Swedish mobile live streaming startup Bambuser released updated iOS and Android apps Thursday morning that offer, among other things, an interesting technology solution for mobile bandwidth constraints: The apps reduce the frame rate of a video stream during broadcast depending on current network throughput – and then only upload the dropped frames after a broadcast has ended.
Bambuser calls this “complement data” technology, and company CEO Jonas Vig told me that it was developed in-house. “Our proprietary streaming protocol adapts the frame rate in order to keep the video at a minimal latency,” Vig said, adding: “In order to not compromise the on-demand frame rate of the video, we developed the complement data technology to re-insert any frames that (weren’t) transmitted in real-time.”
Vig went on to explain that Bambuser doesn’t have a set minimim frame rate. Instead, when the frame rate drops too much compared to the original video, it simply suggests to shoot with a lower resolution. The apps also always prioritize audio. “A good flow and consistency in the audio is what the users often perceive as most important,” said Vig.
Optimizing the archived stream frames after a live stream has ended makes sense, considering that in many cases, the majority of users actually watch broadcasts after they’re over – something that Justin.tv recently paid tribute to with the launch and eventual spin-off of its Socialcam platform.
But restricting the upload to the dropped frames as opposed to re-uploading the entire file also is something that should make both mobile operators as well as end users who increasingly face bandwidth caps happy. Said Vig: “It’s significantly more efficient if you only have to patch, say, 15 to 25 percent of the frames to get a vastly improved viewing experience on demand, compared to having to upload a new version of the full video.”
He added that this approach will also take much less time, meaning that the full-quality version will be available sooner. (To learn more about challenges and opportunities of mobile bandwidth constraints, check out our Mobilize conference, happening next week in San Francisco.)
The new Bambuser apps will also offer a Google Maps mashup that will show where live streams are happening as well as an interesting take on live chat: Bambuser will replay past live chats synchronized with archived videos to give users a sense of what people were talking about when a live event unfolded.