smptealpha

smptealpha — Apply the standard SMPTE transitions as alpha on video images

Properties

gint border Read / Write
gint depth Read / Write
gdouble position Read / Write
GstSMPTEAlphaTransitionType type Read / Write
gboolean invert Read / Write

Types and Values

struct GstSMPTEAlpha

Object Hierarchy

    GObject
    ╰── GInitiallyUnowned
        ╰── GstObject
            ╰── GstElement
                ╰── GstBaseTransform
                    ╰── GstVideoFilter
                        ╰── GstSMPTEAlpha

Description

smptealpha can accept an I420 or AYUV video stream. An alpha channel is added using an effect specific SMPTE mask in the I420 input case. In the AYUV case, the alpha channel is modified using the effect specific SMPTE mask.

The “position” property is a controllabe double between 0.0 and 1.0 that specifies the position in the transition. 0.0 is the start of the transition with the alpha channel to complete opaque where 1.0 has the alpha channel set to completely transparent.

The “depth” property defines the precision in bits of the mask. A higher presision will create a mask with smoother gradients in order to avoid banding.

Sample pipelines

Here is a pipeline to demonstrate the smpte transition :

gst-launch-1.0 -v videotestsrc ! smptealpha border=20000 type=44
position=0.5 ! videomixer ! videoconvert ! ximagesink

This shows a midway bowtie-h transition a from a videotestsrc to a transparent image. The edges of the transition are smoothed with a 20000 big border.

Synopsis

Element Information

plugin

smpte

author

Wim Taymans <wim.taymans@gmail.com>

class

Filter/Editor/Video

Element Pads

name

sink

direction

sink

presence

always

details

video/x-raw, format=(string)I420, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)YV12, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)AYUV, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)ARGB, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)BGRA, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)RGBA, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)ARGB, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

name

src

direction

source

presence

always

details

video/x-raw, format=(string)AYUV, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)ARGB, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)BGRA, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)RGBA, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

video/x-raw, format=(string)ARGB, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

Functions

Types and Values

struct GstSMPTEAlpha

struct GstSMPTEAlpha;

Property Details

The “border” property

  “border”                   gint

The border width of the transition.

Flags: Read / Write

Allowed values: >= 0

Default value: 0


The “depth” property

  “depth”                    gint

Depth of the mask in bits.

Flags: Read / Write

Allowed values: [1,24]

Default value: 16


The “position” property

  “position”                 gdouble

Position of the transition effect.

Flags: Read / Write

Allowed values: [0,1]

Default value: 0


The “type” property

  “type”                     GstSMPTEAlphaTransitionType

The type of transition to use.

Flags: Read / Write

Default value: A bar moves from left to right


The “invert” property

  “invert”                   gboolean

Set to TRUE to invert the transition mask (ie. flip it horizontally).

Flags: Read / Write

Default value: FALSE