#!/bin/sh
##
## Nautilus
## SCRIPT: 30d_1mkvCapFile_CONVERTto_FLV-VP6F-MP3_ffmpeg2pass_PRELIM.sh
##
## PURPOSE: Using 'ffmpeg', this script converts an input movie file
##          to a '.flv' container movie file.
##
##          This script is intended to use as input '.mkv' (Matroska container)
##          movie files that are 'lossless' H264-and-PCM
##          screen-and-audio-captures from a 'XscreenANDpulseAUDIO_CAPTURE'
##          script --- but it may work with other movie file inputs, that is,
##          different container formats, such as '.flv' or '.avi' or '.mpg'.
##
##          The input video stream (possibly near LOSS-LESS) is converted to
##          a *LOSSY* VP6F video stream and the input audio stream (possibly
##          near LOSS-LESS) is converted to a *LOSSY* MP3 audio stream.
##
## METHOD: Uses 'zenity --info' to show info on how this utility works.
##
##         Uses 'zenity --entry' to prompt for an image size (x,y-pixels)
##         for the output movie file.
##
##         Runs 'ffmpeg' in two passes --- once with '-f flv -an -vcodec vp6f'
##         parms (no audio) --- and once with '-f flv' and '-vcodec vp6f' and
##         '-acodec libmp3lame' parms.
##
##         Runs 'ffmpeg' in an 'xterm' so that messages can be seen.
##
##         When the conversion is done, this script
##         shows the '.flv' file in a movie player.
##
##     REFERENCES: http://ubuntuforums.org/archive/index.php/t-1392026.html
##                 "HOWTO: Proper Screencasting on Linux" by verb3k
##                 Also web search on terms like 'ffmpeg flv vp6'.
##
## HOW TO USE: In Nautilus, select a (.mkv) movie file.
##             Then right-click and choose this script to run (name above).
##
##############################################################################
## Started: 2011may17
## Changed: 2011dec11 Removed '--no-wrap' from the 'zenity --entry' prompt for
##                    image size. '--no-wrap' is not implemented for '--entry'.
## Changed: 2012may24 Changed script name in comments above and touched up
##                    the comments. Changed some indenting below.
###########################################################################

## FOR TESTING: (display statements that execute)
# set -x

###########################################
## Get the INPUT movie filename.
########################################################################
## We can create a LOSSLESS H264-PCM-MKV file from the script
## '30a_VIDpulseAUD_screenCAPTURElossless_toH264-PCM-MKV_ffmpeg_Qquit.sh'
## (according to 'verb3k')
#######################################################################

FILENAME="$1"


######################################
## Prepare the OUTPUT '.flv' filename.
## (The suffix determines the container
## type that 'ffmpeg' creates.)
######################################

FILEOUT="/tmp/${USER}_MOVIEfileCONVERTEDto_LOSSY-vp6f-mp3.flv"

if test -f "$FILEOUT"
then
   rm -f "$FILEOUT"
fi


##########################################
## Show info on how this utility works.
##########################################

CURDIR="`pwd`"
CURDIRFOLDED=`echo "$CURDIR" | fold -55`

SCRIPT_BASENAME=`basename $0`

zenity --info \
   --title "INFO on this CONVERT-a-VIDEO utility." \
   --no-wrap \
   --text "\
This utility, $SCRIPT_BASENAME ,
will use 'ffmpeg' to (try to) convert the INPUT file

  $FILENAME

in directory

  $CURDIRFOLDED

into lossy VP6F video and lossy MP3 audio in an FLV container
in OUTPUT file

  $FILEOUT

'ffmpeg' will be started (twice) in a terminal window so that startup
and encoding messages can be watched. When the 2nd-stage 'ffmpeg' is
done (that is, when coding messages stop), CLOSE the terminal window.

  The output file, if good, will be shown in a video player.

Now, CLOSE this window to get a PROMPT for image size of the
output --- and to, after that, START the 1st of 2 ffmeg-windows."


############################################################
## Ask for the image SIZE for the NEW LOSSY file that we
## are about to make from the INPUT video file.
############################################################

NEWSIZE=""

NEWSIZE=$(zenity --entry \
   --title "ENTER image SIZE for the new VP8-VORBIS-WEBM file to be made." \
   --text "\
Enter an image size for the WEBM file
$FILEOUT
that will now be made from the INPUT file
$FILENAME
Examples:
  320x240  = QVGA  (4:3 = 1.33...)
  352x288  = CIF   (1.22...)
  640x480  = VGA   (4:3 = 1.33...)
  720x480  = NTSC screen size (1.5)
  720x576  = PAL screen size (1.25)
  800x600  = SVGA  (4:3 = 1.33...)
 1024x768  = XGA   (4:3 = 1.33...)
 1280x720  = HD720 (16:9 = 1.77...)
 1280x1024 = SXGA  (5:4 = 1.25)
 1920x1080 = HD1080 (16:9 = 1.77...)
 1600x1200 = UXGA  (4:3 = 1.33...)
        0  = same size as input file

'ffmpeg' CONVERSION will be started in a terminal window (twice)
so that startup and coding messages can be watched.

When the 2nd 'ffmpeg' run is done, CLOSE the terminal window.
  The output file, if good, will be shown in a video player." \
   --entry-text "640x480")

if test "$NEWSIZE" = ""
then
   exit
fi

if test "$NEWSIZE" = "0"
then
   SPARM=""
else
   SPARM="-s $NEWSIZE"
fi

###########################################################
## Convert the input movie file into a lossy VP6F video
## stream and lossy MP3 audio stream in an FLV container.
## NOTE: This is a two-step process - 2 invocations of 'ffmpeg'.
###################################################################
## The basic format for these 2 'ffmpeg' commands came
## FROM "HOWTO: Proper Screencasting on Linux" by verb3k,
## web URL above.
###################################################################
## We do each ffmpeg pass in a terminal window to watch progress,
## via messages from 'ffmpeg'.
###########################################################


## Pass 1: (Change the bitrate '-b 750k' to control the size/quality
##          tradeoff.)

xterm -bg black -fg white -hold -geometry 90x48+100+100 -e \
   ffmpeg -i "$FILENAME" -f flv -an -vcodec vp6f $SPARM \
   -b 750k -pass 1 "$FILEOUT"


## Pass 2: (Could use '-threads 2', say, if your computer has 4 processors
##          and you want to leave 2 processors available for other tasks.
##          '-threads 0' is supposed to try to use all the processors.
##          If your CPU is not multi-threaded, you can omit the '-threads'
##          option completely.)

xterm -bg black -fg white -hold -geometry 90x48+150+150 -e \
   ffmpeg -i "$FILENAME" -f flv \
         -vcodec vp6f $SPARM -b 750k \
         -acodec libmp3lame -ab 128k -ar 22050 -ac 1 \
         -threads 0 -pass 2 "$FILEOUT"

## To minimize the size of the audio data we may use parms like
##    '-ab 96k  -ar 22050 -ac 1'   OR   '-ab 64k  -ar 22050 -ac 1'
## instead of parms like
##    '-ab 128k -ar 44100 -ac 2'

## FROM http://forum.php.pl/lofiversion/index.php/t156193.html
##
## "If you need high quality .flv video - don't use old H.263 flv codec (flash 7)
## - use VP6 (flash 8) or H.264 (flash 9) instead.
## They are almost same quality (vp6 less blocky, h264 more details)
## Also use two-pass encoding - one-pass loose quality or takes much more
## space for same quality compared to two-pass."
##
## Examples (working?) from that forum:
##
## ffmpeg -y -i /test.m4v -s 640x480 -vcodec vp6f -f flv -b 200K -r 25 /test.flv
##
## ffmpeg -y -i /test.mov -s 640x480 -deinterlace -ab 32 -r 15 -ar 22050 -ac 1
##        -vcodec flv -b 1024K -r 24 -f flv /test.flv

#####################################################################
## Basic ffmpeg syntax is:
##  ffmpeg [input options] -i [input file] [output options] [output file]
##
## Note that 'ffmpeg' determines the container format of the output file
## based on the extension you specify. For example, if you specify the
## extension as '.mkv', your file will be muxed into an Matroska container.
##
## Meaning of the 'popular' ffmpeg parms:
##
## -i  val = input filename
##
## -acode codec - to force the audio codec. Example: -acodec libmp3lame
## -ab val = audio bitrate in bits/sec (default = 64k)
## -ar val = audio sampling frequency in Hz (default = 44100 Hz)
## -ac channels - default = 1
##
## -vcodec codec - to force the video codec. Example: -vcodec mpeg4 
##                 Try  "ffmpeg -formats"
## -r  val = frame rate in frames/sec
## -b  val = video bitrate in kbits/sec (default = 200 kbps)
## -s  val = frame size, wxh where w and h are pixels or abbrevs:
##          qqvga =  160x120
##           qvga =  320x240
##            cif =  352x288
##            vga =  640x480
##           svga =  800x600
##            xga = 1024x768
##           sxga = 1280x1024
##           uxga = 1600x1200
##               
## Some other useful params:
##
## Audio:
##   -an = disable audio recording
## 
## Video:
##   -vn = disable video recording
##   -y  = overwrite output file(s)
##   -aspect (4:3, 16:9 or 1.3333, 1.7777)
##   -croptop pixels
##   -cropbottom pixels
##   -cropleft pixels
##   -cropright pixels
##   -padtop (bottom, left, right)
##   -padcolor <6 digit hex number>
##   -ss position = seek to given position, in secs or hh:mm:ss[.xxx]
##   -t duration - format is hh:mm:ss[.xxx]
##   -fs file-size-limit
##   -target type - where type is vcd or svcd or dvd or ..., then
##                  bitrate, codecs, buffersizes are set automatically.
##   -pass n, where n is 1 or 2
##
## Other:
##   -debug
##   -threads count
#######################################################################


##############################
## Show the OUTPUT movie file.
##############################

if test ! -f "$FILEOUT"
then
   exit
fi

# MOVIEPLAYER="/usr/bin/vlc"
# MOVIEPLAYER="/usr/bin/mplayer"
# MOVIEPLAYER="/usr/bin/gmplayer -vo xv"
# MOVIEPLAYER="/usr/bin/smplayer"
# MOVIEPLAYER="/usr/bin/totem"

MOVIEPLAYER="/usr/bin/ffplay -stats"

xterm -fg white -bg black -hold -geometry 90x32+100+100 \
      -e $MOVIEPLAYER "$FILEOUT"

## NOTE: 'totem' (based on gstreamer, version ?) tends to play
##        only a second or so of an mpeg1video that I created
##        with ffmpeg.
##        But 'ffplay' does a good job. 'mplayer' does OK.
##        'totem' is suspect. (Or the ffmpeg recording parms?)


#########################################################
## Use a user-specified MOVIEPLAYER.  Someday?
#########################################################

# . $HOME/.freedomenv/feNautilusScripts/set_DIR_NautilusScripts.shi
# . $DIR_NautilusScripts/.set_VIEWERvars.shi

# $MOVIEPLAYER "$FILEOUT" &