vf_colordetect.c File Reference

#include <stdbool.h>
#include <stdatomic.h>
#include "config.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "filters.h"
#include "formats.h"
#include "video.h"
#include "vf_colordetect.h"

Go to the source code of this file.

Data Structures
struct	ColorDetectContext

Macros
#define	OFFSET(x)   offsetof(ColorDetectContext, x)
#define	FLAGS   AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM

Enumerations
enum	AlphaMode { ALPHA_NONE = -1, ALPHA_UNDETERMINED = 0, ALPHA_STRAIGHT }
enum	ColorDetectMode { COLOR_DETECT_COLOR_RANGE = 1 << 0, COLOR_DETECT_ALPHA_MODE = 1 << 1 }

Functions
	AVFILTER_DEFINE_CLASS (colordetect)
static int	query_format (const AVFilterContext *ctx, AVFilterFormatsConfig **cfg_in, AVFilterFormatsConfig **cfg_out)
static int	config_input (AVFilterLink *inlink)
static int	detect_range (AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
static int	detect_alpha (AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
static int	filter_frame (AVFilterLink *inlink, AVFrame *in)
static av_cold void	uninit (AVFilterContext *ctx)
av_cold void	ff_color_detect_dsp_init (FFColorDetectDSPContext *dsp, int depth, enum AVColorRange color_range)

Variables
static const AVOption	colordetect_options []
static const AVFilterPad	colordetect_inputs []
const FFFilter	ff_vf_colordetect

Detailed Description

Video color space detector, tries to auto-detect YUV range and alpha mode.

Definition in file vf_colordetect.c.

Macro Definition Documentation

OFFSET

#define OFFSET

(

x

)

offsetof(ColorDetectContext, x)

Definition at line 70 of file vf_colordetect.c.

FLAGS

#define FLAGS   AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM

Definition at line 71 of file vf_colordetect.c.

Enumeration Type Documentation

AlphaMode

enum AlphaMode

Enumerator
ALPHA_NONE
ALPHA_UNDETERMINED
ALPHA_STRAIGHT

Definition at line 42 of file vf_colordetect.c.

ColorDetectMode

enum ColorDetectMode

Enumerator
COLOR_DETECT_COLOR_RANGE
COLOR_DETECT_ALPHA_MODE

Definition at line 49 of file vf_colordetect.c.

Function Documentation

AVFILTER_DEFINE_CLASS()

AVFILTER_DEFINE_CLASS

(

colordetect

)

query_format()

static int query_format ( const AVFilterContext *  ctx, AVFilterFormatsConfig **  cfg_in, AVFilterFormatsConfig **  cfg_out  )

static

Definition at line 83 of file vf_colordetect.c.

config_input()

static int config_input ( AVFilterLink *  inlink )

static

Definition at line 102 of file vf_colordetect.c.

detect_range()

static int detect_range ( AVFilterContext *  ctx, void *  arg, int  jobnr, int  nb_jobs  )

static

Definition at line 136 of file vf_colordetect.c.

Referenced by filter_frame().

detect_alpha()

static int detect_alpha ( AVFilterContext *  ctx, void *  arg, int  jobnr, int  nb_jobs  )

static

To check if a value is out of range, we need to compare the color value against the maximum possible color for a given alpha value. x > ((mpeg_max - mpeg_min) / pixel_max) * a + mpeg_min

This simplifies to: (x - mpeg_min) * pixel_max > (mpeg_max - mpeg_min) * a = P * x - K > Q * a in the below formula.

We subtract an additional offset of (1 << (depth - 1)) to account for rounding errors in the value of x, and an extra safety margin of Q because vf_premultiply.c et al. add an offset of (a >> 1) & 1.

Definition at line 153 of file vf_colordetect.c.

Referenced by filter_frame().

filter_frame()

static int filter_frame ( AVFilterLink *  inlink, AVFrame *  in  )

static

Definition at line 197 of file vf_colordetect.c.

uninit()

static av_cold void uninit ( AVFilterContext *  ctx )

static

Definition at line 211 of file vf_colordetect.c.

ff_color_detect_dsp_init()

av_cold void ff_color_detect_dsp_init	(	FFColorDetectDSPContext *	dsp,
		int	depth,
		enum AVColorRange	color_range
	)

Definition at line 232 of file vf_colordetect.c.

Referenced by check_alpha_detect(), check_range_detect(), and config_input().

Variable Documentation

colordetect_options

const AVOption colordetect_options[]

static

Initial value:

= {
    { "mode", "Image properties to detect", OFFSET(mode), AV_OPT_TYPE_FLAGS, {.i64 = -1}, 0, UINT_MAX, FLAGS, .unit = "mode" },
        { "color_range", "Detect (YUV) color range", 0, AV_OPT_TYPE_CONST, {.i64 = COLOR_DETECT_COLOR_RANGE}, 0, 0, FLAGS, .unit = "mode" },
        { "alpha_mode",  "Detect alpha mode",        0, AV_OPT_TYPE_CONST, {.i64 = COLOR_DETECT_ALPHA_MODE }, 0, 0, FLAGS, .unit = "mode" },
        { "all",         "Detect all supported properties", 0, AV_OPT_TYPE_CONST, {.i64 = -1}, 0, 0, FLAGS, .unit = "mode" },
    { NULL }
}

Definition at line 73 of file vf_colordetect.c.

colordetect_inputs

const AVFilterPad colordetect_inputs[]

static

Initial value:

= {
    {
        .name          = "default",
        .type          = AVMEDIA_TYPE_VIDEO,
        .config_props  = config_input,
        .filter_frame  = filter_frame,
    },
}

Definition at line 250 of file vf_colordetect.c.

ff_vf_colordetect

const FFFilter ff_vf_colordetect

Initial value:

= {
    .p.name        = "colordetect",
    .p.description = NULL_IF_CONFIG_SMALL("Detect video color properties."),
    .p.priv_class  = &colordetect_class,
    .p.flags       = AVFILTER_FLAG_SLICE_THREADS | AVFILTER_FLAG_METADATA_ONLY,
    .priv_size     = sizeof(ColorDetectContext),
    FILTER_INPUTS(colordetect_inputs),
    FILTER_OUTPUTS(ff_video_default_filterpad),
    FILTER_QUERY_FUNC2(query_format),
    .uninit        = uninit,
}

Definition at line 259 of file vf_colordetect.c.