smptealpha

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 GstSMPTEAlpha: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 GstSMPTEAlpha: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.

Hierarchy

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

Factory details

Authors: – Wim Taymans

Classification:Filter/Editor/Video

Rank – none

Plugin – smpte

Package – GStreamer Good Plug-ins

Pad Templates

sink

video/x-raw:
         format: I420
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: YV12
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: AYUV
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: ARGB
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: BGRA
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: RGBA
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: ARGB
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]

Presencealways

Directionsink

Object typeGstPad


src

video/x-raw:
         format: AYUV
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: ARGB
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: BGRA
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: RGBA
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]
video/x-raw:
         format: ARGB
          width: [ 1, 2147483647 ]
         height: [ 1, 2147483647 ]
      framerate: [ 0/1, 2147483647/1 ]

Presencealways

Directionsrc

Object typeGstPad


Properties

border

“border” gint

The border width of the transition

Flags : Read / Write

Default value : 0


depth

“depth” gint

Depth of the mask in bits

Flags : Read / Write

Default value : 16


invert

“invert” gboolean

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

Flags : Read / Write

Default value : false


position

“position” gdouble

Position of the transition effect

Flags : Read / Write

Default value : 0


type

“type” Smptealpha-transition-type *

The type of transition to use

Flags : Read / Write

Default value : bar-wipe-lr (1)


Named constants

Smptealpha-transition-type

Members

bar-wipe-lr (1) – A bar moves from left to right
bar-wipe-tb (2) – A bar moves from top to bottom
box-wipe-tl (3) – A box expands from the upper-left corner to the lower-right corner
box-wipe-tr (4) – A box expands from the upper-right corner to the lower-left corner
box-wipe-br (5) – A box expands from the lower-right corner to the upper-left corner
box-wipe-bl (6) – A box expands from the lower-left corner to the upper-right corner
four-box-wipe-ci (7) – A box shape expands from each of the four corners toward the center
four-box-wipe-co (8) – A box shape expands from the center of each quadrant toward the corners of each quadrant
barndoor-v (21) – A central, vertical line splits and expands toward the left and right edges
barndoor-h (22) – A central, horizontal line splits and expands toward the top and bottom edges
box-wipe-tc (23) – A box expands from the top edge's midpoint to the bottom corners
box-wipe-rc (24) – A box expands from the right edge's midpoint to the left corners
box-wipe-bc (25) – A box expands from the bottom edge's midpoint to the top corners
box-wipe-lc (26) – A box expands from the left edge's midpoint to the right corners
diagonal-tl (41) – A diagonal line moves from the upper-left corner to the lower-right corner
diagonal-tr (42) – A diagonal line moves from the upper right corner to the lower-left corner
bowtie-v (43) – Two wedge shapes slide in from the top and bottom edges toward the center
bowtie-h (44) – Two wedge shapes slide in from the left and right edges toward the center
barndoor-dbl (45) – A diagonal line from the lower-left to upper-right corners splits and expands toward the opposite corners
barndoor-dtl (46) – A diagonal line from upper-left to lower-right corners splits and expands toward the opposite corners
misc-diagonal-dbd (47) – Four wedge shapes split from the center and retract toward the four edges
misc-diagonal-dd (48) – A diamond connecting the four edge midpoints simultaneously contracts toward the center and expands toward the edges
vee-d (61) – A wedge shape moves from top to bottom
vee-l (62) – A wedge shape moves from right to left
vee-u (63) – A wedge shape moves from bottom to top
vee-r (64) – A wedge shape moves from left to right
barnvee-d (65) – A 'V' shape extending from the bottom edge's midpoint to the opposite corners contracts toward the center and expands toward the edges
barnvee-l (66) – A 'V' shape extending from the left edge's midpoint to the opposite corners contracts toward the center and expands toward the edges
barnvee-u (67) – A 'V' shape extending from the top edge's midpoint to the opposite corners contracts toward the center and expands toward the edges
barnvee-r (68) – A 'V' shape extending from the right edge's midpoint to the opposite corners contracts toward the center and expands toward the edges
iris-rect (101) – A rectangle expands from the center.
clock-cw12 (201) – A radial hand sweeps clockwise from the twelve o'clock position
clock-cw3 (202) – A radial hand sweeps clockwise from the three o'clock position
clock-cw6 (203) – A radial hand sweeps clockwise from the six o'clock position
clock-cw9 (204) – A radial hand sweeps clockwise from the nine o'clock position
pinwheel-tbv (205) – Two radial hands sweep clockwise from the twelve and six o'clock positions
pinwheel-tbh (206) – Two radial hands sweep clockwise from the nine and three o'clock positions
pinwheel-fb (207) – Four radial hands sweep clockwise
fan-ct (211) – A fan unfolds from the top edge, the fan axis at the center
fan-cr (212) – A fan unfolds from the right edge, the fan axis at the center
doublefan-fov (213) – Two fans, their axes at the center, unfold from the top and bottom
doublefan-foh (214) – Two fans, their axes at the center, unfold from the left and right
singlesweep-cwt (221) – A radial hand sweeps clockwise from the top edge's midpoint
singlesweep-cwr (222) – A radial hand sweeps clockwise from the right edge's midpoint
singlesweep-cwb (223) – A radial hand sweeps clockwise from the bottom edge's midpoint
singlesweep-cwl (224) – A radial hand sweeps clockwise from the left edge's midpoint
doublesweep-pv (225) – Two radial hands sweep clockwise and counter-clockwise from the top and bottom edges' midpoints
doublesweep-pd (226) – Two radial hands sweep clockwise and counter-clockwise from the left and right edges' midpoints
doublesweep-ov (227) – Two radial hands attached at the top and bottom edges' midpoints sweep from right to left
doublesweep-oh (228) – Two radial hands attached at the left and right edges' midpoints sweep from top to bottom
fan-t (231) – A fan unfolds from the bottom, the fan axis at the top edge's midpoint
fan-r (232) – A fan unfolds from the left, the fan axis at the right edge's midpoint
fan-b (233) – A fan unfolds from the top, the fan axis at the bottom edge's midpoint
fan-l (234) – A fan unfolds from the right, the fan axis at the left edge's midpoint
doublefan-fiv (235) – Two fans, their axes at the top and bottom, unfold from the center
doublefan-fih (236) – Two fans, their axes at the left and right, unfold from the center
singlesweep-cwtl (241) – A radial hand sweeps clockwise from the upper-left corner
singlesweep-cwbl (242) – A radial hand sweeps counter-clockwise from the lower-left corner.
singlesweep-cwbr (243) – A radial hand sweeps clockwise from the lower-right corner
singlesweep-cwtr (244) – A radial hand sweeps counter-clockwise from the upper-right corner
doublesweep-pdtl (245) – Two radial hands attached at the upper-left and lower-right corners sweep down and up
doublesweep-pdbl (246) – Two radial hands attached at the lower-left and upper-right corners sweep down and up
saloondoor-t (251) – Two radial hands attached at the upper-left and upper-right corners sweep down
saloondoor-l (252) – Two radial hands attached at the upper-left and lower-left corners sweep to the right
saloondoor-b (253) – Two radial hands attached at the lower-left and lower-right corners sweep up
saloondoor-r (254) – Two radial hands attached at the upper-right and lower-right corners sweep to the left
windshield-r (261) – Two radial hands attached at the midpoints of the top and bottom halves sweep from right to left
windshield-u (262) – Two radial hands attached at the midpoints of the left and right halves sweep from top to bottom
windshield-v (263) – Two sets of radial hands attached at the midpoints of the top and bottom halves sweep from top to bottom and bottom to top
windshield-h (264) – Two sets of radial hands attached at the midpoints of the left and right halves sweep from left to right and right to left

The results of the search are