This applescript below will per drag and drop convert mts files to flv using ffmpeg

The scripts can be downloaded here: http://www.auditeon.com/xyz/mts2flv.app.zip. ffmpeg is already stored in the following directory:

mts2flv.app/Contents/Resources/

For alternatives to quicktime, see here: http://www.rkuntz.org/pmwiki.php?n=Code.Mts2Mov

1. Save the applescript, named mts2flv, from below to a directory. In Applescript editor save as Application
2. Copy ffmpeg into the following subdirectory of the applescript directory: mts2flv.app/Contents/Resources/
3. If not, make ffmpeg executable with:
   chmod +x ffmpeg

-- This droplet processes both files or folders of files dropped onto the applet
 
on open (these_items)
	repeat with i from 1 to the count of these_items
		set this_item to (item i of these_items)
		set the item_info to info for this_item
		if folder of the item_info is true then
			process_folder(this_item)
			--		else if (alias of the item_info is false) and (the name extension of the item_info is "mts") then
		else if (alias of the item_info is false) then
			process_item(this_item)
		end if
	end repeat
end open
 
-- this sub-routine processes folders
on process_folder(this_folder)
	set these_items to list folder this_folder without invisibles
	repeat with i from 1 to the count of these_items
		set this_item to alias ((this_folder as text) & (item i of these_items))
		set the item_info to info for this_item
		if folder of the item_info is true then
			process_folder(this_item)
			--		else if (alias of the item_info is false) and (the name extension of the item_info is "pdf") then
		else if (alias of the item_info is false) then
			process_item(this_item)
		end if
	end repeat
end process_folder
 
-- this sub-routine processes files
on process_item(this_item)
	-- NOTE that the variable this_item is a file reference in alias format
	set full_path to the POSIX path of this_item
	try
		set ffmpeg_location to quoted form of POSIX path of (path to resource "ffmpeg") -- ffmpeg binary location
		tell application "Finder"
			set x to path to me
			set y to name of file x as text
		end tell
		-- from http://www.petercarrero.com/content/2009/10/11/converting-mts-avchd-flv-ffmpeg
		display alert "Processing ..." message "Processing file " & this_item giving up after 1
		with timeout of 27000 seconds
			do shell script ffmpeg_location & " -i " & quoted form of full_path & " -vcodec flv -f flv -r 25 -s 800x450 -aspect 16:9 -b:v 2000k -g 160 -cmp 2 -subcmp 2 -mbd 2 -trellis 2 -acodec libmp3lame -ac 2 -ar 44100 -ab 256k " & quoted form of full_path & ".flv"
		end timeout
	on error the error_message number the error_number
		display dialog "Error: " & the error_number & ". " & the error_message
	end try
end process_item
 
 
on getFileName(thefile)
	set {oldDelims, AppleScript's text item delimiters} to {AppleScript's text item delimiters, {":"}}
	set mytextfilename to last text item of (thefile as text)
	set AppleScript's text item delimiters to oldDelims
	return mytextfilename
end getFileName