/**
* Read screen and store result in native buffer.
*
* @param dim dimension of the video
* @return true if success, false otherwise
*/
private ByteBuffer readScreenNative(Dimension dim) {
int size = dim.width * dim.height * 4 + FFmpeg.FF_INPUT_BUFFER_PADDING_SIZE;
ByteBuffer data = byteBufferPool.getBuffer(size);
data.setLength(size);
/* get desktop screen via native grabber */
boolean b;
try {
b =
desktopInteract.captureScreen(
displayIndex, x, y, dim.width, dim.height, data.getPtr(), data.getLength());
} catch (Throwable t) {
if (t instanceof ThreadDeath) {
throw (ThreadDeath) t;
} else {
b = false;
// logger.error("Failed to grab screen!", t);
}
}
if (!b) {
data.free();
data = null;
}
return data;
}
/**
* Blocks and reads into a <tt>Buffer</tt> from this <tt>PullBufferStream</tt>.
*
* @param buffer the <tt>Buffer</tt> this <tt>PullBufferStream</tt> is to read into
* @throws IOException if an I/O error occurs while this <tt>PullBufferStream</tt> reads into the
* specified <tt>Buffer</tt>
* @see AbstractVideoPullBufferStream#doRead(Buffer)
*/
@Override
protected void doRead(Buffer buffer) throws IOException {
/*
* Determine the Format in which we're expected to output. We cannot
* rely on the Format always being specified in the Buffer because it is
* not its responsibility, the DataSource of this ImageStream knows the
* output Format.
*/
Format format = buffer.getFormat();
if (format == null) {
format = getFormat();
if (format != null) buffer.setFormat(format);
}
if (format instanceof AVFrameFormat) {
Object o = buffer.getData();
AVFrame frame;
if (o instanceof AVFrame) frame = (AVFrame) o;
else {
frame = new AVFrame();
buffer.setData(frame);
}
AVFrameFormat avFrameFormat = (AVFrameFormat) format;
Dimension size = avFrameFormat.getSize();
ByteBuffer data = readScreenNative(size);
if (data != null) {
if (frame.avpicture_fill(data, avFrameFormat) < 0) {
data.free();
throw new IOException("avpicture_fill");
}
} else {
/*
* This can happen when we disconnect a monitor from computer
* before or during grabbing.
*/
throw new IOException("Failed to grab screen.");
}
} else {
byte[] bytes = (byte[]) buffer.getData();
Dimension size = ((VideoFormat) format).getSize();
bytes = readScreen(bytes, size);
buffer.setData(bytes);
buffer.setOffset(0);
buffer.setLength(bytes.length);
}
buffer.setHeader(null);
buffer.setTimeStamp(System.nanoTime());
buffer.setSequenceNumber(seqNo);
buffer.setFlags(Buffer.FLAG_SYSTEM_TIME | Buffer.FLAG_LIVE_DATA);
seqNo++;
}