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Lightbridge compression/bit rate ?
579 21 2017-4-4 07:54:35
elmago
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[size=14.666666984558105px]Hi:
[size=14.666666984558105px]We took our Inspire 2 to a test to find out how it performed as a live feed to an OB truck. We made it via an HDMI-SDI converter an tried sending 1080 50i and 720 50P to the truck. The engineers in charge were amazed about the stability and kind of shots that could be achieved, but said that the signal was "unacceptable" to broadcast live. They said they usually work with a bitrate of 1 to 1.5 Mb/s in wireless videolinks, and the Inspire 2 was "clearly under 0.5 Mb/s"...
[size=14.666666984558105px]Anyone has a clue regarding bitrates, compression and how to improve it? the "broadcast" mode was enabled. You could see some kind of "refresh" of the video signal every two seconds as a vertical scan from top to bottom that gave some weird aspect to the images. We tried a couple of connection alternatives, even switched converters, but never looked better.[size=14.666666984558105px]We´re using the Inspire 2 with the latest firmware. We are intending to use lightbridge integrated system.  It seems that the system is unusable for live broadcast (at least with a decent quality). T[size=14.666666984558105px]hat would defeat the entire purpose of the system.
[size=14.666666984558105px]Best regards

2017-4-4 07:54:35
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allanart
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Broadcast quality live links are the domain of professional systems and well beyond the scope of the Inspire 2. The integrated Live Link is intended for low resolution viewing applications such as FaceBook Live. Its useful for fun and perhaps for remote client viewing, but definitely not professional broadcast quality..
2017-4-4 08:32:07
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elmago
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HI, Allan,  I disagree. One of the selling points of this equipment is the possibility of live broadcast in 1080p, 50fps or 720p, 60fps for professional porpouse . In fact DJI announces that.
I´m just expecting to see a feed that seems aceptable in 720, but the poor bitrate make an awful image whit a gross horizontal line refreshing the image.
2017-4-4 09:23:40
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I 2 Fly
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WOW... I also understood that the I2 would broadcast / downlink to a commercial broadcaster...  This was one of the selling points DJI had on the I2....  Can DJI clear this up please??
2017-4-5 03:02:58
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Amadeusz
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Do you have any screenshots of the footage ???  I am pretty surprised  that you cannot stream the decent 1080 50 fps quality footage...
2017-4-5 04:34:13
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Mike-the-cat
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This strikes me as a strange post. So let me put it in different words. You go buy a jacket. It looks good. Everyone thinks so too. Then a tailor comes around and says that this cannot be used in a business setting because the thread count is not to 'spec'.

Does pixel count / stream rate / some technical parameter trump content?

More people watch sports events on phones / tablets than ever before and from so many more varied locations than if they had to be in front of a TV. If you were watching a world cup match when you are on vacation, say on a beach or hotel, is not simply catching the angles and visuals worth something special?

What do others thinK?
2017-4-5 20:54:09
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Gybo102
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Mike-the-cat Posted at 2017-4-5 20:54
This strikes me as a strange post. So let me put it in different words. You go buy a jacket. It looks good. Everyone thinks so too. Then a tailor comes around and says that this cannot be used in a business setting because the thread count is not to 'spec'.

Does pixel count / stream rate / some technical parameter trump content?

I understand what you are getting at, but Im assuming the "engineers" working the equipment are looking for a bitrate / quality to match everything else they are working with (other live feeds ect)... being perfectionist in the job they do.

Either way, did you have the transmit settings in auto or manual? If you have it in manual, you can set your bit rate. I do not know what the algorithm is in auto, does it favor quality with provided good signal strength... or always favor signal integrity?

So try again with it in manual, and set bit rate to max and see what they say... pls update us as well
GL
2017-4-5 21:19:51
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Mike-the-cat
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Gybo102 Posted at 2017-4-5 21:19
I understand what you are getting at, but Im assuming the "engineers" working the equipment are looking for a bitrate / quality to match everything else they are working with (other live feeds ect)... being perfectionist in the job they do.

Either way, did you have the transmit settings in auto or manual? If you have it in manual, you can set your bit rate. I do not know what the algorithm is in auto, does it favor quality with provided good signal strength... or always favor signal integrity?

Good points.

Lets hear from the OP...
2017-4-5 21:47:39
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elmago
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Gybo102 Posted at 2017-4-5 21:19
I understand what you are getting at, but Im assuming the "engineers" working the equipment are looking for a bitrate / quality to match everything else they are working with (other live feeds ect)... being perfectionist in the job they do.

Either way, did you have the transmit settings in auto or manual? If you have it in manual, you can set your bit rate. I do not know what the algorithm is in auto, does it favor quality with provided good signal strength... or always favor signal integrity?

Hi Gybo, I repeat test at home today, and is the same problem.
we talk about the IMAGE TRANSMISSION SETTINGS
CHANNEL MODE (CUSTOM)
CHANNEL SELECTED ( I SELECT THE BEST ABOUT RECEPTION BY TRY WHIT ALL)
TRANSMISSION QUALITY ( 10MBPS)
FREQUENCY (BOTH 2.4 AND 5.8)
OF COURSE BRODCAST MODE ON

Must I say I tried whit all channels, in both frequencys, and even whit less transmission quality (8, 6, 4mbps )
I test to be near and far of the bird and no matter what I do is always the same refresh.
We test it whit a OB truck in a fist line broadcast company, at studio and today at home. And same problem appears.
I copy a link to some seconds of video recorded whit iphone 6 in my hand to a full HD tv at my home. (sorry about pour resources, I know it deserves a better way to demonstrate what I´m trying to explain)
I´ll try to get the file of the test make on the OB truck.
But meanwhile if some of you can make the same test whit the feed we can say if its a whole system problem whit the feed or its just a fail in my equipment.

https://www.dropbox.com/s/z7usry ... 0feed%20I2.mov?dl=0

2017-4-6 07:19:38
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elmago
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elmago Posted at 2017-4-6 07:19
Hi Gybo, I repeat test at home today, and is the same problem.
we talk about the IMAGE TRANSMISSION SETTINGS
CHANNEL MODE (CUSTOM)

forget the link its not useful, the refresh line desapear in the dropbox compression
2017-4-6 07:22:05
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Gybo102
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elmago Posted at 2017-4-6 07:19
Hi Gybo, I repeat test at home today, and is the same problem.
we talk about the IMAGE TRANSMISSION SETTINGS
CHANNEL MODE (CUSTOM)

dang, sorry to hear, DJI any input on the situation?
2017-4-6 11:08:48
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PSlats
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I'm wondering if Broadcast mode affects the output from the HDMI.

I understand that Broadcast mode is for Facebook streaming - not HD TV productions.

I think that has to be off to get 1080i at a high bitrate out of the HDMI output.

Can someone confirm ?

https://www.youtube.com/watch?v=pbFFOnNJPvQ

Light bridge 2 should be full res high bite rate at a quality broadcasters want ( to match other cameras)
2017-4-20 20:57:52
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PSlats
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I'm really surprised noone can answer this one!
2017-4-22 04:44:02
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allanart
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Hi folks. I have not tried to use either the Broadcast Mode or the HDMI output seriously, but I have had a play with it using my TV as a monitor (with HDMI input).
First, I think there may be some confusion here about "Broadcast Mode" and the "HDMI Output". My understanding is that the Broadcast Mode is intended for Live Streaming to FaceBook Live (or other such Social Network). The bit rate is likely to be low and the quality certainly not good enough for professional broadcast. The HDMI Output (on the RC) is a different matter, its completely independent of Broadcast Mode and provides a Live (almost real-time) HDMI output from the camera. There are two settings; "Picture in Picture" (shows both the main camera and the FPV camera) and the so called "Photo Image Transmission" which gives a clean feed. I tested the Photo Image Transmission mode on my TV (via HDMI) using all of the supported video resolutions and while I was not able to measure the video data-rate, they all appeared to be pretty good. I did notice some low frequency noise on the picture, but this may well be local interference  as it was done indoors. I have no idea why its  called "Photo Image Transmission" mode as its clearly live video! The other thing to consider is the quality of the HDMI to SDI converter used in the original test (Post #1) as all such things are not born equal!  

Hope this helps!
Allan
2017-4-22 08:22:52
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PSlats
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Thanks Allan - can anyone from DJI clarify?
2017-4-22 17:53:32
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Live Tv
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allanart Posted at 2017-4-22 08:22
Hi folks. I have not tried to use either the Broadcast Mode or the HDMI output seriously, but I have had a play with it using my TV as a monitor (with HDMI input).
First, I think there may be some confusion here about "Broadcast Mode" and the "HDMI Output". My understanding is that the Broadcast Mode is intended for Live Streaming to FaceBook Live (or other such Social Network). The bit rate is likely to be low and the quality certainly not good enough for professional broadcast. The HDMI Output (on the RC) is a different matter, its completely independent of Broadcast Mode and provides a Live (almost real-time) HDMI output from the camera. There are two settings; "Picture in Picture" (shows both the main camera and the FPV camera) and the so called "Photo Image Transmission" which gives a clean feed. I tested the Photo Image Transmission mode on my TV (via HDMI) using all of the supported video resolutions and while I was not able to measure the video data-rate, they all appeared to be pretty good. I did notice some low frequency noise on the picture, but this may well be local interference  as it was done indoors. I have no idea why its  called "Photo Image Transmission" mode as its clearly live video! The other thing to consider is the quality of the HDMI to SDI converter used in the original test (Post #1) as all such things are not born equal!  

The IS2 has a dedicated "Broadcast Mode" that outputs 1080i 50 or 720p60 at a higher data rate for broadcast use via the HDMI  ,  The other broadcast mode uses the app to stream direct to social media this is different and isn't associated  with the quality of HDMI output ..

I also have the same issue out of the HDMI and  it's even there when not in broadcast mode ,  if DJI could sort this that would be great as that was the selling point of the IS2 over the Phantom 4 Pro  , with a number of use all having the same issue it should be easy to replicate and sort out ...
2017-4-23 17:47:47
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PSlats
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When 'Broadcast more' is on it reduces the options of HDMI output formats as far as I can tell.
2017-4-23 17:57:44
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Live Tv
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With the release of the new DJI Cedence controller at NAB2017 with the broadcast standard SDI output , surely the rolling screen refresh isn't what they want the customers to experience as normal operation , especially if they are heavily pitching the IS2 to broadcasters (which is what NAB is all about )  , any TV engineer at NAB seeing this would certainly say it' not good for broadcast ...   DJI any ideas ?
2017-4-25 19:08:38
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elomda
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ive got a very similar issue, horizontal line scanning down my video image, looks like a refresh line. anyone know if there is a fix for this issue?
2017-7-13 21:51:17
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elomda
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link to video showing issue

2017-7-13 21:51:12
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Ale Reynoso Cin
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elomda Posted at 2017-7-13 21:51
link to video showing issue

https://www.youtube.com/watch?v=ftnkRA-LyQw

Same here
weeks waiting for a DJI answer (our DJI opened a case weeks ago)

https://forum.dji.com/thread-101572-1-1.html
2017-7-14 06:47:44
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Ale Reynoso Cin
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Ale Reynoso Cin Posted at 2017-7-14 06:47
Same here
weeks waiting for a DJI answer (our DJI opened a case weeks ago)
https://vimeo.com/222909158

So nobody from DJI can give some words about this?
Is it a bug? Several i2 owners swear they do not have this issue
Is it a design flaw? Can´t you do it a little bit less obvious? You can notice the issue from a mile.
Our DJI dealer opened a case but they haven´t received a word from you in weeks
Lost a big job opportunity because the image was "unusable" for OB broadcast...
2017-7-15 22:15:15
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