Stream any number of video/image sequences to any number of browser windows,
using opencv and boost::asio.
This could be used as the basis for a web browser based video stream viewer, powered by
opencv. Currently using multipart/x-mixed-replace of jpeg images.
See http://en.wikipedia.org/wiki/Motion_JPEG
Future goals include more sophisticated video streams, e.g. webm.
- boost >= 1.40
- opencv >= 2.2
- cmake >= 2.8
- optional ecto https://github.com/plasmodic/ecto
% git clone git://github.com/ethanrublee/streamer.git % cd streamer % mkdir build % cd build % cmake .. % make
% cd streamer % build/bin/httpserv 0.0.0.0 9090 1 . Visit: 0.0.0.0:9090/stream_0
Server is based off of http://www.boost.org/doc/libs/1_40_0/doc/html/boost_asio/examples.html#boost_asio.examples.http_server_3
Optional ecto cells and python bindings. https://github.com/plasmodic/ecto
main.cpp shows the server's use, generates a random color and streams it.
dir_reader.py demoes the servers use from ecto. see module.cpp for an ecto cell that uses the server.
The a GET or POST to the url /_all is used for listing all available streams, as a text file with each line containing a url path.:
% curl -X GET http://localhost:9090/_all /foobar /stream_0 /stream_1
Also supports a listing based on a regular expression, where the base expression is
_all<CUSTOM_REGEX>(.*), e.g.:
% curl -X GET http://localhost:9090/_all/stream_ /stream_0 /stream_1 % curl -X GET "http://localhost:9090/_all/(.*)bar" /foobar
POST may also be used:
%curl -X POST "http://localhost:9090/_all/(.*)bar" /foobar
A GET of a /foobar will recieve a 302 redirect:
% curl -vX GET "http://localhost:9090/foobar" * About to connect() to localhost port 9090 (#0) * Trying 127.0.0.1... connected * Connected to localhost (127.0.0.1) port 9090 (#0) > GET /foobar HTTP/1.1 > User-Agent: curl/7.21.3 (x86_64-pc-linux-gnu) libcurl/7.21.3 OpenSSL/0.9.8o zlib/1.2.3.4 libidn/1.18 > Host: localhost:9090 > Accept: */* > * HTTP 1.0, assume close after body < HTTP/1.0 302 Moved Temporarily < Location: _stream/foobar/1303455736 < * Closing connection #0
This redirect is meant to fool the browser into not caching the connection, and returns a unique URL per GET.
Each stream is found at /_stream/<STREAM_PATH>/(.*):
% curl -vX GET "http://localhost:9090/_stream/foobar/12323" > /dev/null
* About to connect() to localhost port 9090 (#0)
* Trying 127.0.0.1... connected
* Connected to localhost (127.0.0.1) port 9090 (#0)
> GET /_stream/foobar/12323 HTTP/1.1
> User-Agent: curl/7.21.3 (x86_64-pc-linux-gnu) libcurl/7.21.3 OpenSSL/0.9.8o zlib/1.2.3.4 libidn/1.18
> Host: localhost:9090
> Accept: */*
>
* HTTP 1.0, assume close after body
< HTTP/1.0 200 OK
< Connection: close
< Max-Age: 0
< Expires: 0
< Cache-Control: no-cache
< Pragma: no-cache
< Content-Type: multipart/x-mixed-replace; boundary=--BOUNDARYSTRING
<
{ [data not shown]
The server will also return any file that is relative to where the document
root given at startup, including auto resolving index.html...:
% curl -X GET "http://localhost:9090" <html> <head></head> <body> <h1>An http mjpeg streaming server based on boost::asio</h1> <a href="/_all">/_all</a> a listing of all streams. <br /> <img src="/stream_0" alt="A streaming jpeg."/> </body> </html>
Quick start:
#include <opencv2/core/core.hpp>
#include "mjpeg_server.hpp"
void doit()
{
using namespace http::server;
// Run server in background thread.
std::size_t num_threads = 8;
std::string doc_root = "./";
//this initializes the redirect behavor, and the /_all handlers
server_ptr s = init_streaming_server("0.0.0.0", "9090", doc_root, num_threads);
streamer_ptr stmr(new streamer);//a stream per image, you can register any number of these.
register_streamer(s, stmr2, "/stream_0");
s->start();
while (true)
{
cv::Mat image;
//fill image somehow here. from camera or something.
bool wait = false; //don't wait for there to be more than one webpage looking at us.
int quality = 75; //quality of jpeg compression [0,100]
int n_viewers = stmr->post_image(image,quality, wait);
//use boost sleep so that our loop doesn't go out of control.
boost::this_thread::sleep(boost::posix_time::milliseconds(33)); //30 FPS
}
}