February 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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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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"High Quality" H.264 at low bit rates ;)
by Gunter Ohrner 04 Mar '08

04 Mar '08

Hi! I'm tyring to recode some MPEG2 streams to H.264 using mencoder and x264enc, my aim is to reduce the size significantly without a too severe quality loss. (Of course I'm aware that I'll lose quality in a lossy-to-lossy recoding in any case.) I'm using a post 1.0.rc2 mencoder (binary build of an svn snapshot from 20071207). What bitrate reduction factor should I be able to achieve? I'm asking as I read http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-x264.html, the mencoder man page and http://en.wikipedia.org/wiki/H264 . For my tests, I'm using bitrate-based three-pass encoding with variing encoding parameters. My source material is an 9.8 MBit MPEG2 stream. If I encode to 4 MBit H.264, there are still significant visual artifacts and a significant loss of detail in comparison to the source material. As I read that H.264 aims for at least twice the coding efficiency of MPEG2 or more, I wonder if this is correct and to be expected, or what encoding parameters have proven themselves to optimize the perceived visual quality? There's probably no way to aim for 2 mbit H.264 video without experiencing severy quality losses, right? Greetings, Gunter

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Re: [MEncoder-users] MEncoder-users Digest, Vol 42, Issue 41
by David Portabella Clotet 29 Feb '08

29 Feb '08

> > What is the most standard video format? > > Mpeg-1 video with mp2 audio, constant bitrate and no B frames, with a > standard framerate (24000/1001, 24, 25, 30000/1001, or 30) and > resolution (320x240 or 352x240 for NTSC; 320x288 or 352x288 for PAL). > Use the lavf encoders and muxer. This should be playable even on crap > like WMP and of course also on all good players. > > Rich > Hey, it works! I tried the following, that I found in http://lists.mplayerhq.hu/pipermail/mencoder-users/2007-April/005683.html mencoder SANY0271.MP4 -of mpeg -ovc lavc -lavcopts vcodec=mpeg1video:vbitrate=1000 -mpegopts format=mpeg1 -ofps 25 -oac lavc -lavcopts acodec=mp2:abitrate=224 -vf harddup -o test.mpg and I simplified to the following, still working: mencoder SANY0271.MP4 -of mpeg -ovc lavc -lavcopts vcodec=mpeg1video -mpegopts format=mpeg1 -oac lavc -lavcopts acodec=mp2 -o test.mpg Many thanks, DAvid ps: >From: Dominik 'Rathann' Mierzejewski >PS. You're breaking threading and top-replying. Please stop doing that. >I've fixed quoting in your reply just this once. I receive digested emails, so I cannot conserve the "Message-ID" of the individual reply. I also changed the "subject" of the email, as someone complained that the first I set was not meaningful. I hope now it is ok. Regards, DAvid

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anamorphic quicktime .mov detected with wrong aspect ratio
by Bram 29 Feb '08

29 Feb '08

Hey, I havea .mov file which plays with the correct aspect ratio (wide screen, 16:9 ? ) with apple's quicktime application. Mplayer/mencoder do not detect this aspect ratio; the PAR is set to 1:1 in the input file. As such, files converted with mencoder will have the wrong aspect ratio. The start of the file is here: http://bram.name/~brama/anamorphic.mov Output from mplayer: MPlayer dev-SVN-r25958-4.1.2 (C) 2000-2008 MPlayer Team CPU: AMD Athlon(tm)64 X2 Dual Core Processor 3800+ (Family: 15, Model: 43, Stepping: 1) CPUflags: MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 1 Compiled for x86 CPU with extensions: MMX MMX2 3DNow 3DNowEx SSE SSE2 Playing anamorphic.mov. libavformat file format detected. [mov,mp4,m4a,3gp,3g2,mj2 @ 0x8802ef4]negative ctts, ignoring [lavf] Audio stream found, -aid 0 [lavf] Video stream found, -vid 1 VIDEO: [avc1] 720x576 24bpp 25.000 fps 0.0 kbps ( 0.0 kbyte/s) [VO_XV] Could not grab port 355. ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264) ========================================================================== Opening audio decoder: [pcm] Uncompressed PCM audio decoder AUDIO: 48000 Hz, 2 ch, s16be, 0.0 kbit/0.00% (ratio: 0->192000) Selected audio codec: [pcm] afm: pcm (Uncompressed PCM) ========================================================================== [AO_ALSA] alsa-lib: pcm_hw.c:1242:(snd_pcm_hw_open) open /dev/snd/pcmC0D0p failed: Device or resource busy [AO_ALSA] alsa-lib: pcm_dmix.c:864:(snd_pcm_dmix_open) unable to open slave [AO_ALSA] Playback open error: Device or resource busy Could not open/initialize audio device -> no sound. Audio: no sound Starting playback... VDec: vo config request - 720 x 576 (preferred colorspace: Planar YV12) VDec: using Planar YV12 as output csp (no 0) Movie-Aspect is undefined - no prescaling applied. VO: [xv] 720x576 => 720x576 Planar YV12 New_Face failed. Maybe the font path is wrong. Please supply the text font file (~/.mplayer/subfont.ttf). subtitle font: load_sub_face failed. New_Face failed. Maybe the font path is wrong. Please supply the text font file (~/.mplayer/subfont.ttf). subtitle font: load_sub_face failed. V: 1.1 0/ 0 27% 2% 0.0% 0 0 Exiting... (Quit) Best regards, Bram.

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Flashvideo for YouTube using mencoder
by Ben 28 Feb '08

28 Feb '08

Hi, I've been using mencoder to publish video on YouTube quite succesfully by uploading FLV files under 350 kbit/s so that YouTube does not convert them. I'm just posting here what I think works really well, and would like to improve quality further if possible. My source is usually a HuffYUV lossless avi created using ffdshow, both video and audio have already been filtered and resized/scaled/resampled, so basically I only want the best transfer/conversion to FLV1, and for that I prefer to use mencoder. Here's an example encode command: mencoder.exe lillydave.avi -o lillydave.flv -mc 0 -ofps 29.97 -srate 44100 -oac mp3lame -lameopts vbr=2:q=8:aq=0:mode=1:lowpassfreq=16000 -ovc lavc -of lavf -lavfopts format=flv -lavcopts vcodec=flv:vbitrate=261:keyint=148: mbd=2:mv0:trell:v4mv:cbp:last_pred=3:predia=2:dia=2:precmp=2:cmp=2:subcmp=2:preme=2 The result of which was; http://youtube.com/watch?v=DYbibozTnWk I prefer to use 24 or 25 frames/sec, but in this example I have maintained framerate all the way to the flv, and the original was 29.970 fps. A+V streamrate of this example is 349 kbit/s, so YouTube left it alone. OK, any improvement on these choices of commands is welcomed! To be complete, the CLI output of encoding this: ------------------------------------------------- MEncoder Sherpya-SVN-r25513-4.2.2 (C) 2000-2007 MPlayer Team CPU: Intel(R) Pentium(R) D CPU 3.60GHz (Family: 15, Model: 6, Stepping: 4) CPUflags: Type: 15 MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1 Compiled with runtime CPU detection. Cannot load bitmap font: c:\WINdows\Fonts\immortal.fon success: format: 0 data: 0x0 - 0x73314704 AVI file format detected. [aviheader] Video stream found, -vid 0 [aviheader] Audio stream found, -aid 1 VIDEO: [HFYU] 448x336 24bpp 29.970 fps 26858.9 kbps (3278.7 kbyte/s) [V] filefmt:3 fourcc:0x55594648 size:448x336 fps:29.97 ftime:=0.0334 ========================================================================== Opening audio decoder: [pcm] Uncompressed PCM audio decoder AUDIO: 44100 Hz, 2 ch, s16le, 1411.2 kbit/100.00% (ratio: 176400->176400) Selected audio codec: [pcm] afm: pcm (Uncompressed PCM) ========================================================================== ** MUXER_LAVF ***************************************************************** REMEMBER: MEncoder's libavformat muxing is presently broken and can generate INCORRECT files in the presence of B frames. Moreover, due to bugs MPlayer will play these INCORRECT files as if nothing were wrong! ******************************************************************************* OK, exit Opening video filter: [expand osd=1] Expand: -1 x -1, -1 ; -1, osd: 1, aspect: 0.000000, round: 1 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffhuffyuv] vfm: ffmpeg (FFmpeg HuffYUV) ========================================================================== MP3 audio selected. VDec: vo config request - 448 x 336 (preferred colorspace: Planar YV12) VDec: using Planar YV12 as output csp (no 2) Movie-Aspect is undefined - no prescaling applied. videocodec: libavcodec (448x336 fourcc=31564c46 [FLV1]) [VE_LAVC] High quality encoding selected (non-realtime)! VIDEO CODEC ID: 22 AUDIO CODEC ID: 15001, TAG: 0 Writing header... Pos: 546.5s 16380f (100%) 22.83fps Trem: 0min 22mb A-V:0.000 [262:77] Flushing video frames. Writing index... Video stream: 262.658 kbit/s (32832 B/s) size: 17944325 bytes 546.547 secs 16380 f rames Audio stream: 77.401 kbit/s (9675 B/s) size: 5287509 bytes 546.508 secs ------------------------------------------------- Btw; What's with the font-notice? I don't need a font in a commandline shell.. Regards, and thanks for this amazing encoder! JB

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What is the most standard video format?
by David Portabella Clotet 28 Feb '08

28 Feb '08

Thanks for answering. I tried to rename the .MP4 to .MOV, but Windows Media Player still does not play it. What is the most standard video format? I've tried an AVI file with no compression: > mencoder SANY0271.MP4 -o SANY0271.avi -of avi -oac pcm -ovc raw but Windows Media Player still does not play it. VLC plays it ok. and a MPEG1 as follows: > mencoder SANY0271.MP4 -o test.mpg -of mpeg -oac lavc -ovc lavc -lavcopts vcodec=mpeg1video Windows Media Player plays it, but the video is all black without audio neither. VLC plays it ok. What is the most standard video format? one that Microsoft Media Player can play without additional codecs? Many thanks, DAvid > David Portabella Clotet wrote: > > Hello, > > Hello - I don't understand the subject of your new email thread. Always > best to create a new message and not just reply to something random. > > > I have a video from my video camera, in .MP4 file format. > > > > I'd like to upload it to Picasa Web which accepts MPG, AVI, ASF, WMV, MOV, > > and 3gp. > > http://picasa.google.com/support/bin/answer.py?answer=23832 > > Try just renaming the .MP4 file to .MOV. > > .MP4 file format is based on the .MOV file format and you might just get > away with pretending your .MP4 is a .MOV. > > Do let us know how you get on. > > -- > Mark

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Conversion of 720p mpeg capture from 60 fps to 30 fps where original was 24 fps
by Laine Lee 28 Feb '08

28 Feb '08

I routinely have 1280X720 mpeg files recorded via ATSC using an EyeTV device along with EyeTV software that I want to record to DVD (standard format, usually dual layer capacity). In most cases the original content for these broadcasts are movies with a probably original frame rate of 24 fps. I've gathered information on this type of conversion from this list and elsewhere since I started using the EyeTV device because the commercial method promoted by the manufacturer of the device and accompanying software is not very robust for this particular kind of conversion. I have a command line that yields fair results, but it's not ideal, because although low motion passages look great, panning motion passages aren't coming out as smooth as in the original 60 fps input file, and the time needed to make the conversion for a typical feature length movie capture is excessive. Please offer any suggestions you care to make about how to improve it. An example command line is included below. It's 2 pass. Thanks. mencoder -oac copy -ovc lavc -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9000:vbitrate=7600:vrc_eq=te x^qComp:keyint=18:trell:mbd=2:precmp=2:subcmp=3:cmp=3:dia=-10:predia=-10:cbp :mv0:vqmin=1:lmin=1:dc=10:vstrict=0:aspect=16/9:vpass=1:turbo -vf tinterlace=2,pullup=8:8:8:8:-1:1,softskip,hqdn3d=2:1:2,pp=fd,scale=720:480,h arddup -of mpeg -mpegopts format=dvd:tsaf -ofps 30000/1001 -o /dev/null /Users/me/input.mpg && mencoder -oac copy -ovc lavc -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9000:vbitrate=7600:vrc_eq=te x^qComp:keyint=18:trell:mbd=2:precmp=2:subcmp=3:cmp=3:dia=-10:predia=-10:cbp :mv0:vqmin=1:lmin=1:dc=10:vstrict=0:aspect=16/9:vpass=2 -vf tinterlace=2,pullup=8:8:8:8:-1:1,softskip,hqdn3d=2:1:2,pp=fd,scale=720:480,h arddup -of mpeg -mpegopts format=dvd:tsaf -ofps 30000/1001 -o /Users/me/output.mpg /Users/me/input.mpg -- Laine

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