10 second delay



  • Whats up with the 10 second delay on the camera stream? I understand that there may be a few seconds where your alexa device has to negotiate the video stream, but once it does, since the stream is connecting through the LAN, I don’t really understand why there is a 10 second time difference between what displays on my alexa device vs. what shows simultaneously on my NVR. Help me understand.



  • Hello, newbie here. I’ve only just registered today with a single ucam247 camera. I have also noticed this time lag. Does the bandwidth of the stream cause the lag? My set up is using a 1920 x 1080 image size. Should I reduce this and will it reduce the lag?



  • @Boluwd

    I don’t think the stream size is the problem as I’m streaming the sub stream from my NVR at 640x360 (main stream on my cameras is 4MP) plus there’s really no need for all that resolution on such a small screen. I’ve tried adjusting the resolution up and down and get the same result.



  • @LYNC-SmartHome like I said earlier, I’m new to this today. Is this lag normal or is it a recent issue?



  • @LYNC-SmartHome

    We typically see anywhere from a 5 to 15 second delay in the camera streams. Unfortunately lowering the resolution does not always have any significant impact to this delay. The delay time also seems to vary between camera manufacturers. For example the Dahua/Amcrest cameras seem to only lag 5-6 seconds while Hikvision and many others are 10-15.

    We believe there are two underlying issues in play. First, we have tested the streams using desktop computers using VLC and FFPLAY (FFMPEG) and see almost no delay. However when using these tools directly on lower powered ARM devices such as a Raspberry Pi, we do see some amount of latency. So I think the lower powered hardware and likely decoding capabilities of the Alexa devices are limited and causing most of the latency. Second we think the Alexa devices are also buffering a few seconds of the stream before beginning the playback to better handle small hiccups that might be encountered in normal playback.

    These are just observations … nothing confirmed with absolute certainly. In some cases, if the camera supports it, disabling the audio channel in the camera’s internal settings can help reduce some of the latency.

    Thanks, Robert



  • @LYNC-SmartHome
    In my experience, the bitrate should be set very high to fill up the stream-buffer sooner



  • @czandor

    Good tip, I’ll try this out today and see if I can get any noticeable improvement in the delay period.

    Thanks, Robert



  • I just set this up yesterday and the only thing I am a little disappointed in is the delay. I am running monocle gateway in a docker container on a NUC. I have three Amcrest cameras. Two are wired and one wireless. Delay is 7 to 10 seconds. I tested the streams using VLC and the result is immediate streaming so I had better hopes for monocle. However, even dealing with the delay I am very impressed with the service. Hopefully at some point the speed will improve. My goal is to have my firetv immediately display the door camera on all TV’s when someone rings the doorbell. However a 10 second delay is a bit long. Otherwise great product.



  • @jeckels

    Unfortunately the majority of the delay is with the Amazon device itself. The Monocle Gateway may add a second or two to the latency but the majority is with the device itself playing the RTSP streams. The best we have seen is about 5 seconds latency with most Amcrest and newer Dahua cameras on an Echo Show. Yes, your PC running VLC is a powerhouse compared to the Alexa devices and it runs with almost no latency. We have tested VLC on similar devices like Raspberry Pis and get similar results with 5-10 seconds of latency.

    Hopefully Amazon can improve this latency over time, but to date, I really have not noticed much improvement since day one.

    Thanks, Robert



  • Just adding my 2 cents worth (my first post)

    I just set up 3x DS-2CD2142FWD-IS and 1x DS-2CD2E20F from Hikvision. I have my Monocle gateway running on an RPI 3 over ethernet.

    I am using the sub stream at 640x360 on the big cameras and 704x480 on my little indoor camera

    rtsp://<ip>:<port>/Streaming/Channels/102/

    I am getting about 9s delay on the Amazon echo show 5 however… it is worth noting that I also purchased a cheapy Netvue (Alexa certified) camera for the baby room … and it too has 9s of delay while in it’s own app on my iPhone, there is less than half a second delay.

    Thank you so much for this product Mr/Ms Monocle inventor. I love it! Been looking for a product to mask IP cameras to any provider of “smart” screen. Homebridge style. I love it.



  • Just a question, is this related to the Monocle gateway requirement or does this lag exist on the older Show devices like the 2nd Gen show 10?

    I have only got the echo show 5 so I have nothing else to compare it to



  • I really like my UniFi cameras but the cameras themselves have a 3-5 second lag built in



  • @Leofr1cs

    The initial delay seems to be entirely based on the RTSP player and likely H.264 decoding built into the Alexa hardware devices. Some camera, mostly based on the Dahua hardware like Amcrest seem to only have around a 5 second delay while others often have closer to 10 second delays. In my testing using a high resolution versus a low resolution seemed to have little impact on improving this latency.

    I have also tested these types of RTSP streams using Raspberry Pi hardware and that too has similar stream startup latency – so I’m just guessing that a combination of the hardware and software codecs just perform better on full desktop/laptops versus the limited capacity of the low power ARM-based devices.

    So could it be further improved? Yes, I’m sure there is room for improvement in the optimization on these devices for RTSP streams and the supported video and audio codecs. Will Amazon improve it? Well, thats impossible to know – but there really has not been any significant improvement (that we have witnessed) in streaming performance and compatibility since the first release of the Echo Show Gen 1.

    PS. Does the Monocle Gateway add latency to the streaming. Well, possibly … but minimal. From what we have seen in testing it does not add any more than 1 second to the streaming latency. Of course it could be worse in sub-optimal network conditions.

    Thanks, Robert


Log in to reply