I am wondering if it would be possible to merge two videos (side by side) without transcoding. The streams are identical except the pictures are different. Think IP cameras on a LAN.
I am on a platform where I dont have compute power for real transcoding.
The codecs I am interested in is h264 and h265.
I am thinking something a long the lines of:
modify size of video plane of video A.
add data from video B to video A while adding offsets.
If you know of projects that has done this I would appreciate a pointer.
kind regards
jesper
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I've put together a movie in Final Cut Pro 10.2.3 with a lot of edits cut to the beat of the audio track. It is synced perfectly when previewed within FCPX but is off by quite a bit after sharing regardless of what settings I choose. I've transcoded all my media and created optimized versions
If you are experiencing a sync problems with FCP, 95% of the time it is because of mixing audio sample rates. Final Cut Pro is having a difficulties in resolving them to match.
Firstly, verify that every audio clip within your Browser has exactly the same sample rate. A bad sign, is if you see a sample rate that is very close to 48,000 Hz, but it's not (for instance 47.998 Hz). Your best friends for preparing audio for sample-precision editing are Apple Logic or discontinued Soundtrack Pro 3.
Secondly, if you have multiple audio formats, transcode them to *.wav.
And only then edit.
I was doing some research on Live Streaming. I want to develop a solution where I will collect live streams from multiple remote cameras on my website, modify the stream with a custom text banner (i.e. we have on news TV channel, football match) at the bottom and broadcast it to all.
I know there are Flash plugins available for video streaming and editing, but I want to build this web app to be mobile friendly and responsive.
HTML5 could be used to display multiple video streams on the website, but how can I add a text banner, graphs or any other frame on a running live stream?
The easiest way to do this, and the way that gives you the most quality and control over presentation, is to just do it on the client application. It sounds like you control this, so just modify your application to fetch a data stream alongside the video stream. This will work great assuming that you control the client side, and exact synchronization isn't critical.
Assuming you don't control the players at all and you need to bake this all into the video, there are a variety of tools you can use. GStreamer, FFmpeg, even VLC depending on your requirements. If you need something more interactive, OBS might be something to look into as well.
The scenario: A guy walks along a route, through the crowd at a pool party.
The camera setup, is a customised rig with an array of GoPro's covering 360 degrees of rotation.
The end result needs to be a video that'll let the user
click & drag the video to change his viewpoint on the video. So for eg, he can turn the angle to behind him, and will see where the guy has walked from. Or he can look sideways as he walks. (Likely some up/down movement too)
pause playback
zoom in/out
So for eg, you spot a hot girl in the crowd. You'd pause, zoom in and then play the video watching her as the guy walks past her.
How could this be achieved with HTML5 (non-Flash) methods?
I don't even know what technologies would be required to achieve something like this, so I'm hoping that someone with a bit of experience in something similar could give me some pointers as to required
coding languages
server technologies
bandwidth considerations
etc
Thanks for your help!
(ps: this is a paid client job. so if you can do exactly this, lets talk about a quote?)
You'd be attempting something quite state-of-the-art.
The way I'd experiment with is to stream a video to the client and display it using WebGL, which the client can then manipulate without latency.
http://riaconnection.wordpress.com/2011/11/03/testing-live-video-streaming-to-webgl-and-html5-video-tag/
One way might be to stream 6 feeds - top, bottom, left, right, back front. These would be pre-processed so when displayed as a cube viewed from the center of the cube, the perspectives are corrected.
If the client can zoom in and out, then that means you'll need higher resolution stream. Six of them would mean very large bandwidth. You'll have to decide on a trade-off between bandwidth, quality and latency. If the client zooms in and changes pan / tilt, you could trade off latency and get better quality and bandwidth, but at the cost of higher server resource requirements.
There are plenty of video processing libraries for PHP, which would probably be my choice of server, but I'm biased.
Is it possible to generate multiple thumbnails from a FLV using only as3? The flv is on the same server as the swf so I'm not using any dedicated streaming server. I'd imagine that as long as the flv has load the video you'd be able to pull bitmapdata from a specific time of the flv.
My idea is to pull around 8 images from every flv, convert them to buttons and use them as links to specific chapters in the flv.
If this is not possible, would it work better with a dedicated streaming server like red5?
Edit:
I'd also like to know how to do it if it's possible :)
The idea is to not use the server.
The thumbnails will only be used within the swif, so no saving to another location.
You can do this in AS3 as long as you're actually playing the video within Flash. While playing when you seek to the desired frame capture a bitmap. If you want to save the bitmap for later use you need server-side code to store it.
Streaming vs http download will not make this problem any easier or harder (although with a streaming server you can seek to the desired point without having to download the whole flv to that point).
This would be much better done on the server. You'll need an app that can extract an image from an FLV. ffmpeg can do it.
I know it is possible to get mplayer to output stills from an FLV (though might need a bit of fiddling to get the time reference right), and these in turn can be stuffed into ImageMagick to resize into thumbnails. Not best solution, but probably easier than digging around as3's API.
video thumbnailer is a good idea.
http://blog.chrometaphore.com/2010/03/26/how-to-create-video-thumbnails-runtime-in-pure-actionscript-3-0-videothumbnailer/
I'm looking for a simple way to put up musical "tunes" on a website.
So here's an analogy to explain my question:
Let's say I want to put up a couple of big triangles as a picture on my web page. I can either draw a bitmap and save as GIF/JPG/PNG, put it up somewhere on the internet, and link to it with an element. That works but the larger the picture the more space my image file takes up.
Alternatively, I can use SVG (even though Internet Explorer support is lacking, grr) and use vector graphics which uses very little bandwidth regardless of image size.
In the music world, I can use WAV or MP3 files. Works great -- but if I just want to publish a 1-minute song of simple notes, by knowing the durations & pitches, & don't care that it sounds 100% exactly like a piano or accordion, is there a way to (a) create a file with the song, and (b) put it online in a format that is space-efficient? 1 minute of MP3 usually takes up hundreds of kilobytes.
You could use a MIDI file, this stores durations/pitches etc. as you suggest. You should be able to easily find software to create this type of file. However you will probably find the results sound terrible, as it is very dependent on the synthesiser hardware/software that is available on the end-user's machine.
For what you need this might be reasonable though.
Look into playing music files on websites using Flash.
You can control the Flash through JavaScript calls.
This is currently the "recommended" way to play small audio clips in a website.
For larger media files, look into streaming FLV files using a Flash player.
Hope this helps :)
Check out the MIDI format for instruments.
http://en.wikipedia.org/wiki/MIDI