000000 fps, w x h = 3840 x 2160…. mkv) : gst-launch-1. ‘rate’ defines the desired playback rate: 0 == Stop playback, 1 == Normal speed forward, -1 == Normal speed backward, … . this is my sender: Sender. 17_1. The "new" va series gstreamer plugins work much better than the older plugins, but due to current GTK limitation they are working on Wayland only. , with easy ways of adjusting playback speed, length of breaks, the number of repeats and Feb 12, 2019 · Hello everyone, I am currently building a project where we aim to: “Live stream a drone video over 4G network in real time (~500 ms Latency) and broadcast to a website”. That will lead to a distorted image on Feb 21, 2024 · I see a duration of 10. Aug 5, 2020 · change playback rate; EXPECTED RESULT: pitch stays the same and audio is faster/slower. g. . x API and can be found here: The step event can skip a specified interval (which can only be played forward) with the subsequent playback speed changed. videorate. on android (at least), seeking is impossible with opus files almost always (have experimented a very few times that it does work), whereas it works just fine with Package – GStreamer Bad Plug-ins. I am using the following command for a gstreamer pipeline for a videostream from a webcam: gst-launch-1. GStreamer provides support for the following use cases: Non-live sources with access faster than playback rate. 0 for normal playback, greater than 1. The application consists of a Simple Video Player with several capabilities: Regular video playback. Playback tutorial 5: Color Balance. 0 filesrc location=bar. 0 results in slower playback. streamsynchronizer. fps = 52. The correction is performed by dropping and duplicating frames, no fancy algorithm is used to interpolate frames (yet). 83 seconds: gst-launch-1. Gstreamer pipeline to play mpegts file works in version 0. Nov 1, 2017 · Your protocols chosen basically ensure that no data is lost. Whilst the command line is great, programmatic usage (in Python or another language) allows you to dynamically manipulate the A/V streams. Generic. But obviously this results in your described behavior. Trick modes (fast-forward, speed change, seek to position). {mex*} subfunction. I'm not sure how gstreamer compares. nveglglessink (windowed video playback, NVIDIA EGL/GLES videosink using default X11 backend): Enter this command to start the GStreamer pipeline using nveglglesink with the default X11 backend: Feb 10, 2015 · 5. Jun 11, 2024 · The following examples show how you can perform video playback using GStreamer-1. The playback speed is slower. As you can see, processing each individual frame of the 31 second video clip takes approximately 47 seconds with a FPS processing rate of 20. I have achieved this by using ‘videorate rate’ element. mov, afterwards the video playback stops. c -o playback-tutorial-3 `pkg-config --cflags --libs gstreamer-1. This flow seems to be causing some failure on Nov 24, 2015 · When implementing a GStreamer 1. The process is as follow: Gstreamer[HDMI video feed → H264 encode → RTP → UDP sink] —> Kurento[rtp → webRTC] → [b]browser [/b]We successfully live streamed over WAN via ethernet and achieved required latency Jan 13, 2020 · The modofications solve two problems regarding issues hzeller#198 and hzeller#202: hzeller#198: modifications in my_bus_callback ensure that after the last URI is played gstreamer is REALLY stopped and that the URI is cleared. This tutorial opens a window and displays a movie, with accompanying audio. Contributor III Mark as New; Bookmark; Subscribe; Mute; Jul 23, 2014 · I have a question about i. h so all function names and objects are properly defined. Ask Question Asked 7 years ago. The way it is set up right now, the speed should be doubled when a '. This is the output of the code: ITER=1::Movie: path\DevilMayCry5. By default, the resampler uses a reduced sinc table, with cubic interpolation filling in the gaps. 20. Synchronizes a group of streams to have equal durations and starting points. mp4" ! qtdemux ! h264parse ! avdec_h264 ! videoconvert ! autovideosink We've learned, in Initializing GStreamer, that the first thing to do in your application is to initialize GStreamer by calling gst_init (). This GStreamer Daemon version is deprecated. Sep 27, 2023 · Hi all, This was the talk I gave at GStreamer Conference 2023 Over the past 2 years, a new set of “Adaptive demuxers” (to support HLS, DASH, MSS) has appeared, along with a in-depth refactoring of the new playback elements (playbin3, decodebin3, …). Restart VLC for this change to take effect. It is powered by GStreamer so it can decode everything that GStreamer can (and it is a lot). 0 gstreamer-audio-1. Is there anyway to get this to loop repeatidly? i. This value is a multiplier applied to the media's standard playback rate. frame_width = 640. gcc playback-tutorial-1. gcc playback-tutorial-4. Lets try a seek: / # gst-client -p 1 seek 20 Parse single command interactive: Ok. Not all movie files Feb 19, 2021 · This is one concrete usage example of the GStreamer Daemon along with a Python Application. May 5, 2006 · I can see GStreamer trick modes being useful for playing back language audio, for instance, when slowing down “tape speech” is desired. By default this value is 1. visualisations for audio files. I have no experience and technical background about this topic so I am just wondering If I can decode 50 fps - decoding original frames not duplicating or Jun 7, 2024 · Psychtoolbox > Screen . For this purpose, GStreamer provides a synchronization mechanism. A new version was written from scratch on C in 2017 to take advantage of the GStreamer 1. You can try experimenting with ~100ms and then adjust according to how it performs. I get extremely high CPU consumption. rtspsrc strictly follows RFC 2326 and therefore does not (yet) support RealMedia/Quicktime/Microsoft extensions. May 24, 2017 · I am pretty new to Gstreamer. Hi all, I am having an issue with the speed of playback of an MPEG transport stream. However the fast forward for the same video file works fine. Our partner want to know how to adjust a video playback speed of gstreamer. ! video/x-raw,format=YUY2,width=320,height=320. mp4 : 10. uridecodebin Obtains the playback rate, or speed of the media. As for hwaccel, the older gstreamer-vaapi plugins support: h264, h265, mjpeg, mpeg2 and vc1. 0 ? I mean I want to be able to playback some media at 1. For instance, it happens when I execute the following command: ! videoscale. It manages all aspects of media playback, from source to display, passing through demuxing and decoding. 22 API. ADDITIONAL INFORMATION: This issue might have been introduced with SFOS 3. 1:8888 (localhost) or a remote server is set up. If you need help to run this code, refer to the Running the tutorials section for your platform: Linux, Mac OS X or Windows. After this tutorial, you will have the necessary knowledge to start the Playback tutorials. 0. 0`. Unfortunately the displayed stream has a very low framerate, it feels like maybe 3 frames per second. This is slightly complicated in GStreamer since every elements needs to be aware of the playback rate. Option 2. Enter the total length of the video in hours, minutes, and seconds. With . 0 represents twice the normal speed of the media, for example. flip = 0. I have also tried the PlayMoviesDemo from Psychtoolbox, and the issue is the same. Next, you'll want to create the different elements using How can I adjust playback speed in gstreamer's playbin to some value other than 1. 1. In its simplest form, a PIPELINE-DESCRIPTION is a list of elements separated by exclamation marks (!). 5 Parse single command interactive: Ok. 6. mkv" At the same time, I implemented a GTK app to playback this recording file using gcc basic-tutorial-12. Even though C is not an Object-Oriented (OO) language per se, the GStreamer framework uses GObject s, so some knowledge of OO concepts will come in handy. h> to do that. Perhaps you want dropping data on the PI. 10. frame_height = 360. 75, 1. Playback tutorial 7: Custom playbin sinks. A client connection over SRT to the server with URI srt://127. Mar 2, 2021 · Overview. Drain implementation here first calls decoder finish which sends a stop command to decoder and closes the task loop. Setting pipeline to PAUSED Pipeline is PREROLLING Pipeline is PREROLLED Setting pipeline to PLAYING Jun 9, 2015 · However in current versions of VLC this causes the video to not playback as data "arrives" late. 09 (debian) And also HD MPEG4 is slower ( x0. See the calculated time. 0 -vvv -e avfvideosrc device-index=0 ! x264enc bitrate=1500 speed-preset=ultrafast tune=zerolatency key-int-max=15 ! video/x-h264,profile=constrained-baseline,stream-format=avc ! matroskamux ! filesink location="test. Contributor III Mark as New; Bookmark; Subscribe; Mute; Feb 11, 2014 · Hi Leonardo, I'll test it with gplay and report back. hase March 6, 2017, 4:22am #1. 1, -0. Feb 13, 2014 · Problem with playback speed using Gstreamer Jump to solution ‎02-10-2014 03:52 PM. Receiver client. twice the speed (minus the time necessary to grab a frame). 3,246 Views jimheath. 5, 2. 5)on Linaro LInux 16. Playbin provides a stand-alone everything-in-one abstraction for an audio and/or video player. MX6DL platform with the fsl-image-qt5, forward and reverse playing at various speeds works fine. movie in the background to reduce gaps between movies. 10 which has packages ready for libx265. Overview[ edit source] gst-play (gst-play-1. 0) is a GStreamer command line utility available with GStreamer-1. When implementing single frame stepping as detailed in: Basic tutorial 13: Playback speed - GStreamer SDK documentation - GStreamer SDK documentation. X. Generic/Bin/Sink. modifications in output_gstreamer_play ensure, that no empty URIs are passed to the gstreamer, which leads to problems with bluealsa hzeller#202: prepare_next_stream as Dec 13, 2023 · Instant rate let you change the playback rate without issuing a seek, so without resetting the pipeline. It will produce a perfect stream that matches the source pad's framerate. If you need help to run this code, refer to the Running the tutorials section for your platform: Mac OS X, Windows, for iOS or for android. . GStreamer provides two mechanisms to change the playback rate: Step Aug 8, 2019 · 1. 1. Products Support DragonBoard410c. 0 is not allowed (but is equivalent to PAUSING the pipeline). 0. See gst-inspect-1. 18, which was released around GStreamer 1. GStreamer provides two mechanisms机制 to change the playback rate This tutorial shows the rest of the basic concepts required to use GStreamer, which allow building the pipeline "on the fly", as information becomes available, instead of having a monolithic pipeline defined at the beginning of your application. Then MPEG-TS demuxer and video decoder is used to get a decompressed video, that goes to a playback plugin autovideosink. 000000 seconds duration, 60. Where do I get Yocto for the Nitrogen6X board? Thanks, Jim I get the following error: (basic-tutorial-13:3117): GStreamer-CRITICAL **: gst_segment_do_seek: assertion `segment->format == format' failed There is this note on the tutorial's web page - "Changing the playback rate might only work with local files". Description. Makes a connection to an RTSP server and read the data. Convenience sink for multiple streams. This is the case where one is reading media from a file and playing it back in a synchronized fashion. Thanks in advance. 1 compiled from source on Ubuntu 15. Playback tutorial 4: Progressive streaming. Knowledge of the GObject and GLib libraries is not mandatory, but will make the Feb 6, 2017 · Figure 1: The slow, naive method to read frames from a video file using Python and OpenCV. Dec 3, 2015 · class="nav-category mobile-label ">MCUX SDK DevelopmentMCUX SDK Development All these techniques do is change the playback rate, which is a variable equal to 1. 0` If you need help to run this code, refer to the Running the tutorials section for your platform: [Mac OS X], [Windows][1], for [iOS] or for [android]. Jun 6, 2014 · Here, I put 15 ms, so this example will play a 30 fps video at approx. See the Playback tutorials for more details. During this talk, we will go over how those new features came to be, and how they have a profound impact on the resulting “Quality of Jun 27, 2017 · gstreamer pipeline to playback mp4 file on windows. 0 v4l2src device=/dev/video0 ! videorate ! video/x-raw,format=I420,width=1920,height=1080,framerate=25/1 ! xvimagesink. But as far as I understand it is dropping frames to adjust speed. audioresample resamples raw audio buffers to different sample rates using a configurable windowing function to enhance quality. I need to write a video client able to stream data from an RTSP source using GStreamer. Apr 10, 2022 · I read that gstreamer is the best way to stream the frames, although i will need a decoder on the receiving end of the stream. I tried using playbin and everything works fine. rtspsrc. time, audio samples, video frames or bytes), optionally a set of seeking-related flags (e. / # Notice you can do this even on PLAYING state. 3,254 Views jimheath. May 26, 2020 · The same result with X11: gst-launch-1. May 26, 2018 · The problem is that I want to use Playbin but the video speed is too fast when I use it. Values higher than 1. 0 with a usb camera, pipeline works fine with all USB ports execpt the high speed one. 10 but not 1. 0 filesrc location="output. c -o playback-tutorial-7 `pkg-config --cflags --libs gstreamer-1. This repo provides: a few Python examples. ' is encountered but nothing happens. 0 is normal playback speed, positive values bigger than 1. 0 ximagesrc use-damage=0 ! videoconvert ! avimux ! filesink location=out. Also, make sure that the application includes gst/gst. 0 (in absolute value) for slow modes, positive for forward playback and negative for reverse playback. Specify the playback speed for which you want to calculate the total time (e. subtitleoverlay. The Seek event has been demonstrated in the GStreamer Basic tutorial 04--time management, using a helper function to hide complexity. [Q1] Could you let me know how much accuracy can gstreamer adjust a video playback speed? [Q2] Could you let me know how to adjust a video playback speed? Best Regards, Oct 15, 2021 · Option 1. By default the element will simply negotiate the same framerate on its Feb 11, 2014 · Problem with playback speed using Gstreamer Jump to solution ‎02-10-2014 03:52 PM. The following command loads a video file and a subtitle and starts playing at the position specified in media-start (nanoseconds): All these techniques do is change the playback rate, which is a variable equal to 1. sink. 20) During rewind, bufferpool flush is called then decoder drain. 25, or 0. If I use the pipeline: self. I am able to play that mp4 video file, But i am not able to seek This plays the first 2 seconds of the file in /tmp/myfile. URI syntax is srt://<ip>:<port>. Its parameters are, basically, the new rate, the new start position and the new stop position. 0 seg-faults for some reason) using this pipeline also gives 10. x API and can be found here: Feb 19, 2021 · This is one concrete usage example of the GStreamer Daemon along with a Python Application. automatic file type recognition and based on that automatic selection and usage of the right audio/video/subtitle demuxers/decoders. raw ! audio/x-mulaw, rate=8000, channels=1 ! mulawdec ! audioconvert ! audioresample ! autoaudiosink. You can enter any value there up to 0,01 precision. A playback speed of 0. playsink. Seek event, you can jump to any place and you can set the playback speed (positive reverse). 0" ), it goes to that timestamp and starts the playback as expected. rtpopuspay encapsulates Opus-encoded audio data into RTP packets following the payload format described in RFC 7587. It takes as an input either individual files, URLs or a whole directories (in this case it will recurse into sub-directories as well). A seek-event contains a playback rate, a seek offset format (which is the unit of the offsets to follow, e. In this case, the application uses the Javascript GSTD API to communicate with GStreamer Daemon through the HTTP server. 0 is a tool that builds and runs basic GStreamer pipelines. Playback tutorial 1: Playbin usage. Pad Templates. GStreamer is a powerful library for manipulating audio and video - including live streams. 0 mp4 decode pipeline on a Sabre i. / # And now go Mar 7, 2024 · I’m observing a failure with speed based rewind (seek rate: -2) with v4l2 decoder plugin (v 1. Properties may be appended to elements in the form property=value. 265 support in gstreamer nowadays. If I create a simple pipeline to read an mkv file into a fakesink, it will run as fast as the machine can read and process the file: $ time gst-launch-1. pipeline = f"rtspsrc location={self. 0 filesrc location=interlocutor2. Playbin can handle both audio and video files and features. I modified the tutorial code as suggested to use a local file (which is attached to this bug I dumped raw RTP payload in mu-law format into a file and feeded this file into gstreamer like this: gst-launch-1. In Tools > Preferences > All > Input / Codecs you can find an option for Playback Speed. speed-preset “speed-preset” GstX265SpeedPreset * Preset name for speed/quality tradeoff options. ACTUAL RESULT: pitch goes up/down. The number of subtitle streams is shown in the terminal, and the user can switch from one to another by entering a number and pressing enter. edu being a big target for Gnome and Linux, I wonder if there could also be an alternative UI (mode) specifically aimed at playing back language study audio etc. Playback tutorial 8: Hardware-accelerated video decoding. gcc playback-tutorial-3. 0 tcpserversink for options of buffers here ( buffers-max for example). 0 and 1. One of the seek parameter is the playback rate, issueing a seek dispatches the new rate to the pipeline. GStreamer command-line cheat sheet. Finally the player gets killed. 3 It looks like a gstreamer plugin is missing which should do the pitchcompensation in the gstreamer pipeline. Warning. Lets change the playback speed, first lets make it go slower: / # gst-client -p 1 speed 0. 83 using:ffprobe or vlc (though on my version of gstreamer, gst-discoverer-1. ffmpeg on the other hand is better suited to playback real-time data with low latency. In this case, multiple streams need to be synchronized, like May 25, 2020 · gstreamer+x11+imx (bad, too fast playback) - YouTube Has anybody idea, why value of setted FPS affects the playback speed of the result file? There is no problems on x86_64 with same commands. See this bug of GStreamer. c -o playback-tutorial-4 `pkg-config --cflags --libs gstreamer-1. Use #include <gst/gst. MX6DQ gstreamer in L3. One pipeline is used to produce a test pattern, do H264 encoding, wrap it in an MPEG transport stream and then write it to a file. This element has been extensively used throughout the tutorials. PlayMoviesWithoutGapDemo2 – GStreamer only: Optimized version of gap-less playback. extra playback options (SKIP) a format to seek in, this can be time, bytes, units (frames, samples), … a playback rate, 1. This ensures that the table does not become too big. 15. GStreamer provides two mechanisms to change the playback rate: Step And the answer was found using a gstreamer plugin named gnonlin. Check the bindings release notes for details of the changes since 0. Please see their questions as following. It has a pipeline-based architecture, which allows to freely configure the data flow across a variety of plugins that handle different data formats. And then decoder flush is called which does streamoff on the driver. Note however this probably results in a broken bit stream. Playback tutorial 3: Short-cutting the pipeline. But it playbacks too fast. All these techniques do is change the playback rate, which is a variable equal to 1. whether internal buffers should be flushed), a seek method (which indicates relative to what the offset was given), and seek offsets. The playback speed of Full HD MPEG4 is slower ( x0. import time. Playback tutorial 6: Audio visualization. turn the 2 second long gnlfilesource into an infinite length video that plays those 2 seconds again and again and again? Aug 20, 2014 · Hi Satoshi Shimoda, Sorry for the delay I got distracted on a project. import cv2. here is the pipeline: The tutorials are currently written only in the C programming language, so you need to be comfortable with it. Adding "framerate=20/1" to the caps throws "Not negotiated error" while setting it to "30/1" works Thread: [Gstreamer-bugs] [Bug 123815] New - Wishlist: Variable-speed playback on any stream Status: Beta Brought to you by: bilboed , ensonic , theuraeus , thomasvs , and 2 others Mar 6, 2017 · Gstreamer issue of DragonBoard 410c - DragonBoard410c - 96Boards Forum. 1, Encoder There is x265enc which will be enabled when we have library libx265-dev. Mar 9, 2023 · I am facing some issues when using the HS USB3. PlayInterlacedMovieDemo – Simple demo on how to use the GLSL realtime video deinterlacer. c -o basic-tutorial-12 `pkg-config --cflags --libs gstreamer-1. 0` If you need help to run this code, refer to the Running the tutorials section for your platform: Mac OS X, Windows, for iOS or for android. The up/down buttons on the right change the playback speed in 0,10 increments. The encoder is inside gst-plugins Jan 30, 2012 · It rewinds for a small duration and then the playback stops. This component includes several gstreamer elements including gnlfilesource which can start the video at a specific position. gcc playback-tutorial-7. The point is that I need to fine tune the latency [ request for comments ] seek problem and playback speed too fast. This element takes an incoming stream of timestamped video frames. Note that multiple clients can The media is fetched from the Internet, so the window might take a few seconds to appear, depending on your connection speed. 0-ga. ! v4l2sink device=/dev/video0". The application consists of a Simple Video Player with several capabilities: Select the input (Camera or video file) Regular and reverse video playback. If I just seek backwards with certain duration (rate is "1. 0+git. This is running on a TI 8148 EVM. audioresample. 0, indicating that the media is playing at the standard speed. I would like to increase playback speed like 2x. Video/Overlay/Subtitle. GStreamer is an open-source multimedia framework written in C using the GObject framework. 349786b46e61 #1 SMP PREEMPT Wed Dec 28 09:58:45 UTC 2022 aarch64 aarch64 aarch64 GNU/Linux. It is so flexible and has so many options that a whole set of tutorials are devoted to it. avi gstreamer+x11+imx (bad, too fast playback) - YouTube Has anybody idea, why value of setted FPS affects the playback speed of the result file? There is no problems on x86 Sep 13, 2015 · A little late but, maybe some people will find this question when seeking info about H. 77-6. 0 represents normal speed, while 2. 5, 1. PlayMoviesWithoutGapDemo1 – Play one movie while opening another one for gap-less playback. In addition to the RFC, which assumes only mono and stereo payload, the element supports multichannel Opus audio streams using a non-standardized SDP config and "MULTIOPUS" codec developed by Google for libwebrtc. Hi, I am trying to record an incoming live stream into mp4 format. c -o playback-tutorial-1 `pkg-config --cflags --libs gstreamer-1. py. RTSP supports transport over TCP or UDP in unicast or multicast mode. Kirill Jan 23, 2023 · The GStreamer Rust bindings are released separately with a different release cadence that's tied to gtk-rs, but the latest release has already been updated for the new GStreamer 1. Also, I am probably decoding more frames than the number my application can actually consumes. In this case, the application uses the Python GSTD API to communicate with GStreamer Daemon. GStreamer provides two mechanisms to change the playback rate: Step May 8, 2017 · I am going through the GStreamer Basic tutorial 13: Playback speed. 0 mean fast playback. 0 will increase the playback speed, while values between 0. 5). [droppedframes] = Screen (‘PlayMovie’, moviePtr, rate, [loop], [soundvolume]); Start playback of movie associated with movieobject ‘moviePtr’. 21. 9). I configured VLC to stream a video I have on my laptop using RTSP and I want to create a pipeline to get that stream and show it. The gstd is very similar to the gst-launch command line but a little bit more 1 day ago · 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 FS#62557 - [gstreamer] totem video crash when change playback speed Attached to Project: Arch Linux Opened by Andrea (Dea1993) - Monday, 06 May 2019, 07:16 GMT Nov 5, 2023 · A 4K HDR video at 60 fps (DevilMayCry5. 2, 1. Linux apalis-imx8-06804745 5. 0 (in absolute value) for fast modes, lower than 1. mkv ! matroskademux ! fakesink. Dec 12, 2023 · Hi, I have a pipeline that decodes from a 4K 25fps mp4 file. I tested it with "2x" and "4x" speed. GStreamer provides two mechanisms機制 to change the playback rate Autoplug and play media from an uri. If I use this pipeline. e. This is with gstreamer 1. Now you should be watching the video you record at a normal speed. I've followed most of the tutorials on the gstreamer website but the only thing that is not working is the playback speed. This property holds the playback rate of the current media. Additionally, in the „Time Saved” field, you can also see how much time can you gain or lose while watching the video or listening to the Feb 24, 2022 · 720p hardware decoder failed, no jitter (all 4 cores of CPU running at about 30%) 1080p hardware decoder failed, jitter (dropped frames) (all 4 cores of CPU running at about 60%) I also tried using chewie controller and standard video_player controller and same gstreamer-critical errors occur and video controls don't function. url} latency=10 ! rtph264depay ! h264parse ! avdec_h264 ! videoconvert ! appsink max-buffers=1 drop=true". Hi,This is a big issue of Gstreamer. Mar 24, 2015 · Hi everyone I am trying to change the playback speed of an audio file using the gstreamer library in c. Although I think I grasp it, I am confused by the following sentence (my bold) in the explanation of the send_seek_event code: The Seek Event is created with gst_event_new_seek(). Apr 29, 2024 · Hello, I’m recording live stream from webcam into file sink (H. Playback tutorial 2: Subtitle management. negative values mean reverse playback. Not supported on the GStreamer (Unix) backend. A small delay is to be expected. By default rtspsrc will negotiate a connection in the following order: UDP unicast/UDP multicast/TCP. 264/. mp4 file in the drive folder) cannot be played in real-time (the frames are not dropped). gst-launch-1. 5 (backward) speed of normal without loosing sound if possible. Another option, if you really want control about how and what you grab from video files, is to use the GStreamer API to grab the images, and then convert to OpenCV for image tratment. Nov 17, 2020 · 0. This utility plays multimedia content using the Playbin element as a basic player. Multimedia processing in GStreamer is done by connecting several elements into a pipeline. How can I adjust playback speed in gstreamer's playbin to some value other than 1. aq hb uk ik wi sc yn nz mn zo