diff options
| -rw-r--r-- | mjpeg-proxy.js | 185 |
1 files changed, 98 insertions, 87 deletions
diff --git a/mjpeg-proxy.js b/mjpeg-proxy.js index bd4de7c..9d2d380 100644 --- a/mjpeg-proxy.js +++ b/mjpeg-proxy.js @@ -36,109 +36,120 @@ function extractBoundary(contentType) { return contentType.substring(startIndex + 9, endIndex).replace(/"/gi,''); } -var MjpegProxy = exports.MjpegProxy = function(mjpegUrl) { +var MjpegProxy = exports.MjpegProxy = function(mjpegUrl, still_frames) { var self = this; if (!mjpegUrl) throw new Error('Please provide a source MJPEG URL'); self.mjpegOptions = url.parse(mjpegUrl); - - self.audienceResponses = []; - self.newAudienceResponses = []; - - self.boundary = null; - self.globalMjpegResponse = null; - - self.proxyRequest = function(req, res) { - - // There is already another client consuming the MJPEG response - if (self.audienceResponses.length > 0) { - self._newClient(req, res); - } else { - // Send source MJPEG request - var mjpegRequest = http.request(self.mjpegOptions, function(mjpegResponse) { - // console.log('request'); - self.globalMjpegResponse = mjpegResponse; - self.boundary = extractBoundary(mjpegResponse.headers['content-type']); - - self._newClient(req, res); - - var lastByte1 = null; - var lastByte2 = null; - - mjpegResponse.on('data', function(chunk) { - // Fix CRLF issue on iOS 6+: boundary should be preceded by CRLF. - if (lastByte1 != null && lastByte2 != null) { - var oldheader = '--' + self.boundary; - var p = chunk.indexOf(oldheader); // indexOf provided by buffertools - - if (p == 0 && !(lastByte2 == 0x0d && lastByte1 == 0x0a) || p > 1 && !(chunk[p - 2] == 0x0d && chunk[p - 1] == 0x0a)) { - var b1 = chunk.slice(0, p); - var b2 = new Buffer('\r\n--' + self.boundary); - var b3 = chunk.slice(p + oldheader.length); - chunk = Buffer.concat([b1, b2, b3]); - } - } - - lastByte1 = chunk[chunk.length - 1]; - lastByte2 = chunk[chunk.length - 2]; - - for (var i = self.audienceResponses.length; i--;) { - var res = self.audienceResponses[i]; - - // First time we push data... lets start at a boundary - if (self.newAudienceResponses.indexOf(res) >= 0) { - var p = chunk.indexOf('--' + self.boundary); // indexOf provided by buffertools - if (p >= 0) { - res.write(chunk.slice(p)); - self.newAudienceResponses.splice(self.newAudienceResponses.indexOf(res), 1); // remove from new - } - } else { - res.write(chunk); - } - } - }); - mjpegResponse.on('end', function () { - // console.log("...end"); - for (var i = self.audienceResponses.length; i--;) { - var res = self.audienceResponses[i]; - res.end(); - } - }); - mjpegResponse.on('close', function () { - // console.log("...close"); - }); - }); - - mjpegRequest.on('error', function(e) { - console.error('problem with request: ', e); - }); - mjpegRequest.end(); + self.still_frames = still_frames; + self.still_frame_idx = 0; + self.consumers = []; + self.boundary = 'ipcamera'; + self.on_air = true; + self.frames_missed = 50; + + self._handle_data = function(chunk) { + var p = chunk.indexOf('--' + self.boundary); + if (p >= 0) + self.frames_missed = 0; + + if (!self.on_air) + return; + + for (var i = self.consumers.length; i--;) { + var res = self.consumers[i]; + + if (res.is_live) { + res.write(chunk); + } else { + if (p >= 0) { + res.write(chunk.slice(p)); + res.is_live = true; + } + } } - } + }; - self._newClient = function(req, res) { + self._newClient = function(req, res){ res.writeHead(200, { 'Expires': 'Mon, 01 Jul 1980 00:00:00 GMT', 'Cache-Control': 'no-cache, no-store, must-revalidate', 'Pragma': 'no-cache', 'Content-Type': 'multipart/x-mixed-replace;boundary=' + self.boundary }); + res.is_live = false; - self.audienceResponses.push(res); - self.newAudienceResponses.push(res); + self.consumers.push(res); - req.socket.on('close', function () { - // console.log('exiting client!'); + req.socket.on('close', function() { + self.consumers.splice(self.consumers.indexOf(res), 1); + }); + }; - self.audienceResponses.splice(self.audienceResponses.indexOf(res), 1); - if (self.newAudienceResponses.indexOf(res) >= 0) { - self.newAudienceResponses.splice(self.newAudienceResponses.indexOf(res), 1); // remove from new - } + self.proxyRequest = function(req, res) { + self._newClient(req, res); + }; + + self._start_request = function() { + self.producer_response = null; + self.producer_request = http.request(self.mjpegOptions, function(response) { + self.producer_response = response; + self.boundary = extractBoundary(response.headers['content-type']); + + response.on('data', self._handle_data); + response.on('end', function() { + /* handle end of camera stream */ + }); - if (self.audienceResponses.length == 0) { - self.globalMjpegResponse.destroy(); - } + response.on('close', function() { + /* handle close of producer */ + }); }); - } + self.producer_request.on('error', function(e) { + console.log('Error on producer', e); + }); + self.producer_request.end() + }; + + self.frame_ticker_interval = 240; + self._frame_ticker = function() { + self.frames_missed += 1; + if (self.frames_missed > (1000 / self.frame_ticker_interval)) { + self.frames_missed = -(10000 / self.frame_ticker_interval); + + console.log("No frames received - restarting producer request."); + + if (self.producer_response) + self.producer_response.destroy(); + else if (self.producer_request) + self.producer_request.abort(); + self.producer_request = null; + self.producer_response = null; + self._start_request(); + } + + if (self.on_air && self.frames_missed >= 0) + return; + + self.still_frame_idx++; + if (self.still_frame_idx >= self.still_frames.length) + self.still_frame_idx = 0; + + var frame = self.still_frames[self.still_frame_idx]; + + var header = '\r\n--' + self.boundary + '\r\n'; + header += 'Content-Type: image/jpeg\r\n'; + header += 'Content-Length: ' + frame.length + '\r\n\r\n'; + + var buffer = Buffer.concat([ new Buffer(header), frame ]); + + for (var i = self.consumers.length; i--;) { + var res = self.consumers[i]; + + res.write(buffer); + res.is_live = true; + } + }; + self.frame_ticker_id = setInterval(self._frame_ticker, self.frame_ticker_interval); } |