> > Thanks for that clarification. Unfortunately the http server is a third > party camera that broadcasts a WiFi hotspot. Therefore we don't really > have control over the underlying server. However, what I do know is > that the ffmpeg command I quoted previously seems to be able to > grab a chunk of a video anywhere in the file without downloading the > whole thing. So I assume libav must also be capable. > The nginx module we develop https://github.com/kaltura/nginx-vod-module has the capability to efficiently clip MP4 files - 1. It downloads the index (moov atom) whether it's in the beginning of the file or at its end 2. It generates a new 'clipped' index for the output video 3. It determines the relevant range of the video/audio frames in the original file, and serves it to the client
In addition, this module has the ability to work in remote mode - it can pull the relevant sections of the file using HTTP range requests. So, easiest solution, assuming you can set up some server (and you don't have to provide a client-only solution) would be to set up such a "clipping proxy" and have the mobile app simply download the clip from the proxy (providing the clipping from/to offsets) If a server solution is not option, you can still use our code as a reference for the implementation. Btw, nginx has a built-in module for clipping MP4 files - http://nginx.org/en/docs/http/ngx_http_mp4_module.html But our module has several advantages compared to built-in version, incl: 1. Support for remote (HTTP) MP4 files 2. Support for MP4 files in which the index is at the end of the file Hope this helps Eran _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
