Hi. We're trying to build an application on a Fedora 7 Linux platform that takes a webcam feed and streams it to mobile devices. Our first attempt was a custom application using the ffmpeg libraries, but the ffmpeg codecs couldn't handle the ASF stream. We then tried mplayer, and it played the audio/video flawlessly. But we've had trouble hooking mplayer into our streaming app. Our first thought was to use mplayer's codecs, but mplayer doesn't install its libraries separately, so there's no way to link to them. We then tried using FIFOs to capture the decoded audio and video, using mplayer -ao pcm:file=audio-fifo -vo yuv4mpeg:file=video-fifo The behaviour we're seeing is that it connects and buffers correctly, but that it passes through the audio and video in bursts. It does nothing for about four seconds, then writes all the accumulated audio and video in one hit, waits another four seconds, and so on. That's no good for us. If we use -nosound the video streams smoothly, but we need audio for this application. The pcm:fast and -autosync options make no difference. We even read from the audio FIFO read at the correct rate so mplayer's audio write process should block periodically. Is there any way to fix this problem? As a last resort we could re-write ao_pcm.c to check if writing would block and delay accordingly, but that's not desirable. Our server runs off RPMs, and compiling and maintaining a custom version of mplayer adds a lot of support overheads. Is there a way to make audio and video stream smoothly to an external application using the existing executable? Below are the mplayer diagnostics from the stream we're using. Regards, mkwan MPlayer 1.0rc1-4.1.2 (C) 2000-2006 MPlayer Team CPU: Intel Celeron 2/Pentium III Coppermine,Geyserville (Family: 6, Model: 8, Stepping: 6) CPUflags: MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 0 Can't open joystick device /dev/input/js0: No such file or directory Can't init input joystick mplayer: could not connect to socket mplayer: No such file or directory Failed to open LIRC support. You will not be able to use your remote control. Playing http://XXX.XX.192.14/img/video.asf. Resolving XXX.XX.192.14 for AF_INET6... Couldn't resolve name for AF_INET6: XXX.XX.192.14 Connecting to server XXX.XX.192.14[XXX.XX.192.14]: 80... Cache size set to 320 KBytes Cache fill: 15.00% (49152 bytes) ASF file format detected. VIDEO: [M4S2] 320x240 24bpp 1000.000 fps 0.0 kbps ( 0.0 kbyte/s) Using (default) progressive frame mode.========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4) ========================================================================== ========================================================================== Opening audio decoder: [acm] Win32/ACM decoders Loading codec DLL: 'scg726.acm' Win32 LoadLibrary failed to load: scg726.acm, /usr/lib/codecs/scg726.acm, /usr/lib/win32/scg726.acm, /usr/local/lib/win32/scg726.acm Can't open library scg726.acm ACM_Decoder: Unappropriate audio format Could not load/initialize Win32/ACM audio codec (missing DLL file?). ADecoder preinit failed :( ADecoder init failed :( Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders AUDIO: 8000 Hz, 1 ch, s16le, 16.0 kbit/12.50% (ratio: 2000->16000) Selected audio codec: [ffg726] afm: ffmpeg (Sharp G.726 Audio) ========================================================================== [AO PCM] File: foo.wav (WAVE) PCM: Samplerate: 8000Hz Channels: Mono Format s16le [AO PCM] Info: Faster dumping is achieved with -vc null -vo null -ao pcm:fast [AO PCM] Info: To write WAVE files use -ao pcm:waveheader (default). AO: [pcm] 8000Hz 1ch s16le (2 bytes per sample) Starting playback... VDec: vo config request - 320 x 240 (preferred colorspace: Planar YV12) VDec: using Planar YV12 as output csp (no 0) Movie-Aspect is 1.33:1 - prescaling to correct movie aspect. VO: [yuv4mpeg] 320x240 => 320x240 Planar YV12 A: 12.3 V: 7.5 A-V: 4.780 ct: -0.625 51/ 51 1% 1% 152.8% 50 0 1% ************************************************ **** Your system is too SLOW to play this! **** ************************************************ Possible reasons, problems, workarounds: - Most common: broken/buggy _audio_ driver - Try -ao sdl or use the OSS emulation of ALSA. - Experiment with different values for -autosync, 30 is a good start. - Slow video output - Try a different -vo driver (-vo help for a list) or try -framedrop! - Slow CPU - Don't try to play a big DVD/DivX on a slow CPU! Try some of the lavdopts, e.g. -vfm ffmpeg -lavdopts lowres=1:fast:skiploopfilter=all. - Broken file - Try various combinations of -nobps -ni -forceidx -mc 0. - Slow media (NFS/SMB mounts, DVD, VCD etc) - Try -cache 8192. - Are you using -cache to play a non-interleaved AVI file? - Try -nocache. Read DOCS/HTML/en/video.html for tuning/speedup tips. If none of this helps you, read DOCS/HTML/en/bugreports.html. A: 20.5 V: 16.9 A-V: 3.552 ct: -1.253 109/109 1% 1% 104.1% 97 0 1% Exiting... (Quit) _______________________________________________ MPlayer-users mailing list MPlayer-users@xxxxxxxxxxxx https://lists.mplayerhq.hu/mailman/listinfo/mplayer-users
