Reduces Video Streaming Latency

galch commented 9 years ago

Challenge

real-time video streaming that has almost zero latency
Prerequisite
ubuntu 14.04 LTS on ODROID U3 or XU3
USB webcam
Setup Streaming Server
install libav(https://libav.org/) instead of ffmpeg
- # sudo apt-get install libav-tools
edit or make server configuration file and start server
- # sudo vi /etc/avserver.conf
- # avserver
start encoding and connect to streaming server
- # avconv -f video4linux2 -s hd480 -r 30 -i /dev/video0 http://localhost:8090/feed1.ffm

galch commented 9 years ago

setting

usb endoscope
internal network (192.168.0.x)
- laptop 2.4GHz wifi, ODROID 2.4GHz wifi
format : avi
encoder setting
- avconv -f video4linux2 -s vga -i /dev/video0 -vcodec mpeg1video -preset ultrafast http://localhost:5555/feed1.ffm

latency : 400ms

http://flash-clocks.com/free-flash-clocks-blog-topics/free-flash-clock-180.swf latency_20150321_endoscope_vga_mpeg1

galch commented 9 years ago

odroid U3 에서 gstreamer x264enc plugin 관련 버그, 패키지 설치해도 인식 못함.

avconv streaming server를 거치지 않고 udp로 바로 전송하는 방식으로 변경..

avconv -f video4linux2 -s vga -i /dev/video0 -c:v mpeg2video -f mpegts udp://192.168.0.2:5555

galch commented 9 years ago

gstreamer 1.4 에서 x264enc plugin을 발견하지 못할 때 apt-get install gstreamer1.0-plugins-ugly를 사용하여 해결.

정상 작동은 하는 것 같지만, streaming에서 not-negotiated 문제 발생. videotestsrc로 확인해야함

galch commented 9 years ago

gstreamer example for v4l2 http://www.z25.org/static/_rd_/videostreaming_intro_plab/

galch commented 9 years ago

changed setting

ffmpeg -> gstreamer
format : jpeg 640 x 480
odroid - router - pc
ODROID gst-launch-1.0 v4l2src ! video/x-raw,width=640,height=480 ! jpegenc ! rtpjpegpay ! udpsink host=IP_ADDRESS port=5200
Reciver gst-launch-1.0 udpsrc port=5200 ! application/x-rtp, encoding-name=JPEG,payload=26 ! rtpjpegdepay ! jpegdec ! autovideosink

640x480 latency : ~120ms

MJPEG supported webcam Ver.

ODROID gst-launch-1.0 v4l2src ! image/jpeg,width=1280,height=720 ! rtpjpegpay ! udpsink host=IP_ADDRESS port=5200
Reciver as same as before

1280x720 latency : ~120ms

TKoma commented 9 years ago

USB 연결 시 Latency 측정 HD-3000

usb-pc latency : ~ 80ms

default

internal network : 80 ~ 120ms

TKoma commented 9 years ago

Look for fastest video encoder with least lag to stream webcam streaming to ipad stackoverflow

http://stackoverflow.com/questions/12020430/look-for-fastest-video-encoder-with-least-lag-to-stream-webcam-streaming-to-ipad

TKoma commented 9 years ago

https://obsproject.com/forum/threads/webcam-latency-question-logitech-c910-c920.10517/

http://arstechnica.com/civis/viewtopic.php?f=6&t=1220783

galch commented 2 years ago

https://docs.aws.amazon.com/kinesis/index.html

galch commented 2 years ago

gst-launch-1.0 autovideosrc ! queue ! videoconvert ! video/x-raw,width=640,height=480,framerate=[30/1,10000000/333333] ! x264enc bframes=0 speed-preset=ultrafast bitrate=512 byte-stream=TRUE tune=zerolatency ! video/x-h264,stream-format=byte-stream,alignment=au,profile=baseline ! rtph264pay ! udpsink host=127.0.0.1 port=5000

gst-launch-1.0 udpsrc port=5000 caps = "application/x-rtp, media=video, clock-rate=90000, encoding-name=H264, payload=96" ! rtph264depay ! avdec_h264 ! autovideosink

GT-Robotics / odroid_vlink