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• What are the size/second convertion rate that I can expect on compressed video

  30 juillet 2013, par Jonathan Thurft

  I am developing an app and I am quite hesitant on allowing my users to share videos.

  Mainly due the space that videos can take up in the server which adds a huge maintainance cost.

  I have been reading around and I can see that there are lots of different libraries that allow me to compress video on iOS to make it easy to share.

  After much researching I couldn't find any estimate on file size / second after compressed.)

  I was wondering if anyone could share their experience with what file size / second I could expect with your preferred library in a video quality setting that is reasonable for mobile (I guess medium).

• Using FFMPEG to convert .mov to mp4 with Blob Urls (NodeJS)

  31 juillet 2020, par Mick Marsden

  I'm trying to convert my .mov files to .mp4 in nodeJS. I'm using fluent-ffmpeg, and my users are capturing live video on their mobile phones that come in a variety of file formats. But the API I'm sending these files to only accepts .mp4. As these videos are being captured live, I am using blobs to capture them. I'm trying to convert it to .mp4, but fluent-ffmpeg does not recognize the blob:url format.

  


  Do I have to turn the blob into buffer first ? What should I be doing when trying to convert a blob's format ?

  


• Trying to grab video stream from a 802W device

  1er juin 2015, par brentil

  A group of us in the RC hobby forums had started trying to use a device called the 802W, it takes RCA in and then broadcasts it back out over a WiFi you connect to via an Android or iOS device. They’re typically used for backup camera addon systems for vehicles. We want to use it to do FPV (First Person Video/View) with using smartphones instead of buying more expensive FPV goggles.

  802W device example (plenty of clones online)

  http://www.amazon.com/Wireless-Backup-Camera-Transmitter-Android/dp/B00LJPTJSY

  The problem is you can only use their application WIFI_AVIN or WIFI_AVIN2 from the app stores to connect to it because they don’t publish the information about how to grab the stream data. We want to write our own apps that can use the stream to better show the information. We’ve tried using VLC to grab the stream from an Android phone or a Windows PC but we’ve had no success so far. I was hoping someone could look at the Wireshark outputs and might understand what they’re looking at better than I am. I "think" it’s a UDP multicast being broadcasted but I just don’t know enough to be sure. We’ve tried using VLC to connect to network streams directly on the device or from udp ://@ type addresses but I think part of the issue too might be we’re missing the file path of the stream file.

  Attempting to reverse engineer their code for learning purposes showed that ffmpeg is inside a compiled .so library which also seems to be where the actual connection code happens which we were unable to dig into.

  In the images 192.168.72.33 is my phone and 192.168.72.173 is the 802W device.

  Image of what I believe is a UDP broadcast of the video information.
  

  This is what the stream turns into when the device connects using the WIFI_AVIN application.