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• Anomalie #2773 (Nouveau) : Boucle recherche Forum : mauvaise selection avec le critère {tout}

  24 juin 2012, par Hossein ROTY

  Le résultat d’une recherche dans les forums est différent selon que l’on emploie le critère plat ou le critère tout. Alors que le critère plat sélectionne correctement les messages contenant l’occurence recherchée, le critère tout sélectionne le premier message du thread et non la réponse à ce message (...)

• FFmpeg/libav Storing AVPacket data in a file and decoding them again in a different stream - How to prepare and send custom packets in the decoder ?

  21 avril 2022, par Hitokage

  I want to be able to open a stream with a video file and send in the decoder my own packets with data that I previously stored from a different stream with the same codec. So like forging my own packets in the decoder.

  


  My approach is that I encode frames into packets using H.265 and store the data in a file like this :

  


  AVPacket *packet;
std::vector data;
...encoding...
data->insert(data->end(), &packet->data[0], &packet->data[packet->size]);
...storing the buffer in a file...


  


  I also have one mkv video with H.265 stream of the same parameters. Now I want to get the stored packet data in the file, create a new packet, and send it into the decoding process of the mkv file. To make it easier I just copy the parameters of the first packet in the mkv stream into a new packet where I insert my data and send it to the decoder. Is this a right approach ?

  


  ...open decoder with mkv file...
auto packet = av_packet_alloc();
av_read_frame(formatContext, packet);
//here is the packet I will use later with my data
av_packet_copy_props(decodingPacket, packet);
decodingPacket->flags = 0;
//sending the packet from the mkv
avcodec_send_packet(codecContext, packet);
//the data contains the previously stored data
av_packet_from_data(decodingPacket, data.data(), data.size());
avcodec_send_packet(codecContext, decodingPacket);
...retrieving the frame...


  


  However, I am getting this error when I try to send the forget packet :

  


  Assertion buf_size >= 0 failed at libavcodec/bytestream.h:141


  


  I have tried to manually change the decodingPacket->buf->size but that is probably not the problem. I believe that I need to set up some other parameters in the forged packet but what exactly ? Maybe I can also somehow store not only the packet data but the whole structure ? Please let me know, if there is a better way to store and reload a packet and force it into an unrelated decoder with the same parameters.
Thanks !

  


  EDIT : Seems like the buf_size problem was related to my data which were wrongly retrieved. I can confirm that this works now but I am getting a new error :

  


  [hevc @ 0x559b931606c0] Invalid NAL unit size (0 > 414).
[hevc @ 0x559b931606c0] Error splitting the input into NAL units.


  


• Anomalie #4468 : CSS colonne gauche du privé

  4 avril 2020

  Et même à la réflexion, pour les boutons d’actions prendre un gris neutre au lieu de la couleur utilisateur (qui pique un peu les yeux des fois), pleine largeur et centrer le texte (si dans une colonne).