<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=gb2312"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style></style></head><body lang=ZH-CN link=blue vlink=purple><div class=WordSection1>Dear Peter,<o:p></o:p><o:p> </o:p>Thanks so much for your notes, they are very helpful.<o:p></o:p><o:p> </o:p>About the ff-mpeg pakage, I had googled it before installing the gst-libav-1.0.5. I found that, the version of gst-ffmpeg has been updated to gst-libav since gst-ffmpeg-0.11.2. So I installed the latest version of gst-libav and it came out that vdpauh264dec was installed.<o:p></o:p><o:p> </o:p>By the way, I am using opensuse-12.3 OS, the version of gstreamer installed is 1.0.5. Now, I can get the following stuff after typing “gst-inspect-1.0 | grep 264” :<o:p></o:p> Libav: avdec_h264: libav H.264/AVC/MPEG-4 AVC/MPEG-4 part 10 decoder<o:p></o:p> Libav: avmux_ipod : libav iPod H.264 MP4 format muxer.<o:p></o:p>And the h264_parser and rtp264pay, rtp264depay are all gone. I don’t know why.<o:p></o:p>Anyway, I have one of my pc installed Ubuntu-12.4. I will try it later on.<o:p></o:p><o:p> </o:p>All BEST!<o:p></o:p><o:p> </o:p>Gavin<o:p></o:p><o:p> </o:p>发件人: gstreamer-devel-bounces+gavinsperation=hotmail.com@lists.freedesktop.org [mailto:gstreamer-devel-bounces+gavinsperation=hotmail.com@lists.freedesktop.org] 代表 Peter Maersk-Moller 发送时间: 2013年7月18日 19:27 收件人: Discussion of the development of and with GStreamer 主题: Re: how to choose a h264 decoder in gstreamer plugins<o:p></o:p><o:p> </o:p><div><div><div><div><div><div><div><div><div><div><div><div>Hi Gavin.det<o:p></o:p></div>You asked for a h264 decoder and mention a few modules. Here are som comments.<o:p></o:p></div>1) h264_parse is not a decoder, but rather a module to parse a h264 stream. It may be able to convert a h264 stream from NAL units to AU units and perhaps vice versa, but that's it. You use it in a stream to ensure that the following modules will receive the right caps information and perhaps for the unit conversion.<o:p></o:p></div>2) rtpXXXpay and rtpXXXdepay are modules used to encapsulate and decapsulate a stream for RTP streaming. In your case you may only need the modules, if you need to decapsulate an RTP stream.<o:p></o:p></div>3) Never used vdpauh264dec, so search Google for examples.<o:p></o:p></div>Now for decoding h264, you can among other things also do<o:p></o:p></div> a) use ffdec_h264<o:p></o:p></div> b) use decodebin and decodebin2<o:p></o:p></div> c) use playbin and playbin2<o:p></o:p></div>Note that solution a) requires you to do proper decapsulating and/or proper demuxing before you can decode.<o:p></o:p></div>Now for why you are missing the h264 decoder, it depends on you OS, your installed packages, your version of GStreamer etc. On one of my systems I'm using Ubuntu 12.04 LTS and GStreamer-0.10. To get h264 decoder support I need to install gstreamer0.10-ffmpeg package. You can try the following $ gst-inspect |grep 264 When I do, I see this: ffmpeg: ffdec_h264: FFmpeg H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 decoder ffmpeg: ffmux_ipod: FFmpeg iPod H.264 MP4 format muxer rtp: rtph264depay: RTP H264 depayloader rtp: rtph264pay: RTP H264 payloader x264: x264enc: x264enc videoparsersbad: h264parse: H.264 parser h264parse: legacyh264parse: H264Parse typefindfunctions: video/x-h264: h264, x264, 264<o:p></o:p></div><div>What you see should give you a clue.<o:p></o:p></div><div>Best regards<o:p></o:p></div><div>Peter Maersk-Moller<o:p></o:p></div></div><div><o:p> </o:p><div>On Thu, Jul 18, 2013 at 8:56 AM, liuxing <<a href="mailto:gavinsperation@hotmail.com" target="_blank">gavinsperation@hotmail.com</a>> wrote:<o:p></o:p><div><div>Hello, there<o:p></o:p> <o:p></o:p>I am now working a real-time h264 video stream player. I checked the plugins related to h264 installed on my computer, they are h264 parser and rtph264pay and rtph264depay. There is no h264 decoder that I can use directly. Then, I googled “gst-libav” and got it installed on my computer. Now I have vdpauh264dec, but I still have no clue to get it work with h264 files. And when I try to play “mov” or “mp4” file with gst-launch playbin, the fault “h264 decoder missing” came up. Why is it????<o:p></o:p> <o:p></o:p>Can anyone help me with this please? <o:p></o:p> <o:p></o:p>With Regards<o:p></o:p> <o:p></o:p>Gavin <o:p></o:p></div></div> _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><o:p></o:p></div><o:p> </o:p></div></div></body></html>