使用python-gstreamer播放RTSP [英] Playing RTSP with python-gstreamer

问题描述

我使用gstreamer播放来自IP摄像机(如Axis)的RTSP流. 我使用这样的命令行:

I use gstreamer for playing RTSP stream from IP cameras (like Axis.) I use a command line like this:

gst-launch-0.10 rtspsrc location=rtsp://192.168.0.127/axis-media/media.amp latency=0 ! decodebin ! autovideosink

它工作正常.

我想用pygtk中的gui控制它，所以我使用了gstreamer python绑定. 我已经编写了这段代码:

I want to control it with a gui in pygtk so I use the gstreamer python bindings. I've wrote this piece of code:

[...]
self.player = gst.Pipeline("player")
source = gst.element_factory_make("rtspsrc", "source")
source.set_property("location", "rtsp://192.168.0.127/axis-media/media.amp")
decoder = gst.element_factory_make("decodebin", "decoder")
sink = gst.element_factory_make("autovideosink", "sink")

self.player.add(source, decoder, sink)
gst.element_link_many(source, decoder, sink)

bus = self.player.get_bus()
bus.add_signal_watch()
bus.enable_sync_message_emission()
bus.connect("message", self.on_message)
bus.connect("sync-message::element", self.on_sync_message)
[...]

但是它不起作用，并退出并显示以下消息:

But it doesn't work and quit with this message:

gst.element_link_many(source, decoder,sink)
gst.LinkError: failed to link source with decoder

由于我只使用h264，因此我也尝试通过此方法改进CLI:

I've also try to improve my CLI with this as I only use h264:

gst-launch-0.10 -v rtspsrc location=rtsp://192.168.0.127/axis-media/media.amp ! rtph264depay !  ffdec_h264 ! xvimagesink

并在我的python代码中实现该代码:

And implement it in my python code like that:

[...]
self.player = gst.Pipeline("player")
source = gst.element_factory_make("rtspsrc", "source")
depay = gst.element_factory_make("rtph264depay", "depay")
decoder = gst.element_factory_make("ffdec_h264", "decoder")
sink = gst.element_factory_make("xvimagesink", "output")

self.player.add(source, depay, decoder, sink)
gst.element_link_many(source, depay, decoder, sink)
[...]

但是我遇到了同样的错误:(

But I got the same error :(

gst.LinkError: failed to link source with depay

我的源(rtspsrc)之间出了点问题，因为它与带filesrc的decodebin一起工作(当然，与rtph264depay一起工作)

There is something wrong between my source (rtspsrc), as it work with decodebin with a filesrc (don't work of course with rtph264depay)

我不明白为什么它不起作用，因为它在cli中起作用. gstreamer的任何专家可以帮助我吗?

I don't understand why it doesn't work because it work in cli. Any experts of gstreamer who can help me ?

谢谢.

此致

推荐答案

我对要查找的代码具有"C"实现.我认为转换为"Python"应该相当简单

I have a "C" implementation of the code you are looking for. I think it should be fairly simple to convert to "Python"

 //Display RTSP streaming of video
 //(c) 2011 enthusiasticgeek
 // This code is distributed in the hope that it will be useful,
 // but WITHOUT ANY WARRANTY; without even the implied warranty of
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

#include <string.h>
#include <math.h>
#include <gst/gst.h>
#include <glib.h>

static gboolean bus_call (GstBus *bus,GstMessage *msg, gpointer data){
  GMainLoop *loop = (GMainLoop *) data;

  switch (GST_MESSAGE_TYPE (msg)) {

    case GST_MESSAGE_EOS:
      g_print ("Stream Ends\n");
      g_main_loop_quit (loop);
      break;

    case GST_MESSAGE_ERROR: {
      gchar  *debug;
      GError *error;

      gst_message_parse_error (msg, &error, &debug);
      g_free (debug);

      g_printerr ("Error: %s\n", error->message);
      g_error_free (error);

      g_main_loop_quit (loop);
      break;
    }
    default:
      break;
  }

  return TRUE;
}

static void on_pad_added (GstElement *element, GstPad *pad, gpointer data){

  GstPad *sinkpad;
  GstElement *decoder = (GstElement *) data;

  /* We can now link this pad with the rtsp-decoder sink pad */
  g_print ("Dynamic pad created, linking source/demuxer\n");

  sinkpad = gst_element_get_static_pad (decoder, "sink");

  gst_pad_link (pad, sinkpad);

  gst_object_unref (sinkpad);
}

int main (int argc, char *argv[])
{
  GMainLoop *loop;
  GstBus *bus;
  GstElement *source;
  GstElement *decoder;
  GstElement *sink;
  GstElement *pipeline;
  GstElement *demux;
  GstElement *colorspace;

  /* Initializing GStreamer */
  gst_init (&argc, &argv);
  loop = g_main_loop_new (NULL, FALSE);

 //gst-launch-0.10 rtspsrc location=rtsp://<ip> ! decodebin ! ffmpegcolorspace ! autovideosink
 //gst-launch -v rtspsrc location="rtsp://<ip> ! rtpmp4vdepay ! mpeg4videoparse ! ffdec_mpeg4 ! ffmpegcolorspace! autovideosink
 //gst-launch -v rtspsrc location="rtsp://<ip> ! rtpmp4vdepay ! ffdec_mpeg4 ! ffmpegcolorspace! autovideosink
  /* Create Pipe's Elements */
  pipeline = gst_pipeline_new ("video player");
  g_assert (pipeline);
  source   = gst_element_factory_make ("rtspsrc", "Source");
  g_assert (source);
  demux = gst_element_factory_make ("rtpmp4vdepay", "Depay");
  g_assert (demux);
  decoder = gst_element_factory_make ("ffdec_mpeg4", "Decoder");
  g_assert (decoder);
  colorspace     = gst_element_factory_make ("ffmpegcolorspace",  "Colorspace");
  g_assert(colorspace);
  sink     = gst_element_factory_make ("autovideosink", "Output");
  g_assert (sink);

  /*Make sure: Every elements was created ok*/
  if (!pipeline || !source || !demux || !decoder || !colorspace || !sink) {
    g_printerr ("One of the elements wasn't create... Exiting\n");
    return -1;
  }

  g_printf(" \nPipeline is Part(A) ->(dynamic/runtime link)  Part(B)[ Part(B-1) -> Part(B-2) -> Part(B-3) ]\n\n");
  g_printf(" [source](dynamic)->(dynamic)[demux]->[decoder]->[colorspace]->[videosink] \n\n");

  /* Set video Source */
  g_object_set (G_OBJECT (source), "location", argv[1], NULL);
  //g_object_set (G_OBJECT (source), "do-rtcp", TRUE, NULL);
  g_object_set (G_OBJECT (source), "latency", 0, NULL);

  /* Putting a Message handler */
  bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
  gst_bus_add_watch (bus, bus_call, loop);
  gst_object_unref (bus);

  /* Add Elements to the Bin */
  gst_bin_add_many (GST_BIN (pipeline), source, demux, decoder, colorspace, sink, NULL);

  /* Link confirmation */
  if (!gst_element_link_many (demux, decoder, colorspace, sink, NULL)){
     g_warning ("Linking part (B) Fail...");
  }

  g_printf("\nNote that the source will be linked to the demuxer(depayload) dynamically.\n\
     The reason is that rtspsrc may contain various elements (for example\n\
     audio and video). The source pad(s) will be created at run time,\n\
     by the rtspsrc when it detects the amount and nature of elements.\n\
     Therefore we connect a callback function which will be executed\n\
     when the \"pad-added\" is emitted.\n");

  /* Dynamic Pad Creation */
  if(! g_signal_connect (source, "pad-added", G_CALLBACK (on_pad_added),demux))
  {
    g_warning ("Linking part (A) with part (B) Fail...");
  }
  /* Run the pipeline */
  g_print ("Playing: %s\n", argv[1]);
  gst_element_set_state (pipeline, GST_STATE_PLAYING);
  g_main_loop_run (loop);

  /* Ending Playback */
  g_print ("End of the Streaming... ending the playback\n");
  gst_element_set_state (pipeline, GST_STATE_NULL);

  /* Eliminating Pipeline */
  g_print ("Eliminating Pipeline\n");
  gst_object_unref (GST_OBJECT (pipeline));

  return 0;
}

Makefile

test = test12
ext = c
CC = gcc
CPP = g++
gstreamer:
    $(CC) -g $(test).$(ext) -o $(test) `pkg-config gstreamer-0.10 --libs --cflags` `pkg-config gtk+-2.0 --libs --cflags`
clean:
    rm -rf $(test)

更新

等效的Java代码

 // Display RTSP streaming of video
 // (c) 2011 enthusiasticgeek
 // This code is distributed in the hope that it will be useful,
 // but WITHOUT ANY WARRANTY; without even the implied warranty of
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
 // Leave Credits intact

package video2; //replace this with your package
import java.awt.BorderLayout;
import java.awt.Dimension;

import javax.swing.JFrame;
import javax.swing.SwingUtilities;

//import org.gstreamer.Caps;
import org.gstreamer.Element;
import org.gstreamer.ElementFactory;
import org.gstreamer.Gst;
import org.gstreamer.Pad;
import org.gstreamer.PadDirection;
import org.gstreamer.Pipeline;
import org.gstreamer.swing.VideoComponent;

/**
 * A Simple videotest example.
 */
public class Main {
    public Main() {
    }
    private static Pipeline pipe;
    public static void main(String[] args) {
    // Quartz is abysmally slow at scaling video for some reason, so turn it off.
    System.setProperty("apple.awt.graphics.UseQuartz", "false");

    args = Gst.init("SwingVideoTest", args);

    pipe = new Pipeline("pipeline");
    /*
    final Element videosrc = ElementFactory.make("videotestsrc", "source");
    final Element videofilter = ElementFactory.make("capsfilter", "flt");
    videofilter.setCaps(Caps.fromString("video/x-raw-yuv, width=720, height=576"
            + ", bpp=32, depth=32, framerate=25/1"));
    */

     pipe.getBus().connect(new Bus.ERROR() {
        public void errorMessage(GstObject source, int code, String message) {
            System.out.println("Error occurred: " + message);
            Gst.quit();
        }
    });
    pipe.getBus().connect(new Bus.STATE_CHANGED() {
        public void stateChanged(GstObject source, State old, State current, State pending) {
            if (source == pipe) {
                System.out.println("Pipeline state changed from " + old + " to " + current);
            }
        }
    });
    pipe.getBus().connect(new Bus.EOS() {
        public void endOfStream(GstObject source) {
            System.out.println("Finished playing file");
            Gst.quit();
        }
    });        

     pipe.getBus().connect(new Bus.TAG() {
        public void tagsFound(GstObject source, TagList tagList) {
            for (String tag : tagList.getTagNames()) {
                System.out.println("Found tag " + tag + " = "
                        + tagList.getValue(tag, 0));
            }
        }
    });

    final Element source = ElementFactory.make("rtspsrc", "Source");
    final Element demux = ElementFactory.make("rtpmp4vdepay", "Depay");
    final Element decoder=ElementFactory.make("ffdec_mpeg4", "Decoder");
    final Element colorspace = ElementFactory.make("ffmpegcolorspace",  "Colorspace");
    //final Element sink = ElementFactory.make ("autovideosink", "Output");

    SwingUtilities.invokeLater(new Runnable() {

        public void run() {
            // Create the video component and link it in
            VideoComponent videoComponent = new VideoComponent();
            Element videosink = videoComponent.getElement();

           source.connect(new Element.PAD_ADDED() {
           public void padAdded(Element element, Pad pad) {
            pad.link(demux.getStaticPad("sink"));
           }
            });

           Pad p = new Pad(null, PadDirection.SRC);
           source.addPad(p);

            source.set("location","rtsp://<user>:<pass>@<ip>/mpeg4/1/media.amp");  //replace this with your source

            pipe.addMany(source, demux, decoder, colorspace, videosink);
            Element.linkMany(demux, decoder, colorspace, videosink);

            // Now create a JFrame to display the video output
            JFrame frame = new JFrame("Swing Video Test");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.add(videoComponent, BorderLayout.CENTER);
            videoComponent.setPreferredSize(new Dimension(720, 576));
            frame.pack();
            frame.setVisible(true);

            // Start the pipeline processing
            pipe.play();
        }
    });
    }
}

这篇关于使用python-gstreamer播放RTSP的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！