WIPVideo » History » Revision 15
Revision 14 (Saúl Ibarra Corretgé, 09/10/2013 10:32 AM) → Revision 15/43 (Saúl Ibarra Corretgé, 09/10/2013 10:40 AM)
h1. WIPVideo Notes while video is a work in progress. Repository: http://devel.ag-projects.com/cgi-bin/darcsweb.cgi?r=saul/python-sipsimple-video;a=summary h2. Dependencies The following dependencies are required to build PJSIP with video support (including H264) * SDL 2 * ffmpeg (libavformat, libswscale, libavcodec, libavutil) * libx264 Versions I have tried: * SDL (2.0.0-7655) * ffmpeg (2.0 release) * libx264 (snapshot-20130806-2245-stable) h2. Patches -If the above versions are used, PJSIP needs to be patched with the attached patch (avcodec.diff) or it won't compile. This does not occur when compiling it against the latest library versions on Debian unstable.- No longer needed. h2. Compiling dependencies All dependencies will be compiled to a directory in the user's HOME directory: <pre> export MY_VIDEO_LIBS=$HOME/work/ag-projects/video/local </pre> h3. libx264 <pre> ./configure --enable-shared --disable-avs --disable-swscale --disable-lavf --disable-ffms --disable-gpac --prefix=$MY_VIDEO_LIBS make make install # If a 32bit build is wanted, then run this configure instead: ./configure --host=i386-apple-darwin --enable-shared --disable-avs --disable-swscale --disable-lavf --disable-ffms --disable-gpac --prefix=$MY_VIDEO_LIBS </pre> h3. ffmpeg <pre> # Some exports export PKG_CONFIG_PATH=$MY_VIDEO_LIBS/lib/pkgconfig ./configure --enable-shared --disable-static --enable-memalign-hack --enable-gpl --enable-libx264 --prefix=$MY_VIDEO_LIBS --extra-cflags="`pkg-config --cflags x264`" --extra-ldflags="`pkg-config --libs x264`" make make install # If a 32bit build is wanted do: ./configure --enable-shared --disable-static --enable-memalign-hack --enable-gpl --enable-libx264 --prefix=$MY_VIDEO_LIBS --extra-cflags="`pkg-config --cflags x264`" --extra-ldflags="`pkg-config --libs x264`" --cc="gcc -m32" --disable-asm # TODO: I WANT MY ASM </pre> h3. SDL <pre> ./configure --disable-audio --prefix=$MY_VIDEO_LIBS make make install # If a 32bit build is wanted: CFLAGS="-arch i386" CXXFLAGS="-arch i386" LDFLAGS="-arch i386" ./configure --disable-audio --prefix=$MY_VIDEO_LIBS </pre> h2. Compiling PJSIP (pjsua, for testing) <pre> svn co http://svn.pjsip.org/repos/pjproject/trunk pjsip cd pjsip echo "#define PJMEDIA_HAS_VIDEO 1" > pjlib/include/pj/config_site.h ./configure --with-sdl=$MY_VIDEO_LIBS --with-ffmpeg=$MY_VIDEO_LIBS make dep make # pjsua will be located in pjsip-apps/bin/ </pre> h2. Proposed API API for video components is based on 2 different types of video capable entities: * VideoProducer: a source for video data, for example a video camera or a remote video stream * VideoConsumer: a sink or destination for video data, for example a video rendering window h3. Data flow Data flow works in _pull_ fashion, that is, a producer doesn't start to produce data until there is a consumer which will consume it. h3. VideoProducer Produces video data. Internal API: * _add_consumer: attach a consumer, called by the consumer * _remove_consumer: detach a consumer from a producer, called by the consumer * _start: start producing video data * _stop: stop producing video data Public API: * close: remove all consumers and stop producing video data * producer_port: pointer to the pjmedia_port object h3. VideoConsumer Consumes video data. Internal API: * _start: start consuming video data * _stop: stop consuming video data Public API: * attach: tie this consumer to a producer, in order to render the video data generated by the producer * detach: untie this consumer from a producer * consumer_port: pointer to the pjmedia_port object h3. Producer and consumer objects * VideoDevice: Producer, acquires video from a user camera. * VideoWindow: Consumer, renders video in an SDL window. Extra methods: show/hide. Properties: native_handle, size. * LocalVideoStream: Consumer, takes video from a VideoDevice and sends it to the remote party. * RemoteVideoStream: Producer, produces video sent by the remote party. These are just theoretical objects, won't be implemented in the first go. * VideoFile: Consumer, saves incoming video data to a video file. * VideoFilePlayer: Producer, produces video data out of a video file. * VideoMixer: Producer/Consumer, consumes video from multiple sources and produces aggregated video data.