MTD

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Revision as of 01:17, 14 March 2008 by Karlg100 (talk | contribs) (Forwarding MythFrontend to a remote MTD)

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MTD ( Myth Transcoding Daemon ) is part of the MythDVD plugin.

Transcoding ("ripping") a DVD requires you to run the Myth Transcoding Daemon (mtd). To ensure that mtd is configured correctly, you should first test it at the command line.

 $ mtd -n


The last line of text should show something like:

 mtd is listening on port 2342

This indicates that mtd is ready for use. Once you've successfully tested mtd in the foreground, type CTRL-C to stop mtd. You may then start it as a background (daemon) process.

 $ mtd -d

transcode

If you are converting a DVD at the "good" setting, you are converting from mpeg2, to mpeg4 (xvid) internally mtd uses the transcode program.

# transcode -h
transcode v1.0.2 (C) 2001-2003 Thomas Oestreich, 2003-2004 T. Bitterberg

Usage: transcode [options]

options:
 -i name             input file/directory/device/mountpoint/host name
 -H n                auto-probe n MB of source (0=off) [1]
 -p file             read audio stream from separate file [off]
 -x vmod[,amod]      video[,audio] import modules [null]
 -a a[,v]            extract audio[,video] track [0,0]
--dvd_access_delay N delay DVD access by N seconds [3]

 -e r[,b[,c]]        PCM audio stream parameter [48000,16,2]
 -E r[,b[,c]]        audio output samplerate, bits, channels [as input]
 -n 0xnn             import audio format id [0x2000]
 -N 0xnn             export audio format id [0x55]
 -b b[,v[,q[,m]]]    audio encoder bitrate kBits/s[,vbr[,quality[,mode]]] [128,0,5,0]
--no_audio_adjust    disable audio frame sample adjustment [off]
--no_bitreservoir    disable lame bitreservoir [off]
--lame_preset name[,fast]  use lame preset with name. [off]

 -g wxh              RGB video stream frame size [720x576]
--import_asr C       set import display aspect ratio code C [auto]
--export_asr C       set export display aspect ratio code C [as input]
--export_par N,D     set export pixel aspect ratio [auto]
--keep_asr           try to keep aspect ratio (only with -Z) [off]
 -f rate[,frc]       input video frame rate[,frc] [25.000,0] fps
--export_fps f[,c]   output video frame rate[,code] [as input] [25.000,3]
--export_frc F       set export frame rate code F [as input]
--hard_fps           disable smooth dropping (for variable fps clips) [off]

 -o file             output file name
 -m file             write audio stream to separate file [off]
 -y vmod[,amod]      video[,audio] export modules [null]
 -F codec            encoder parameter strings [module dependent]
 --avi_limit N       split output AVI file after N MB [2048]
 --avi_comments F    Read AVI header comments from file F (see transcode(1)) [off]

 -d                  swap bytes in audio stream [off]
 -s g[,c[,f[,r]]]    increase volume by gain,[center,front,rear] [off,1,1,1]

 -u m[,n]            use m framebuffer[,n threads] for AV processing [10,1]
 -A                  use AC3 as internal audio codec [off]
 -V                  use YV12/I420/YUV420 as internal video format [deprecated, default]
 --use_rgb           use RGB as internal video format [off]
--uyvy               use UYVY/YUV422 as internal video format [off]
 -J f1[,f2[,...]]    apply external filter plugins [off]
 -P flag             pass-through flag (0=off|1=V|2=A|3=A+V) [0]

 -D num              sync video start with audio frame num [0]
--av_fine_ms t       AV fine-tuning shift t in millisecs [autodetect]

 -M mode             demuxer PES AV sync mode (0=off|1=PTS only|2=full) [1]
 -O                  flush lame mp3 buffer on encoder stop [off]

 -r n[,m]            reduce video height/width by n[,m] [off]
 -B n[,m[,M]]        resize to height-n*M rows [,width-m*M] columns [off,32]
 -X n[,m[,M]]        resize to height+n*M rows [,width+m*M] columns [off,32]
 -Z wxh[,fast]       resize to w columns, h rows with filtering [off,notfast]
--zoom_filter str    use filter string for video resampling -Z [Lanczos3]

 -C mode             enable anti-aliasing mode (1-3) [off]
--antialias_para w,b center pixel weight, xy-bias [0.333,0.500]

 -I mode             enable de-interlacing mode (1-5) [off]

 -K                  enable b/w mode [off]
 -G val              gamma correction (0.0-10.0) [off]
 -z                  flip video frame upside down [off]
 -l                  mirror video frame [off]
 -k                  swap red/blue (Cb/Cr) in video frame [off]

 -j t[,l[,b[,r]]]    select frame region by clipping border [off]
 -Y t[,l[,b[,r]]]    select (encoder) frame region by clipping border [off]
--pre_clip t[,l[,b[,r]]]  select initial frame region by clipping border [off]
--post_clip t[,l[,b[,r]]] select final frame region by clipping border [off]

 -w b[,k[,c]]        encoder bitrate[,keyframes[,crispness]] [1800,250,100]
--video_max_bitrate  maximum bitrate when encoding variable bitrate MPEG-2 streams [same as -w]
 -R n[,f1[,f2]]      enable multi-pass encoding (0-3) [0,divx4.log,pcm.log]
 -Q n[,m]            encoding[,decoding] quality (0=fastest-5=best) [5,5]
--divx_quant min,max divx encoder min/max quantizer [2,31]
--divx_rc p,rp,rr    divx encoder rate control parameter [2000,10,20]
--divx_vbv_prof N    divx5 encoder VBV profile (0=free-5=hiqhq) [3]
--divx_vbv br,sz,oc  divx5 encoder VBV params (bitrate,size,occup.) [10000,192,36864]

 -c f1-f2[,f3-f4]    encode only f1-f2[,f3-f4] (frames or HH:MM:SS) [all]
 -t n,base           split output to base%03d.avi with n frames [off]
--dir_mode base      process directory contents to base-%03d.avi [off]
--frame_interval N   select only every Nth frame to be exported [1]

 -U base             process DVD in chapter mode to base-ch%02d.avi [off]
 -T t[,c[-d][,a]]    select DVD title[,chapter(s)[,angle]] [1,1,1]

 -W n,m[,file]       autosplit and process part n of m (VOB only) [off]
--cluster_percentage use percentage mode for cluster encoding -W [off]
--cluster_chunks a-b process chunk range instead of selected chunk [off]
 -S unit[,s1-s2]     process program stream unit[,s1-s2] sequences [0,all]
 -L n                seek to VOB stream offset nx2kB [0]

--import_v4l n[,id]  channel number and station number or name [0]

--pulldown           set MPEG 3:2 pulldown flags on export [off]
--encode_fields      enable field based encoding (if supported) [off]

--nav_seek file      use VOB navigation file [off]
--psu_mode           process VOB in PSU, -o is a filemask incl. %d [off]
--psu_chunks a-b     process only selected units a-b for PSU mode [all]
--no_split           encode to single file in chapter/psu mode [off]
--ts_pid 0xnn        transport video stream pid [0]

--a52_drc_off        disable liba52 dynamic range compression [enabled]
--a52_demux          demux AC3/A52 to separate channels [off]
--a52_dolby_off      disable liba52 dolby surround [enabled]

--print_status N[,r] print status every N frames / use CR or NL [1,1]
--progress_off       disable progress meter status line [off]
--color N            level of color in transcodes output [1]
--write_pid file     write pid of signal thread to "file" [off]
--nice N             set niceness to N [off]
--accel type         enforce IA32/AMD64 acceleration for type [autodetect]
--socket file        socket file for run-time control [no file]
--dv_yuy2_mode       libdv YUY2 mode (default is YV12) [off]
--config_dir dir     Assume config files are in this dir [off]
--ext vid,aud        Use these file extensions [.avi,.mp3]
--export_prof S      Export profile {vcd, svcd, xvcd,  dvd}[-pal|-ntsc|-secam]

 -q level            verbosity (0=quiet,1=info,2=debug) [1]
 -h                  this usage message
 -v                  print version

Forwarding MythFrontend to a remote MTD

While MythFrontend and MTD communication occur over a TCP connection to localhost (127.0.0.1), there is not a way to easily reconfigure this behavior. However, you can simply configure a port forward using xinetd to redirect traffic to any other IP address running MTD. This is potentially useful in the situation when it is preferred to rip a DVD on a dedicated backend server, where no mythfrontend is running but control the MythFrontend GUI from elsewhere.

Configure xinetd to redirect MTD

The easiest way to achieve this behavior is to simply employ xinetd. Xinetd will bind to a local port, and can be configured to forward to another IP address and port number. The default port for mtd is 2442. (However, this can be reconfigured in the MythFrontend settings)

To configure xinetd, simply place a file with the below contents in the directory /etc/xinetd.d/mtd-redirect Change the IP address and port number with the proper values of the mtd backend you wish to control.

# default: on 
# description: forward connections to 192.168.1.2:2442 
service mtd 
{ 
   socket_type = stream 
   wait = no 
   user = root 
   redirect = 192.168.1.2 2442 
   log_on_failure += USERID 
}

Next, you must configure /etc/services with a new entry for the mtd service. Append the following line to the bottom of the file. Again, change the port number as needed.

mtd             2442/tcp                        # Mythtv MTD service

Lastly, you must restart xinetd

/etc/init.d/xinetd restart

NOTE: If you are running IPtables on your mythbackend, make sure to open up port 2442 to your mythfrontends

WARNING: Due to the limitations of how the linux kernel works, it is not possible to force xinetd to listen only on the loopback adapter (127.0.0.1) THEREFORE, it is VERY important to firewall off (with either a router or linux IPtables) and block any traffic destined for 2442 from foreign hosts. Not doing so will allow outsiders a possible vector of attack into your network.

Database tables that configure MTD

Tables that configure mtd are part of the Category:DB Table: