ffmpeg jpeg stream to webm only creates a file .webm with 1 frame (snapshot) or empty .webm file (mjpeg)

Question

my problem is that when i try to turn a series of jpegs into a webm video. I either get a webm file with a single frame or a webm file with nothing in it (0 kb).

var fs = require('fs');
var path = require('path');

var outStream = fs.createWriteStream(__dirname+'/output.webm');
var ffmpeg = require('fluent-ffmpeg');

this one is a mjpeg stream URL. it produces a file with nothing.

//var proc = new ffmpeg({source:'http://xxx.xxx.xxx.xxx/goform/stream?cmd=get&channel=0',timeout:0})

this one is a snapshot URL. it produces a file with a single frame.

var proc = new ffmpeg({source:'http://xxx.xxx.xxx.xxx/snapshot/view0.jpg',timeout:0})

.fromFormat('mjpeg')
.size('2048x1536')
.toFormat('webm')
.withVideoBitrate('800k')
.withFps(20)

I have tried to use pipe instead but no dice :(

//.pipe(outStream,{end:false});
.writeToStream(outStream,{end:false})

any help is appreciated.

at this point i am up for using a basic shell command with exec but when i try that i just get errors also. Yes, it goes without saying I am a noob.

Side note:

I have tried things like zoneminder but it just breaks with our cameras and the number of cameras. so i am making a bare bones solution to record them. With our current cloud service we are missing very important moments and its costing more in energy and time.

Answer 1

thanks everyone that had a look and tried to figure it out :)

i have had some success with this method. It essentially works off a snapshot URL instead of the MJPEG. this uses request. but you could technically use anything since the method is using a pipe. image2pipe.

var spawn = require('child_process').spawn;
var request = require('request');
var args = '-f image2pipe -r 1 -vcodec mjpeg -i - -f webm -r 1 test3.webm';
var encoder = spawn('ffmpeg', args.split(' '));
encoder.stderr.pipe(process.stdout);
var interval = function(){
    request('http://xxx.xxx.xxx.xxx/snapshot/view0.jpg',function(er){
        if(er){console.log(er)}
        setTimeout(function(){interval()},1000)
    }).pipe(encoder.stdin,{end:false})
}
interval();

i could have used setInterval but i only wanted it to try again after it finished the request.

EDIT: it turns out my camera was down when i was trying to use the method in the initial questions so im not sure if it works... but i know this does for MJPEG

var spawn = require('child_process').spawn;
var args = '-f mjpeg -framerate 1 -i http://xxx.xxx.xxx.xxx/goform/stream?cmd=get&channel=0 -vcodec libvpx -framerate 1 -bitrate 256k video_file.webm -y';
console.log(args)
var encoder = spawn('ffmpeg', args.split(' '));
encoder.stderr.pipe(process.stdout);