/**
* 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++;
}
@Override
public void readFrame(Buffer buffer) {
// example data:
// --ssBoundary8345
// Content-Type: image/jpeg
// Content-Length: 114587
try {
String line;
// eat leading blank lines
while (true) {
line = readLine(MAX_LINE_LENGTH);
if (line == null) {
buffer.setEOM(true);
buffer.setLength(0);
return;
}
if (!line.trim().equals("")) break; // end of header
}
if (boundary == null) {
boundary = line.trim(); // TODO: we should be able to get
// this from the content type, but
// the content type has this
// stripped out. So we'll just take
// the first nonblank line to be the
// boundary.
// System.out.println("boundary: " + boundary);
} else {
if (!line.trim().equals(boundary)) {
// throw new IOException("Expected boundary: " +
// toPrintable(line));
// TODO: why do we seem to get these when playing back
// mmr files recorded using FmjTranscode?
logger.warning("Expected boundary (frame " + framesRead + "): " + toPrintable(line));
// handle streams that are truncated in the middle of a
// frame:
final int eatResult = eatUntil(boundary); // TODO: no
// need to
// store the
// data
logger.info(
"Ignored bytes (eom after="
+ (eatResult < 0)
+ "): "
+ (eatResult < 0 ? (-1 * eatResult - 1) : eatResult));
if (eatResult < 0) {
buffer.setEOM(true);
buffer.setLength(0);
return;
}
// now read boundary
line = readLine(MAX_LINE_LENGTH);
if (!line.trim().equals(boundary)) {
throw new RuntimeException("No boundary found after eatUntil(boundary)"); // should
// never
// happen
}
}
}
final Properties properties = new Properties();
while (true) {
line = readLine(MAX_LINE_LENGTH);
if (line == null) {
buffer.setEOM(true);
buffer.setLength(0);
return;
}
if (line.trim().equals("")) break; // end of header
if (!parseProperty(line, properties))
throw new IOException("Expected property: " + toPrintable(line));
}
final String contentType = properties.getProperty("Content-Type".toUpperCase());
if (contentType == null) {
logger.warning("Header properties: " + properties);
throw new IOException("Expected Content-Type in header");
}
// check supported content types:
if (!isSupportedFrameContentType(contentType)) {
throw new IOException("Unsupported Content-Type: " + contentType);
}
if (frameContentType == null) {
frameContentType = contentType;
} else {
if (!contentType.equals(frameContentType))
throw new IOException(
"Content type changed during stream from "
+ frameContentType
+ " to "
+ contentType);
}
// TODO: check that size doesn't change throughout
final byte[] data;
final String contentLenStr = properties.getProperty("Content-Length".toUpperCase());
if (contentLenStr != null) { // if we know the content length, use it
final int contentLen;
try {
contentLen = Integer.parseInt(contentLenStr);
} catch (NumberFormatException e) {
throw new IOException("Invalid content length: " + contentLenStr);
}
// now, read the content-length bytes
data = readFully(contentLen); // TODO: don't realloc each
// time
} else {
// if we don't know the content length, just read until we
// find the boundary.
// Some IP cameras don't specify it, like
// http://webcam-1.duesseldorf.it-on.net/cgi-bin/nph-update.cgi
data = readUntil(boundary);
}
// ext
final String timestampStr = properties.getProperty(TIMESTAMP_KEY.toUpperCase());
if (timestampStr != null) {
try {
final long timestamp = Long.parseLong(timestampStr);
buffer.setTimeStamp(timestamp);
} catch (NumberFormatException e) {
logger.log(Level.WARNING, "" + e, e);
}
}
if (data == null) {
buffer.setEOM(true);
buffer.setLength(0);
return;
}
buffer.setData(data);
buffer.setOffset(0);
buffer.setLength(data.length);
++framesRead;
} catch (IOException e) {
throw new RuntimeException(e);
}
}