Fix thumbnail generation

webif/lib/ts.class

@@ -354,13 +354,14 @@ ts method mkbmps {{offset 0}} {
 
 ts method mkbmp {{offset 0} {ext ""}} {
 	set bfile [file rootname $file]
+    set bmpfile "$bfile$ext.bmp"
     set cmd [list /mod/bin/ffmpeg -loglevel fatal -ss $offset -i $file \
-	    -frames 1 -pix_fmt argb -vf vflip -s 140x78 "$bfile$ext.bmp"]
-	if {[catch { exec {*}$cmd } msg]} {
-		puts "ERROR: $msg"
-		return 0
+        -frames 1 -pix_fmt argb -vf vflip -s 140x78 -y $bmpfile]
+    catch { exec {*}$cmd }
+    if {![catch { file stat $bmpfile stbmp }]} {
+            if {[dict get $stbmp size] != 0} { return 1 }
     }
-	return 1
+    return 0
 }
 
 ts method mkthm {{offset 0}} {