December 2010 - 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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Dolby downmix
by Rolf Ernst 01 Jan '11

01 Jan '11

Can someone clarify this for me, please? I am trying to do a Dolby Surround downmix from an AC3 5.1 a/v file. I have found many different comments from many different sources with many different observations and comments. Can someone clarify this for me? This is the command line I have seen that supposedly dumps the audio via filter as Dolby surround into a wav file. Is this true? mplayer inputfile -channels 6 -af channels=2 -vc null -vo null -ao pcm:fast:file=audio.wav -- /re

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Terrible results with x264
by Jason Cumiskey 29 Dec '10

29 Dec '10

Hi, I have just started using x264 to encode my dvds. I am going for quality, not speed. I am basing my -x264encopts off of the recommendations from http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-x264.html Here are the commands I issue (I am using 2 pass encode): mencoder -dvd-device /dev/dvd1 dvd://1 -alang eng -aid 128 -oac mp3lame -lameopts cbr:br=128:vol=7 -vf pullup,softskip,crop=704:480:10:0,hqdn3d=2:1:2,harddup -ovc x264 -x264encopts pass=1:bitrate=1400:subq=1:partitions=all:8x8dct:me=umh:frameref=1:bframes=3:b_pyramid=normal:weight_b:threads=auto -o movie.h264 # Pass 2 mencoder -dvd-device /dev/dvd1 dvd://1 -alang eng -aid 128 -oac mp3lame -lameopts cbr:br=128:vol=7 -vf pullup,softskip,crop=704:480:10:0,hqdn3d=2:1:2,harddup -ovc x264 -x264encopts pass=2:bitrate=1400:subq=6:partitions=all:8x8dct:me=umh:frameref=6:bframes=3:b_pyramid=normal:weight_b:threads=auto -o movie.h264 On pass 2, I change subq to 6 and frameref to 6 (as recommended in the docs link above to speed up 1st pass and have higher quality for 2nd pass).Can anyone see anything obviously wrong in my command chain? The resulting video is heavily pixelated and mplayer shows a bitrate of 0kbps. Jason Cumiskey

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improve saa7134 TV-card stream recording
by ivo.linux 28 Dec '10

28 Dec '10

Dear Friends I am trying to record saa7134 TV-card stream using mencoder. I used the following . ********* mencoder tv:// -tv driver=v4l2:device=/dev/video0:width=640:height=480:norm=PAL:alsa:adevice=hw.0 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=1500:vhq -vf pp=lb -oac mp3lame -lameopts br=128:cbr:mode=0 -o inter-roma.avi ********* I obtained a poor quality file. In detail: the video flow is discontinued (stop and go) and audio is not synchronized with the video This is a cutting of my terminal ********* 22 duplicate frame(s)! Pos: 32.2s 615f ( 0%) 19.48fps Trem: 0min 0mb A-V:0.000 [391:127] video buffer full - dropping frame video buffer full - dropping frame video buffer full - dropping frame ********* Thanks in advance for any help

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lavf floating point exception / dimensions not set
by Joseph Miller 25 Dec '10

25 Dec '10

I checked out mplayer on Dec 20, 2010. I keep getting the lavf floating point exception and I don't know what to do. Could someone point me in the right direction? /opt/mplayer/bin/mencoder -oac faac -ovc x264 -x264encopts qp=5:bframes=0 -o bbcl1-alldealers-cin.mp4 bbcl1-alldealers-web.mp4 -vf harddup -of lavf MEncoder SVN-r32724-4.4.5 (C) 2000-2010 MPlayer Team success: format: 0 data: 0x0 - 0x7bafca libavformat file format detected. [lavf] stream 0: video (h264), -vid 0 [lavf] stream 1: audio (mp3), -aid 0, -alang und VIDEO: [H264] 480x360 24bpp 29.970 fps 450.6 kbps (55.0 kbyte/s) [V] filefmt:44 fourcc:0x34363248 size:480x360 fps:29.970 ftime:=0.0334 ========================================================================== Opening audio decoder: [mp3lib] MPEG layer-2, layer-3 AUDIO: 22050 Hz, 2 ch, s16le, 8.0 kbit/1.13% (ratio: 1000->88200) Selected audio codec: [mp3] afm: mp3lib (mp3lib MPEG layer-2, layer-3) ========================================================================== ** 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 filter: [harddup] ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264) ========================================================================== Pos: 0.0s 1f ( 1%) 0.00fps Trem: 0min 0mb A-V:0.000 [0:0] 1 duplicate frame(s)! VIDEO CODEC ID: 28 AUDIO CODEC ID: 15002, TAG: 0 Writing header... [mp4 @ 0xda4da0]dimensions not set Floating point exception -Joseph

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Issues trying to concatenate video files
by Jim Wiggs 13 Dec '10

13 Dec '10

Folks, I'm using gtk-recordMyDesktop to do simple screen captures combined with voiceovers. As you may or may not know, recordMyDesktop saves in one format, and one only, and that is ogg theora ".ogv". I want to concatenate these videos with an existing .mp4 video using avidemux but I can't seem to get an exact matchup in terms of both the video and the audio streams so that I can successfully splice the files together. Here is the information about the original video: bash% ffmpeg -i TestVideo1.mp4 FFmpeg version 0.5-svn17737+3:0.svn20090303-1ubuntu6.2, Copyright (c) 2000-2009 Fabrice Bellard, et al. configuration: --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --extra-version=svn17737+3:0.svn20090303-1ubuntu6.2 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --disable-stripping --disable-vhook --enable-libdc1394 --disable-armv5te --disable-armv6 --disable-armv6t2 --disable-armvfp --disable-neon --disable-altivec --disable-vis --enable-shared --disable-static libavutil 49.15. 0 / 49.15. 0 libavcodec 52.20. 0 / 52.20. 0 libavformat 52.31. 0 / 52.31. 0 libavdevice 52. 1. 0 / 52. 1. 0 libavfilter 0. 4. 0 / 0. 4. 0 libswscale 0. 7. 1 / 0. 7. 1 libpostproc 51. 2. 0 / 51. 2. 0 built on Apr 23 2010 15:08:34, gcc: 4.3.3 Seems stream 0 codec frame rate differs from container frame rate: 30.00 (30/1) -> 15.00 (15/1) Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'TestVideo1.mp4': Duration: 01:44:08.48, start: 0.000000, bitrate: 110 kb/s Stream #0.0(eng): Video: h264, yuv420p, 640x480, 15 tbr, 15 tbn, 30 tbc Stream #0.1(eng): Audio: aac, 22050 Hz, stereo, s16 At least one output file must be specified And here is the info on the .ogv file: bash% ffmpeg -i Part1IntroSlide.ogv FFmpeg version 0.5-svn17737+3:0.svn20090303-1ubuntu6.2, Copyright (c) 2000-2009 Fabrice Bellard, et al. configuration: --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --extra-version=svn17737+3:0.svn20090303-1ubuntu6.2 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --disable-stripping --disable-vhook --enable-libdc1394 --disable-armv5te --disable-armv6 --disable-armv6t2 --disable-armvfp --disable-neon --disable-altivec --disable-vis --enable-shared --disable-static libavutil 49.15. 0 / 49.15. 0 libavcodec 52.20. 0 / 52.20. 0 libavformat 52.31. 0 / 52.31. 0 libavdevice 52. 1. 0 / 52. 1. 0 libavfilter 0. 4. 0 / 0. 4. 0 libswscale 0. 7. 1 / 0. 7. 1 libpostproc 51. 2. 0 / 51. 2. 0 built on Apr 23 2010 15:08:34, gcc: 4.3.3 [theora @ 0x8eaa520]7 bits left in packet 82 Input #0, ogg, from 'Part1IntroSlide.ogv': Duration: 00:02:20.53, start: 0.000000, bitrate: 631 kb/s Stream #0.0: Invalid Codec type -1 Stream #0.1: Video: theora, yuv420p, 640x480, PAR 1:1 DAR 4:3, 15 tbr, 15 tbn, 15 tbc Stream #0.2: Audio: vorbis, 48000 Hz, stereo, s16, 499 kb/s At least one output file must be specified My objective is simple: I have two .ogv files, one "Intro" and one "WrapUp", and I want to concatenate them with the .mp4 file to produce a single mp4 Intro -> Main Video -> WrapUp. I spent almost a day trying to do this by transcoding everything to mpeg1 format with mp2 audio, then concatenating the files. That "worked" but I ended up with audio/video sync issues, where the video would start leading the audio progressively more and more, plus there were audio dropouts, it was a mess. I got the same result when I concatenated using mencoder: mencoder -oac copy -ovc copy -of mpeg Part1IntroSlide.mpg TestVideo1.mpg Part1ClosingSlide.mpg -o SplicedVideo1.mpg It did not matter whether I used -forceidx or "-mc 0" or "-noskip" or any combination of these. Currently, I'm trying to transcode everything to the same format as the main video, then use avidemux to do the splicing. I keep getting the result that once I do the full concatenation, there is no audio. I can concatenate the starting and ending pieces but once I splice in the main audio, the end result is a file that has the precise video result I'm looking for but no sound. Can anyone help out, here? I'm running Ubuntu 9.04, but I have access to a 10.04 LTS box if I need it. I've got both mencoder and ffmpeg installed, as well as avidemux and the default totem video player to test videos once they are complete. I can provide additional information about the commands/parameters I've been experimenting with if needed. Just let me know. On the other hand, if anyone has already figured out a solution for this issue, that would be great to hear, too. many thanks, Jim

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Re: [MEncoder-users] Strange output format of mencoder
by briconaut＠gmx.de 12 Dec '10

12 Dec '10

Hi, thanks for the ideas and suggestions. I think I've now discovered the reason for the corrupt files: mencoder gets killed mid-encoding. I was abled to reproduce the strange video output format by sending SIGKILL to mencoder and I noticed that the bad files have a few minutes missing at the end. Unfortunately I'm not able to produce the effect without sending a SIGKILL. I've transcoded my bad files a second time and everything went fine. I assume the same effect is caused by mencoder dying because of a bug. But as long as I've got nothing more solid, I blame my own clumsiness for my problems. Thanks for the help, Thomas.

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Strange output format of mencoder
by briconaut＠gmx.de 11 Dec '10

11 Dec '10

Hi, I've been using mencoder to transcode videos for my iPad for some time without any problems. Recently some of the transcoded files were not usable anymore. Neither itunes nor the ipad could play them, but playing them with mplayer on my debian box still works. To understand this behavior, I took a good and a bad file and compared the output of 'mplayer -identify' of both the original and the transcoded file. While the original '-identify' output of the files is really similar, the '-identify' output for the transcoded files appears to be radically different (at least to my untrained eye). I'm posting the '-identify' output and my transcoding command below in the hope that someone might be able to answer these questions: - What is the difference in the input files that makes mencoder produce two so apparently different output formats? - How can I detetct this difference? The '-identify' option apparently doesn't show the crucial piece of information. - How can I encode my 'bad' files to get them to play just like the good ones. Thanks for any help and suggestions in advance, Thomas. My system: Debian/Lenny on 2.6.32-bpo.5-amd64 My mencoder version: MEncoder dev-SVN-r26940 (C) 2000-2008 MPlayer Team CPU: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz (Family: 6, Model: 23, Stepping: 10) CPUflags: Type: 6 MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1 Compiled with runtime CPU detection. My transcoding command: mencoder -sws 9 \ -of lavf \ -lavfopts format=mp4 \ -vf 'scale=1024:768,dsize=1024:-2,harddup' \ -ovc x264 \ -x264encopts 'bitrate=800:vbv_maxrate=1000:vbv_bufsize=2000:nocabac:me=umh:subq=6:frameref=6:trellis=1:level_idc=30:global_header:threads=2' \ -oac faac \ -faacopts 'mpeg=4:object=2:br=160:raw' \ -channels 2 -srate 24000 \ file.avi -o file.mp4 (Comments on how to do this better/right are welcome, I got this command from google...) Output of '-identify' on the original 'good' file: Playing good.avi. AVI file format detected. ID_VIDEO_ID=0 [aviheader] Video stream found, -vid 0 ID_AUDIO_ID=1 [aviheader] Audio stream found, -aid 1 VIDEO: [XVID] 624x352 12bpp 23.976 fps 1033.3 kbps (126.1 kbyte/s) Clip info: Software: MEncoder SVN-r32669-4.3.2 ID_CLIP_INFO_NAME0=Software ID_CLIP_INFO_VALUE0=MEncoder SVN-r32669-4.3.2 ID_CLIP_INFO_N=1 ID_FILENAME=good.avi ID_DEMUXER=avi ID_VIDEO_FORMAT=XVID ID_VIDEO_BITRATE=1033336 ID_VIDEO_WIDTH=624 ID_VIDEO_HEIGHT=352 ID_VIDEO_FPS=23.976 ID_VIDEO_ASPECT=0.0000 ID_AUDIO_FORMAT=85 ID_AUDIO_BITRATE=125776 ID_AUDIO_RATE=0 ID_AUDIO_NCH=0 ID_LENGTH=1255.00 ID_SEEKABLE=1 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4) ========================================================================== ID_VIDEO_CODEC=ffodivx Output of '-identify' on the transcoded 'good' file: Playing good.mp4. libavformat file format detected. ID_VIDEO_ID=0 [lavf] Video stream found, -vid 0 ID_AUDIO_ID=1 [lavf] Audio stream found, -aid 1 VIDEO: [avc1] 1024x768 24bpp 23.976 fps 0.0 kbps ( 0.0 kbyte/s) ID_FILENAME=good.mp4 ID_DEMUXER=lavfpref ID_VIDEO_FORMAT=avc1 ID_VIDEO_BITRATE=0 ID_VIDEO_WIDTH=1024 ID_VIDEO_HEIGHT=768 ID_VIDEO_FPS=23.976 ID_VIDEO_ASPECT=0.0000 ID_AUDIO_FORMAT=255 ID_AUDIO_BITRATE=0 ID_AUDIO_RATE=24000 ID_AUDIO_NCH=2 ID_LENGTH=1255.13 ID_SEEKABLE=1 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264) ========================================================================== ID_VIDEO_CODEC=ffh264 Output of '-identify' on the original 'bad' file: Playing bad.avi. AVI file format detected. ID_VIDEO_ID=0 [aviheader] Video stream found, -vid 0 ID_AUDIO_ID=1 [aviheader] Audio stream found, -aid 1 VIDEO: [XVID] 624x352 24bpp 23.976 fps 1454.3 kbps (177.5 kbyte/s) Clip info: Software: Nandub v1.0rc2 ID_CLIP_INFO_NAME0=Software ID_CLIP_INFO_VALUE0=Nandub v1.0rc2 ID_CLIP_INFO_N=1 ID_FILENAME=bad.avi ID_DEMUXER=avi ID_VIDEO_FORMAT=XVID ID_VIDEO_BITRATE=1454256 ID_VIDEO_WIDTH=624 ID_VIDEO_HEIGHT=352 ID_VIDEO_FPS=23.976 ID_VIDEO_ASPECT=0.0000 ID_AUDIO_FORMAT=85 ID_AUDIO_BITRATE=154368 ID_AUDIO_RATE=0 ID_AUDIO_NCH=0 ID_LENGTH=2848.30 ID_SEEKABLE=1 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4) ========================================================================== ID_VIDEO_CODEC=ffodivx Output of '-identify' on the transcoded 'bad' file: Playing bad.mp4. libavformat file format detected. ID_VIDEO_ID=0 libavformat file format detected. RAWDV file format detected. ID_VIDEO_ID=0 ID_AUDIO_ID=0 VIDEO: [DVSD] 720x480 24bpp 29.970 fps 0.0 kbps ( 0.0 kbyte/s) ID_FILENAME=bad.mp4 ID_DEMUXER=rawdv ID_VIDEO_FORMAT=DVSD ID_VIDEO_BITRATE=0 ID_VIDEO_WIDTH=720 ID_VIDEO_HEIGHT=480 ID_VIDEO_FPS=29.970 ID_VIDEO_ASPECT=0.0000 ID_AUDIO_FORMAT=RADV ID_AUDIO_BITRATE=0 ID_AUDIO_RATE=0 ID_AUDIO_NCH=0 ID_LENGTH=43.41 ID_SEEKABLE=1 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffdv] vfm: ffmpeg (FFmpeg DV decoder) ========================================================================== ID_VIDEO_CODEC=ffdv

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Cannot pass bitrate via command line when using mencoder's profiles
by Markus Bonet 11 Dec '10

11 Dec '10

Hi, I have different profiles for x264 encoding defined. This setup has been working until some updates on my Fedora system were in place. Currently these versions are installed: x264.x86_64 0.0.0-0.28.20100706gitd058f37.fc14 @rpmfusion-free x264-libs.x86_64 0.0.0-0.28.20100706gitd058f37.fc14 @rpmfusion-free mencoder.x86_64 1.0-0.119.20100703svn.fc14 @rpmfusion-free My goal is a 2-pass encoding with a target filesize. My script calculates the target bitrate after the first pass and calls mencoder like this: mencoder input -profile pass2 -x264encopts bitrate=1234 -o output When doing so, x264 fails: x264 [error]: constant rate-factor is incompatible with 2pass. So the bitrate isn't set. If I add bitrate to my profile or call all in the command line without the usage of a profile, everything is ok. Was is broken here and how do I fix it? As mentioned, in my previous setup (on Fedora 12) it was always ok. Thanks Markus PS: This is a copy of a post in doom9.org's forums - just in case anybody wonders. Couldn't get no answers there, hoping for some help here.

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