revert to slow preset, add code for cleaning up transcoded files

ltbtranscodedtobedeleted table in mythconverg has been added:

CREATE TABLE `ltbtranscodedtobedeleted` (
  `basename` varchar(256) NOT NULL,
  `deleted` tinyint(1) NOT NULL DEFAULT '0',
  `expirydate` datetime NOT NULL,
  `updatetimestamp` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8

ffmpeg-myth.scm

@@ -18,7 +18,7 @@
 (define ffmpeg-bin "/usr/bin/ffmpeg")
 (define ffprobe-bin "/usr/bin/ffprobe")
 (define ffprobe-separator #\page) ;; 
-(define ffmpeg-transcoding-options  "-c:v libx264 -preset veryfast -crf 21 -c:a ac3 -g 60 -keyint_min 30")
+(define ffmpeg-transcoding-options  "-c:v libx264 -preset slow -crf 21 -c:a ac3 -g 60 -keyint_min 30")
 (define ffmpeg-transcoded-file-muxer 'mpegts) ;; 'matroska
 (define recordings-directory "/var/lib/mythtv/recordings")
 (define working-directory "/mnt/lvraid5/ffmpeg-cut-list.d")
@@ -446,7 +446,6 @@
 							(regexp-substitute/global #f " ltbrecordedmarkup" s 'pre " RECORDEDMARKUP" 'post) 'pre " LTBRECORDEDMARKUP" 'post))))))
     (mythconverg-update-recordedmarkup-table rec sanitize+continue)))
 
-
 (define* (mythconverg-update-recorded-table rec tr-rec #:optional (mv? #t))
   (let* ((chanid (recording-chanid rec))
 	 (starttime (recording-starttime rec))
@@ -459,6 +458,49 @@
     (if mv? (shell-command-to-string (simple-format #f "touch --reference='~a' '~a' && mv '~a' '~a'" input-file input-tr-file input-tr-file recordings-directory)))
     (mysql-commit (simple-format #f "update recorded set cutlist=0, commflagged=0, bookmark=0, transcoded=1, filesize=~a, basename=\"~a\" where chanid=~a and starttime=~a;" tr-filesize tr-basename chanid starttime))))
 
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;;;                       MYTH-CLEAN-RECORDINGS
+;;;; - on successful transcode, FFMPEG-MYTH0 calls MYTHCONVERG-UPDATE-LTBTRANSCODEDTOBEDELETED
+;;;;  which adds an entry in the sql table ltbtranscodedtobedeleted for the file that was transcoded.
+;;;; - MYTH-CLEAN-RECORDING-DIRECTORY queries ltbtranscodedtobedeleted for the list of files with an
+;;;;   expiry date before now+n days; it executes SHELL-CMD on that list; if there are no expired files
+;;;;   it returns an empty list, otherwise the list of files
+;;;; - MYTHCONVERG-UPDATE-DELETED-LTBTRANSCODEDTOBEDELETED takes the list of files from 
+;;;;   MYTH-CLEAN-RECORDING-DIRECTORY and sets the deleted flag on each one in the the ltbtranscodedtobedeleted
+;;;;   table.
+;;;;
+;;;;   Debug/test: shell-cmd <- echo ; continuation <- (lambda(x) x)
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+(define* (mythconverg-update-ltbtranscodedtobedeleted rec #:optional (continuation mysql-continue))
+  (let* ((basename (if (recording? rec) (recording-basename rec) rec)))
+    (continuation (simple-format #f "insert into ltbtranscodedtobedeleted (basename,deleted,expirydate) values ('~a',0,NOW() + interval 14 day);" basename))))
+(define* (myth-clean-recording-directory #:optional (expiration-date 1) (shell-cmd "rm -f"))
+  (let* ((safe-cdr (lambda (x) (if (null? x) x (cdr x))))
+	 (expired-recordings (map car (safe-cdr (mythconverg-execute+parse (simple-format #f "select basename from ltbtranscodedtobedeleted where deleted=0 and expirydate <= NOW() + interval ~a day;" expiration-date))))))
+    (cond ((null? expired-recordings)
+	   (simple-format #t "myth-clean-recording-directory: no transcoded recordings to remove. Done.\n")
+	   '())
+	  (#t
+	   (simple-format #t "myth-clean-recording-directory: removing transcoded files\n~a\n" (string-join expired-recordings ","))
+	   (let ((cmd (simple-format #f "~a ~a" shell-cmd (string-join (map (lambda(s) (string-concatenate (list recordings-directory s))) expired-recordings) " "))))
+	     (catch 'error-in-shell-command-to-string
+	       ;; thunk - return expired-recordings list
+	       (lambda ()
+		 (shell-command-to-string cmd)
+		 expired-recordings)
+	       ;; handler - return empty list in case of error
+	       (lambda (key cmd str)
+		 '())))))))
+(define* (mythconverg-update-deleted-ltbtranscodedtobedeleted bnl #:optional (continuation mythconverg-execute))
+  (let ((sql-cmds (map (lambda(f) (simple-format #f "update ltbtranscodedtobedeleted set deleted=1 where basename='~a';" f)) bnl)))
+    (unless (null? bnl)
+      (mysql-start-transaction (string-join sql-cmds "\n"))
+      (mysql-commit "")
+      (continuation mysql-cmd))))
+(define* (myth-clean-recordings-update-deleted-ltbtranscodedtobedeleted #:optional (expiration-date 1) (shell-cmd "rm -f") (continuation mythconverg-execute))
+  (mythconverg-update-deleted-ltbtranscodedtobedeleted
+   (myth-clean-recording-directory expiration-date shell-cmd) continuation))
+
 (define (myth-merge-two-recordings chanid starttime)
   (let* ((rec1+2 (mythconverg-execute+parse (simple-format #f "select basename,title from recorded where chanid=~a and starttime >= ~a order by starttime limit 2;" chanid starttime)))
 	 (bn1 (caadr rec1+2))
@@ -542,6 +584,7 @@
 		(mysql-start-transaction "")
 		(mythconverg-update-recorded-seek-table tr-rec)
 		(mythconverg-update-recordedmarkup-table tr-rec)
+		(mythconverg-update-ltbtranscodedtobedeleted rec)
 		;; mysql-commit in this step
 		(mythconverg-update-recorded-table rec tr-rec)
 		(mythconverg-execute mysql-cmd)