Scripting Quicktime export settings

I’m building a Quicktime player script that exports a movie as an image sequence with images captured at specified intervals, i.e., 3 seconds, 5 seconds, etc.

Regarding settings, all of the info I’ve read so far indicates you have to either use default settings or recent settings. I want to distribute this to our creative department and I don’t want them to even have a settings file. I’d like to call it on the fly like this:

 export front document to (exportFolder & exportPrefix) as image sequence using settings "jpg, .25 fps"

except that doesn’t work. It should save a frame every 4 seconds but it doesn’t seem to do anything.

Here is the portion of the script that exports:

if (can export front document as image sequence) then
try
export front document to (exportFolder & exportPrefix) as image sequence using most recent settings
on error errorMsg number errorNum
display dialog "Error (" & errorNum & "):" & return & return & errorMsg buttons "OK" default button 1 with icon caution
end try
 else
 display dialog "QuickTime Player can't export "" & (thisFile as Unicode text) & "" as an image squence." buttons "OK" default button 1 with icon caution
end if

I would like to have the settings embedded in the AS app. Is there a way to do this so I don’t have to distribute a settings file with the app?

The entire script is posted below:


on run
   choose file with prompt "Export these video files to image squences:" with multiple selections allowed without invisibles
   open result
end run

on open droppedItems
   tell application "QuickTime Player"
       activate
       close every window
   end tell
   
   set ASTID to AppleScript's text item delimiters
   repeat with thisItem in droppedItems
       set AppleScript's text item delimiters to {"."}
       get name of (info for thisItem without size)
       try
           set exportPrefix to (text items 1 thru -2 of result) as text
       on error
           set exportPrefix to result
       end try
       set AppleScript's text item delimiters to {""}
       
       tell application "Finder"
           try
               make new folder at (container of thisItem) with properties {name:(exportPrefix & " Image Squence")}
               set exportFolder to result as Unicode text
           on error errorMsg number errorNum
               display dialog "Error (" & errorNum & "):" & return & return & errorMsg buttons "Cancel" default button 1 with icon caution
           end try
       end tell
       
       tell application "QuickTime Player"
           open thisItem
           
           if (can export front document as image sequence) then
               try
                   export front document to (exportFolder & exportPrefix) as image sequence using settings "jpg, .25 fps" --most recent settings
               on error errorMsg number errorNum
                   display dialog "Error (" & errorNum & "):" & return & return & errorMsg buttons "OK" default button 1 with icon caution
               end try
           else
               display dialog "QuickTime Player can't export "" & (thisFile as Unicode text) & "" as an image squence." buttons "OK" default button 1 with icon caution
           end if
           
           close front document
       end tell
   end repeat
   
   set AppleScript's text item delimiters to ASTID
   quit application "QuickTime Player"
end open