var spawn   = require('child_process').spawn;
function sendGif() {
let ffmpegCommand = '-y -i http://192.168.88.247/mjpg/video.mjpg -t 0:00:10 -f mp4 -vcodec libx264 -pix_fmt yuvj420p -an -s 640x480 -r 1 /tmp/out1.mp4';
// let ffmpegCommand = '-y -i http://192.168.88.247/mjpg/video.mjpg -t 0:00:10 -f mp4 -vcodec libx264 -pix_fmt yuvj420p -an -s 640x480 -r 2 /tmp/out1.mp4';
let ffmpeg = spawn('ffmpeg', (ffmpegCommand).split(' '), {});
 ffmpeg.on('close', function(code) {
 sendTo('telegram.0', '/tmp/out1.mp4');
 });
};

function sendGif2() {
let ffmpegCommand = '-y -i rtsp://192.168.88.250:556/user=admin&password=ххххххх&channel=1&stream=0.sdp -t 0:00:10 -f mp4 -vcodec libx264 -pix_fmt yuvj420p -an -s 800x600 -r 1 /tmp/out.mp4';
let ffmpeg = spawn('ffmpeg', (ffmpegCommand).split(' '), {});
 ffmpeg.on('close', function(code) {
 sendTo('telegram.0', '/tmp/out.mp4');
 });
};

вбить в поиск #script, и посмтреть что уже было