org.red5.codec.ScreenVideo2 Maven / Gradle / Ivy
/*
* RED5 Open Source Media Server - https://github.com/Red5/ Copyright 2006-2023 by respective authors (see below). All rights reserved. Licensed under the Apache License, Version
* 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless
* required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
* either express or implied. See the License for the specific language governing permissions and limitations under the License.
*/
package org.red5.codec;
import org.apache.mina.core.buffer.IoBuffer;
/**
* Red5 video codec for the screen capture format.
*
* @author The Red5 Project
* @author Joachim Bauch ([email protected])
* @author Paul Gregoire ([email protected])
*/
public class ScreenVideo2 extends AbstractVideo {
/**
* FLV codec name constant
*/
static final String CODEC_NAME = "ScreenVideo2";
/**
* Block data
*/
private byte[] blockData;
/**
* Block size
*/
private int[] blockSize;
/**
* Video width
*/
private int width;
/**
* Video height
*/
private int height;
/**
* Width info
*/
private int widthInfo;
/**
* Height info
*/
private int heightInfo;
/**
* Block width
*/
private int blockWidth;
/**
* Block height
*/
private int blockHeight;
/**
* Number of blocks
*/
private int blockCount;
/**
* Block data size
*/
private int blockDataSize;
/**
* Total block data size
*/
private int totalBlockDataSize;
/**
* Special Info 1
*/
private byte specInfo1;
/**
* Special Info 2
*/
private byte specInfo2;
{
codec = VideoCodec.SCREEN_VIDEO2;
}
/** {@inheritDoc} */
@Override
public String getName() {
return CODEC_NAME;
}
/** {@inheritDoc} */
@Override
public void reset() {
this.blockData = null;
this.blockSize = null;
this.width = 0;
this.height = 0;
this.widthInfo = 0;
this.heightInfo = 0;
this.blockWidth = 0;
this.blockHeight = 0;
this.blockCount = 0;
this.blockDataSize = 0;
this.totalBlockDataSize = 0;
}
/*
* This uses the same algorithm as "compressBound" from zlib
*/
private static int maxCompressedSize(int size) {
return size + (size >> 12) + (size >> 14) + 11;
}
/**
* Update total block size
*
* @param data
* Byte buffer
*/
private void updateSize(IoBuffer data) {
widthInfo = data.getShort();
heightInfo = data.getShort();
// extract width and height of the frame
width = widthInfo & 0xfff;
height = heightInfo & 0xfff;
// calculate size of blocks
blockWidth = (widthInfo & 0xf000 >> 12) + 1;
blockWidth <<= 4;
blockHeight = (heightInfo & 0xf000 >> 12) + 1;
blockHeight <<= 4;
int xblocks = width / blockWidth;
if ((width % blockWidth) != 0) {
// partial block
xblocks += 1;
}
int yblocks = height / blockHeight;
if ((height % blockHeight) != 0) {
// partial block
yblocks += 1;
}
blockCount = xblocks * yblocks;
int compressedSize = maxCompressedSize(blockWidth * blockHeight * 3);
int totalBlockSize = compressedSize * blockCount;
if (this.totalBlockDataSize != totalBlockSize) {
log.info("Allocating memory for {} compressed blocks.", blockCount);
blockDataSize = compressedSize;
totalBlockDataSize = totalBlockSize;
blockData = new byte[compressedSize * blockCount];
blockSize = new int[compressedSize * blockCount];
// Reset the sizes to zero
for (int idx = 0; idx < blockCount; idx++) {
blockSize[idx] = 0;
}
}
}
/** {@inheritDoc} */
@Override
public boolean addData(IoBuffer data) {
if (!this.canHandleData(data)) {
return false;
}
data.get();
this.updateSize(data);
int idx = 0;
int pos = 0;
byte[] tmpData = new byte[blockDataSize];
// reserved (6) has iframeimage (1) has palleteinfo (1)
specInfo1 = data.get();
int countBlocks = blockCount;
while (data.remaining() > 0 && countBlocks > 0) {
short size = data.getShort();
countBlocks--;
if (size == 0) {
// Block has not been modified
idx += 1;
pos += blockDataSize;
continue;
} else {
// imageformat
specInfo2 = data.get();
size--;
}
// Store new block data
blockSize[idx] = size;
data.get(tmpData, 0, size);
System.arraycopy(tmpData, 0, blockData, pos, size);
idx += 1;
pos += blockDataSize;
}
data.rewind();
return true;
}
/** {@inheritDoc} */
@Override
public IoBuffer getKeyframe() {
IoBuffer result = IoBuffer.allocate(blockDataSize + 11);
result.setAutoExpand(true);
// Header
result.put((byte) (FLV_FRAME_KEY | VideoCodec.SCREEN_VIDEO2.getId()));
// Frame size
result.putShort((short) widthInfo);
result.putShort((short) heightInfo);
// reserved (6) has iframeimage (1) has palleteinfo (1)
result.put(specInfo1);
// Get compressed blocks
byte[] tmpData = new byte[blockDataSize];
int pos = 0;
for (int idx = 0; idx < blockCount; idx++) {
int size = blockSize[idx];
if (size == 0) {
// this should not happen: no data for this block
return null;
}
result.putShort((short) (size + 1));
// IMAGEFORMAT
// reserved(3) color depth(2) has diff blocks(1)
// ZlibPrimeCompressCurrent(1) ZlibPrimeCompressPrevious (1)
result.put(specInfo2);
System.arraycopy(blockData, pos, tmpData, 0, size);
result.put(tmpData, 0, size);
pos += blockDataSize;
}
result.rewind();
return result;
}
@Override
public FrameData[] getKeyframes() {
return blockCount > 0 ? new FrameData[] { new FrameData(getKeyframe()) } : new FrameData[0];
}
}
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