Optimizing Video Settings for Mobile Viewing

[SB_Jim 1]

Last weekend I had my first opportunity to remote view using my iPod Touch from out of town. The streaming via Swann NVR to iPod was a bit less than smooth, and I'm wondering how I might improve on it? I believe that I had my sub-stream settings at reasonable levels (quality, etc.) The variables I am aware of re: network capability are:

 

1) My own DSL upload speed from home averages 650+ kb (no other useage or hit to bandwidth while I was away.

 

2) Very high speed wireless connection on my "receiving" end at the home I was visiting. Guessing that this would in no way be a choke point.

 

3) While using my iPod on my LAN I have great performance - as might be exected. Still Sub-stream.

 

Is there any advantage to setting the bitrate to Constant vs Variable?? I have 5 cams installed, and one more on the way.

 

From my in-camera (Swann bullet) menus:

 

[JoeyJoey 0]

I changed all my cameras to be constant, VLC plays the stored mp4 video well, with variable it had problems.

 

For the mobile viewing, I use either the Lorex App or the Hikvision 4500 app on Android. I have the sub stream max rate set to 512Kbps on my 1.4 Mbps upload.

I use this app to aim the cameras.

 

When changing the viewing quality on the app, this changes the quality setting in the camera via the nvr, balanced(sub), fluent(sub), clear(main stream), custom (sub or main).

 

So be careful when you change these, as you can change the main stream too, which affects the stream being recorded. I don't like how this works.

 

Your iframe number could be higher on the substream, 30 I think mine is.

Hope this helps.

[vector18 1]

You can try upgrading your ISP upload speed. DSL is a step below the latest broadband today. I like setting my cameras to constant. There's less processing going on IMO and the image looks the same quality all the time. And if your not watching

on an ipad or a tablet, you can lower the resolution. Remember your smart phone is like 3 inches.

[SB_Jim 1]

I've considered upping my service level. I'd still stay w/ DSL currently - since I currently have 3 down / 1 up, and I could go to something like 15 / 3 mbps w/out changing devices. But, before I do that I want to optimize my settings to see where that gets me.

 

I'm using the SwannNVR mobile app on my iPod (don't have a smart phone yet). In the app the resolution option (highest of the three, but still very modest) says 704 X 576 (CIF). In the camera menu the closest setting to that (and the one I've selected) is 704 X 480.

 

What is the I frame interval? I didn't select the "3" - it was there by default.

 

Regarding Variable vs Constant Bit Rate, wouldn't selecting Variable potentially put less demand on the NVR if it can "run itself" sufficiently at a lower than specified constant rate. Obviously I don't get this concept yet.

 

Thx for your ideas.

 

Jim

[JoeyJoey 0]

http://support.slingbox.com/get/KB-2000081.html has good info about the i frame. It is the full refresh frame, where the rest of the frames are the difference frames, its part of the compression scheme.

 

You can use this app too, people have said that it is better.

https://itunes.apple.com/us/app/ivms-4500-lite/id441697527?mt=8

 

I use the Android equivalent on the Lorex. It has more options than the swann app, check it out. The playback feature, scrolling through events is really good and smooth.

 

By going with constant, if you see it working, with all cameras in constant mode, you know it works. With variable, you don't know how it will act under different conditions, and when things don't work smoothly, it could be a reason why it isn't.

[SB_Jim 1]

http://support.slingbox.com/get/KB-2000081.html has good info about the i frame. It is the full refresh frame, where the rest of the frames are the difference frames, its part of the compression scheme.

 

You can use this app too, people have said that it is better.

https://itunes.apple.com/us/app/ivms-4500-lite/id441697527?mt=8

 

I use the Android equivalent on the Lorex. It has more options than the swann app, check it out. The playback feature, scrolling through events is really good and smooth.

 

By going with constant, if you see it working, with all cameras in constant mode, you know it works. With variable, you don't know how it will act under different conditions, and when things don't work smoothly, it could be a reason why it isn't.

 

Thx Joey - nice article on I-frames. In the article it says "When intervals between I-Frames are longer, the video transmission uses a lot less bandwidth, but the video quality is lower." So in my case, my Main Stream I Frame is set at 100, and the Sub Stream I Frame is set at 3.

 

How do I interpret this? Obviously the Main Stream is providing me maximum viewing resolution & quality when I'm at home on my LAN, but what does these setting imply? Are there 100 "actual full" frames of video streaming before an I-frame is displayed during Main Stream, and only 3 "actual full" frames of video streaming before an I-frame is displayed during Sub Stream?

 

Vector18 - did you mean to say that since many of us are streaming video to a small portable device (such as my iPod) - that having the resolution set higher than necessary is rather pointless since we're already viewing on a 3" screen - where it'll look decent anyways?

 

Jim

[vector18 1]

Yes, that is exactly what I was saying. By lowering the resolution, there is less data being processed by the ipod and on

that tiny screen, it wouldn't matter anyway so motion will look more fluent. You have nothing to lose by trying it out.

[dexterash 0]

Let your cameras on VBR and reduce the max bitrate to what you get out of /

[SB_Jim 1]

Okay, I'll set them to VBR. Can one of you really smart folks please give me the "short answer" to my previous question re: i_frame rate setting? Here's what I wrote in my last post:

 

"How do I interpret this? Obviously the Main Stream is providing me maximum viewing resolution & quality when I'm at home on my LAN, but what does these setting imply? Are there 100 "actual full" frames of video streaming before an I-frame is displayed during Main Stream, and only 3 "actual full" frames of video streaming before an I-frame is displayed during Sub Stream? This is in reference to the current cam settings of 100 / 3 for Main / Sub i-frames in my cams.

 

Vector18 - I believe that I did have my sub-stream and mobile app set at some reasonable low setting - hoping to get some fluidity to the video - even had a lower quality image. However, there were numerous times when the video "froze" for several seconds to 10-12 seconds of hesitation.

 

Thx,

 

Jim

[vector18 1]

IMO, vbr sounds like the right thing to do on paper, but when you log into a camera, and if there is no action, the image looks

very poor. I know it doesn't matter because nothing is going on anyway, but do you want to see a lesser quality image just

because there is no action going on? It's your choice, try it out, see what you think. As far as missing frames on a mobile device, I find they work best on wifi. I had an iphone 4s and would watch my cameras on 3G and they were ok. Than I upgraded to the 5 and if I'm on LTE, than I get even more fluidity. If I'm on fast wifi, the image boots right up and close to real time. So, keep in mind what is giving your mobile device internet, not just your DVR settings.

[SB_Jim 1]

As far as the Wifi goes, this past weekend I was on a home network (remote) that has a download speed of 30 Mbps. So I was in a great environment for testing. Unfortunately, I had lots of long pauses - much longer than I would like to have (anywhere from 2-12 seconds).

 

If my settings in both the sub-stream and mobile app are approximately correct - and I believe they are, perhaps it's an issue of the very low upload bandwidth from my home? My upload speed - as just tested via iPod right now - is 0.7 Mbps.

 

J.

[JoeyJoey 0]

See the attached pic for my settings.

 

The red settings do not change via the NVR, they are fixed once set in the camera.

 

The green settings can be changed by both the NVR and the mobile app.

 

So don't even bother setting anything besides the marked red settings in the sub stream, as the app will change those when you use it.

 

 

The i frame is decided upon by you, if you have a good connection, a high number is good.

I have 30 set for both streams, which means every 30 frames the camera sends a full image, between those it sends the differences only.

If you have a network problem and miss frames, then it could look choppy and garbled. The lower the number the faster network you need.

 

Did you try the Hikvision iVMS 4500 software? That will adjust to your network quality if you set the different settings.

Hope this helps.

[JoeyJoey 0]

Here are the default 3 settings for the Hikvision app, I find the balanced to work well and of course the fluent on my 1.0+ Mbps upload DSL.

 

When playing back stored video (motion alarm video etc), the visual quality is much better (but jumpy as it can't keep up) and that is defined in the settings in the NVR.

The motion settings have to be equal or worse than the continuous settings.

[vector18 1]

and I believe they are, perhaps it's an issue of the very low upload bandwidth from my home? My upload speed - as just tested via iPod right now - is 0.7 Mbps.

 

Thats what I had said at first.

[SB_Jim 1]

Let your cameras on VBR and reduce the max bitrate to what you get out of /

 

Thank you, dexterash. I have confirmed that my currend DSL upload is 0.7 maga-bits, so if that's equivalent to 700 kilobits, dividing by 5 cameras, I get 140 for a bit rate. Now, in my Swann mobile app the lowest "max" bit rate I can select is 768. Being that it says "max", is this a possible issue which may prevent fluid streaming of the SUB to my mobile device when I'm away from my LAN?

 

If I'm viewing by remote, then there will not be any other demand on my bandwidth (that I can think of) from other users or devices.

 

Thank you for your assistance.

 

PS - Joey - I'll reply separately. For now I'm trying to get a baseline performance by using the Swann NVR mobile app, and at a later date I'll give a try with another app. BTW, seems like you have a really high fps set for your sub-streams! Is the iVMS-4500 s/w a mobile app or a client s/w?

[JoeyJoey 0]

The Hikvision iVMS4500 is an app for Android/iOS, people on here have said its better than the Swann app.

 

It has varied frame rates, as the app changes those in the NVR, main stream and sub stream.

[SB_Jim 1]

Okay, How do YOU spell frustration?? Here I've learned what I believe might be some appropriate settings to tweak my cams (i-frame interval, etc.), and the settings dont stick once I log out of the cams and come back later!!!

 

Zik - are you still running the Swann NVR? Can you please check this? I'd set a specific "video quality" level, and 30 for my i-frame interval on both Main & Sub. I come back later and the Sub is set to an i-frame of 3! Arrrrrgh! Below is what resulted after setting Main to Constant - it forced the video quality to lowest and i-frame back to 3 from 30!

 

[JoeyJoey 0]

Okay, How do YOU spell frustration?? Here I've learned what I believe might be some appropriate settings to tweak my cams (i-frame interval, etc.), and the settings dont stick once I log out of the cams and come back later!!!

 

Zik - are you still running the Swann NVR? Can you please check this? I'd set a specific "video quality" level, and 30 for my i-frame interval on both Main & Sub. I come back later and the Sub is set to an i-frame of 3! Arrrrrgh! Below is what resulted after setting Main to Constant - it forced the video quality to lowest and i-frame back to 3 from 30!

 

The settings of constant, greys out the quality, as it doesn't apply. The quality is based on the bit rate you select yourself.

 

I have an issue with the NVR where sometimes you go to a setting, and it is wrong, you have to go to another page, then come back, then it looks right.

 

These settings in the camera are being configured by the NVR, it communicates often. The i frame is not set by the Lorex NVR though.

[zikronix 0]

I am still running the nvr. I havnt looked at the camera lately...ill check it out some time this week.