October 2007 - 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

3 9

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

12 43

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

5 11

Problem with rc2 (not present in rc1)
by Jesus Altuve 19 Feb '08

19 Feb '08

I can replicate the problem when the source video frame rate is unespecified/wrong OR when the source has a VERY low frame rate (cell phone videos) The problem is this.. rc1 will encode *ANYTHING* to flv without any problems using the following command line: rc1 version command line. ------------------------------------- mencoder PLAYBACK_ESPECTACULAR.wmv -of lavf -lavfopts i_certify_that_my_video_stream_does_not_use_b_frames -oac mp3lame -ovc lavc -channels 2 -vf scale=320:240 -lameopts cbr:br=32 -lavcopts vcodec=flv:vbitrate=350:mbd=2:turbo:keyint=8 -srate 22050 -o output.flv but... if I use rc2 I experience a strange problem... rc2 version command line (same as above except for the -lavfopts option) ------------------------------------ mencoder PLAYBACK_ESPECTACULAR.wmv -of lavf -oac mp3lame -ovc lavc -channels 2 -vf scale=320:240 -lameopts cbr:br=32 -lavcopts vcodec=flv:vbitrate=350:mbd=2:turbo:keyint=8 -srate 22050 -o output.flv The problem with rc2 is this: If the source video has an 'incorrect' frame rate (I have a video that reports frame rate as 99999) then the resulting video plays too fast, so I decided to add to the rc2 command the -ofps 24 flag.. and bingo, it works.. because it limits the fps to 24... now, the ofps solves the problem when the source FPS is too high/wrong.. however, if the source FPS is too low (cell phone videos) the encoded video will play too fast.. My problem is that this does NOT happen with rc1!! is there a way to tell mencoder to 'limit' the FPS to a certain value but ONLY if the source FPS is above *THAT* value? I already tried -fps -ofps, -mc 0 I still have to experiment with -noskip Thanks!

2 1

Performance on multi core machines - a specific enquiry re avisynth mt input
by Michael Rozdoba 13 Nov '07

13 Nov '07

First off, I hope this is an appropriate place to post this query. My apologies if I'm mistaken. I'm using mencoder under Windows XP as part of Megui. This is to encode to x264 2 pass, however as the input is an avisynth script which is very slow I'm performing a pre-render step where mencoder is used to transform the source via avisynth into an ffvhuff avi, which is itself subsequently passed into the 2 pass x264 encode. As the avisynth script is slow & avisynth natively doesn't make use of multi core cpus I'm using the mt (0.7) extension, which enables multithreading & exploitation of all cores. The script is fine. I can feed it to several players which will render it on my Q6600 box at about 11fps at 100% cpu utilisation. Without the mt extension I get 3fps at 25% cpu. I can even used VirtualDubMod & FFDShow to create a huffy avi encode from it, again at about 11fps, 100% cpu. However when I use mencoder it /all/ seems to be restricted to a single core & I only get 3fps 25% cpu. Can anyone explain what's going on & if this problem is unavoidable? Regardless of whether mencoder performs the huffy encode using multiple threads & cores, I did expect the framserving to its input to continue to exploit all four cores. Am I naively mistaken? Any comments, solutions or workarounds gratefully appreciated. For reference, though it's probably irrelevant, this is the mencoder cmd line: C:\Program Files\megui\tools\mencoder>mencoder.exe "E:\Work\test\fm-deblock.avs" -o "E:\Work\test\hfyu_fm-deblock.avi" -of avi -forceidx -ovc lavc -lavcopts vco dec=ffvhuff:vstrict=-2:pred=2:context=1 Here's the full output: MEncoder dev-SVN-r23107-4.3.0 (C) 2000-2007 MPlayer Team CPU: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz (Family: 6, Model: 15, Step ping: 11) CPUflags: Type: 6 MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 0 SSE2: 0 Compiled with runtime CPU detection. success: format: 0 data: 0x0 - 0x605 AVS file format detected. VIDEO: [YV12] 720x576 12bpp 25.000 fps 0.0 kbps ( 0.0 kbyte/s) [V] filefmt:38 fourcc:0x32315659 size:720x576 fps:25.00 ftime:=0.0400 Opening video filter: [expand osd=1] Expand: -1 x -1, -1 ; -1, osd: 1, aspect: 0.000000, round: 1 ========================================================================== Opening video decoder: [raw] RAW Uncompressed Video 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. videocodec: libavcodec (720x576 fourcc=48564646 [FFVH]) Selected video codec: [rawyv12] vfm: raw (RAW 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. Writing header... ODML: Aspect information not (yet?) available or unspecified, not writing vprp h eader. Writing header... ODML: Aspect information not (yet?) available or unspecified, not writing vprp h eader. Pos: 18.7s 467f ( 0%) 2.89fps Trem: 0min 0mb A-V:0.000 [33541:0] And just for completion, here's the avisynth script: SetMTMode(2,0) # Set DAR in encoder to 37 : 20. The following line is for automatic signalling global MeGUI_darx = 37 global MeGUI_dary = 20 DGDecode_mpeg2source("E:\Work\test\FM.d2v", info=3) ColorMatrix(hints=true,interlaced=true) #Not doing anything because the source is progressive crop( 0, 0, 0, 0) # from: http://forum.doom9.org/showthread.php?t=119486&page=2 # Purpose: clean up blocky/noisy mpeg2 source source = last backward_vec2 = source.MVAnalyse(isb = true, delta = 2, pel = 2, overlap=4, sharp=2, idx = 1, truemotion=true) backward_vec1 = source.MVAnalyse(isb = true, delta = 1, pel = 2, overlap=4, sharp=2, idx = 1, truemotion=true) forward_vec1 = source.MVAnalyse(isb = false, delta = 1, pel = 2, overlap=4, sharp=2, idx = 1, truemotion=true) forward_vec2 = source.MVAnalyse(isb = false, delta = 2, pel = 2, overlap=4, sharp=2, idx = 1, truemotion=true) mask = mvmask(kind=1, vectors=forward_vec1).UtoY().spline36resize(source.width(), source.height()) smooth = source.degrainmedian(mode=3).fft3dfilter(bw=16, bh=16, bt=3, sigma=4, plane=0) source2 = mt_merge(source, smooth, mask) source3 = source2.MVDegrain2(backward_vec1,forward_vec1,backward_vec2,forward_vec2,thSAD=400,idx=2) source3.gradfun2db(1.5) # Trim to a short clip for test purposes __film = last __t0 = __film.trim(120776, 122325) __t0 -- Michael Rozdoba

6 23

how to split 8gb wmv bluray wmv file (VC-1 codec)
by Valent Turkovic 02 Nov '07

02 Nov '07

Hi, how can I split large 8GB file to a few smaller ones using mencoder? As I can see the issue is that wmv uses Variable Frame Rate (VFR) and that is mainly the issue... The file I use is 2h long, and I can make the split of the first hour but I can't make the split from 1st hour till the end... mencoder -oac copy -ovc copy -o ./Part1.wmv -endpos 01:00:00 ./bluray_full_movie.wmv but when I try this: mencoder -oac copy -ovc copy -o ./Part2.wmv -ss 01:00:00 ./bluray_full_movie.wmv it fails :( 40 duplicate frame(s)! Pos: 86.2s 2066f (69%) 749.91fps Trem: 0min 110mb A-V:0.000 [7374:0] 41 duplicate frame(s)! Pos: 86.2s 2067f (69%) 750.00fps Trem: 0min 110mb A-V:0.000 [7376:0] 41 duplicate frame(s)! Pos: 86.3s 2068f (69%) 750.09fps Trem: 0min 110mb A-V:0.000 [7375:0] 40 duplicate frame(s)! Pos: 86.3s 2069f (69%) 750.45fps Trem: 0min 110mb A-V:0.000 [7378:0] 41 duplicate frame(s)! Pos: 86.3s 2070f (69%) 750.54fps Trem: 0min 110mb A-V:0.000 [7377:0] Too many audio packets in the buffer: (256 in 8388608 bytes). Maybe you are playing a non-interleaved stream/file or the codec failed? For AVI files, try to force non-interleaved mode with the -ni option. 41 duplicate frame(s)! Pos: 86.4s 2071f (69%) 750.36fps Trem: 0min 111mb A-V:0.000 [7379:0] Too many audio packets in the buffer: (256 in 8388608 bytes). Maybe you are playing a non-interleaved stream/file or the codec failed? For AVI files, try to force non-interleaved mode with the -ni option. Writing index... Writing header... ODML: Aspect information not (yet?) available or unspecified, not writing vprp header. Video stream: 7379.353 kbit/s (922419 B/s) size: 79675798 bytes 86.377 secs 2071 frames -- http://kernelreloaded.blog385.com/ linux, blog, anime, spirituality, windsurf, wireless registered as user #367004 with the Linux Counter, http://counter.li.org. ICQ: 2125241, Skype: valent.turkovic

3 4

Quicktime compatible - with ability to seek to next and previous frame quickly
by Nicolas Hesler 01 Nov '07

01 Nov '07

Is there a way to encode Quicktime compatible mp4's with the ability to seek backward [quickly] one frame at a time? Using a command line, like the following, I can create Quicktime compatible files, but I'm not able to seek quickly backward one frame at a time through the file. It does work but it's rather slow. Seeking one frame at a time forward quickly works fine. If you look at the HD Apple Trailers (like http://www.apple.com/trailers/touchstone/stepup2thestreets/ for example), you are able to seek backward and forward one frame at a time (using the arrow keys) and it's very responsive. I'd like to achieve that same responsiveness in seeking backward one frame at a time using mencoder. Any input or suggestions? mencoder input.avi -sws 9 -of lavf -lavfopts format=mp4 -vf scale=720:540,harddup -ovc x264 -x264encopts bitrate=4000:vbv_maxrate=5500:vbv_bufsize=3500:me=umh:subq=6:trellis=1:global_header:pass=1 -oac faac -faacopts mpeg=4:object=2:br=160:raw -channels 2 -srate 48000 -o output.mp4

2 3

ASS and mencoder: why?
by Nicolas George 31 Oct '07

31 Oct '07

Hi. It is known that ASS does not work with mencoder. But what is the reason about it? Is it just because nobody took the time to code it, or is there a deeper reason that makes it difficult to implement? Regards, -- Nicolas George

2 1

Generating switchable binary subtitles with MEncoder
by Francois Visagie 30 Oct '07

30 Oct '07

Dear All, I'm probably being stoopit but confirming that would already help. About the -vobsubout option the manual says: "Specify the basename for the output .idx and .sub files. This turns off subtitle rendering in the encoded movie and diverts it to VOBsub subtitle files." This only redirects VOBsub input, right? I was hoping to capture MEncoder's beautiful rendering of text subtitle input for use in DVD authoring this way, but alas it doesn't seem to work? Is there any way of capturing or exporting MEncoder subtitle rendering to some commonly used binary authoring format? Thanks, Francois

4 12

Generating switchable binary subtitles with MEncoder
by Francois Visagie 29 Oct '07

29 Oct '07

Dear All, I'm probably being stoopit but confirming that would already help. About the -vobsubout option the manual says: "Specify the basename for the output .idx and .sub files. This turns off subtitle rendering in the encoded movie and diverts it to VOBsub subtitle files." This only redirects VOBsub input, right? I was hoping to capture MEncoder's beautiful rendering of text subtitle input for use in DVD authoring this way, but alas it doesn't seem to work? Is there any way of capturing or exporting MEncoder subtitle rendering to some commonly used binary authoring format? Thanks, Francois

1 0