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• In what way does this HEVC video not comply to Apples's requirements document ?

  16 novembre 2022, par Duke Dougal

  My goal is to work out why a given video file does not play on Macos/Safari/Quicktime.

  


  The background to this question is that it is possible to play HEVC videos with a transparent background/alpha channel on Safari/MacOS. To be playable, a video must meet the specific requirements set out by Apple in this document :

  


  https://developer.apple.com/av-foundation/HEVC-Video-with-Alpha-Interoperability-Profile.pdf

  


  The video that does not play on Apple/Safari/Quicktime is an HEVC video with an alpha transparency channel. Note that VLC for MacOS DOES play this file. Here it is :

  


  https://drive.google.com/file/d/1ZnXjcDbk-_YxTgRuH_D7RSR9SXdY_XTv/view?usp=share_link

  


  I have two example HEVC video files with a transparent background/alpha channel, and they both play fine using either Quicktime player or Safari :

  


  Working video #1 :

  


  https://drive.google.com/file/d/1PJAyg_sVKVvb-Py8PAu42c1qm8l2qCbh/view?usp=share_link

  


  Working video #2 :

  


  https://drive.google.com/file/d/1kk8ssUyT7qAaK15afp8VPR6mIWPFX8vQ/view?usp=sharing

  


  The first step is to work out in what way my non-working video ( https://drive.google.com/file/d/1ZnXjcDbk-_YxTgRuH_D7RSR9SXdY_XTv/view?usp=share_link ) does not comply with the specification.

  


  Once it is clear which requirements are not met by the non-working video then I can move onto the next phase, which is to try to formulate an ffmpeg command that will output a video meeting the requirements.

  


  I have read Apples requirements document and I am out of my depth in trying to analyse the non working video against the requirements - I don't know how to do it.

  


  Can anyone suggest a way to identify what is wrong with the video ?

  


  Additional context is that I am trying to find a way to create Apple/MacOS compatible alpha channel / transparent videos using ffmpeg with hevc_nvenc running on an Intel machine. I am aware that Apple hardware can create such videos, but for a wide variety of reasons it is not practical for me to use Apple hardware to do the job. I have spent many hours trying all sorts of ffmpeg and ffprobe commands to try to work out what is wrong and modify the video to fix it, but to be honest most of my attempts are guesswork.

  


• What libraries needed to link FFMPEG in ubuntu 64bit ?

  12 mai 2016, par mofed8461

  After compile FFMPEG, and use it in my project, what system libraries do i need to link in order to use FFMPEG in my C++ project so its not generating "undefined reference error" ?

  in Mac OS X i usually link these libraries :

  FIND_LIBRARY(LIB_Z libz.1.dylib)
  
  FIND_LIBRARY(LIB_BZ2 libbz2.1.0.dylib)
  
  FIND_LIBRARY(LIB_ICONV libiconv.2.dylib)
  
  FIND_PACKAGE(CoreVideo REQUIRED)
  
  FIND_PACKAGE(CoreMedia REQUIRED)
  
  FIND_PACKAGE(Foundation REQUIRED)
  
  FIND_PACKAGE(AVFoundation REQUIRED)
  
  FIND_PACKAGE(IOKit REQUIRED)
  
  FIND_PACKAGE(Cocoa REQUIRED)
  
  FIND_PACKAGE(Security REQUIRED)
  
  FIND_PACKAGE(CoreFoundation REQUIRED)
  
  FIND_PACKAGE(VideoDecodeAcceleration REQUIRED)
  
  FIND_PACKAGE(VideoToolbox REQUIRED)

  but in Ubuntu i don’t know what to link ?!

• create AVI file from compressed data

  3 décembre 2015, par Qureshi

  I am using ffmpeg libararies to create an AVI file as mentioned in the post (Make AVI file from H264 compressed data), this guy had the same problem as i currently have (i-e getting error value -22.

  Please anyone can explain me what’s the meaning of this error code "-22" that i get from "av_interleaved_write_frame" ?

  he suggested that "By setting pts and dts with AV_NOPTS_VALUE I’ve solved the problem." please share any example how to set pts value with AV_NOPTS_VALUE ? and what should be the value of pts any rought estimate ?