/** * 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++; }
/** * Copies the content of the most recently received packet into <tt>data</tt>. * * @param buffer an optional <tt>Buffer</tt> instance associated with the specified <tt>data</tt>, * <tt>offset</tt> and <tt>length</tt> and provided to the method in case the implementation * would like to provide additional <tt>Buffer</tt> properties such as <tt>flags</tt> * @param data the <tt>byte[]</tt> that we'd like to copy the content of the packet to. * @param offset the position where we are supposed to start writing in <tt>data</tt>. * @param length the number of <tt>byte</tt>s available for writing in <tt>data</tt>. * @return the number of bytes read * @throws IOException if <tt>length</tt> is less than the size of the packet. */ protected int read(Buffer buffer, byte[] data, int offset, int length) throws IOException { if (data == null) throw new NullPointerException("data"); if (ioError) return -1; RawPacket pkt; synchronized (pktSyncRoot) { pkt = this.pkt; this.pkt = null; } int pktLength; if (pkt == null) { pktLength = 0; } else { // By default, pkt will be returned to the pool after it was read. boolean poolPkt = true; try { pktLength = pkt.getLength(); if (length < pktLength) { /* * If pkt is still the latest RawPacket made available to * reading, reinstate it for the next invocation of read; * otherwise, return it to the pool. */ poolPkt = false; throw new IOException("Input buffer not big enough for " + pktLength); } else { byte[] pktBuffer = pkt.getBuffer(); if (pktBuffer == null) { throw new NullPointerException( "pkt.buffer null, pkt.length " + pktLength + ", pkt.offset " + pkt.getOffset()); } else { System.arraycopy(pkt.getBuffer(), pkt.getOffset(), data, offset, pktLength); if (buffer != null) buffer.setFlags(pkt.getFlags()); } } } finally { if (!poolPkt) { synchronized (pktSyncRoot) { if (this.pkt == null) this.pkt = pkt; else poolPkt = true; } } if (poolPkt) { // Return pkt to the pool because it was successfully read. poolRawPacket(pkt); } } } return pktLength; }