March 2008 - 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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2pass: auto-calculation of bitrate?
by Ilya Zakharevich 25 Nov '08

25 Nov '08

I'm looking for a way to let mencoder (I use xvid) to automatically select the 2-pass average video bitrate based on the contents. I'm pretty sure that most (if not the all) of the logic to do it is already there, but I can't find the UI to trigger this behaviour. A) For example: suppose I have 100 videos; now a) append them all together; b) do 2-pass encoding of them all with, e.g., 1200kb/sec bitrate; c) split the result into 100 video files. This way, mencoder will automatically assign some "appropriate" average bitrate to each video. B) Now suppose that I have only 1 video, but I have all 100 logs of pass=1 for all 100 videos. Theoretically, this is all which is needed to do an equivalent of a/b/c for this particular video. How to convince mencoder to use these extra log files? C) Now suppose that I have only 1 video, and only 1 log of pass=1 for this video. It is more or less obvious that all I need from the remaining 99 logs is very short "summaries". How to create the summaries, and how to "feed" them to mencoder? D) And now the last logical step: If of these 99 remaining videos 40% is "action-like", 40% is "arthouse-like", and 20% is animation, then law of big numbers starts to be applicable. Essentially, I won't need to have summaries of the particular videos; I could feed in 40 copies of "average action-like summary", 40 copies of "average arthouse-like summary", and 20 copies of "average animation summary". So if I keep these summaries in ~/.mplayer in action.sum arthouse.sum animation.sum, then I could ask mencoder to do bitrate_from=1200,40*action+40*arthouse+20*animation and it could choose the appropriate bitrate. Is it possible to do now (possibly, with some pre-processing)? Any plans to have this? Thanks, Ilya

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converting and subtitle questions !
by zechao wang 20 Apr '08

20 Apr '08

Hello Everyone! There have two questions need your help: (1) To convert rmvb to mp4 for my cellphone, i had to convert two times. First, rmvb should be converted to avi with mencoder; Second, avi could be converted to mp4 wth ffmpeg . My commands are: mencoder mov.rmvb -ovc lavc -oac mp3lame -o mov.avi ffmpeg -y -i mov.avi -vcodec xvid -s 400x240 -r 29.97 -b 600 -acodec aac -ac 2 -ar 48000 -ab 128 -vol 200 -f mp4 mov.mp4 Is there a way to do that just with mencoder in one time ? If it can, please tell me the command ( i have tried much times, but failed all the time) ! (2) After adding subtitles to movie with mencoder, only striping (--) could be seen when playing! I'm sure the subtitle can works well when it working with the movie together. The language of the subtitle file is simple chinese and the encoder mode is utf8. My command is: mencoder test.avi -ovc lavc -oac copy -sub test.srt -font "/usr/share/fonts/truetype/arphic/uming.ttf" -subcp utf8 -subfont-encoding unicode -subfont-text-scale 3 new.avi I don't know why, please tell me if somebody know. --------------------------------- 雅虎邮箱传递新年祝福，个性贺卡送亲朋！

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Ripping dvd to mp4
by Erik Slagter 07 Apr '08

07 Apr '08

Hi, I want to be able to rip dvd's and play them on my PS3 (and also other future, standards-compliant hardware devices, so this rules out ogg, matroska etc.) The nasty thing is that I also want exactly 1 subtitle track included. Without subtitling it is actually very simple to rip a dvd... I also found out that mp4 does support (soft) subtitling but most devices do not render them, so I will need to render the subtitles in the video stream :-( Also the audio and video need to remain in sync (of course) wich rules out solutions that use elementary streams without a/v sync compensation. As far as I know there is only one combination of programs and options that can do this (see attached script), which works fairly well. It uses the command line versions of x264 and faac to achieve maximum flexibility. The audio and video frames are passed using named pipes so there are no huge intermediate files. The stdin-stdout pipes are only there to keep all processes running while there is still input to be processed, no data is passed through them. It adds chapter info to the mp4 file although the PS3 doesn't use it :-( I was wondering whether someone knows other (simpler) solutions as well. Native subtitling rendering support in ffmpeg and mencoder would the best solution of course, but that's not reality. ============================================== #!/bin/sh audiolang="en" sublang="nl" if [ $# -lt 1 ] then dvd=$PWD else dvd="$1" fi if [ ! -d "$dvd" ] then echo "not a directory: $1" exit fi vpipe1="dvd2avc1.y4m" apipe1="dvd2avc1.apipe" title=$(mplayer -identify -frames 0 -dvd-device $dvd dvd:// 2>&1 | egrep "ID_DVD_TITLE_[0-9]+_LENGTH=" | sort '-t=' -g -r -k 2 | head -1 | \ perl -n -e '($_) = m/ID_DVD_TITLE_([0-9]+)_LENGTH/; print $_') echo "Main title: $title" chapters=$(mplayer -identify -frames 0 -dvd-device $dvd dvd://${title} 2>&1 | perl -n -e 'if(/^CHAPTERS: /) { s/^CHAPTERS: //; s/,/ /g; print $_; last; }') echo "Chapters in this title: $chapters" aid=$(mplayer -identify -frames 0 -dvd-device $dvd dvd://${title} 2>&1 | egrep "ID_AID_[0-9]+_LANG=${audiolang}" | sort -g | head -1 | \ perl -n -e '($_) = m/ID_AID_([0-9]+)_LANG/; print $_') echo "Audio id: $aid" sid=$(mplayer -identify -frames 0 -dvd-device $dvd dvd:// 2>&1 | \ perl -n -e "if(/ID_SID_[0-9]+_LANG=${sublang}/) { (\$a) = m/ID_SID_([0-9])+_LANG/; printf \"%s\n\", \$a; }") echo "Sub id: $sid" avc="dvd.264" aac="dvd.aac" mp4="dvd.mp4" chap="dvd.chap" rm "$vpipe1" "$apipe1" 2> /dev/null mknod "$vpipe1" p mknod "$apipe1" p rm "$chap" 2> /dev/null for chapter in $chapters do echo "$chapter $chapter" >> $chap done mplayer -noconsolecontrols -nocache -vf-clr -benchmark -slang nl -sid "$sid" -aid "$aid" \ -vo "yuv4mpeg:interlaced:file=$vpipe1" -ao "pcm:waveheader:file=$apipe1:fast" \ -dvd-device $dvd dvd://$title 1>&2 /dev/null | \ x264 --bframes 16 --b-pyramid --ref 4 --interlaced --crf 20 \ --trellis 1 --nr 1000 --level 41 \ --threads 2 --direct none --subme 5 -o "$avc" "$vpipe1" | \ (faac --mpeg-vers 4 -b 192 -o "$aac" "$apipe1" 2> /dev/null) rm "$vpipe1" "$apipe1" 2> /dev/null MP4Box -lang en -new "$mp4" -add "$avc" -add "$aac" -chap "$chap" -isma

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Re: [MEncoder-users] Newbie struggling with pullup
by Rich Felker 31 Mar '08

31 Mar '08

On Wed, Feb 27, 2008 at 10:13:59PM -0600, Laine Lee wrote: > On 2/27/08 8:04 PM, "Rich Felker" <dalias(a)aerifal.cx> wrote: > > > No, 1280x720 @ 60 fps is progressive content with duplicated frames, > > rather than (field-based) telecine. You can either use the decimate > > filter with the right settings (and the right -ofps) to remove the > > duplicate frames, or use the tinterlace=4 filter prior to pullup to > > convert to normal telecine which pullup can handle. The latter > > approach is probably better. > > Thanks. I had already stumbled onto that tinterlace=4 before pullup but am > still trying to refine it. Actually, the following filter chain resulted in > the fewest reports of skipped or duplicated frames. > > tinterlace=2,pullup=8:8:8:8:-1:1,softskip,hqdn3d=2:1:2,pp=fd,scale=720:480,h > arddup > > But in 30000/1001 output, I always see a pattern of 5 frames with the 4th > and 5th being similar (duplicate). Would decimate have a better chance of > giving me output with only unique frames? The output is not supposed to be 30000/1001 but 24000/1001, so what you're seeing is perfectly natural. Just fix the ofps. And please keep replies on-list, ALWAYS. Rich

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wmv audio codecs support at linux 64 bit system?
by martinnitram 30 Mar '08

30 Mar '08

Dear all, At 32 bit system (FC 3), after put window codecs files (http://www.mplayerhq.hu/MPlayer/releases/codecs/windows-all-*.zip) to mplayer codecs directory (something like /usr/lib/win32/), then use can ffmpeg/mencoder to decode wmv video/audio to avi format. Now tried at 64 bit system (CentOS 5.1), even put those file to correct directory (64 bit one is /usr/lib64/codecs/, which rpm from DAG), it seem ffmpeg/mencoder can't use those file to decode wmv audio (it shown error "Cannot find codec for audio format 0x162" from mencoder ). From google, it seem that only win32 codecs file for mplayer, so it meaned that needed to remove the 64 bit version of mplayer and related package and then install 32 bit one? Thank a lot

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Re: [MEncoder-users] converting and subtitle questions
by zechao wang 27 Mar '08

27 Mar '08

zechao wang <wzc0066(a)yahoo.com.cn> 写道：日期: Thu, 27 Mar 2008 19:40:16 +0800 (CST) 发件人: zechao wang <wzc0066(a)yahoo.com.cn> 主题: Re: Re: [MEncoder-users] converting and subtitle questions 收件人: MEncoder usage discussions <mencoder-users(a)mplayerhq.hu> Hello, "Jorge Peixoto de Morais Neto", thank you very much really. You have given me so much advice . mencoder -ffourcc DX50 -o /dev/null -ovc lavc -vf scale=400:240,harddup -lavcopts vstrict=0:keyint=32:mbd=2:trell:v4mv:last_pred=3:predia=3:dia=3:cbp:preme=2:vbitrate=512:vpass=1:turbo -oac faac -faacopts br=128 mov.rmvb mencoder -ffourcc DX50 -o mov.avi -ovc lavc -vf scale=400:240,harddup -lavcopts vstrict=0:keyint=32:mbd=2:trell:v4mv:last_pred=3:predia=3:dia=3:cbp:preme=2:vbitrate=512:vpass=2 -oac faac -faacopts br=128 mov.rmvb MP4Box -aviraw audio mov.avi MP4Box -aviraw video mov.avi mv mov_audio.raw mov.aac mv mov_video.cmp mov.m4v MP4Box -add mov.aac -add mov.m4v mov.mp4 The quality of the mp4 file is good, but still can not be played in phone. May be the MP4Box was used in a wrong way, anyone who can tell me how to use it correctly . Thanks. Jorge Peixoto de Morais Neto <please.no.spam.here(a)gmail.com> 写道： On Wed, Mar 26, 2008 at 2:54 AM, Jorge Peixoto de Morais Neto wrote: > 2008/3/21 zechao wang : > > > But file mymov.mp4 could not be played in my cellphone! > > Please give me some advice, thank you very much. > When encoding with mencoder, use the option -ffourcc DX50 . This is > sometimes necessary for your video to be recognized by a player (see > the man page for details). > Try these options, they have a greater chance of working (see the documentation for their meaning): First pass: mencoder -ffourcc DX50 -o mov.avi -ovc lavc -vf scale=400:240,harddup -lavcopts vstrict=0:keyint=32:mbd=2:trell:v4mv:last_pred=3:predia=3:dia=3:cbp:preme=2:vbitrate=512:vpass=1:turbo -oac faac -faacopts br=128 mov.rmvb Second pass: mencoder -ffourcc DX50 -o mov.avi -ovc lavc -vf scale=400:240,harddup -lavcopts vstrict=0:keyint=32:mbd=2:trell:v4mv:last_pred=3:predia=3:dia=3:cbp:preme=2:vbitrate=512:vpass=2 -oac faac -faacopts br=128 mov.rmvb _______________________________________________ MEncoder-users mailing list MEncoder-users(a)mplayerhq.hu https://lists.mplayerhq.hu/mailman/listinfo/mencoder-users --------------------------------- 雅虎邮箱，您的终生邮箱！ --------------------------------- 雅虎邮箱，您的终生邮箱！

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Downmixing and normalising
by Olivier Rolland 27 Mar '08

27 Mar '08

Hi, I want to encode a 5.1 DVD in a stereo avi with audio normalised. What is the best ways to get that: -channels 2 -af volnorm or -channels 2 -af channels=2,volnorm or -channels 2 -af volnorm=2,channels ? Can I omit "-channels 2" ? What is the precedence between -channels and -af ? Thanks, Olivier

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Encoding DVD for Window Mobile 6 Device
by Mitch Miller 26 Mar '08

26 Mar '08

I searched the archives and couldn't find this specifically, so I thought I'd ask. I have some training DVDs that I'd like to watch on my Windows Mobile 6 based HTC Mogul (6800) phone. I know it has a 320x240 display and runs Windows Media Player (mobile version), but can't seem to relate these to what command line options I need to use. Ideally, I'd like either a separate output file for each Title on the DVD that includes all the chapters of that title, or separate files for every title and chapter on the DVD. Then, I could simply create a playlist on my handheld and watch the videos. Would anyone care to take a shot at the command line options for this? Thanks in advance, -- Mitch P.S. The input would be directly from the DVD itself.

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