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• bash : correct syntax to get framerate and add to ffmpeg command [duplicate]

  2 mars 2023, par daedalus

  I have a bash script to do AI video upscaling but I am having problems getting the framerate in the source file and then using it in the ffmpeg command for the encode of the upscaled frames. I'm a bash newb so not sure what syntax i'm using is wrong.

  


  #!/bin/sh
PS4='$LINENO: '
set -x
for arg
do
    mkdir "${arg%.*}"
    mkdir "${arg%.*}US"
    cd "${arg%.*}"
    fps = $(/usr/bin/mediainfo "$arg" "--inform=Video;%FrameRate%")
    nice -19 /bin/ffmpeg -i "$arg" -qscale:v 1 -qmin 1 -qmax 1 -vsync passthrough frame%04d.jpg
    cd ..
    /Programs/realesrgan-ncnn-vulkan -i "${arg%.*}" -o "${arg%.*}US" -n realesrgan-x4plus -s 4 -f jpg
    cd "${arg%.*}US"
    nice -19 /bin/ffmpeg -framerate $fps -i frame%04d.jpg -pix_fmt yuv420p -c:v libx265 -crf 20 "${arg%.*}US.mkv" 
    rm -rf "${arg%.*}"
    rm -rf "${arg%.*}US"
done


  


  when I debug it looks like it gets the frame rate but then say command not found for some reason, when the ffmpeg command is used the frame rate is missing even tho I specify the $fps variable .

  


  99: /usr/bin/mediainfo '/media/M2/vid.mkv' '--inform=Video;%FrameRate%'
9: fps = 30.000
/scripts/batchVideoUpscale: line 9: fps: command not found


  


  and at the end>

  


  nice -19 /bin/ffmpeg -framerate -i frame%04d.jpg -pix_fmt yuv420p -c:v libx265 -crf 20 vidUS.mkv


  


  note that the frame rate of 30.00 is missing even tho I include $fps in bash script after -framerate.

  


• ffmpeg producing strange NAL suffixes for MPEG-TS with h264

  13 décembre 2016, par ElDorado

  I am making h264 stream analyzer and have found strange ffmpeg behaviour while writing and reading same frame packetized with MPEG-TS.

  I have dumped both encoding and decoding frame data in HEX and found these differences :

  At the beginning of frame there is NAL delimiter added :

  + 00
  
  + 00
  
  + 00
  
  + 01
  
  + 09
  
  + f0

  that looks absolutely legit to me.

  But here comes strange things :

  If current packet is not the last one than some suffix is added (i.e. there is no this suffix in the last written frame). And this suffix is added to current read frame (i.e. this is not prefix to next frame).

  + e0
  
  + 00
  
  + 00
  
  + 00
  
  + 01
  
  + ce
  
  + 8c
  
  + 4d
  
  + 9d
  
  + 10
  
  + 8e
  
  + 25
  
  + e9
  
  + fe

  (exactly starting with e0 byte added)

  I am trying to understand what that could mean. If 00000001 is NAL header than it is followed by ce byte with forbidden zero-bit equals 1 that is absolutely broken.

  I am using fork from ffmpeg github repo last merged with 89092fafdde894c6ba4d4f8e3cd1cce0d68bfc22 commit.

  ffmpeg is built with --disable-everything --enable-encoder=libopenh264 --enable-muxer=mpegts --enable-demuxer=mpegts --enable-protocol=file --enable-parser=h264 --enable-decoder=libopenh264 --enable-shared --disable-static --disable-programs --disable-doc --enable-libopenh264 options

• Muxing multiple JPEG into a JXL animation

  11 août 2023, par malat

  Using ffmpeg I can mux multiple JPEG into a M-JPEG container without any loss since it is a just a plain bitstream copy :

  


  ffmpeg -framerate 30 -i input%03d.jpg -codec copy output.mjpeg


  


  Recently linux distributions started to offer JPEG-XL command line tools. I can now recode (lossless recompression) of JPEG into JXL :

  


  % file input.jpg
input.jpg: JPEG image data, JFIF standard 1.01, aspect ratio, density 1x1, segment length 16, baseline, precision 8, 1016x708, components 3
% cjxl input.jpg output.jxl
% djxl output.jxl output.jpg
% md5sum input.jpg output.jpg
bea9e9c74e3580f6196ba9ac21509652  input.jpg
bea9e9c74e3580f6196ba9ac21509652  output.jpg


  


  However I fail to understand how to create a JXL animation (more than one JPEG) ?

  


  Eg :

  


  % ffmpeg -framerate 30 -i input%03d.jpg -codec copy output.jxl
[...]
[image2 @ 0x55c22e680040] The specified filename 'output.jxl' does not contain an image sequence pattern or a pattern is invalid.
[image2 @ 0x55c22e680040] Use a pattern such as %03d for an image sequence or use the -update option (with -frames:v 1 if needed) to write a single image.
[image2 @ 0x55c22e680040] Cannot write more than one file with the same name. Are you missing the -update option or a sequence pattern?
av_interleaved_write_frame(): Invalid argument
frame=    2 fps=0.0 q=-1.0 Lsize=N/A time=00:00:00.06 bitrate=N/A speed= 223x
video:224kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Conversion failed!


  


  Or :

  


  % cjxl input*.jpg output.jxl
Unknown argument: input002.jpg
Use 'cjxl -h' for more information