@Override
public int compare(Long a, Long b) {
if (a.equals(b)) return 0;
else if (a > b) {
if (a - b < 32768) return 1;
else return -1;
} else // a < b
{
if (b - a < 32768) return -1;
else return 1;
}
}
@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);
}
}