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• avcodec/smacker : Use unsigned for prediction values

  26 juin 2020, par Andreas Rheinhardt

  avcodec/smacker : Use unsigned for prediction values
  Up until now, the Smacker decoder has pretended that the prediction
  
  values are signed in code like 'pred[0] += (unsigned)sign_extend(val, 16)'
  
  (the cast has been added to this code later to fix undefined behaviour).
  
  This has been even done in case the PCM format is u8.
  Yet in case of 8/16 bit samples, only the lower 8/16 bit of the predicition
  
  values are ever used, so one can just as well just use unsigned and
  
  remove the sign extensions. This is what this commit does.
  For GCC 9 the time for one call to smka_decode_frame() for the sample from
  
  ticket #2425 decreased from 1709043 to 1693619 decicycles ; for Clang 9
  
  it went up from 1355273 to 1369089 decicycles.
  Reviewed-by : Paul B Mahol <onemda@gmail.com>
  
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavcodec/smacker.c

• How to send AVPacket through a QTcpSocket.write() with all of its data ?

  24 juin 2024, par CottonBuds

  I want to send an AVPacket though a QTcpSocket.write() I tried to cast the avpacket pointer to an char * but it only shows 8 bytes of the avpacket and without the avpacket.data.

  


  

  


  here is my code

  


  void DisplayStreamServer::sendDataToClient(AVPacket* packet) {
    if (client == nullptr) {
        return;
    }


    client->write((char*) packet);
    client->waitForBytesWritten();

    av_packet_unref(packet);
    av_packet_free(&packet);
}


  


  I can see that my packet.data has data inside it using the visual studio memory viewer. but it seems like when i convert the packet to char * the data is not included

  


  

  


• libavutil/hwcontext_qsv : fix a bug for mapping vaapi frame to qsv

  16 novembre 2021, par nyanmisaka

  libavutil/hwcontext_qsv : fix a bug for mapping vaapi frame to qsv
  The data stored in data[3] in VAAPI AVFrame is VASurfaceID while
  
  the data stored in pair->first is the pointer of VASurfaceID, so
  
  we need to do cast to make following commandline works :
  ffmpeg -hwaccel vaapi -hwaccel_device /dev/dri/renderD128 \
  
   hwaccel_output_format vaapi -i input.264 \
  
   vf "hwmap=derive_device=qsv,format=qsv" -c:v h264_qsv output.264
  Signed-off-by : nyanmisaka <nst799610810@gmail.com>
  
  Signed-off-by : Wenbin Chen <wenbin.chen@intel.com>
  
  Signed-off-by : Anton Khirnov <anton@khirnov.net>
  

  • [DH] libavutil/hwcontext_qsv.c