WIP

helpers/_error.function.fish

+function _error --description 'Call with `_error <msg> <var1> <var2> … <var_n>` to abort the program' --no-scope-shadowing
+  for i in $argv[2..]
+    set out $out {$i}={$$i}
+  end
+
+  echo $argv[1] '('(string join ', ' $out)')'
+  exit 1
+end

helpers/_fish_gen_cleanup_fn.function.fish

+function _fish_gen_cleanup_fn --argument name body
+  if [ (count $argv) -ne 2 ] || [ -z "$argv[1]" ] || [ -z "$argv[2]" ]
+    echo Invalid params '(expected 2, name and body, both non-empty)'
+    return 1
+  end
+
+  set current_filename (status filename)
+  if [ "$current_filename" = "Standard input" ]
+    set -e current_filename
+  else
+    set current_filename (systemd-escape --path (basename $current_filename))
+
+  set name _cleanup_"$(string escape --style=var {$current_filename}_ | string collect
+      )"(string escape --style=var $name)_(uuidgen)
+# need \; and \<newline> for line break escaping and command delimiting
+  echo                                                                                          \
+  function $name --on-event fish_exit                                                         \;\
+    $body                                                                                     \;\
+    functions --erase $name                                                                   \;\
+  end | source
+end

vmaf.fish

+#!/usr/bin/env fish
+
+
+set FZF_PROMPT              'Select original file> '
+set FZF_STARTING_QUERY      'orig'
+set FFMPEG_ARGS (string trim '
+    -i $vid -i $ORIG -filter_complex \
+        "[0:v]setpts=PTS-STARTPTS[distorted]; \
+         [1:v]setpts=PTS-STARTPTS[ref]; \
+         [distorted][ref]libvmaf=feature='name=psnr':n_threads=8:log_fmt=json"
+' | string collect)
+
+
+. (dirname (status --current-filename))/helpers/_error.function.fish
+
+switch (count $argv)
+case 1
+  set ORIG $argv
+case \*
+  _error 'need original video' argv[3..]
+end
+
+set ORIG (realpath (fzf --prompt $FZF_PROMPT --query $FZF_STARTING_QUERY))
+set -q MAXDEPTH || set MAXDEPTH 1
+
+set VIDEO_VILES (find . -maxdepth $MAXDEPTH -type f | filter_by_video | string match )
+
+for vid in (find . -maxdepth $MAXDEPTH -type f | filter_by_video)
+  set vid (realpath $vid)
+  [ -r "$vid" ] || _error "sanity check failed: video '$vid' not readable" ORIG PWD MAXDEPTH
+
+  set output_file {$vid}_vmaf.txt
+  echo touch $output_file
+  #TODO comment in [ -w "$output_file" ] || _error "cannot write to '$output_file'" vid
+
+  set args_tmp (mktemp --suffix .fish); function ___cleanup_args_tmp --on-event fish_exit; rm -rf $args_tmp; end
+  echo $FFMPEG_ARGS >$args_tmp
+  nano $args_tmp
+  [ ! -s $args_tmp ] && _error 
+
+  echo $ffmpeg_args
+
+end