March 2008 - MEncoder-users - lists.mplayerhq.hu

"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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encode to h264 (flash support)
by Ing. Branislav Gerzo 03 Mar '08

03 Mar '08

Hello all, after recent flash player update http://www.adobe.com/devnet/flashplayer/articles/hd_video_flash_player.html http://labs.adobe.com/wiki/index.php/Flash_Player:9:Update:H.264 I am trying using mencoder to encode video to h264 and audio to aac. Firt, I am working with video, so I want make be sure, audio is not problem. I am using this command: mencoder amy1.flv -oac mp3lame -srate 44100 -lameopts \ vbr=2:q=8:aq=0:mode=1:lowpassfreq=16000 -ovc x264 -x264encopts \ threads=auto:subq=5:partitions=4x4:8x8dct:frameref=3:me=hex:bframes=4:b_pyramid:psnr:bitrate=348\ -of lavf -lavfopts format=mov -o amy1.mp4 I am doing certainly something wrong. I downloaded youtube mp4 and analyze it a little bit, here are main differencies between my and youtube mp4, which plays in flash: YOUTUBE mp4: Playing video.mp4. ISO: File Type Major Brand: ISO/IEC 14496-1 (MPEG-4 system) v2 Quicktime/MOV file format detected. ID_AUDIO_ID=0 [mov] Audio stream found, -aid 0 ID_VIDEO_ID=1 [mov] Video stream found, -vid 1 VIDEO: [avc1] 320x240 24bpp 15.000 fps 0.0 kbps ( 0.0 kbyte/s) ID_FILENAME=video.mp4 ID_DEMUXER=mov ID_VIDEO_FORMAT=avc1 ID_VIDEO_BITRATE=0 ID_VIDEO_WIDTH=320 ID_VIDEO_HEIGHT=240 ID_VIDEO_FPS=15.000 ID_VIDEO_ASPECT=0.0000 ID_AUDIO_FORMAT=mp4a ID_AUDIO_BITRATE=99896 ID_AUDIO_RATE=44100 ID_AUDIO_NCH=2 ID_LENGTH=75.33 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264) ========================================================================== ID_VIDEO_CODEC=ffh264 ========================================================================== Opening audio decoder: [faad] AAC (MPEG2/4 Advanced Audio Coding) AUDIO: 44100 Hz, 2 ch, s16le, 99.9 kbit/7.08% (ratio: 12487->176400) ID_AUDIO_BITRATE=99896 ID_AUDIO_RATE=44100 ID_AUDIO_NCH=2 Selected audio codec: [faad] afm: faad (FAAD AAC (MPEG-2/MPEG-4 Audio) decoder) ========================================================================== AO: [dsound] 44100Hz 2ch s16le (2 bytes per sample) ID_AUDIO_CODEC=faad Starting playback... =============================================================================== ISO: File Type Major Brand: Original QuickTime Quicktime/MOV file format detected. ID_VIDEO_ID=0 [mov] Video stream found, -vid 0 ID_AUDIO_ID=1 [mov] Audio stream found, -aid 1 VIDEO: [avc1] 512x384 24bpp 29.970 fps 0.0 kbps ( 0.0 kbyte/s) ID_FILENAME=amy1.mp4 ID_DEMUXER=mov ID_VIDEO_FORMAT=avc1 ID_VIDEO_BITRATE=0 ID_VIDEO_WIDTH=512 ID_VIDEO_HEIGHT=384 ID_VIDEO_FPS=29.970 ID_VIDEO_ASPECT=0.0000 ID_AUDIO_FORMAT=.mp3 ID_AUDIO_BITRATE=0 ID_AUDIO_RATE=44100 ID_AUDIO_NCH=2 ID_LENGTH=115.55 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264) ========================================================================== ID_VIDEO_CODEC=ffh264 ========================================================================== Opening audio decoder: [mp3lib] MPEG layer-2, layer-3 AUDIO: 44100 Hz, 2 ch, s16le, 40.0 kbit/2.83% (ratio: 5000->176400) ID_AUDIO_BITRATE=40000 ID_AUDIO_RATE=44100 ID_AUDIO_NCH=2 Selected audio codec: [mp3] afm: mp3lib (mp3lib MPEG layer-2, layer-3) ========================================================================== AO: [dsound] 44100Hz 2ch s16le (2 bytes per sample) ID_AUDIO_CODEC=mp3 Starting playback... from my point problem is with different ISO, but I don't know how to put h264 in mov cointainter properly. Any hint please ? Thank you very much /Brano

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Encoding from multiple input image files
by Gilles Pelletier 03 Mar '08

03 Mar '08

I am trying to encode a bunch of jpg files using the following command: mencoder mf://*.jpg -mf w=800:h=600:fps=25:type=jpg -ovc lavc -lavcopts vcodec=mpeg4:mbd=2:trell -oac copy -o output.avi I got this command from here: http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-enc-images.html I get the following results: $ mencoder mf://*.jpg -mf w=800:h=600:fps=25:type=jpg -ovc lavc -lavcopts vcodec=mpeg4:mbd=2:trell -oac copy -o output.avi MEncoder 1.0rc1-4.1.2 (C) 2000-2006 MPlayer Team CPU: Intel(R) Pentium(R) 4 CPU 3.00GHz (Family: 15, Model: 3, Stepping: 4) CPUflags: Type: 15 MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1 Compiled with runtime CPU detection. success: format: 16 data: 0x0 - 0x0 MF file format detected. [mf] search expr: *.jpg [mf] number of files: 262 (1048) VIDEO: [IJPG] 800x600 24bpp 25.000 fps 0.0 kbps ( 0.0 kbyte/s) [V] filefmt:16 fourcc:0x47504A49 size:800x600 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: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffmjpeg] vfm: ffmpeg (FFmpeg MJPEG decoder) ========================================================================== VDec: vo config request - 3264 x 2448 (preferred colorspace: Planar 422P) Could not find matching colorspace - retrying with -vf scale... Opening video filter: [scale] VDec: using Planar 422P as output csp (no 1) Movie-Aspect is undefined - no prescaling applied. SwScaler: reducing / aligning filtersize 1 -> 4 SwScaler: reducing / aligning filtersize 1 -> 4 SwScaler: reducing / aligning filtersize 1 -> 1 SwScaler: reducing / aligning filtersize 9 -> 8 SwScaler: BICUBIC scaler, from yuv422p to yuv420p using MMX2 SwScaler: using 4-tap MMX scaler for horizontal luminance scaling SwScaler: using 4-tap MMX scaler for horizontal chrominance scaling SwScaler: using 1-tap MMX "scaler" for vertical scaling (YV12 like) SwScaler: 3264x2448 -> 3264x2448 videocodec: libavcodec (3264x2448 fourcc=34504d46 [FMP4]) [VE_LAVC] High quality encoding selected (non-realtime)! Segmentation fault I've been following this mailing list for a month or so but this is the first time I really try out mencoder, so I don't really know what is going on. Can you help me? -- Gilles

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Progressive Scan DVD player?
by Andy Civil 03 Mar '08

03 Mar '08

I apologise for the slight off-topic nature of this, but I think the skill set of the friends here is appropriate: I'm trying to get the best out of my Progressive Scan DVD player (it's actually a DVP3140). I've tried using tfields=2,scale=720:480,harddup to make a 60000/1001 divx stream, but my player ignores it - I'm assuming that it can't actually decode a 720p60fps stream, but requires a 720i30fps stream to work. The thing is, if I let the DVD player upconvert this to 60fps in progressive scan mode, that's no different from letting the TV (an LCD display) do it, is it? If I can't actually play a full frame (720) at 60fps, then I'm not going to get any better quality than a regular DVD. Without expecting anyone to know my specific player, has anyone discovered the best kind of stream to use with MEncoder for DivX capable players in general? Also, has anyone experimented with better-quality players that are not necessarily HD-DVD or BLU-RAY but can accept superior streams written to DVDs (maybe without the ~10,000kb/s data rate restriction)? Thanks -- Andy

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Mencoder - Blocky Artifacts - very first couple of frames only and only from DVD
by Nigel Arnold 02 Mar '08

02 Mar '08

Hello When i use mencoder (any SVN or RC), i get the exact same problem (only from DVD's) (Win32) For the very first few frames of the encoded video, i see large blocky artifacts. just for a split second and then there gone. I've stripped my command line right down to bare minimum and they are still present Interestingly enough, if i use x264encopts and x264 = still blocky xvidencopts and xvid = still blocky lavc vcodec=mpeg4 - still blocky But if I encode from a file, its crystal clear as it should be, so it looks to be DVD related. My 'stripped' command line looks like this :- mencoder dvd://1 -dvd-device "R:\" -of lavf -lavfopts format=avi ?oac copy ?ovc lavc ?lavcopts vcodec=mpeg4:mbd=1:vbitrate=1800 -o c:\new.avi -chapter 02-02 -endpos 00:00:10 Example of what i mean in terms of video blocks http://img87.imageshack.us/img87/1015/image1sh5.jpg This is very nearly the same corruption everytime for a DVD that starts with a black screen (99% do) When I start at a chapter, I get something like this http://img341.imageshack.us/img341/9736/image2iz5.jpg again only for about 0.5 seconds and then the video is fine. ANY help much appreciated. Regards N

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Re: [MEncoder-users] anamorphic quicktime .mov detected with wrong aspect ratio
by Bram 01 Mar '08

01 Mar '08

Bram wrote: > 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 > In reply to Cooleyr (I've turned of digest mails now, it's too inconvenient): Thanks for the -demuxer mov tip, but it doesn't change anything sadly. The movie is still shown with the 4:3 aspect ratio. Any more tips what could be wrong? I'm guessing it fails to see an (undocumented, perhaps) aspect ratio flag, as the pixel aspect ratio is given as 0:1 0:1. Best regards, Bram

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