# codecalphademux

Extracts the CODEC (typically VP8/VP9) alpha stream stored as meta and exposes it as a stream. This element allow using single stream VP8/9 decoders in order to decode both streams.

## Example launch line

     gst-launch-1.0 -v filesrc location=transparency.webm ! matroskademux !
         codecalphademux name=d
         d.video ! queue ! vp9dec ! autovideosink
         d.alpha ! queue ! vp9dec ! autovideosink

This pipeline splits and decode the video and the alpha stream, showing the result on seperate windows.

## Hierarchy

    GObject
        ╰──GInitiallyUnowned
            ╰──GstObject
                ╰──GstElement
                    ╰──codecalphademux

## Factory details

Authors: – Nicolas Dufresne <nicolas.dufresne></nicolas.dufresne>

Classification: – `Codec/Demuxer`

Rank – none

Plugin – codecalpha

Package – GStreamer Bad Plug-ins

## Pad Templates

### `alpha`

    ANY

Presence – always

Direction – src

Object type – GstPad

### `sink`

    ANY

Presence – always

Direction – sink

Object type – GstPad

### `src`

    ANY

Presence – always

Direction – src

Object type – GstPad

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