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• Using Qt Media Player on Raspberry Pi 1

  18 mai 2015, par Mauker

  I have a project built using Qt5 which has to play a video. Just like in the videowidget sample code.

  I’ve followed these instructions to build qt5 on my Pi. And it went just fine. But when I try to run any qt program that uses QMediaPlayer, I get the error message :

  defaultServiceProvider::requestService(): no service found for - "org.qt-project.qt.mediaplayer"

  Which means I don’t have a backend to play the video, right ? Is there any one that I can use which will with Qt, like ffmpeg ? And how can I get it to work ? Specially for h264 videos.

  I’ve tried to install gstreamer as is told on this link, but it’s not working. Will I have to rebuild the entire qt5 again ?

  P.S. : I have the raspberry pi 1 model B with raspbian installed.

  Edit : As mentioned by Greenflow, I checked the ./configure log and saw that the GStreamer was compiled in, but the video apps are still not working...

  The message on the log was like this :

  GStreamer .............. yes (0.10)

  And the message on Greenflow’s log was like this :

  GStreamer .............. yes (1.0)

  Clearly it’s another version of GStreamer, but is it the problem ?

  I’ve also found this post which says QtMultimedia on the Pi is rather useless, but the post is from 2013, so I’m not sure if it’s really relevant. I’d like to have this app playing hardware accelerated videos on my Raspberry Pi, but I’m almost dropping the idea.

  Anyways, thanks Greenflow for the head start.

  Edit 2 : Found this thread on the Qtcentre. Damn, this thing is not going to be easy to solve, I guess...

• avcodec/amfenc : Implement async_depth option

  7 novembre 2024, par Cameron Gutman

  avcodec/amfenc : Implement async_depth option
  This option, which is also available on other FFmpeg hardware encoders,
  
  allows the user to trade throughput for reduced output latency. This is
  
  useful for ultra low latency applications like game streaming.
  Signed-off-by : Cameron Gutman <aicommander@gmail.com>
  

  • [DH] libavcodec/amfenc.c
  • [DH] libavcodec/amfenc_av1.c
  • [DH] libavcodec/amfenc_h264.c
  • [DH] libavcodec/amfenc_hevc.c

• Playing RTP stream on Android 4.1.2 (Jelly Bean) [closed]

  27 décembre 2024, par Homie_Tomie

  I'll try to keep it quick. Using FFMPEG I started a stream on my PC. Here is the code :

  


  import subprocess

def start_stream():
    command = [
        'ffmpeg',
        '-f', 'gdigrab',  # Desktop capture (Windows)
        '-framerate', '15',  # Low framerate for higher performance
        '-i', 'desktop',  # Capture desktop
        '-c:v', 'libx264',  # Video codec (H.264)
        '-preset', 'ultrafast',  # Ultra-fast encoding preset for minimal latency
        '-tune', 'zerolatency',  # Zero latency for real-time streaming
        '-x264opts', 'keyint=15:min-keyint=15:no-scenecut',  # Frequent keyframes
        '-b:v', '500k',  # Low bitrate to minimize data usage and reduce latency
        '-s', '800x480',  # Resolution fits phone screen and helps performance
        '-max_delay', '0',  # No buffering, instant frame output
        '-flush_packets', '1',  # Flush packets immediately after encoding
        '-f', 'rtp',  # Use mpegts as the container for RTP stream
        'rtp://192.168.72.26:1234',  # Stream over UDP to localhost on port 1234
        '-sdp_file', 'stream.sdp'  # Create SDP file
    ]
    
    try:
        print("Starting stream...")
        subprocess.run(command, check=True)
    except subprocess.CalledProcessError as e:
        print(f"Error occurred: {e}")
    except KeyboardInterrupt:
        print("\nStream interrupted")

if __name__ == "__main__":
    print("Starting screen capture...")
    start_stream()


  


  Now, when I start the stream I can connect to it in VLC when I open up the stream.sdp file. Using the same method I can open up the stream on my iPhone, but when I try to open it on my old Android phone the stream connects but the screen is black. However, when I turn the screen I can see the first frame that was sent to the phone. Why does the stream not work ?

  


  I will be thankful for any and all advice :)