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charliesteiner
05-10-2019, 01:36 PM
I just used a Tricaster Mini in a system that has 3 Panasonic PTZ cameras going through a managed switch in an auditorium. the run to the control room is about 150 ft. I added 2 cameras on the stage: 1 went via SDI and the other was a GoPro which went to an HDMI Spark and ran through the same switch as the PTZ cameras to the Mini. it showed up in the switcher right away, but it showed a clear latency compared to the other cameras - it was on the drummer so very easy to spot. I'm wondering why the Spark would cause a latency more than the cameras with built-in NDI. I used to send the drummer GoPro through an HDMI-SDI converter and that did not show latency.

kanep
05-10-2019, 02:10 PM
I'm assuming this is a Spark HDMI or SDI?

The Spark HDMI and SDI are NDI-HX, they cannot start compression of the signal until they receive it (which isn't until it comes out of the camera first). The NDI-HX built it PTZ cameras gives it a bit of head start over an external box since it is closer to the source signal. There is still time needed to get the sensor signal processed for SDI/HDMI output, which is why everything is much closer in sync directly off the PTZ camera. In the case of the Spark you care seeing the processing time in the camera and then the time in the Spark to turn it into NDI as well.

The new Spark Pro or soon to be released Spark Plus would be another solution, these units process NDI much faster (less than a frame). I have a video that shows the performance of the the Spark Pro (the Spark Plus would be the same).
https://www.newtek.com/blog/tips/newtek-connect-spark-and-spark-pro/

charliesteiner
05-10-2019, 03:13 PM
I'm assuming this is a Spark HDMI or SDI?

The Spark HDMI and SDI are NDI-HX, they cannot start compression of the signal until they receive it (which isn't until it comes out of the camera first). The NDI-HX built it PTZ cameras gives it a bit of head start over an external box since it is closer to the source signal. There is still time needed to get the sensor signal processed for SDI/HDMI output, which is why everything is much closer in sync directly off the PTZ camera. In the case of the Spark you care seeing the processing time in the camera and then the time in the Spark to turn it into NDI as well.

The new Spark Pro or soon to be released Spark Plus would be another solution, these units process NDI much faster (less than a frame). I have a video that shows the performance of the the Spark Pro (the Spark Plus would be the same).
https://www.newtek.com/blog/tips/newtek-connect-spark-and-spark-pro/

thanks.
any idea of the pricing on the Pro and Plus, and release dates?

kanep
05-10-2019, 03:59 PM
Spark Pro is available now, I think the Plus 4K is also available, the Plus (HD) should be out soon.
https://www.newtek.com/spark/#buy-now

geekazine
05-13-2019, 09:47 AM
I'm assuming this is a Spark HDMI or SDI?

The Spark HDMI and SDI are NDI-HX, they cannot start compression of the signal until they receive it (which isn't until it comes out of the camera first). The NDI-HX built it PTZ cameras gives it a bit of head start over an external box since it is closer to the source signal. There is still time needed to get the sensor signal processed for SDI/HDMI output, which is why everything is much closer in sync directly off the PTZ camera. In the case of the Spark you care seeing the processing time in the camera and then the time in the Spark to turn it into NDI as well.

The new Spark Pro or soon to be released Spark Plus would be another solution, these units process NDI much faster (less than a frame). I have a video that shows the performance of the the Spark Pro (the Spark Plus would be the same).
https://www.newtek.com/blog/tips/newtek-connect-spark-and-spark-pro/

I've always used my Spark as a Computer input option (Powerpoint for example). If there were any issues with latency or framerate, it wouldn't matter to a screen that changes every couple minutes. But recently, I've been using the Spark for video, and I have to admit, it's gotten worse from last year.

I was using it to bring in iPad, XBox, and other screens with 30-60 fps. Last year, they kept up. Now, I get larger delays of half a second or more. When I switch to the unit, I get up to a 1 second freeze as the signal starts back up. And of course, the skips.

I've been thinking of downgrading the firmware to test my theory.

Red Dog Records
05-13-2019, 12:34 PM
I've always used my Spark as a Computer input option (Powerpoint for example). If there were any issues with latency or framerate, it wouldn't matter to a screen that changes every couple minutes. But recently, I've been using the Spark for video, and I have to admit, it's gotten worse from last year.

I was using it to bring in iPad, XBox, and other screens with 30-60 fps. Last year, they kept up. Now, I get larger delays of half a second or more. When I switch to the unit, I get up to a 1 second freeze as the signal starts back up. And of course, the skips.

I've been thinking of downgrading the firmware to test my theory.

Are you also seeing a delay when switching to an NDI input?
We noticed that switching to SDI/internal sources is immediate, while any NDI input (including M/E with an NDI component) causes up to a 500ms delay in the switch. Some AE2 updates seemed to have minimized the delay, but it is still noticeable.
We have seen it with Spark (NDI HX) and with NDI running on a laptop. Have not tested this with our Bird-dog NDI Studio (Full NDI) yet.

Andrew

kanep
05-13-2019, 04:42 PM
I've always used my Spark as a Computer input option (Powerpoint for example). If there were any issues with latency or framerate, it wouldn't matter to a screen that changes every couple minutes. But recently, I've been using the Spark for video, and I have to admit, it's gotten worse from last year.

I was using it to bring in iPad, XBox, and other screens with 30-60 fps. Last year, they kept up. Now, I get larger delays of half a second or more. When I switch to the unit, I get up to a 1 second freeze as the signal starts back up. And of course, the skips.

I've been thinking of downgrading the firmware to test my theory.

I've been using the 1911 firmware on HDMI (and SDI) models since it has come out. I've not noticed any more latency that what I would say is normal. Are you wired or wireless? Wired should be well under half a second of latency. With WiFi, half a second is probably about right. Frame freezing or skipping is not normal, I always look to the network first, as that is the cause of the issue the majority of the times.

If you haven't, make sure you are up to date to the the latest NDI Tools, there has be constant work on the HX driver to improve its performance, if your HX driver is old, that might help.

PiD Media
05-13-2019, 09:10 PM
Latency on the Spark HX,... is no better or worse then an RTSP connected device.
We were using a pair of Sparks alongside RTSP based HDMI-to-IP boxes, and Hikvision IP cameras, to stream motorsports.
So long as we switched via what we saw on the screen, and not what was out the window, there was very little difference in lag between the NDI-HX sources and RTSP sources.
Whether that impacts other peoples productions depends on how fast you need to switch between changing subjects.

PiD Media
05-13-2019, 09:51 PM
Spark Pro is available now, I think the Plus 4K is also available, the Plus (HD) should be out soon.
https://www.newtek.com/spark/#buy-now

I wonder who's brain-fart it was to delete on-board recording from the SparkPro??? - it should have had a higher quality level of recording then the Spark HX.

The HDMI and SDI models should have had a 1/4-20 thread from the beginning.

loic CAREPROD
05-16-2019, 03:45 AM
I wonder who's brain-fart it was to delete on-board recording from the SparkPro??? - it should have had a higher quality level of recording then the Spark HX.

The HDMI and SDI models should have had a 1/4-20 thread from the beginning.

It is because of the FULL NDI process. Spar HDMI and SDI have h.264 encoders, easy to record that file on a disk. FULL NDI is around 20 times higher in term of bandwith. That means you should have an extra fast writing media slot to make it possible. Tha's why they neither are wifi capable.
According to the 1/4-20, you're absolutely right, and i'd like to see the poe too :)