[Ffmpeg-devel-irc] ffmpeg.log.20130922

burek burek021 at gmail.com
Mon Sep 23 02:05:01 CEST 2013


[00:45] <durka42> so I'm trying to join a series of images (3000 or so) into a video and ffmpeg is only using the first frame
[00:45] <durka42> ffmpeg -f image2 -i frame-%04d.jpg -r 1 video.avi
[00:45] <durka42> am I doing this wrong?
[00:56] <durandal_1707> durka42: you need to set input framerate too
[00:56] <durandal_1707> default one is 25
[00:56] <durka42> durandal_1707: isn't that -r 1?
[00:57] <durandal_1707> that is for output
[00:57] <durka42> oh
[00:57] <durka42> how do I set the input framerate
[00:57] <durandal_1707> just read documentation and save everyone time
[00:57] <durandal_1707> look at image2 documentation
[00:57] <durka42> the example is: ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
[00:58] <durka42> I can't see what I left out
[00:58] <durka42> but if you want to be a dick I'll leave as you asked
[01:03] <durka42> durandal_1707: here's a better link for next time you want to be rude to someone trying to ask for help: https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images
[01:03] <durka42> however
[01:04] <durandal_1707> i'm not a dick
[01:04] <durka42> after setting the input framerate, ffmpeg is still putting the first image for every frame
[01:04] <durka42> my new command is: ffmpeg -f image2 -r 1 -i 'frame-%04d.jpg' -r 1 argh.avi
[01:04] <durka42> I didn't accuse you of being a dick in general
[01:04] <durka42> just this one time
[01:04] <durka42> by rudely pointing me at unhelpful docs I had already read
[01:04] <durandal_1707> have you read fucking image2 demuxer documentation?
[01:06] <durka42> sorry, I'll wait around for someone who is more polite
[01:06] <durka42> thanks for your help
[01:09] <durka42> so when it says in the docs "this demuxer has the following options"
[01:09] <durka42> I'm unclear on how to set one of those
[01:09] <durandal_1707> here is your command:
[01:09] <durka42> does the positioning matter?
[01:09] <durandal_1707> ffmpeg -framerate 1 -pattern_type glob -f image2 -i ~/jpgs/\*.jpg -r 1 -s hd720 /tmp/o.nut
[01:09] <durandal_1707> everything is exlained in documentation
[01:10] <durka42> yeah, I tried adding -framerate 1 and it didn't help
[01:10] <durka42> i'll try your command
[01:11] <klaxa> afterwards, can you just pastebin your command line with the complete output?
[01:12] <durka42> sure
[01:12] <durka42> oh dear, now I get no output video at all, just gray
[01:13] <durka42> klaxa: http://pastebin.com/XdN4btKb
[01:14] <durka42> i'm trying it with a glob pattern instead...
[01:14] <durandal_1707> you sure there are not gaps in frame-XXX?
[01:15] <durandal_1707> but in that case it should report it
[01:16] <durka42> well, there are 3681 so I haven't looked at all the filenames
[01:16] <durka42> there are no gaps in the first 100
[01:16] <durka42> and the 100th frame is different from the first frame
[01:16] <durka42> (but the first 30-50 or so are identical)
[01:17] <klaxa> hmm... i just tried myself, i have a gap between 0003 and 0010
[01:17] <klaxa> no reports, just stops
[01:18] <mark4o> it should stop with -pattern_type sequence, but won't with -pattern_type glob
[01:19] <durandal_1707> the gray thing could be perhaps it try to open all 3681 at once and that is limited..
[01:20] <mark4o> durka42: are you getting a gray video if you play it with ffplay?
[01:20] <durka42> I don't seem to have ffplay
[01:21] <klaxa> also, to get rid of gaps between images i used the following command line in a directory one level deeper than where the images are stored:
[01:21] <klaxa> count=0; for i in $(ls ../*.png); do ln -s "$i" $(printf "%04d.png" "$count"); ((count++)); done
[01:21] <durandal_1707> it shouldn't matter as format is yuvj420p all the time
[01:21] <klaxa> then you can safily use %04d.png as an input parameter
[01:22] <durka42> so I copied the first 100 images into another dir for testing
[01:23] <mark4o> klaxa: the pastebin shows that it went up to frame 3682, so that part is working
[01:23] <klaxa> ah true
[01:23] <durka42> and I'm playing back with VLC
[01:23] <durka42> quicktime refuses to open it
[01:23] <durandal_1707> what vlc version?
[01:24] <durka42> 2.0.8
[01:24] <mark4o> quicktime has trouble with very low framerates like 1fps
[01:25] <durandal_1707> so you could increase output framerate
[01:27] <durka42> oh!
[01:27] <durka42> it changes frames if I add -r 10 before -f image2
[01:30] <durka42> I wanted a frame rate of 1, though...
[01:30] <durka42> I guess I can just duplicate the images more times
[01:30] <durka42> :/
[01:30] <durka42> the lowest frame rate that works is 4
[01:30] <durka42> how strange
[01:31] <durka42> output framerate, I mean
[01:31] <durandal_1707> you want that each image takes 1 second in video?
[01:31] <mark4o> probably a vlc issue
[01:31] <durka42> yeah
[01:31] <wacomcito> hi all..
[01:31] <durka42> should I set -framerate 1/4 maybe?
[01:32] <mark4o> durka42: no, then each frame would take 4 seconds
[01:33] <durka42> but the combination of -framerate 1/4 -r 4 &
[01:33] <wacomcito> i have an archive in FLV format with libx264 codec... i need change format to MP4 but i don't want to recode file again.... (2 hours)
[01:33] <durandal_1707> well if player does not support vfr or 1 fps that is really ....
[01:33] <wacomcito> same codec libx264 an same audio codec.. only change format..
[01:34] <mark4o> wacomcito: ffmpeg -i in.flv -c copy out.mp4
[01:34] <durka42> what does quicktime like anyway
[01:34] <wacomcito> thanks mark4o...
[01:34] <durka42> oh hey, -r 1 works with MOV output!
[01:34] <durka42> well fuck you too, VLC...
[01:36] <mark4o> durka42: try ffplay, you should have it since it comes with ffmpeg
[01:36] <durka42> seems not
[01:36] <durka42> I have ffmpeg installed through homebrew
[01:37] <durka42> oh, homebrew has an extra option for ffplay
[01:37] <durka42> i'll reinstall it
[01:41] <randomguy123> I have a raw h264 file that came from some app. It looks that it's bad, because it doesn't have proper emulation bytes. If I try to use different decoders I get different results. JM reports: "Invalid startcode emulation prevention found.", decoder from android (visualOn based, or whatever they have) produces pure garbage looking picture... FFMPEG produces perfect result. How come?!??
[01:41] <durka42> okay, so the solution was to output to MOV and use quicktime
[01:41] <durka42> i'm off to submit a bug report to VLC
[01:41] <durka42> thanks for your help klaxa, mark4o
[01:42] <randomguy123> I used this command with ffmpeg: ffmpeg -loglevel debug -i incoming_video.h264 incoming_video.y4m
[01:42] <randomguy123> why doesn't it say that file is corrupted, I see no messages whatsorever, as if the file was totally OK.
[01:43] <randomguy123> version is: ffmpeg version N-56277-g2fcef19 built on Sep 14 2013 18:07:53 with gcc 4.7.3
[01:45] <durandal_1707> why would it?
[01:46] <durandal_1707> if you think it should for whatever reason than report it as bug
[01:46] <mark4o> randomguy123: you are complaining about perfect results?
[01:46] <mark4o> can't please everyone I guess
[01:46] <durandal_1707> randomguy123: also you may try with very strict flags
[01:48] <randomguy123> I want to understand why. The file is definitely bad. If I search for 00 00 03 in hex, then 4th byte cannot be anything other than 0, 1, 2 or 3; otherwise file is bad. My h264 file has like 40 such 00 00 03 invalid sequences
[01:49] <randomguy123> soo... I want to know what ffmpeg does to "fix" it. There are different ways: don't drop 03 if it's not followed by 0,1,2 or 3. Or, insert missing 03 after .... I want to find out what I could do to fix it.
[01:49] <randomguy123> how do i enable very strict flags?
[01:52] <durandal_1707> randomguy123: it is in documentation
[01:52] <mark4o> -strict very
[01:52] <durandal_1707> i guess i can rm documentation then
[01:53] <mark4o> just hook up the docs to an irc bot
[01:54] <durandal_1707> :)
[01:56] <randomguy123> tried that strict thing. I got these messages 15 times: [h264 @ 00000000003c8580] no picture
[01:57] <randomguy123> perhaps that means that decoder wasn't able to decode it because it was bad... but, how is that it still produces good yuv output? no artifact etc, all looks good. Output with and without strict is bit exact
[01:58] <randomguy123> is there a normal visual studio based build for ffmpeg, or still it has none?
[01:58] <randomguy123> I'd rather open/build and step through to check what's going on :)
[02:05] <durka42> maybe it is just dropping the bad frames?
[02:05] <durandal_1707> randomguy123: you mean MSVC?
[02:05] <durandal_1707> yes there is, and guess what there is even documentation
[02:05] <randomguy123> yes, msvc.
[02:06] <randomguy123> ffmpeg now has msvc support? (no comd line obviously, msvc isn't just a compiler)
[02:07] <durandal_1707> http://ffmpeg.org/platform.html#toc-Microsoft-Visual-C_002b_002b-or-Intel-C_002b_002b-Compiler-for-Windows
[02:08] <randomguy123> durka42: obviously it drops them, but the rest look good. I wanted to understand what I can do with the file to make it decodable by other codecs. Drop nals that have broken invalid bytes, or fix them manually etc, to achieve the same output as ffmpeg.
[02:09] <durandal_1707> it appears you need someone who understand h264
[02:10] <randomguy123> that c99wrap mamboo jumbo was there for a while. It doesn't build (or clang doesn't build), it crashes then if you build. Builds of c99wrap don't handle something etc. It was far from what I mean: open msvc solution file and build it ;)
[02:11] <durandal_1707> it works for others......
[02:11] <durandal_1707> othwerwise microsoft would not use it
[02:12] <randomguy123> i tried it some time ago, I had to use some version of clang, because with newver it didn't build etc. At the end I was able to build obviously :) it would be better if all these c99wraps came with ffmpeg
[02:12] <durandal_1707> well i think already build one is distributed somewhere....
[02:14] <randomguy123> when I tried to build, there were some new changes that we added to src of c99wrap (or the other tool, whatever its name) and the prebuilt ones were made before that change which is required for some file to compile.
[02:14] <randomguy123> something like htat
[02:15] <randomguy123> anyways, no msvc solution file to open ffmpeg for now. So I'll try to dig through to find out how ffmpeg manages to decode that h264 vide.
[04:37] <highgod> Hi, I want to ask a quesion, I use "ffmpeg -i ./testfile/wwwq.mp4 -vcodec copy  ./testfile/out.h264" command to copy the h264 stream using ffmpeg, but ffmpeg output "Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)", but if I use "ffmpeg -i ./testfile/wwwq.mp4 -vcodec libx264  ./testfile/out.h264" to transcode, ffmpeg run correct, can someone give any
[04:37] <highgod> help? thanks
[04:38] <highgod> I have send mail in the maillist
[04:38] <highgod> Thanks
[04:39] <highgod> I use the windows version, both 32 and 64 bits have the same problems
[04:41] <klaxa> the file testfile/wwwq.mp4 does contain a h264 stream though, right?
[04:41] <klaxa> can you pastebin your command with the complete output?
[04:47] <highgod> the mp4 file can be played correct using vlc
[04:47] <highgod> and ffplay
[04:48] <highgod> but cann't be -vcodec copy correct
[04:51] <klaxa> just because it can be played, doesn't mean it necessarily contains an h264 stream
[04:52] <klaxa> once again, can you pastebin your command with the complete output?
[04:52] <klaxa> a screenshot is fine too if you can't copy paste
[04:52] <highgod> klaxa:OK, I am pasting the output print now
[04:52] <highgod> klaxa, thanks for your reply
[04:52] <klaxa> not in the channel though
[04:53] <klaxa> like... pastebin, if you paste everything in the channel people will kick you
[04:54] <highgod> yeah, my netwrok speed is very low
[04:57] <highgod> klaxa:I paste the output in the mail list, can you check the mail? The title is "Hi, I want ask a quesiton about -vcodec copy, mine doesn't work correct, thanks."
[04:57] <highgod> Thanks
[04:57] <klaxa> sorry i don't follow the mailing list
[04:57] <klaxa> maybe i can find a public copy
[04:58] <klaxa> is it this one? http://ffmpeg.org/pipermail/ffmpeg-user/2013-September/017570.html
[04:58] <klaxa> ah yes looks like it
[04:59] <highgod> klaxa:yes, this mail, thanks
[04:59] <klaxa> might actually be a bug...
[05:00] <highgod> klaxa:can you give me any hint about what's the problem in the mp4 container? because the mp4 is encapsulate by us
[05:01] <klaxa> no idea, you could try to mux it into an mkv container and try to extract it from there, but that might fail too
[05:01] <klaxa> mkv is probably the most sophisticated container in use though
[05:02] <highgod> Yes, I try that too, ffmpeg can't get the stream
[05:02] <highgod> but why it can transcode correct?
[05:02] <klaxa> weird...
[05:02] <highgod> I don't understand
[05:02] <klaxa> can you put it into mkv and play it back?
[05:02] <highgod> Do I have to send the video?
[05:02] <Sashmo> hey everyone, been a while since I asked anything, but does anyone have an example of the black scene detection option that can be used to cut one large file into smaller files?
[05:02] <klaxa> with -vcodec copy? (also the newer and encouraged syntax is -c:v copy)
[05:03] <klaxa> highgod: no, you just run: ffmpeg -i input.mp4 -c copy output.mkv
[05:05] <highgod> klaxa:I try it and it just copy the audio stream, video stream can't either
[05:06] <klaxa> phew tough one... i hope the video doesn't have any sensible data or copyright infringement, people on the mailinglist *might* ask for a sample
[05:09] <highgod> you mean someone will ask for the video for test?
[05:09] <highgod> klaxa
[05:09] <klaxa> yeah maybe
[05:09] <klaxa> like i said i don't follow the mailing list
[05:16] <highgod> klaxa, OK, thanks, no copyright problem
[10:41] <Chais> I'm trying to convert a 1080p video to 720p with ffmpeg with the following options: -map 0:0 -map 0:1 -map 0:2 -map 0:3 -map 0:4 -acodec copy -scodec copy -vf scale=1280:720 -pass 2 -b-pyramid 4 -profile:v high422
[10:41] <Chais> but I keep getting this error message: Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
[10:42] <Chais> I tried setting the framerate by hand, which didn't help. setting the bitrate by hand doesn't seem useful to me, as ffmpeg should be able to determine the required rate more precisely
[10:42] <Chais> any hints?
[10:47] <Chais> the 2-pass options seemed to be the problem. leaving it out will work
[11:04] <smjd> does it work without setting the profile?
[11:35] <Chais> smjd: yes. I'm trying to get a 4.1 file, but always get 3.1
[11:53] <smjd> Chais: I guess you could ask in #x264 too
[12:39] <Chais> how can I specify a target file size?
[13:27] <smjd> I don't know if -bufsize could be set high enough to work as a target file size
[13:28] <smjd> nevermind
[14:18] <drwx> what is the default algorithm used by the scale filter?
[15:48] <superware> can I play a video-only RTP channel over UDP without an SDP file? something like ffplay -f h264 rtp://0.0.0.0:1234 ?
[15:51] <vl4kn0> Hi, I've got video that does not have pts information for video, it always gives me the  AV_NOPTS_VALUE. Is there any way I could synchronise this?
[16:15] <utente> hello. i have cubieboard that use a ALLWINNER A10 (Soc arm). OS is debian 7 for armhf. Video reproduction in not the bes, they suggest me to recompile ffmpeg activating support to NEON. Somehoe can succest me how to do?
[16:17] <utente> not the best*
[16:18] <spaam> did you try --enable-neon ?
[16:24] <utente> spaam, neved recompiled ffmeg before now, so i came here to colect info before to try to do.
[16:24] <utente> spaam, it is enoug that parameter? --enable-neon during compilation?
[16:25] <utente> it is possible to check what option is already activated in ffmneg?
[17:04] <gp> Can ffmpeg decode a "copy-once" encrypted wtv file on the computer that recorded it?
[17:20] <aktau> Hey guys
[17:20] <aktau> I'm checking if my videos are interlaced with ffmpeg -vf idet
[17:20] <aktau> Which works great
[17:20] <aktau> But some files are ridiculously long
[17:20] <aktau> I'd like to analyze the first 1000 frames or some such
[17:20] <aktau> But can't find the right flag/incantation for it
[17:21] <aktau> Perhaps someone knows this by heart
[17:21] <aktau> ?
[17:23] <gp> aktau: http://www.ffmpeg.org/ffmpeg.html#Video-Options
[17:23] <gp> -frames:v
[17:23] <aktau> That, is awesome, sorry I didn't find it by myself gp, my google-fu was weak :(
[17:24] <aktau> Thanks for the tip
[17:24] <gp> no problem
[17:25] <aktau> I'm so exited, this really works wonders, and I can do it all offline on some headless server. I'd like to formally thank the ffmpeg community for making a top-notch tool
[17:25] <gp> Probably want to use -ss and check in a few different places in the video
[17:28] <aktau> Yea, you're right
[17:28] <aktau> Luckily I don't need it to be 100% accurate at the moment though
[17:28] <aktau> I suspect people will tell me if the films shows a lot of "crazy bars"
[17:29] <aktau> Thing is I'm displaying with vaapi-mplayer, which precludes using yadif autodetection
[17:29] <aktau> Because making a copy to normal RAM just trashes all the gains that vaapi so painstakingly brought
[17:30] <aktau> Well, at any rate, VAAPI deinterlacing is still really really experimental
[17:30] <aktau> Only xmbc has it mainlined, and mpv is in the process of doing so
[17:30] <aktau> And it's only a bob deinterlacer (ugh...)
[17:30] <gp> =/
[17:30] <aktau> Temporal/spatial is only supported on haswell, though they said they would bring it to older HW as well
[17:32] <aktau> I'd really really like temporal/spatial, but for now bob will have to do, because the barring is horrible for some vids atm
[19:11] <viric> hm anyone knows, how can I play with ffplay only one field of the interlaced video?
[19:11] <viric> does x264 share information between fields?
[19:13] <viric> -vf field=0
[20:55] <threexk> hello.  I'm trying to start and stop ffmpeg recording from Python.  If I send SIGINT or SIGTERM to ffmpeg it stops what it was doing but does not fully exit.  Does anyone have an idea why?
[20:56] <threexk> (This may be more a Python question, not sure.)
[20:57] <threexk> s/recording/encoding/
[21:01] <utente> hello, i recompiled ffmeg with --enabled-mono (i followed howto here https://trac.ffmpeg.org/wiki/UbuntuCompilationGuide#ffmpeg). Now i gave binary fmmpeg in /root/bin/ffmpeg  and in /root/bin there are also other eecutable. How to make gmplayer and totem to take afvantage of them? have I co comy these executable in /bin ?
[21:07] <threexk> nevermind my question.  Apparently I needed to close my pipe to stdin prior to sending SIGTERM.
[00:00] --- Mon Sep 23 2013


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