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• avformat/segafilmenc : Don't store packet info in linked list

  17 juillet 2020, par Andreas Rheinhardt

  avformat/segafilmenc : Don't store packet info in linked list
  Up until now, the Sega FILM muxer would store some information about
  
  each packet in a linked list. When writing the trailer, the information
  
  in said linked list would be used to write a table in the file header.
  
  Each entry in said table is 16 bytes long, but each entry of the linked
  
  list is 32 bytes long (assuming 64 bit pointer and no padding).
  
  Therefore it makes sense to remove the linked list and write the array
  
  entries directly into a dynamic buffer while writing the packet (this is
  
  possible because the table entries don't depend on any information not
  
  available when writing the packet (the offset is not relative to the
  
  beginning of the file, but to the end of the table). This also
  
  simplifies writing the array at the end (there is no need to traverse a
  
  linked list).
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/segafilmenc.c

• Better way to use ffmpeg with vidstab and encoding 2 pass

  17 juin 2020, par Guillaume B.

  I scan old 8mm films 
so I have folder with set of jpeg

  



  I transform them to films using ffmpeg ( I choose x264 2 pass encoding)

  



  //On all folder that start by 1 I launch the pass1 for x264

for f in 1*/ ; do cd "$f"; ffmpeg -y -r 18 -i img%05d.jpg -c:v libx264 -s 1200x898 -b:v 3000k -pass 1 -an -f mp4 /dev/null; cd ..; done

//On all folder that start by 1 I launch the pass2 x264

for f in 1*/ ; do cd "$f"; ffmpeg -y -r 18 -i img%05d.jpg -c:v libx264 -s 1200x898 -b:v 3000k -pass 2 ../"`echo ${PWD##*/}`.mp4"; cd ..; done


  



  —> Before I have set of folder with jpeg

  



  


  1965-FamilyStuff01\img1111.jpg,..,img9999.jpg

  
 


  1965-FamilyStuff02\img1111.jpg,..,img9999.jpg

  


  



  and I get

  



  


  1965-FamilyStuff01.mp4

  
 


  1965-FamilyStuff02.mp4

  


  



  then I discover vidstab that also need 2 pass

  



  // Stabilize every Video of a folder

  



  mkdir stab;for f in ./*.mp4 ; do echo "Stabilize $f" ; 
ffmpeg -i "$f" -vf vidstabdetect=shakiness=5:accuracy=15:stepsize=6:mincontrast=0.3:show=2 -y -f mp4 /dev/null; 
ffmpeg -i "$f" -vf vidstabtransform=smoothing=30:input="transforms.trf":interpol=linear:crop=black:zoom=0:optzoom=1,unsharp=5:5:0.8:3:3:0.4 -y "stab/$f" 
; done; rm transforms.trf;


  



  But I ask myself, that perhaps the order is not correct or perhaps there is a way to do the encoding with vidstab in less than 4 pass (2 pass for x264 encoding then 2 pass for vidstab)
or perhaps the order should be change to optimize quality of film output)

  


• Better way to use ffmpeg with vidstab and encoding 2 pass

  17 juin 2020, par Guillaume B.

  I scan old 8mm films
so I have folder with set of jpeg

  


  I transform them to films using ffmpeg ( I choose x264 2 pass encoding)

  


  //On all folder that start by 1 I launch the pass1 for x264

for f in 1*/ ; do cd "$f"; ffmpeg -y -r 18 -i img%05d.jpg -c:v libx264 -s 1200x898 -b:v 3000k -pass 1 -an -f mp4 /dev/null; cd ..; done

//On all folder that start by 1 I launch the pass2 x264

for f in 1*/ ; do cd "$f"; ffmpeg -y -r 18 -i img%05d.jpg -c:v libx264 -s 1200x898 -b:v 3000k -pass 2 ../"`echo ${PWD##*/}`.mp4"; cd ..; done


  


  —> Before I have set of folder with jpeg

  


  


  1965-FamilyStuff01\img1111.jpg,..,img9999.jpg

  


  1965-FamilyStuff02\img1111.jpg,..,img9999.jpg

  


  


  and I get

  


  


  1965-FamilyStuff01.mp4

  


  1965-FamilyStuff02.mp4

  


  


  then I discover vidstab that also need 2 pass

  


  // Stabilize every Video of a folder

  


  mkdir stab;for f in ./*.mp4 ; do echo "Stabilize $f" ; 
ffmpeg -i "$f" -vf vidstabdetect=shakiness=5:accuracy=15:stepsize=6:mincontrast=0.3:show=2 -y -f mp4 /dev/null; 
ffmpeg -i "$f" -vf vidstabtransform=smoothing=30:input="transforms.trf":interpol=linear:crop=black:zoom=0:optzoom=1,unsharp=5:5:0.8:3:3:0.4 -y "stab/$f" 
; done; rm transforms.trf;


  


  But I ask myself, that perhaps the order is not correct or perhaps there is a way to do the encoding with vidstab in less than 4 pass (2 pass for x264 encoding then 2 pass for vidstab)
or perhaps the order should be change to optimize quality of film output)