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GStreamer Good Plugins 0.10 Plugins Reference Manual | |
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| Top | Description | Object Hierarchy | Properties | ||||
GObject
+----GstObject
+----GstElement
+----GstBaseTransform
+----GstVideoFilter
+----GstSMPTEAlpha
"border" gint : Read / Write "depth" gint : Read / Write "position" gdouble : Read / Write "type" GstSMPTEAlphaTransitionType : Read / Write
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.
Here is a pipeline to demonstrate the smpte transition :
gst-launch -v videotestsrc ! smptealpha border=20000 type=44 position=0.5 ! videomixer ! ffmpegcolorspace ! 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.
"border" property "border" gint : Read / Write
The border width of the transition.
Allowed values: >= 0
Default value: 0
"depth" property "depth" gint : Read / Write
Depth of the mask in bits.
Allowed values: [1,24]
Default value: 16
"position" property "position" gdouble : Read / Write
Position of the transition effect.
Allowed values: [0,1]
Default value: 0