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• Perspective transformations

  4 février 2009, par Mikko Koppanen — Imagick, PHP stuff

  Finally (after a long break) I managed to force myself to update the PHP documentation and this time it was distortImage code example. Things have been hectic lately but that does not quite explain the 6 months(?) break between this and the previous post. As a matter of a fact there is no excuse for such a long silence so I will try to update this blog a bit more often from now on.

  Back in the day I used to blog the examples and update the documentation if I remembered but I am trying to fix this bad habit. Most of the latest examples have been updated in to the manual. In the case of the two last examples I updated the documentation first and then blogged on the subject.

  I took some time to actually understand the perspective transformations properly using the excellent ImageMagick examples (mainly created by Anthony Thyssen) as a reference. The basic idea of perspective distortion seems simple : to distort the control points to new locations. Grabbing the syntax for Imagick was easy, an array of control point pairs in the form of :

  php

  < view plain text >

  1. array(source_x, source_y, dest_x, dest_y ... )

  The following example uses the built-in checkerboard pattern to demonstrate perspective distortion :

  php

  < view plain text >

  1. < ?php
  2. /* Create new object */
  3. $im = new Imagick() ;
  4.  
  5. /* Create new checkerboard pattern */
  6. $im->newPseudoImage(100, 100, "pattern:checkerboard") ;
  7.  
  8. /* Set the image format to png */
  9. $im->setImageFormat(’png’) ;
  10.  
  11. /* Fill background area with transparent */
  12. $im->setImageVirtualPixelMethod(Imagick: :VIRTUALPIXELMETHOD_TRANSPARENT) ;
  13.  
  14. /* Activate matte */
  15. $im->setImageMatte(true) ;
  16.  
  17. /* Control points for the distortion */
  18. $controlPoints = array( 10, 10,
  19.             10, 5,
  20.  
  21.             10, $im->getImageHeight() - 20,
  22.             10, $im->getImageHeight() - 5,
  23.  
  24.             $im->getImageWidth() - 10, 10,
  25.             $im->getImageWidth() - 10, 20,
  26.  
  27.             $im->getImageWidth() - 10, $im->getImageHeight() - 10,
  28.             $im->getImageWidth() - 10, $im->getImageHeight() - 30) ;
  29.  
  30. /* Perform the distortion */ 
  31. $im->distortImage(Imagick: :DISTORTION_PERSPECTIVE, $controlPoints, true) ;
  32.  
  33. /* Ouput the image */ 
  34. header("Content-Type : image/png") ;
  35. echo $im ;
  36.  ?>

  Here is the source image :
  

  And the result :
  

• Revision 7563dd4a8d : vp9 dec/com : only update frame counts when necessary don't update them when fra

  16 octobre 2013, par James Zern

  Changed Paths :
   Modify /vp9/common/vp9_entropymv.c

  
   Modify /vp9/decoder/vp9_decodemv.c

  
   Modify /vp9/decoder/vp9_decodframe.c

  
   Modify /vp9/decoder/vp9_detokenize.c

  
  
  vp9 dec/com : only update frame counts when necessary

  don't update them when frame_parallel_mode is true

  Change-Id : I22ff131a6c6eea238415d10b729f195c7d6dc60d

• Live555 : X264 Stream Live source based on "testOnDemandRTSPServer"

  12 janvier 2017, par user2660369

  I am trying to create a rtsp Server that streams the OpenGL output of my program. I had a look at How to write a Live555 FramedSource to allow me to stream H.264 live, but I need the stream to be unicast. So I had a look at testOnDemandRTSPServer. Using the same Code fails. To my understanding I need to provide memory in which I store my h264 frames so the OnDemandServer can read them on Demand.

  H264VideoStreamServerMediaSubsession.cpp

  H264VideoStreamServerMediaSubsession*
  
  H264VideoStreamServerMediaSubsession::createNew(UsageEnvironment& env,
  
                            Boolean reuseFirstSource) {
  
    return new H264VideoStreamServerMediaSubsession(env, reuseFirstSource);
  
  }
  
  
  
  H264VideoStreamServerMediaSubsession::H264VideoStreamServerMediaSubsession(UsageEnvironment& env, Boolean reuseFirstSource)
  
    : OnDemandServerMediaSubsession(env, reuseFirstSource), fAuxSDPLine(NULL), fDoneFlag(0), fDummyRTPSink(NULL) {
  
  }
  
  
  
  H264VideoStreamServerMediaSubsession::~H264VideoStreamServerMediaSubsession() {
  
    delete[] fAuxSDPLine;
  
  }
  
  
  
  static void afterPlayingDummy(void* clientData) {
  
    H264VideoStreamServerMediaSubsession* subsess = (H264VideoStreamServerMediaSubsession*)clientData;
  
    subsess->afterPlayingDummy1();
  
  }
  
  
  
  void H264VideoStreamServerMediaSubsession::afterPlayingDummy1() {
  
    // Unschedule any pending 'checking' task:
  
    envir().taskScheduler().unscheduleDelayedTask(nextTask());
  
    // Signal the event loop that we're done:
  
    setDoneFlag();
  
  }
  
  
  
  static void checkForAuxSDPLine(void* clientData) {
  
    H264VideoStreamServerMediaSubsession* subsess = (H264VideoStreamServerMediaSubsession*)clientData;
  
    subsess->checkForAuxSDPLine1();
  
  }
  
  
  
  void H264VideoStreamServerMediaSubsession::checkForAuxSDPLine1() {
  
    char const* dasl;
  
  
  
    if (fAuxSDPLine != NULL) {
  
      // Signal the event loop that we're done:
  
      setDoneFlag();
  
    } else if (fDummyRTPSink != NULL && (dasl = fDummyRTPSink->auxSDPLine()) != NULL) {
  
      fAuxSDPLine = strDup(dasl);
  
      fDummyRTPSink = NULL;
  
  
  
      // Signal the event loop that we're done:
  
      setDoneFlag();
  
    } else {
  
      // try again after a brief delay:
  
      int uSecsToDelay = 100000; // 100 ms
  
      nextTask() = envir().taskScheduler().scheduleDelayedTask(uSecsToDelay,
  
                    (TaskFunc*)checkForAuxSDPLine, this);
  
    }
  
  }
  
  
  
  char const* H264VideoStreamServerMediaSubsession::getAuxSDPLine(RTPSink* rtpSink, FramedSource* inputSource) {
  
    if (fAuxSDPLine != NULL) return fAuxSDPLine; // it's already been set up (for a previous client)
  
  
  
    if (fDummyRTPSink == NULL) { // we're not already setting it up for another, concurrent stream
  
      // Note: For H264 video files, the 'config' information ("profile-level-id" and "sprop-parameter-sets") isn't known
  
      // until we start reading the file.  This means that "rtpSink"s "auxSDPLine()" will be NULL initially,
  
      // and we need to start reading data from our file until this changes.
  
      fDummyRTPSink = rtpSink;
  
  
  
      // Start reading the file:
  
      fDummyRTPSink->startPlaying(*inputSource, afterPlayingDummy, this);
  
  
  
      // Check whether the sink's 'auxSDPLine()' is ready:
  
      checkForAuxSDPLine(this);
  
    }
  
  
  
    envir().taskScheduler().doEventLoop(&fDoneFlag);
  
  
  
    return fAuxSDPLine;
  
  }
  
  
  
  FramedSource* H264VideoStreamServerMediaSubsession::createNewStreamSource(unsigned /*clientSessionId*/, unsigned& estBitrate) {
  
    estBitrate = 500; // kb
  
    megamol::remotecontrol::View3D_MRC *parent = (megamol::remotecontrol::View3D_MRC*)this->parent;
  
    return H264VideoStreamFramer::createNew(envir(), parent->h264FramedSource);
  
  }
  
  
  
  RTPSink* H264VideoStreamServerMediaSubsession::createNewRTPSink(Groupsock* rtpGroupsock, unsigned char rtpPayloadTypeIfDynamic, FramedSource* /*inputSource*/) {
  
    return H264VideoRTPSink::createNew(envir(), rtpGroupsock, rtpPayloadTypeIfDynamic);
  
  }

  FramedSource.cpp

  H264FramedSource* H264FramedSource::createNew(UsageEnvironment& env,
  
                                            unsigned preferredFrameSize,
  
                                            unsigned playTimePerFrame)
  
  {
  
      return new H264FramedSource(env, preferredFrameSize, playTimePerFrame);
  
  }
  
  
  
  H264FramedSource::H264FramedSource(UsageEnvironment& env,
  
                                 unsigned preferredFrameSize,
  
                                 unsigned playTimePerFrame)
  
      : FramedSource(env),
  
      fPreferredFrameSize(fMaxSize),
  
      fPlayTimePerFrame(playTimePerFrame),
  
      fLastPlayTime(0),
  
      fCurIndex(0)
  
  {
  
  
  
      x264_param_default_preset(&param, "veryfast", "zerolatency");
  
      param.i_threads = 1;
  
      param.i_width = 1024;
  
      param.i_height = 768;
  
      param.i_fps_num = 30;
  
      param.i_fps_den = 1;
  
      // Intra refres:
  
      param.i_keyint_max = 60;
  
      param.b_intra_refresh = 1;
  
      //Rate control:
  
      param.rc.i_rc_method = X264_RC_CRF;
  
      param.rc.f_rf_constant = 25;
  
      param.rc.f_rf_constant_max = 35;
  
      param.i_sps_id = 7;
  
      //For streaming:
  
      param.b_repeat_headers = 1;
  
      param.b_annexb = 1;
  
      x264_param_apply_profile(&param, "baseline");
  
  
  
      param.i_log_level = X264_LOG_ERROR;
  
  
  
      encoder = x264_encoder_open(&param);
  
      pic_in.i_type            = X264_TYPE_AUTO;
  
      pic_in.i_qpplus1         = 0;
  
      pic_in.img.i_csp         = X264_CSP_I420;
  
      pic_in.img.i_plane       = 3;
  
  
  
  
  
      x264_picture_alloc(&pic_in, X264_CSP_I420, 1024, 768);
  
  
  
      convertCtx = sws_getContext(1024, 768, PIX_FMT_RGBA, 1024, 768, PIX_FMT_YUV420P, SWS_FAST_BILINEAR, NULL, NULL, NULL);
  
      eventTriggerId = envir().taskScheduler().createEventTrigger(deliverFrame0);
  
  }
  
  
  
  H264FramedSource::~H264FramedSource()
  
  {
  
      envir().taskScheduler().deleteEventTrigger(eventTriggerId);
  
      eventTriggerId = 0;
  
  }
  
  
  
  void H264FramedSource::AddToBuffer(uint8_t* buf, int surfaceSizeInBytes)
  
  {
  
      uint8_t* surfaceData = (new uint8_t[surfaceSizeInBytes]);
  
  
  
      memcpy(surfaceData, buf, surfaceSizeInBytes);
  
  
  
      int srcstride = 1024*4;
  
      sws_scale(convertCtx, &surfaceData, &srcstride,0, 768, pic_in.img.plane, pic_in.img.i_stride);
  
      x264_nal_t* nals = NULL;
  
      int i_nals = 0;
  
      int frame_size = -1;
  
  
  
  
  
      frame_size = x264_encoder_encode(encoder, &nals, &i_nals, &pic_in, &pic_out);
  
  
  
      static bool finished = false;
  
  
  
      if (frame_size >= 0)
  
      {
  
      static bool alreadydone = false;
  
      if(!alreadydone)
  
      {
  
  
  
          x264_encoder_headers(encoder, &nals, &i_nals);
  
          alreadydone = true;
  
      }
  
      for(int i = 0; i < i_nals; ++i)
  
      {
  
          m_queue.push(nals[i]);
  
      }
  
      }
  
      delete [] surfaceData;
  
      surfaceData = nullptr;
  
  
  
      envir().taskScheduler().triggerEvent(eventTriggerId, this);
  
  }
  
  
  
  void H264FramedSource::doGetNextFrame()
  
  {
  
      deliverFrame();
  
  }
  
  
  
  void H264FramedSource::deliverFrame0(void* clientData)
  
  {
  
      ((H264FramedSource*)clientData)->deliverFrame();
  
  }
  
  
  
  void H264FramedSource::deliverFrame()
  
  {
  
      x264_nal_t nalToDeliver;
  
  
  
      if (fPlayTimePerFrame > 0 && fPreferredFrameSize > 0) {
  
      if (fPresentationTime.tv_sec == 0 && fPresentationTime.tv_usec == 0) {
  
          // This is the first frame, so use the current time:
  
          gettimeofday(&fPresentationTime, NULL);
  
      } else {
  
          // Increment by the play time of the previous data:
  
          unsigned uSeconds   = fPresentationTime.tv_usec + fLastPlayTime;
  
          fPresentationTime.tv_sec += uSeconds/1000000;
  
          fPresentationTime.tv_usec = uSeconds%1000000;
  
      }
  
  
  
      // Remember the play time of this data:
  
      fLastPlayTime = (fPlayTimePerFrame*fFrameSize)/fPreferredFrameSize;
  
      fDurationInMicroseconds = fLastPlayTime;
  
      } else {
  
      // We don't know a specific play time duration for this data,
  
      // so just record the current time as being the 'presentation time':
  
      gettimeofday(&fPresentationTime, NULL);
  
      }
  
  
  
      if(!m_queue.empty())
  
      {
  
      m_queue.wait_and_pop(nalToDeliver);
  
  
  
      uint8_t* newFrameDataStart = (uint8_t*)0xD15EA5E;
  
  
  
      newFrameDataStart = (uint8_t*)(nalToDeliver.p_payload);
  
      unsigned newFrameSize = nalToDeliver.i_payload;
  
  
  
      // Deliver the data here:
  
      if (newFrameSize > fMaxSize) {
  
          fFrameSize = fMaxSize;
  
          fNumTruncatedBytes = newFrameSize - fMaxSize;
  
      }
  
      else {
  
          fFrameSize = newFrameSize;
  
      }
  
  
  
      memcpy(fTo, nalToDeliver.p_payload, nalToDeliver.i_payload);
  
  
  
      FramedSource::afterGetting(this);
  
      }
  
  }

  Relevant part of the RTSP-Server Therad

    RTSPServer* rtspServer = RTSPServer::createNew(*(parent->env), 8554, NULL);
  
    if (rtspServer == NULL) {
  
      *(parent->env) << "Failed to create RTSP server: " << (parent->env)->getResultMsg() << "\n";
  
      exit(1);
  
    }
  
    char const* streamName = "Stream";
  
    parent->h264FramedSource = H264FramedSource::createNew(*(parent->env), 0, 0);
  
    H264VideoStreamServerMediaSubsession *h264VideoStreamServerMediaSubsession = H264VideoStreamServerMediaSubsession::createNew(*(parent->env), true);
  
    h264VideoStreamServerMediaSubsession->parent = parent;
  
    sms->addSubsession(h264VideoStreamServerMediaSubsession);
  
    rtspServer->addServerMediaSession(sms);
  
  
  
    parent->env->taskScheduler().doEventLoop(); // does not return

  Once a connection exists the render loop calls

  h264FramedSource->AddToBuffer(videoData, 1024*768*4);