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/*
* Copyright 2017 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 android.graphics.Matrix;
import android.opengl.GLES11Ext;
import android.opengl.GLES20;
import androidx.annotation.Nullable;
import java.nio.ByteBuffer;
/**
* Java version of webrtc::VideoFrame and webrtc::VideoFrameBuffer. A difference from the C++
* version is that no explicit tag is used, and clients are expected to use 'instanceof' to find the
* right subclass of the buffer. This allows clients to create custom VideoFrame.Buffer in
* arbitrary format in their custom VideoSources, and then cast it back to the correct subclass in
* their custom VideoSinks. All implementations must also implement the toI420() function,
* converting from the underlying representation if necessary. I420 is the most widely accepted
* format and serves as a fallback for video sinks that can only handle I420, e.g. the internal
* WebRTC software encoders.
*/
public class VideoFrame implements RefCounted {
/**
* Implements image storage medium. Might be for example an OpenGL texture or a memory region
* containing I420-data.
*
* <p>Reference counting is needed since a video buffer can be shared between multiple VideoSinks,
* and the buffer needs to be returned to the VideoSource as soon as all references are gone.
*/
public interface Buffer extends RefCounted {
/**
* Representation of the underlying buffer. Currently, only NATIVE and I420 are supported.
*/
@CalledByNative("Buffer")
@VideoFrameBufferType
default int getBufferType() {
return VideoFrameBufferType.NATIVE;
}
/**
* Resolution of the buffer in pixels.
*/
@CalledByNative("Buffer") int getWidth();
@CalledByNative("Buffer") int getHeight();
/**
* Returns a memory-backed frame in I420 format. If the pixel data is in another format, a
* conversion will take place. All implementations must provide a fallback to I420 for
* compatibility with e.g. the internal WebRTC software encoders.
*
* <p> Conversion may fail, for example if reading the pixel data from a texture fails. If the
* conversion fails, null is returned.
*/
@Nullable @CalledByNative("Buffer") I420Buffer toI420();
@Override @CalledByNative("Buffer") void retain();
@Override @CalledByNative("Buffer") void release();
/**
* Crops a region defined by `cropx`, `cropY`, `cropWidth` and `cropHeight`. Scales it to size
* `scaleWidth` x `scaleHeight`.
*/
@CalledByNative("Buffer")
Buffer cropAndScale(
int cropX, int cropY, int cropWidth, int cropHeight, int scaleWidth, int scaleHeight);
}
/**
* Interface for I420 buffers.
*/
public interface I420Buffer extends Buffer {
@Override
default int getBufferType() {
return VideoFrameBufferType.I420;
}
/**
* Returns a direct ByteBuffer containing Y-plane data. The buffer capacity is at least
* getStrideY() * getHeight() bytes. The position of the returned buffer is ignored and must
* be 0. Callers may mutate the ByteBuffer (eg. through relative-read operations), so
* implementations must return a new ByteBuffer or slice for each call.
*/
@CalledByNative("I420Buffer") ByteBuffer getDataY();
/**
* Returns a direct ByteBuffer containing U-plane data. The buffer capacity is at least
* getStrideU() * ((getHeight() + 1) / 2) bytes. The position of the returned buffer is ignored
* and must be 0. Callers may mutate the ByteBuffer (eg. through relative-read operations), so
* implementations must return a new ByteBuffer or slice for each call.
*/
@CalledByNative("I420Buffer") ByteBuffer getDataU();
/**
* Returns a direct ByteBuffer containing V-plane data. The buffer capacity is at least
* getStrideV() * ((getHeight() + 1) / 2) bytes. The position of the returned buffer is ignored
* and must be 0. Callers may mutate the ByteBuffer (eg. through relative-read operations), so
* implementations must return a new ByteBuffer or slice for each call.
*/
@CalledByNative("I420Buffer") ByteBuffer getDataV();
@CalledByNative("I420Buffer") int getStrideY();
@CalledByNative("I420Buffer") int getStrideU();
@CalledByNative("I420Buffer") int getStrideV();
}
/**
* Interface for buffers that are stored as a single texture, either in OES or RGB format.
*/
public interface TextureBuffer extends Buffer {
enum Type {
OES(GLES11Ext.GL_TEXTURE_EXTERNAL_OES),
RGB(GLES20.GL_TEXTURE_2D);
private final int glTarget;
private Type(final int glTarget) {
this.glTarget = glTarget;
}
public int getGlTarget() {
return glTarget;
}
}
Type getType();
int getTextureId();
/**
* Retrieve the transform matrix associated with the frame. This transform matrix maps 2D
* homogeneous coordinates of the form (s, t, 1) with s and t in the inclusive range [0, 1] to
* the coordinate that should be used to sample that location from the buffer.
*/
Matrix getTransformMatrix();
/**
* Create a new TextureBufferImpl with an applied transform matrix and a new size. The existing
* buffer is unchanged. The given transform matrix is applied first when texture coordinates are
* still in the unmodified [0, 1] range.
*/
default TextureBuffer applyTransformMatrix(
Matrix transformMatrix, int newWidth, int newHeight) {
throw new UnsupportedOperationException("Not implemented");
}
/**
* Returns the width of the texture in memory. This should only be used for downscaling, and you
* should still respect the width from getWidth().
*/
default public int getUnscaledWidth() {
return getWidth();
}
/**
* Returns the height of the texture in memory. This should only be used for downscaling, and
* you should still respect the height from getHeight().
*/
default public int getUnscaledHeight() {
return getHeight();
}
}
private final Buffer buffer;
private final int rotation;
private final long timestampNs;
/**
* Constructs a new VideoFrame backed by the given {@code buffer}.
*
* @note Ownership of the buffer object is tranferred to the new VideoFrame.
*/
@CalledByNative
public VideoFrame(Buffer buffer, int rotation, long timestampNs) {
if (buffer == null) {
throw new IllegalArgumentException("buffer not allowed to be null");
}
if (rotation % 90 != 0) {
throw new IllegalArgumentException("rotation must be a multiple of 90");
}
this.buffer = buffer;
this.rotation = rotation;
this.timestampNs = timestampNs;
}
@CalledByNative
public Buffer getBuffer() {
return buffer;
}
/**
* Rotation of the frame in degrees.
*/
@CalledByNative
public int getRotation() {
return rotation;
}
/**
* Timestamp of the frame in nano seconds.
*/
@CalledByNative
public long getTimestampNs() {
return timestampNs;
}
public int getRotatedWidth() {
if (rotation % 180 == 0) {
return buffer.getWidth();
}
return buffer.getHeight();
}
public int getRotatedHeight() {
if (rotation % 180 == 0) {
return buffer.getHeight();
}
return buffer.getWidth();
}
@Override
public void retain() {
buffer.retain();
}
@Override
@CalledByNative
public void release() {
buffer.release();
}
}