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• How to generate a PDF (1.7) from a MP4 movie (Rich Media annotation) ?

  19 août 2020, par malat

  I am a happy user of img2pdf. This tool does the minimal amount of work to put a series of JPEG 2000/JPEG/PNG images into a PDF "enveloppe". However I am now faced with a new challenge : embed a MP4 file into a PDF "enveloppe".

  


  I see that commercial tool can do it, as seen at :

  


  

  • Add audio, video, and interactive objects to PDFs

  


  


  It seems to have been introduced in ISO 32000-1 (PDF 1.7 Extension Level 5)

  


  I am looking for a solution which will use the Rich Media annotation inside the PDF stream.

  


  There are dozen of duplicated questions on superuser/stackoverflow, which all pretty much refer to imagemagick/convert command line tool. But in my case, convert expand the images into a multi-page PDF (which is not my desired behavior) :

  


  $ convert input.mp4 output.pdf
$ pdfinfo output.pdf 
Title:          out
Producer:       https://imagemagick.org
CreationDate:   Wed Aug 19 15:38:01 2020 CEST
ModDate:        Wed Aug 19 15:38:01 2020 CEST
Tagged:         no
UserProperties: no
Suspects:       no
Form:           none
JavaScript:     no
Pages:          1601
Encrypted:      no
Page size:      352 x 288 pts
Page rot:       0
File size:      534407296 bytes
Optimized:      no
PDF version:    1.3


  


  with :

  


  $ convert --version
Version: ImageMagick 6.9.10-23 Q16 x86_64 20190101 https://imagemagick.org
Copyright: © 1999-2019 ImageMagick Studio LLC
License: https://imagemagick.org/script/license.php
Features: Cipher DPC Modules OpenMP 
Delegates (built-in): bzlib djvu fftw fontconfig freetype jbig jng jpeg lcms lqr ltdl lzma openexr pangocairo png tiff webp wmf x xml zlib


  


  and

  


  $ file input.mp4 
input.mp4: ISO Media, MP4 Base Media v1 [IS0 14496-12:2003]
$ ffprobe -v quiet -print_format json  -show_streams input.mp4 | grep codec_long_name
            "codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",


  


• checkasm : use perf API on Linux ARM*

  1er septembre 2017, par Clément Bœsch

  checkasm : use perf API on Linux ARM*
  On ARM platforms, accessing the PMU registers requires special user
  
  access permissions. Since there is no other way to get accurate timers,
  
  the current implementation of timers in FFmpeg rely on these registers.
  
  Unfortunately, enabling user access to these registers on Linux is not
  
  trivial, and generally involve compiling a random and unreliable github
  
  kernel module, or patching somehow your kernel.
  Such module is very unlikely to reach the upstream anytime soon. Quoting
  
  Robin Murphin from ARM :
  > Say you do give userspace direct access to the PMU ; now run two or more
  
  > programs at once that believe they can use the counters for their own
  
  > "minimal-overhead" profiling. Have fun interpreting those results...
  
  >
  
  > And that's not even getting into the implications of scheduling across
  
  > different CPUs, CPUidle, etc. where the PMU state is completely beyond
  
  > userspace's control. In general, the plan to provide userspace with
  
  > something which might happen to just about work in a few corner cases,
  
  > but is meaningless, misleading or downright broken in all others, is to
  
  > never do so.
  As a result, the alternative is to use the Performance Monitoring Linux
  
  API which makes use of these registers internally (assuming the PMU of
  
  your ARM board is supported in the kernel, which is definitely not a
  
  given...).
  While the Linux API is obviously cross platform, it does have a
  
  significant overhead which needs to be taken into account. As a result,
  
  that mode is only weakly enabled on ARM platforms exclusively.
  Note on the non flexibility of the implementation : the timers (native
  
  FFmpeg vs Linux API) are selected at compilation time to prevent the
  
  need of function calls, which would result in a negative impact on the
  
  cycle counters.
  

  • [DH] configure
  • [DH] tests/checkasm/checkasm.c
  • [DH] tests/checkasm/checkasm.h

• mpegvideo : Expand macro

  10 juin 2015, par Vittorio Giovara

  mpegvideo : Expand macro
  Having this macro in an header only facilitates the use of such header.
  
  The code increase is minimal and files have one less dependency
  
  on mpegvideo.h.
  

  • [DBH] libavcodec/flvenc.c
  • [DBH] libavcodec/h261enc.c
  • [DBH] libavcodec/mpegvideo.h
  • [DBH] libavcodec/mpegvideo_enc.c
  • [DBH] libavcodec/rv10enc.c
  • [DBH] libavcodec/rv20enc.c