I have an iPad app which has a white board. what ever we write/draw anything over there.
Whatever I do on the app, should be viewable from some website (Live streaming).
Is there any library available to get above task.
I would recommend not to use HLS and instead send only delta updates. I expect that your whiteboard is mostly static, and using h.264 video compression doesn't really make sense in that case. It will reduce the image quality and take a very large amount of bandwidth.
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My javafx application has 6 small windows and one large one. Each plays hls using VLCJ.
From time to time the picture freezes on some windows, so I want to somehow reduce the consumption of players on the PC.
How can i do this?
In 6 small windows, I don't need sound, if I can turn it off with a parameter, will it affect memory or CPU consumption?
At the moment, I remove the sound there with --aout=directsound and the mute() function, but perhaps the audio is still processed by the players and the consumption is not reduced.
Since these are small windows, high quality content does not need to be displayed there. Is it possible to reduce the quality of the content using the player? Can this help and how to do it?
Tried using the :adaptive-logic=highest playback parameter, but it didn't help, most likely because the content has only one high quality.
Parameters for the player are here: https://wiki.videolan.org/VLC_command-line_help/.
But there are a lot of them and I do not understand how they work, so I ask for help.
Maybe I can skip some frames, which will not be very noticeable, but can help?
Update:
Now I'm trying these options, but I don't notice much change...
--no-audio
--postproc-q=1
--ffmpeg-hw
--avcodec-skip-frame=1
--avcodec-skip-idct=1
--avcodec-skiploopfilter=1
--avcodec-hw=any
--sout-avcodec-hurry-up
--no-sout-avcodec-interlace-me
I am building an app that streams video content, something like TikTok. So you can swipe videos in table, and when new cell becomes visible the video starts playing. And it works great, except when you compare it to TikTok or Instagram or ect. My video starts streaming pretty fast but not always, it is very sensible to network quality, and sometimes even when network is great it still buffering too long. When comparing to TikTok, Instagram ... in same conditions they don't seam to have that problem. I am using JWPlayer as video hosting service, and AVPlayer as player. I am also doing async preload of assets before assigning them to PlayerItem. So my question is what else can I do to speed up video start. Do I need to do some special video preparations before uploading it to streaming service. (also I stream m3U8 files). Is there some set of presets that enables optimum streaming quality and start speed. Thanks in advance.
So theres a few things you can do.
HLS is apples preferred method of streaming to an apple device. So try to get that as much as possible for iOS devices.
The best practices when it comes to mobile streaming is offering multiple resolutions. The trick is to start with the lowest resolution available to get the video started. Then switch to a higher resolution once the speed is determined to be capable of higher resolutions. Generally this can be done quickly that the user doesn't really notice. YouTube is the best example of this tactic. HLS automatically does this, not sure about m3U8.
Assuming you are offering a UICollectionView or UITableView, try to start low resolution streams of every video on the screen in the background every time the scrolling stops. Not only does this allow you to do some cool preview stuff based off the buffer but when they click on it the video is already established. If thats too slow try just the middle video.
Edit the video in the background before upload to only be at the max resolution you expected it to be played at. There is no 4k resolution screen resolutions on any iOS device and probably never will be so cut down the amount of data.
Without getting more specifics this is all I got for now. Hope I understood your question correctly. Good luck!
I am recording videos and playing them back using AVFoundation. Everything is perfect except the hissing which is there in the whole video. You can hear this hissing in every video captured from any iPad. Even videos captured from Apple's inbuilt camera app has it.
To hear it clearly, you can record a video in a place as quiet as possible without speaking anything. It can be very easily detected through headphones and keeping volume to maximum.
After researching, I found out that this hissing is made by preamplifier of the device and cannot be avoided while recording.
Only possible solution is to remove it during post processing of audio. Low frequency noise can be removed by implementing low pass filter and noise gates. There are applications and software like Adobe Audition which can perform this operation. This video shows how it is achieved using Adobe Audition.
I have searched Apple docs and found nothing which can achieve this directly. So I want to know if there exists any library, api or open source project which can perform this operation. If not, then how can I start going in right direction because it does looks like a complex task.
I just recently talked to an app marketing agency and they are strongly recommending that I find a way to take my 153MB app and somehow get it under the 50MB mark that is the current standard for downloading over a wireless network (3G, 4G, etc.).
I have no idea where to go from here. As far as app size goes, my app is very UI intensive and I have a combination of (mostly) JPGs, PNG's, and a few small videos. I've already run all my jpg's through JPEGmini and as many png's as still looked alright through tinypng.org.
I'm curious if I could somehow "compress" or zip my resources and then unzip them in code to significantly reduce my app size (Before it's installed on the device...I don't care how big it expands to after it's downloaded and installed).
Host the video somewhere else and then downloading them after the app starts for the 1st time (or when they are actually played) maybe the biggest win. Other small wins would be drawing procedurally as oppose to using images. What is the combined size of your images, also the combined size of your videos?
I have tried to google a lot but it seems like no one have done it beforein iOS.
My issue is: my server only allow the client to upload the video / audio / image file with limited size (e.g: 30M for video, 1M for audio). With that limit, I want to figure how much time the users are allow to record audio / video. This calculation must consider the difference devices for example the iPad 3 has better camera then ipad 2 so we will have less time to record the video.
I am wondering if we can programmatically calculate the time limit base on the known file size.
Thanks,
Luan.
When working with large amounts of data such as video and audio, compression should play a part in your calculation.
Compression results can vary greatly depending on what you are recording and as a result it would be unrealistic to try to forecast a certain maximum duration.
I can think of two options:
Predetermine very restrictive recording times per device (I believe it is possible in iOS to tell an iPad3 from an iPad2)
Figure out a way to re-encode a smaller part of the video until it is within limits.
Best of luck!
Cantgetright has the reason this is hard described perfectly.
What you really care about is megapixels of the camera (definition), worst case storage size of one second of video, and how many free megs are on the phone as well.
If you know most of these elements, time can be the constraint by which you determine the last one.
Always overestimate size to guarantee it'll work no matter what. People don't know how big 5secs of video is on their iDevices anyway so you can be stingy with allotted time