname h s l a)
CMD_DEF_RGBA	defrgba (varname r g b a)
CMD_CURVE_TO_REL	c, rcurveto (dx1 dy1 dx2 dy2 dx dy)
CMD_ELLIPSE	ellipse (cx cy rx ry)
CMD_FILL	fill
CMD_FILL_EO	eofill
CMD_GET_METADATA	getmetadata varname key
CMD_HORZ	H (x)
CMD_HORZ_REL	h (dx)
CMD_IF	if (condition) { subprogram }
CMD_LINEAR_GRAD	lineargrad (x0 y0 x1 y1)
CMD_LINE_TO	L, lineto (x y)
CMD_LINE_TO_REL	l, rlineto (dx dy)
CMD_MOVE_TO	M, moveto (x y)
CMD_MOVE_TO_REL	m, rmoveto (dx dy)
CMD_NEW_PATH	newpath
CMD_PRESERVE	preserve
CMD_PRINT	print (expr)*
CMD_PROC_ASSIGN	proc name varnames* { subprogram }
CMD_PROC_CALL	call name (expr)*
CMD_Q_CURVE_TO	Q (x1 y1 x y)
CMD_Q_CURVE_TO_REL	q (dx1 dy1 dx dy)
CMD_RADIAL_GRAD	radialgrad (cx0 cy0 radius0 cx1 cy1 radius1)
CMD_RECT	rect (x y width height)
CMD_REPEAT	repeat (count) { subprogram }
CMD_RESET_CLIP	resetclip
CMD_RESET_DASH	resetdash
CMD_RESET_MATRIX	resetmatrix
CMD_RESTORE	restore
CMD_ROTATE	rotate (angle)
CMD_ROUNDEDRECT	roundedrect (x y width height radius)
CMD_SAVE	save
CMD_SCALE	scale (s)
CMD_SCALEXY	scalexy (sx sy)
CMD_SET_COLOR	setcolor (color)
CMD_SET_DASH	setdash (length)
CMD_SET_DASH_OFFSET	setdashoffset (offset)
CMD_SET_HSLA	sethsla (h s l a)
CMD_SET_LINE_CAP	setlinecap (cap)
CMD_SET_LINE_JOIN	setlinejoin (join)
CMD_SET_LINE_WIDTH	setlinewidth (width)
CMD_SET_RGBA	setrgba (r g b a)
CMD_SET_VAR	setvar (varname value)
CMD_STROKE	stroke
CMD_S_CURVE_TO	S (x2 y2 x y)
CMD_S_CURVE_TO_REL	s (dx2 dy2 dx dy)
CMD_TRANSLATE	translate (tx ty)
CMD_T_CURVE_TO	T (x y)
CMD_T_CURVE_TO_REL	t (dx dy)
CMD_VERT	V (y)
CMD_VERT_REL	v (dy)

Definition at line 135 of file vf_drawvg.c.

Function Documentation

vgs_fn_pathlen()

static double vgs_fn_pathlen ( void * data, double arg )

static

Function pathlen(n) for av_expr_eval.

Compute the length of the current path in the cairo context. If n > 0, it is the maximum number of segments to be added to the length.

Definition at line 1493 of file vf_drawvg.c.

vgs_fn_randomg()

static double vgs_fn_randomg ( void * data, double arg )

static

Function randomg(n) for av_expr_eval.

Compute a random value between 0 and 1. Similar to random(), but the state is global to the VGS program.

The last 2 bits of the integer representation of the argument are used as the state index. If the state is not initialized, the argument is the seed for that state.

Definition at line 1557 of file vf_drawvg.c.

vgs_fn_p()

static double vgs_fn_p ( void * data, double x0, double y0 )

static

Function p(x, y) for av_expr_eval.

Return the pixel color in 0xRRGGBBAA format.

The transformation matrix is applied to the given coordinates.

If the coordinates are outside the frame, return NAN.

Definition at line 1581 of file vf_drawvg.c.

vgs_comp_command_spec()

static int vgs_comp_command_spec ( const void * cs1, const void * cs2 )

static

Comparator for VGSCommandDecl, to be used with bsearch(3).

Definition at line 352 of file vf_drawvg.c.

Referenced by check_sorted_cmds_array(), and vgs_get_command().

vgs_get_command()

static const struct VGSCommandSpec * vgs_get_command ( const char * name, size_t length )

static

Return the specs for the given command, or NULL if the name is not valid.

The implementation assumes that vgs_commands is sorted by name.

Definition at line 362 of file vf_drawvg.c.

Referenced by vgs_parse(), and vgs_parser_can_repeat_cmd().

vgs_cmd_change_path()

static int vgs_cmd_change_path ( enum VGSCommand cmd )

static

Return 1 if the command changes the current path in the cairo context.

Definition at line 382 of file vf_drawvg.c.

Referenced by vgs_eval().

color_copy()

static av_always_inline void color_copy ( cairo_color * dest, const cairo_color * src )

static

Definition at line 420 of file vf_drawvg.c.

Referenced by vgs_eval().

color_reset()

static av_always_inline void color_reset ( cairo_color *const dest )

static

Definition at line 424 of file vf_drawvg.c.

Referenced by vgs_eval(), and vgs_eval_state_init().

vgs_token_is_string()

static int vgs_token_is_string ( const struct VGSParserToken * token, const char * str )

static

Check if token is the value of str.

Definition at line 485 of file vf_drawvg.c.

Referenced by vgs_parse_numeric_argument(), vgs_parse_statement(), and vgs_parser_can_repeat_cmd().

vgs_token_span()

static void vgs_token_span ( const struct VGSParser * parser, const struct VGSParserToken * token, size_t * line, size_t * column )

static

Compute the line/column numbers of the given token.

Definition at line 491 of file vf_drawvg.c.

Referenced by av_printf_format(), and vgs_parse_numeric_argument().

av_printf_format()

static av_printf_format ( 4 , 5  )

static

Definition at line 514 of file vf_drawvg.c.

vgs_parser_next_token()

static int vgs_parser_next_token ( void * log_ctx, struct VGSParser * parser, struct VGSParserToken * token, int advance )

static

Return the next token in the source.

Parameters

[out]	token	Next token.
[in]	advance	If true, the cursor is updated after finding a token.

Returns

0 on success, and a negative AVERROR code on failure.

Definition at line 544 of file vf_drawvg.c.

Referenced by vgs_parse(), vgs_parse_numeric_argument(), vgs_parse_statement(), and vgs_parser_can_repeat_cmd().

vgs_free()

static void vgs_free ( struct VGSProgram * program )

static

Release the memory allocated by the program.

Definition at line 731 of file vf_drawvg.c.

Referenced by check_script(), drawvg_uninit(), vgs_parse(), and vgs_statement_free().

vgs_parse()

static int vgs_parse ( void * log_ctx, struct VGSParser * parser, struct VGSProgram * program, int subprogram )

static

Build a program by parsing a script.

subprogram must be true when the function is called to parse the body of a block (like if or proc commands).

Return 0 on success, and a negative AVERROR code on failure.

Definition at line 1330 of file vf_drawvg.c.

Referenced by check_script(), drawvg_init(), and vgs_parse_statement().

vgs_statement_free()

static void vgs_statement_free ( struct VGSStatement * stm )

static

Definition at line 702 of file vf_drawvg.c.

Referenced by vgs_free().

vgs_parse_color()

static int vgs_parse_color ( void * log_ctx, struct VGSArgument * arg, const struct VGSParser * parser, const struct VGSParserToken * token )

static

Definition at line 748 of file vf_drawvg.c.

Referenced by vgs_parse_numeric_argument(), and vgs_parse_statement().

vgs_parse_numeric_argument()

static int vgs_parse_numeric_argument ( void * log_ctx, struct VGSParser * parser, struct VGSArgument * arg, int metadata, bool accept_colors )

static

Consume the next argument as a numeric value, and store it in arg.

Return 0 on success, and a negative AVERROR code on failure.

Definition at line 777 of file vf_drawvg.c.

Referenced by vgs_parse_statement().

vgs_parser_can_repeat_cmd()

static int vgs_parser_can_repeat_cmd ( void * log_ctx, struct VGSParser * parser, bool accept_colors )

static

Check if the next token is a numeric value (or a color, if accept_colors is true), so the last command must be repeated.

Definition at line 890 of file vf_drawvg.c.

Referenced by vgs_parse_statement().

vgs_is_valid_identifier()

static int vgs_is_valid_identifier ( const struct VGSParserToken * token )

static

Definition at line 937 of file vf_drawvg.c.

Referenced by vgs_parse_statement().

vgs_parse_statement()

static int vgs_parse_statement ( void * log_ctx, struct VGSParser * parser, struct VGSProgram * program, const struct VGSCommandSpec * decl )

static

Extract the arguments for a command, and add a new statement to the program.

On success, return 0.

Definition at line 961 of file vf_drawvg.c.

Referenced by vgs_parse().

vgs_parser_init()

static void vgs_parser_init ( struct VGSParser * parser, const char * source )

static

Definition at line 1298 of file vf_drawvg.c.

Referenced by check_script(), and drawvg_init().

vgs_parser_free()

static void vgs_parser_free ( struct VGSParser * parser )

static

Definition at line 1311 of file vf_drawvg.c.

Referenced by check_script(), and drawvg_init().

vgs_eval_state_init()

static int vgs_eval_state_init ( struct VGSEvalState * state, const struct VGSProgram * program, void * log_ctx, AVFrame * frame )

static

Definition at line 1645 of file vf_drawvg.c.

Referenced by check_script(), and drawvg_filter_frame().

vgs_eval_state_free()

static void vgs_eval_state_free ( struct VGSEvalState * state )

static

Definition at line 1676 of file vf_drawvg.c.

Referenced by check_script(), and drawvg_filter_frame().

draw_ellipse()

static void draw_ellipse ( cairo_t * c, double x, double y, double rx, double ry )

static

Draw an ellipse.

x/y specifies the center, and rx/ry the radius of the ellipse on the x/y axis.

Cairo does not provide a native way to create an ellipse, but it can be done by scaling the Y axis with the transformation matrix.

Definition at line 1691 of file vf_drawvg.c.

Referenced by vgs_eval().

draw_quad_curve_to()

static void draw_quad_curve_to ( struct VGSEvalState * state, int relative, double x1, double y1, double x, double y )

static

Draw a quadratic bezier from the current point to x, y, The control point is specified by x1, y1.

If the control point is NAN, use the reflected point.

cairo only supports cubic cuvers, so control points must be adjusted to simulate the behaviour in SVG.

Definition at line 1713 of file vf_drawvg.c.

Referenced by vgs_eval().

draw_cubic_curve_to()

static void draw_cubic_curve_to ( struct VGSEvalState * state, int relative, double x1, double y1, double x2, double y2, double x, double y )

static

Similar to quad_curve_to, but for cubic curves.

Definition at line 1762 of file vf_drawvg.c.

Referenced by vgs_eval().

draw_rounded_rect()

static void draw_rounded_rect ( cairo_t * c, double x, double y, double width, double height, double radius )

static

Definition at line 1809 of file vf_drawvg.c.

Referenced by vgs_eval().

hsl2rgb()

static void hsl2rgb ( double h, double s, double l, double * pr, double * pg, double * pb )

static

Definition at line 1827 of file vf_drawvg.c.

Referenced by vgs_eval().

vgs_eval()

static int vgs_eval ( struct VGSEvalState * state, const struct VGSProgram * program, int stack_level )

static

Interpreter for VGSProgram.

Its implementation is a simple switch-based dispatch.

To evaluate blocks (like if or call), it makes a recursive call with the subprogram allocated to the block.

Definition at line 1901 of file vf_drawvg.c.

Referenced by check_script(), drawvg_filter_frame(), and vgs_eval().

AVFILTER_DEFINE_CLASS()

AVFILTER_DEFINE_CLASS

(

drawvg

)

cairo_format_from_pix_fmt()

static cairo_format_t cairo_format_from_pix_fmt ( DrawVGContext * ctx, enum AVPixelFormat format )

static

Definition at line 2684 of file vf_drawvg.c.

Referenced by drawvg_config_props().

drawvg_filter_frame()

static int drawvg_filter_frame ( AVFilterLink * inlink, AVFrame * frame )

static

Definition at line 2708 of file vf_drawvg.c.

drawvg_config_props()

static int drawvg_config_props ( AVFilterLink * inlink )

static

Definition at line 2767 of file vf_drawvg.c.

drawvg_init()

static av_cold int drawvg_init ( AVFilterContext * ctx )

static

Definition at line 2781 of file vf_drawvg.c.

drawvg_uninit()

static av_cold void drawvg_uninit ( AVFilterContext * ctx )

static

Definition at line 2816 of file vf_drawvg.c.

Variable Documentation

vgs_default_vars

const char* const vgs_default_vars[]

static

Initial value:

= {
    "n",
    "t",
    "ts",
    "w",
    "h",
    "duration",
    "cx",
    "cy",
    "i",
    NULL, 
}

Definition at line 82 of file vf_drawvg.c.

Referenced by vgs_parser_init().

vgs_func1_names

const char* const vgs_func1_names[]

static

Initial value:

= {
    "pathlen",
    "randomg",
    NULL,
}

Definition at line 97 of file vf_drawvg.c.

Referenced by vgs_parse_numeric_argument().

vgs_func1_impls

double(*const vgs_func1_impls[])(void *, double) ( void * , double  )

static

Initial value:

= {
    vgs_fn_pathlen,
    vgs_fn_randomg,
    NULL,
}

Definition at line 106 of file vf_drawvg.c.

Referenced by vgs_parse_numeric_argument().

vgs_func2_names

const char* const vgs_func2_names[]

static

Initial value:

= {
    "p",
    NULL,
}

Definition at line 112 of file vf_drawvg.c.

Referenced by vgs_parse_numeric_argument().

vgs_func2_impls

double(*const vgs_func2_impls[])(void *, double, double) ( void * , double , double  )

static

Initial value:

= {
    vgs_fn_p,
    NULL,
}

Definition at line 119 of file vf_drawvg.c.

Referenced by vgs_parse_numeric_argument().

vgs_consts_line_cap

const struct VGSConstant vgs_consts_line_cap[]

static

Initial value:

= {
    { "butt", CAIRO_LINE_CAP_BUTT },
    { "round", CAIRO_LINE_CAP_ROUND },
    { "square", CAIRO_LINE_CAP_SQUARE },
    { NULL, 0 },
}

Definition at line 204 of file vf_drawvg.c.

vgs_consts_line_join

const struct VGSConstant vgs_consts_line_join[]

static

Initial value:

= {
    { "bevel", CAIRO_LINE_JOIN_BEVEL },
    { "miter", CAIRO_LINE_JOIN_MITER },
    { "round", CAIRO_LINE_JOIN_ROUND },
    { NULL, 0 },
}

Definition at line 211 of file vf_drawvg.c.

vgs_commands

const struct VGSCommandSpec vgs_commands[]

static

Definition at line 273 of file vf_drawvg.c.

Referenced by check_sorted_cmds_array(), and vgs_get_command().

drawvg_options

const AVOption drawvg_options[]

static

Initial value:

= {
    OPT("script", script_text, "script source to draw the graphics"),
    OPT("s",      script_text, "script source to draw the graphics"),
    OPT("file",   script_file, "file to load the script source"),
    { NULL }
}

Definition at line 2663 of file vf_drawvg.c.

drawvg_pix_fmts

enum AVPixelFormat drawvg_pix_fmts[]

static

Initial value:

= {
    AV_PIX_FMT_RGB32,
    AV_PIX_FMT_0RGB32,
    AV_PIX_FMT_RGB565,
    AV_PIX_FMT_X2RGB10,
    AV_PIX_FMT_NONE
}

Definition at line 2675 of file vf_drawvg.c.

Referenced by cairo_format_from_pix_fmt().

drawvg_inputs

const AVFilterPad drawvg_inputs[]

static

Initial value:

= {
    {
        .name         = "default",
        .type         = AVMEDIA_TYPE_VIDEO,
        .flags        = AVFILTERPAD_FLAG_NEEDS_WRITABLE,
        .filter_frame = drawvg_filter_frame,
        .config_props = drawvg_config_props,
    },
}

Definition at line 2821 of file vf_drawvg.c.

ff_vf_drawvg

const FFFilter ff_vf_drawvg

Initial value:

= {
    .p.name        = "drawvg",
    .p.description = NULL_IF_CONFIG_SMALL("Draw vector graphics on top of video frames."),
    .p.priv_class  = &drawvg_class,
    .p.flags       = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
    .priv_size     = sizeof(DrawVGContext),
    .init          = drawvg_init,
    .uninit        = drawvg_uninit,
    FILTER_INPUTS(drawvg_inputs),
    FILTER_OUTPUTS(ff_video_default_filterpad),
    FILTER_PIXFMTS_ARRAY(drawvg_pix_fmts),
}

Definition at line 2831 of file vf_drawvg.c.