Hi,  I tried the command and got the response below:       Joyious He schrieb:     >  Hi all,     >     > Now I'm going to test the video display on my target arm borad.it use     > the directfb as the display layer.and I got problems below:     >     >     > 1:The videotestsrc work well for that dfb-example,but when i just get     > the command line "gst-launch -v videotestsrc ! dfbvideosink", it threw     > out some err msg: "format can not negotiate".     gst-launch -v videotestsrc ! ffmpegcolorspace ! dfbvideosink  ************************************************************************************************* gst-launch -v videotestsrc ! ffmpegcolorspace ! dfbvideosink ERROR: from element /pipeline0/videotestsrc0: Could not negotiate format Additional debug info: gstbasesrc.c(1865): gst_base_src_start (): /pipeline0/videotestsrc0: Check your filtered caps, if any this work well on my PC, but not on the board, I tried to use GST_DEBUG to get more msg, but at most condition it will got err: Caught SIGSEGV accessing address (nil) Spinning.  Please run 'gdb gst-launch 1532' to continue debugging, Ctrl-C to quit, or Ctrl-\ to dump core. *************************************************************************************************     >     > 2:Then I put the videotestsrc away, try to play some AVI files.but when     > I try the application or the command line like : " gst-launch -v filesrc     > location=/convertavi ! avidemux name=demux demux.video_00 ! queue !     > decodebin ! ffmpegcolorspace ! videoscale ! dfbvideosink". Iwas told the     > pipeline was pause. I check the debug message.I got the reason:     filesrc location=/convertavi ! decodebin name=demux demux.video_00 ! queue !     decodebin ! ffmpegcolorspace ! videoscale ! dfbvideosink *************************************************************************************************** gst-launch -v filesrc location=/convert.avi ! decodebin name=demux demux.video_00 ! queue ! decodebin ! ffmpegcolorspace ! videoscale ! dfbvideosink ERROR: from element /pipeline0/demux/avidemux0: Internal data stream error. Additional debug info: gstavidemux.c(3577): gst_avi_demux_loop (): /pipeline0/demux/avidemux0: streaming stopped, reason not-linked I got the debug message and the reason for this not-linked is when using decodebin, it will try to get link to the demux.audio_00, I did not get audio sink this pipeline, so it gave the not-link err. ************************************************************************************************************ then i replace this decodebin with mpeg2dec,thus : gst-launch -v filesrc location=/convert.avi ! avidemux name=demux demux.video_00 ! mpeg2dec ! ffmpegcolorspace ! videoscale ! dfbvideosink ERROR: from element /pipeline0/demux: Internal data stream error. Additional debug info: gstavidemux.c(3577): gst_avi_demux_loop (): /pipeline0/demux: streaming stopped, reason not-negotiated 0:00:12.098377000   968 0xa3920 WARN              avidemux gstavidemux.c:1616:gst_avi_demux_stream_index:<demux> skip LIST chunk /pipeline0/mpeg2dec0.sink: caps = video/mpeg, systemstream=(boolean)false, mpegversion=(int)2, framerate=(fraction)25/1, width=(int)128, height=(int)112 /pipeline0/mpeg2dec0.src: caps = video/x-raw-yuv, format=(fourcc)I420, width=(int)128, height=(int)112, pixel-aspect-ratio=(fraction)1/1, framerate=(fraction)25/1 0:00:13.109244000   968 0xa3920 WARN              avidemux gstavidemux.c:3548:gst_avi_demux_loop: stream_movi flow: not-negotiated / not-negotiated 0:00:13.110534000   968 0xa3920 WARN              avidemux gstavidemux.c:3577:gst_avi_demux_loop:<demux> error: Internal data stream error. 0:00:13.111456000   968 0xa3920 WARN              avidemux gstavidemux.c:3577:gst_avi_demux_loop:<demux> error: streaming stopped, reason not-negotiated ERROR: from element /pipeline0/demux: Internal data stream error. Additional debug info: gstavidemux.c(3577): gst_avi_demux_loop (): /pipeline0/demux: streaming stopped, reason not-negotiated **********************************************************************************************************************     >     > "0:00:01.613967000 [332m 1633[00m 0x1af80 [32;01mINFO [00m [00;01;34m     > GST_EVENT gstpad.c:4242:gst_pad_send_event:<mpeg2dec0:sink>[00m Received     > event on flushing pad. Discarding     > 0:00:01.614717000 [332m 1633[00m 0x1af80 [32;01mINFO [00m [00;01;34m     > GST_EVENT gstpad.c:4242:gst_pad_send_event:<mpeg2dec0:sink>[00m Received     > event on flushing pad. Discarding     > 0:00:01.616135000 [332m 1633[00m 0x1af80 [32;01mINFO [00m [00;01;34m     > GST_EVENT gstpad.c:4242:gst_pad_send_event:<mpeg2dec0:sink>[00m Received     > event on flushing pad. Discarding     > 0:00:01.617260000 [332m 1633[00m 0x1af80 [33;01mWARN [00m [00m avidemux     > gstavidemux.c:3548:gst_avi_demux_loop:[00m stream_movi flow: wrong-state     > / ok"     >     > 3:I also tried another way. I convert a AVI file into a raw data as a     > temp file, and use filesrc and dfbvideo sink to play :"gst-launch -v     > filesrc location=/convert2 blocksize=65536 ! dfbvideosink". Some thing     > is coming out, but its not the correct video.I think it's probably the     > frame format mismatching. the temp file is using YV12(I convert it using     > mplayer and its default value is YUV YV12) and my directfb is using     > RGB32. So how can i specify the caps convert, changing the format of     > mplayer default or specify it in the gstreamer commad line? I tried the     > ffmpegcolorspace like "gst-launch -v filesrc location=/convert2     > blocksize=65536 ! ffmpegcolorspace ! dfbvideosink" and I was told the     > format can not negotiated. *********************************************************************************************************************** Here i got the frame displayed on the board,just using the capsfilter to specify the caps format: GST_DEBUG="dfbvideosink:3" gst-launch -v filesrc location="/t3" blocksize=57344 ! video/x-raw-rgb,bpp=32,depth=32,width=128,height=112,framerate=25/1,endianness=4321,pixel-aspect-ratio=1/1,red_mask=65280, green_mask=16711680, blue_mask=-16777216, alpha_mask=255 ! dfbvideosink **********************************************************************************************************************     >     > Could you all give me any ideas about all the problems above ?     >     Do I get a free device when it gets released :) If i can get some in hand, of cause I'll get one diliver to you. But it seems not possible for me to get any then :(     Stefan     >     > Thanks very much.     >     > Best Regard     > Joyious     >       >       >       >     >     > ------------------------------------------------------------------------     > LOGO     把爱心注入牛奶，共同凝聚这份力量     > <http://popme.163.com/link/003515_0929_938.html>     > 快来参加蒙牛免费赠奶爱心行动     > <http://popme163.com/link/003515_0929_938.html>     >     >     > ------------------------------------------------------------------------     >     > -------------------------------------------------------------------------     > This SF.net email is sponsored by: Splunk Inc.     > Still grepping through log files to find problems?  Stop.     > Now Search log events and configuration files using AJAX and a browser.     > Download your FREE copy of Splunk now >> http://get.splunk.com/     >     >     > ------------------------------------------------------------------------     >     > _______________________________________________     > gstreamer-devel mailing list     > gstreamer-devel@lists.sourceforge.net     > https://lists.sourceforge.net/lists/listinfo/gstreamer-devel  <hr> <table width="100%%" border="0" cellspacing="0" cellpadding="0"> <tr> <td width="50" height="50"><img src="http://mimg.163.com/hd/163/163footer/163footer_50.jpg" alt="LOGO" width="50" height="50"></td> <td style="padding:5px;"><a style="font-size:12px;color:black; line-height:20px;text-decoration:none;" href="http://popme.163.com/link/003515_0929_938.html">把爱心注入牛奶，共同凝聚这份力量</a> <a style="font-size:12px;line-height:20px; color:black; text-decoration:none;" href="http://popme.163.com/link/003515_0929_938.html">快来参加蒙牛免费赠奶爱心行动 </a></td> </tr> </table>