How to get the MJPEG stream from a NC541 camera? - mjpeg

I have an NC541 IP camera, which supposedly does have an MJPEG stream, as in the manual it says "The video is compressed by MJPEG", but I can not find a way of how to get that stream from the camera. Seems that it wants to work only with the build-in program, while I need the way mjpeg stream instead.
Any ideas? Thanks!

I don't have this camera, but on many you can simply right click on the video window in your browser, select properties, and it will tell you the URL of the raw stream. If this is a multi codec camera you may or may not get the mjpeg stream depending on which one is chosen for the camera's home page. This often works for me.

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FFMPEG handling h264 stream that does not send a frame consistently

I am working with a raw h264 stream, this is a live stream coming from a device, however when the device is streaming a menu page that is static, it doesn’t send out a frame. I am feeding the stream back into a v4l2 loop back instance and then consuming this on a webpage via getUserMedia. The issue I have is that ffmpeg does not send frames to v4l2 when the hardware device is not sending frames. I have tried to set the output of ffmpeg to cfr and 60fps. However this doesn’t make it send out duplicates of the last frame. Is there anyway to achieve this?
Thanks in advance

How to play PES+H264 stream via ffmpeg/ffplay command

I have a h264 video stream wrapped as pes packets, while playing on my embedded hardware, the screen blurred.
So I want to verify the accuracy using ffmpeg command, but how, is anyone can help? that will be very appreciated.

DirectShow WAV file source does not produce any sound when graph runs

We have a DirectShow application where we capture video input from USB, multiplex with audio from a WAV file (backing music), overlay audio and video effects, compress and write to an MP4 file.
Originally we were using an audio input source (microphone) and mixing our backing music and sound effects over the top but the decision was made to not capture live audio, and so I thought it would make more sense to use the backing music WAV file itself as the audio source.
Here is the filter graph we have:
backing.wav is a simple WAV file (stored locally), and was added to the graph using IFilterGraph::AddSourceFilter.
The problem is that when the graph is run, no audio samples are delivered from the WAV file. The video part of the graph runs as normal, but it's as if the audio part of the graph simply isn't running.
If I stop the graph in GraphEdit, add the Default DirectSound Device audio renderer and hook that up in place of the AAC Encoder filter and then run the graph again, the audio plays as you would expect.
Additionally, if backing.wav is replaced with an audio capture source like a microphone, audio data flows through as normal.
Does anyone have any ideas why the above graph, using a WAV file as the audio source, would fail to produce any audio samples?
I suppose the title is incorrectly identifying/summarizing the problem. There is nothing to tell for the fact that audio is not produced. It is likely that it is produced equally well with DirectSound Renderer and with AAC Encoder, specifically the data is reaching output pin of Mixing Transform Filter (is this your filter? You should be able to trace its flow and see media samples passing though).
With the information given, I would say it's likely that custom AAC encoder somehow does not like the feed and somehow either drops data or switches to erroneous state. You should be able to debug this further by inserting a Sample Grabber (or alike) filter¹ before the AAC encoder and tracing the media samples. Also comparing them to data from another source. The encoder might be sensitive to small details like media sample duration or discontinuity flag on the first sample streamed.
¹ With GraphStudioNext (GraphEdit makes no longer sense compared to) you can use internal Analyzer Filter and review media sample flow interactively using filter property page.

Choose yuy2 or MJPEG in V4L

I am implementing a Camera Preview application. I am using V4L and until now I basically use this code> https://linuxtv.org/downloads/v4l-dvb-apis/capture-example.html
In this example, or any other example I found for that matter, I could not find a possibility to change the frame format to MJPEG to get a higher fps rate. Is there a way to tell V4L to use MJPEG instead of YUY2?
Found it, it is actually pretty simple. Just change the pixelformat in the format struct to V4L2_PIX_FMT_MJPEG.
So
format.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
becomes
format.fmt.pix.pixelformat = V4L2_PIX_FMT_MJPEG;

How to save video into Camera Roll

Can I use this code to save a recorded video in the Camera Roll?
Medialibrary.SavePictureToCameraRoll(fileName, Stream);
where Stream is photo stream or video stream.
You can't save videos in the camera roll from a third party application at the moment. That API can be used just to save pictures.
Apparently it is. Have you tried it yet?
A quick google's come up with this:
http://wp.qmatteoq.com/how-to-save-a-picture-captured-with-the-new-cameras-api-in-the-camera-roll-in-windows-phone-8/

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