May 2005 - ffmpeg-user - lists.ffmpeg.org

ffmpeg CBR transcode
by patil.vishwanath＠gmail.com 20 May '05

20 May '05

I am trying to convert a file stored on a dvd to mpeg2ts format using ffmpeg. I am looking out for a file that has constant bit rate of 4Mbps. Now i have been successful in transcoding the content, but how do i confirm that it is CBR, and it is 4Mbps. this is the command that i used to transcode using ffmpeg ... ./ffmpeg -i /mnt/cdrom/VIDEO_TS/VTS_02_1.VOB -v mpegts -b 3072 -s 4cif -map 0:0 -map 0:3 /home/work/media/snatch_test.ts ffmpeg version 0.4.9-pre1, build 4731, Copyright (c) 2000-2004 Fabrice Bellard configuration: --enable-gpl --enable-a52 --enable--faad --enable-faac --prefix=/home/work/vlc/ffmpeg-20041113 built on May 20 2005 11:11:11, gcc: 3.3.3 20040412 (Red Hat Linux 3.3.3-7) Input #0, mpeg, from '/mnt/cdrom/VIDEO_TS/VTS_02_1.VOB': Duration: 00:36:54.5, start: 0.233567, bitrate: 3878 kb/s Stream #0.0: Video: mpeg2video, 720x480, 29.97 fps Stream #0.1: Audio: ac3, 48000 Hz, 5:1, 448 kb/s Stream #0.2: Audio: ac3, 48000 Hz, 5:1, 448 kb/s Stream #0.3: Audio: ac3, 48000 Hz, stereo, 192 kb/s Stream #0.4: Audio: ac3, 48000 Hz, stereo, 192 kb/s Stream mapping: Stream #0.0 -> #0.0 Stream #0.3 -> #0.1 Press [q] to stop encoding frame= 635 q=0.0 Lsize= 8518kB time=21.0 bitrate=3319.2kbits/s video:8046kB audio:164kB global headers:0kB muxing overhead 3.753051% this the output i get when i play it using ffplay.... ./ffplay /home/work/media/snatch_test1.ts -stats Input #0, mpegts, from '/home/work/media/snatch_test1.ts': Duration: 00:18:10.3, start: 0.000000, bitrate: 64 kb/s Stream #0.0[0x100]: Video: mpeg2video, 704x576, 29.97 fps Stream #0.1[0x101]: Audio: mp2, 48000 Hz, stereo, 64 kb/s Now, i want to know some things that i understand from the extract.... please correct me if i am wrong... number of frames encoded by ffmpeg = 635 video captured size 8046 KB audio captured size 164 KB time is 21 seconds what is bitrate 3319.2kbits/s and 3878kbits/s mentioned.... and what happened to 3072 that i specified in the command..... are there any sw tools to find out what is the bitrate of a stream that is coming from a mpeg2ts streamer..... how does the ffplay find out the file is mpeg2ts and pid's of the audio and video in the mpeg2ts file -- From, Vishwanath.A.Patil R&D Measurements and Controls India Ltd. Electronic City Bangalore 560100

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libavcodec/libavformat thread safe?
by steuer＠unixsystems.de 20 May '05

20 May '05

hello everybody, are the two ffmpeg libraries libavformat and libavcodev thread safe? I tried to start coding and was wondering that calls to av_find_stream_info() broke the threaded application. is there a way to savely use ffmepg in threaded apps? regards, heri -- This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden.

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AVI to 3gp audio sync issue.
by mediastream＠gmail.com 19 May '05

19 May '05

Gents, I've been at this for 2-3 months already... I've got following dilemma - WIN XP box, ffmpeg 0.4.9-pre1; input files: AVI - XVID 702x480 29.97 1500kbps with 1ch 44.1 16bit pcm/ and various WMV v.7/v.8/v.9 --- all need to be converted to 3gp for 1 phone model. First mencoder converts these to libavc mp4 and scales it to 176x144, preprocessing it fo ffmpeg so to say. Then ffmpeg encodess it to 3gp like so: ffmpeg -async 100 -i 176_libav_pcm.avi -bitexact -vcodec mpeg4 -s qcif -b 50 -r 8 -acodec amr_nb -ac 1 -ar 8000 -ab 12 -nr -hq -preme -qmin=3 -pass 1 async100_12_8fps.3gp As you can see I tried multiple async values, fps and a/v brate. I noticed that different -ab / -r shift audio track differently, almost none of them hit the spot. It's only .2 - .3 second behind, but it does get annoying. It seems that delay is constant across 5 min files. I tried -itsoffset -0:00:00.xx and of course it works but it seems to vary from file to file.. So, is there a way to convert xvid/wmv to 3gp without loosing audio sync? there's really no explanation of -async function anywhere.. has anyone links to some more detailed docs regaqrding it? Any help is appreciated guys. Thanks. Dennis.

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ffmpeg for IP Webcam
by ludovic.pinon＠esstin.uhp-nancy.fr 19 May '05

19 May '05

Hello everyone, First, please excuse my mail, but I don't speak English very well... But, I need to capture video from IP Webcam (mjpeg format), and, I tried to use ffmpeg librairies, but failed... The main problem, I think, is that I don't exactly know what to use: ffserver, ffmpeg or ffplay. I tried to use ffplay with the following syntax : ffplay http://webcam5.hrz.tu-darmstadt.de/mjpg/video.mjpg (a website where I could have found video streaming), but, even if it open it in a window, the video can't be seen. After, I tried with ffserver and ffmpeg, and had two problems : I don't know the good configuration of ffserver.conf (don't even know if I need to use ffserver), and I have got an error when executing ffmpeg: "couldn't find video grab device". Please answer me, Regards, Ludovic.

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convert list of images to mpeg
by johannes.behr＠igd.fhg.de 18 May '05

18 May '05

Hi, i'm new to ffmpeg and have a very simple problem (checked the FAQ already) I try to encode a mpeg file from a list of images. The frames are PNG-files and named as followed: frame0001.png, frame0001, ... frame2000.png As fare as I understand the man-pages correctly the following line should produce a mpeg file: ---------------------------------------- ffmpeg -i vh%04d.png /tmp/a.mpg ---------------------------------------- But all I get is the following error message: ---------------------------------------- ffmpeg version 0.4.9-pre1, build 4738, Copyright (c) 2000-2004 Fabrice Bellard configuration: --build i386-linux --enable-gpl --enable-pp --enable-zlib --enable-vorbis --enable-a52 --enable-dts --disable-mmx --disable-debug --prefix=/usr built on Feb 5 2005 01:20:01, gcc: 3.3.5 (Debian 1:3.3.5-6ubuntu1) Input #0, image2, from 'vh%04d.png': Duration: 00:01:58.0, start: 0.000000, bitrate: N/A Stream #0.0: Video: png, 300x300, 25.00 fps Output #0, mpeg, to '/tmp/a.mpg': Stream #0.0: Video: mpeg1video, 300x300, 25.00 fps, q=2-31, 200 kb/s Stream mapping: Stream #0.0 -> #0.0 [mpeg1video @ 0x82d0e1c]only YUV420 is supported Error while opening codec for stream #0.0 - maybe incorrect parameters such as bit_rate, rate, width or height ---------------------------------------- The problem seams to be the 'only YUV420 is supported' part. I tried jpg-fiels (like in the man pages) with the same result. Any Hint? Regards, johannes PS: Using Linux/Ubuntu version of ffmpeg.

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About target presets
by penny_it＠hotmail.com 18 May '05

18 May '05

Since in our project (Lulop2) SVCD is far too low quality, could it be possible to add a preset for very high quality material? I?m looking for something with DVD quality MPEG, but not AC3-audio. Audio should be high quality too, but preferably MPEG since it shouldn?t be necessary for users to install additional codecs. I already took a quick look on the source and noticed, that it shouldn?t be very hard to implement... Many thanks _________________________________________________________________ Don't just search. Find. Check out the new MSN Search! http://search.msn.click-url.com/go/onm00200636ave/direct/01/

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[Ffmpeg-user-old] streaming to Real(Helix)Server
by vato＠wnet.ua 18 May '05

18 May '05

Hi! Is anybody succeeded streaming with ffmpeg to Real(Helix)Server? Is here an option to ffmpeg to put passwords and creating SDP? -- Viktor Kompaneyets Wnet project manager ------------------------------------------------------- This SF.Net email is sponsored by Oracle Space Sweepstakes Want to be the first software developer in space? Enter now for the Oracle Space Sweepstakes! http://ads.osdn.com/?ad_id=7412&alloc_id=16344&op=click _______________________________________________ Ffmpeg-user mailing list Ffmpeg-user at lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/ffmpeg-user

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Video edition with ffmpeg
by georges.legoualher＠etiam.com 18 May '05

18 May '05

Hi, Is there a way to extract a subsequence from a video file using ffmpeg? For example, to extract 10 secs of a video file, starting at time 00:00:15 ? Many thanks, Georges -- Responsable Projet/Project Manager __________________________________________ www.etiam.com ETIAM "Multimedia Connectivity for Healthcare" Technopole Atalante - Villejean 35000 Rennes FRANCE Tel: +33 2 99 14 33 88 Fax: +33 2 99 14 33 80

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Problems streaming files
by ivoras＠yahoo.com 18 May '05

18 May '05

Hi! First problem is, when I try to stream an AVI file with ffserver, and put this in the ffserver.conf: <Stream mystream.avi> Format avi File "/storage/myvideo.avi" </Stream> <Stream mystream2.avi> Format rtp File "/storage/myvideo.avi" </Stream> The first one works - I can use any http-aware client to acces the file, but the second doesn't. When I try to view it with RealPlayer 10, I get these lines in my log: 127.0.0.1 - - [Tue May 17 16:35:49 2005] "GET /mystream2.rtsp HTTP/1.1" 200 107 127.0.0.1 - - [Tue May 17 16:35:50 2005] "SETUP rtsp://localhost:5454/streamid=0 RTSP/1.0" 200 564 127.0.0.1 - - [Tue May 17 16:35:50 2005] "SETUP rtsp://localhost:5454/streamid=0 RTSP/1.0" 200 564 But, RealPlayer complains: "Requested file not found. The link you followed may be outdated or inaccurate. (rtsp://localhost:5454/mystream2.avi)" I verified that ffserver listens to port *:5454, and there's no firewall involved. Second problem, I need to stream some RealAudio files, so I did this: <Stream uticnica.ra> Format ra File "/home/kzimmer/real/Content/OR/JavaUticnice/Audio/1.ra" NoVideo </Stream> Now ffserver doesn't want to start: "/usr/local/etc/ffserver.conf:163: Unknown Format: ra Incorrect config file - exiting." I actually need the RealAudio files served via RTSP, but when I set "Format rtp", this error happens: [NULL @ 0x282ff4f0]Unsupported video codec ...and the server starts, but the stream is not visible in /stat.html All this is ffmpeg/ffserver 0.4.9-pre1 on FreeBSD. __________________________________ Do you Yahoo!? Make Yahoo! your home page http://www.yahoo.com/r/hs

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encoding an xdiv avi to many svcd's
by davidmarceau＠sympatico.ca 18 May '05

18 May '05

Hi there, I have encoded successfully a small xdiv avi into vcd/svcd-ready mpg files: ffmpeg -hq -i xdivmovie.avi -target svcd ./mpegmovie.mpg ffmpeg -hq -i xdivmovie.avi -target vcd ./mpegmovie.mpg PROBLEM: That said problems arose when I attempted to encode a large xdiv avi into multiple vcd/svcd-ready mpg files. Using ffmpeg to split xdiv avi into three parts, the second and third parts when played gave video and audio are out of sync. Here is what I tried: 1)hand-carved the input avi into three different parts. ffmpeg -hq -ss 00:00:00 -t 00:45:00 -i xdivmovie.avi -target svcd ./mpegmovie1.mpg ffmpeg -hq -ss 00:45:00 -t 00:45:00 -i xdivmovie.avi -target svcd ./mpegmovie2.mpg ffmpeg -hq -ss 01:30:00 -t 00:23:22 -i xdivmovie.avi -target svcd ./mpegmovie3.mpg Why is ffmpeg giving me video/audio sync problems when I encode only parts of the xdiv avi? ANYWAYS SOLUTION: The following strategy works with no video/audio sync problems. What mpgtx does differently? I don't know but it works for me :) ffmpeg -hq -i xdivmovie.avi -target svcd ./mpegmovie.mpg mpgtx -s mpegmovie.mpg [-00:45:00] -b mpegmoviepart1 mpgtx -s mpegmovie.mpg [00:45:00-01:30:00] -b mpegmoviepart2 mpgtx -s mpegmovie.mpg [00:01:30-] -b mpegmoviepart3 From there using a tool like k3b works to burn using these mepgmoviepart files. The aspect ratio is not ok but if the svcd is in the computer I know if I change the aspect ration to anamorphic, it fixes itself. I hope this helps. Cheers, David Marceau

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