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Here is some background information to help explain the situation. I've been tasked to build a whiteboard app. This app would require a device's camera to display the whiteboard in a live stream. This device could be positioned at an angle to the white board and yet still display a "flat" image. Pretty much like taking a picture at an angle and then skewing the image to be flat, as if you took the picture directly front of it.

The question I have is if it is possible to skew the SurfaceView of the camera preview so that I can record a video of a skewed image rather then the image itself?

Hyunwoo Park
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If you send it to a TextureView, rather than a SurfaceView, you can apply a transformation matrix. You can see a trivial example in Grafika's PlayMovieActivity, where adjustAspectRatio() applies a matrix to set the aspect ratio of the video.

If you're not familiar with matrix transformations, take a look at the answers here.

This assumes that you have control over the player, and can send it a "skew this much" value along with the video. To modify the actual video you'll need to apply the transform to the video frames as they're on their way to the encoder. One way to do this would be to send the preview to a SurfaceTexture, draw that on a GLES quad with the appropriate transformation, and capture the GLES rendering with a MediaCodec encoder.

It'll be easier to capture it straight and skew it on playback.

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