org.webrtc.VideoProcessor Maven / Gradle / Ivy
/*
* Copyright 2019 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
package org.webrtc;
import javax.annotation.Nullable;
/**
* Lightweight abstraction for an object that can receive video frames, process them, and pass them
* on to another object. This object is also allowed to observe capturer start/stop.
*/
public interface VideoProcessor extends CapturerObserver {
public static class FrameAdaptationParameters {
public final int cropX;
public final int cropY;
public final int cropWidth;
public final int cropHeight;
public final int scaleWidth;
public final int scaleHeight;
public final long timestampNs;
public final boolean drop;
public FrameAdaptationParameters(int cropX, int cropY, int cropWidth, int cropHeight,
int scaleWidth, int scaleHeight, long timestampNs, boolean drop) {
this.cropX = cropX;
this.cropY = cropY;
this.cropWidth = cropWidth;
this.cropHeight = cropHeight;
this.scaleWidth = scaleWidth;
this.scaleHeight = scaleHeight;
this.timestampNs = timestampNs;
this.drop = drop;
}
}
/**
* This is a chance to access an unadapted frame. The default implementation applies the
* adaptation and forwards the frame to {@link #onFrameCaptured(VideoFrame)}.
*/
default void onFrameCaptured(VideoFrame frame, FrameAdaptationParameters parameters) {
VideoFrame adaptedFrame = applyFrameAdaptationParameters(frame, parameters);
if (adaptedFrame != null) {
onFrameCaptured(adaptedFrame);
adaptedFrame.release();
}
}
/**
* Set the sink that receives the output from this processor. Null can be passed in to unregister
* a sink. After this call returns, no frames should be delivered to an unregistered sink.
*/
void setSink(@Nullable VideoSink sink);
/**
* Applies the frame adaptation parameters to a frame. Returns null if the frame is meant to be
* dropped. Returns a new frame. The caller is responsible for releasing the returned frame.
*/
public static @Nullable VideoFrame applyFrameAdaptationParameters(
VideoFrame frame, FrameAdaptationParameters parameters) {
if (parameters.drop) {
return null;
}
final VideoFrame.Buffer adaptedBuffer =
frame.getBuffer().cropAndScale(parameters.cropX, parameters.cropY, parameters.cropWidth,
parameters.cropHeight, parameters.scaleWidth, parameters.scaleHeight);
return new VideoFrame(adaptedBuffer, frame.getRotation(), parameters.timestampNs);
}
}