July 2009 - MEncoder-users - lists.mplayerhq.hu

Help with MPG video encoding
by Walter Belhaven 20 Apr '13

20 Apr '13

Hi, I've got a question on how to get the best possible MPG encoding of a movie source, "at any price" so to speak -- i.e., as many bits as the encoder needs to get the highest possible video quality. It appears to me that the MPG encoding process is introducing artifacts that are present regardless of the amount of "free reign" I give to the encoder with respect to quantization, bitrate, and the like. My bottom line question is thus: "Are these artifacts inherent in MPG encoding, or am I just not twiddling the knobs and dials on the encoder correctly?" Here's all the details ... My source is a mixed hard- and soft-telecined "movie" at 1080/60i that I'm trying to tanscode to 480/24p, soft telecined to 480/60i, for ultimate burning to an NTSC DVD-Video. When I use mencoder to inverse telecine, crop out the crud, expand back to the original letterbox ratio (it's 2.35:1, not 16/9), and 'encode' the video with HUFFYUV (422P), the resulting video looks stunning, with no 'blocking' artifacts to speak of. This, of course, is as expected. But when I encode the video in MPG2 or MPG4, even with vqscale=1 or vqscale=2, I see sometimes severe blocking in the resulting video. Is this because the chroma is being subsampled vertically and horizontally (4:2:0), or is it because 'vqscale' is (perhaps necessary but) not sufficient to get "maximum quality at any price" encoding? Thanks, WB ____________________________________________________________________________________ Be a PS3 game guru. Get your game face on with the latest PS3 news and previews at Yahoo! Games. http://videogames.yahoo.com/platform?platform=120121

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B-frames and GOP with MPEG-2 for DVD
by Nicolas Hesler 16 Apr '11

16 Apr '11

Can anyone offer any input to the following command line? I've been trying to refine for the highest possible quality of MPEG-2 while staying DVD compliant. The source is 24fps. (Note: format=mpeg2, because format=dvd does not work with Adobe Encore 2.0). From what I understand, keeping GOP open, improves quality. Is this true? Is it 100% DVD compliant? Do I want to introduce B frames in my encoding? (The vb_strategy part of my command line is currently useless, right?) If parts of my video are reaching into 9-10 Mbs bitrate, would it beneficial to introduce B-Frames? Will it improve quality? (This is probably a stupid question) Are the sync issues with bframes only relevant to mpeg4 or lavf? mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=mpeg2:tsaf:telecine / -vf scale=720:480,harddup -mc 0 -noskip -srate 48000 -af lavcresample=48000:0:2 -lavcopts / vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=7000:vbitrate=6000:keyint=12 / :trell:mbd=2:precmp=2:subcmp=2:cmp=2:dia=-10:predia=-10:cbp:mv0:vqmin=1:lmin=1 / :dc=10:vpass=1:vb_strategy=2:acodec=ac3:abitrate=224:aspect=16/9:vstrict=0 -ofps 24000/1001 -o $output $input

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yadif: what does "spatial interlacing check" mean?
by Christian Ebert 29 Jun '10

29 Jun '10

Hi, TFM say about the 2 and 3 options for yadif that they "skip spatial interlacing check". What does this mean exactly? What's the better way to go if I want better quality regardless of encoding time? And would recommendations differ if I use yadif in connection with mcdeint? TIA c -- \black\trash movie _C O W B O Y_ _C A N O E_ _C O M A_ Ein deutscher Western/A German Western -->> http://www.blacktrash.org/underdogma/ccc.html -->> http://www.blacktrash.org/underdogma/ccc-en.html

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edl for transport stream
by Malte Schünemann 07 Nov '09

07 Nov '09

My receiver for TV programmes stores videos as transport stream. I tried cutting out scenes (e.g. commercials) using -edl - however, it seems that the transaport stream does not use seconds as time unit. Even edl scripts created via -edlout do not work - scenes cut out are different from what I selected before. Sure, I can re-encode using mencoder and do that job with the output file - in fact, this is what I am doing now. However, does anybody know how I can edit the transport stream properly ? It would spare me one long step of re-emcoding. Malte

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encoding video for the ipod 5g
by Sebastiaan van Erk 31 Jul '09

31 Jul '09

Hi, I know this question has been asked and answered 1000 times, and I searched the archives and tried pretty much everything I could find, but I still can't get it working. PROBLEM: My iPod only plays the audio track but does not show the video. DESCRIPTION: I tried both the MPEG4 and H264 codecs for video. The mencoder commands I used are listed below, and I make the mp4 file with mp4creator because the -of lavf -lavfopts format=mp4 was not working (even nautilus did not recognize the file when I created it with mencoder, it listed the codec as unknown; also gtkpod-aac refused to upload it to the ipod). So I used the procedure described in the mencoder docs at http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-quicktime-7.html#menc-feat-q… to create the final mp4. The commands I used: MPEG4: mencoder $INFILE -sws 9 -of avi -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=300 -o /tmp/$INFILE.$$ -oac faac -vf scale=320:-2,expand=320:240:0:0:1::,harddup -faacopts mpeg=4:br=128:object=2 -srate 44100 -channels 2 -sub $SUBS -subalign 0 -subpos 75 -ofps 25 mplayer /tmp/$INFILE.$$ -dumpvideo -dumpfile /tmp/$INFILE.$$.divx mplayer /tmp/$INFILE.$$ -dumpaudio -dumpfile /tmp/$INFILE.$$.aac mp4creator -create=/tmp/$INFILE.$$.divx -rate=25 $3 mp4creator -create=/tmp/$INFILE.$$.aac $3 mp4creator -list $OUTFILE rm -f /tmp/$INFILE.$$* When I do mp4creator -list I get: $ mp4creator -list sample.mp4 Track Type Info 1 video MPEG-4 Simple @ L1, 61.000 secs, 299 kbps, 320x240 @ 25.000000 fps 2 audio MPEG-4 AAC LC, 61.068 secs, 126 kbps, 44100 Hz When I look at the specs of the 5g at http://www.everymac.com/systems/apple/consumer_electronics/stats/ipod-5th-g… it seems to me it should be compatible: Video Support: Apple reports that the iPod 5GE models support "H.264 video, up to 1.5 Mbps, 640 by 480 pixels*, 30 frames per sec., Baseline Low-Complexity Profile with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats; H.264 video, up to 768 Kbps, 320 by 240 pixels, 30 frames per sec., Baseline Profile up to Level 1.3 with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats; MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per sec., Simple Profile with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats." H264: I also tried using H264, using the following commands: mencoder $INFILE -sws 9 -of avi -ovc x264 -x264encopts bitrate=300:vbv_maxrate=768:vbv_bufsize=244:nocabac:level_idc=13:me=umh:trellis=1:direct_pred=auto:level_idc=13:threads=2 -o /tmp/$INFILE.$$ -oac faac -vf scale=320:-2,expand=320:240:0:0:1::,harddup -faacopts mpeg=4:br=128:object=2 -srate 44100 -channels 2 -sub $2 -subalign 0 -subpos 75 -ofps 25 mplayer /tmp/$INFILE.$$ -dumpvideo -dumpfile /tmp/$INFILE.$$.h264 mplayer /tmp/$INFILE.$$ -dumpaudio -dumpfile /tmp/$INFILE.$$.aac mp4creator -create=/tmp/$INFILE.$$.h264 -rate=25 $3 mp4creator -create=/tmp/$INFILE.$$.aac $3 mp4creator -list $OUTFILE rm -f /tmp/$INFILE.$$* This gives a file which mp4creator -list describes as follows: $ mp4creator -list sample.mp4 Track Type Info 1 video H264 Baseline(a)1.3, 60.960 secs, 298 kbps, 320x240 @ 25.000000 fps 2 audio MPEG-4 AAC LC, 61.068 secs, 126 kbps, 44100 Hz OTHER INFO: My system info is: $ uname -a Linux blauwoor 2.6.27-14-generic #1 SMP Tue Jun 30 19:57:39 UTC 2009 i686 GNU/Linux $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 8.10 Release: 8.10 Codename: intrepid $ mencoder MEncoder 2:1.0~rc2-0ubuntu17+medibuntu1 (C) 2000-2007 MPlayer Team CPU: Genuine Intel(R) CPU T2400 @ 1.83GHz (Family: 6, Model: 14, Stepping: 8) CPUflags: Type: 6 MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1 Compiled with runtime CPU detection. No file given $ mp4creator -version mp4creator - mpeg4ip version 1.6 Any suggestions, tips, ideas are welcome. Thanks in advance, Sebastiaan

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Help on x264 and theora SSIM test
by Federico Pistono 30 Jul '09

30 Jul '09

Hi! I'm doing my thesis on Open Source encoding algorithms, and I was wondering if I could get some help from you. I need to make a few video comparisons between theora and h264, specifically for the web. The videos are the followings: http://people.xiph.org/~greg/video/y...omparison.html http://people.xiph.org/~maikmerten/youtube/ I know, they use youtube, which does not make the best h264 video at all, and it's possibly biased since they come from people at xiph, but it serves for the purpose of my thesis, which reflects online video in specific. I will also include a comparison of locally compressed video files, with the appropriate options, but I need both the crappy youtube and the good version to make a more accurate study. The comparisons I found by googling used the MSU Video Quality Measurement Tool, but I don't have any access to a Windows machine, and I'm having trouble compiling the java/c++ implementations from Zhou Wang's website: http://www.ece.uwaterloo.ca/~z70wang/research/ssim/ Also, the original source file is in matlab, but that only analyses freeze frames and at the moment I can't use matlab (I'll be away form the university for a while). If you ware wondering this is my machine configuration: Mac OS X Leopard MEncoder 1.0rc2-4.0.1 MPlayer 1.0rc2-4.0.1 FFmpeg version 0.5 x264 0.67.x I know, I should use the SVNs, but sometimes darwin ports are very convenient :P I asked the people at doom9, and I was advised to use AviSynth's SSIM filter by running avs2yuv with Wine. I would like to know if I can make a comparison between the original MPEG2 file, the x264 and the theora comparison without having to depend on windows or strange hacks with wine. I was able to get the SSIM for x264 while doing the encoding (using the specific option), but not for theora. So my question really is: what iter should I follow in order to make this comparison in the best possible way using my machine? Should I use x264 directly or mencoder? What options would be the best for a web-oriented video comparison? And for theora? ffmpeg2theora? Thanks, Federico Pistono - Department of Computer Science - Verona, Italy Blog (EN): http://www.federicopistono.org Blog (IT): http://federicopistono.altervista.org AsianCineBlog: http://eigakyou.blogspot.com CineBlog: http://www.unicinema.org/?q=blog/1 Volontariato: http://www.grillibiellesi.org public gpg key: gpg --keyserver pgp.mit.edu --recv-key EC6B272A

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Converting ape and flac files to mp3
by JD 30 Jul '09

30 Jul '09

Dear All, I would like to convert a collection of audio files, some of which are encoded in flac and others in ape, to mp3. I would like to use maximum constant bitrate of 320 or higher. Could someone please show the command line to do so? Cheers, JD

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filmdint=io=5:20 for hybrid material
by Nathan Shearer 29 Jul '09

29 Jul '09

Hi, I have some 24p+30p hybrid material that is hard telecined into 30000/1001i. The 24p sections are simply telecined and the 30p sections are simply 30000/1001p (not interlaced in any way). I have a frankescript that converts this into a 120000/1001fps AVI file with null frames so I can mux it into an MKV file to get progressive VFR, but it's quite ugly, slow, unmaintainable, and hardly elegant. What I would like is something along the lines of this one-liner: $ mencoder -dvd-device Babylon5.iso dvd://1 -noskip -fps 30000/1001 -vf filmdint=io=5:20 -ofps 120000/1001 -ovc x264 -x264encopts qp=15 -oac copy -of avi -o vfr.avi Then I can simply mux that into MKV and the encode is finished. Are there any existing filters in mencode that can do this?

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picking up x264 library
by Matyas 28 Jul '09

28 Jul '09

I installed the latest x264 from git and I get: Well? > /usr/local/bin/x264 --version x264 0.68.1189 9d0b5e9 However when I encode with mencoder, the resulting avi file lists a different version: Well? > strings test.29433.avi | grep x264 x264 - core 65 r1073 6a4a9be... What am I doing wrong? Thanks. Matyas - Every hardware eventually breaks. Every software eventually works.

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EDL on MPEG-TS streams with a timestamp discontinuity
by Nicolas George 26 Jul '09

26 Jul '09

Hi. Is there a solution to transcode a part (using an EDL or any other method) of a MPEG-TS that has a timestamp discontinuity, like DVB-T streams? Regards, -- Nicolas George

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