[Ffmpeg-devel-irc] ffmpeg.log.20160524

[burek]

[02:17:42 CEST] <Mista_D> Is there a way to detect duplicate video frames without ImageMagick?
[02:50:30 CEST] <throckmorton> I am trying to add jpeg 2000 still image support to VLC
[02:51:09 CEST] <throckmorton> when I try to open a file, I get get_buffer failed error from avcodec
[02:51:59 CEST] <throckmorton> [jpeg2000 @ XXXXX] get_buffer() failed
[02:52:16 CEST] <throckmorton> what is the best way of troubleshooting this ?
[03:00:06 CEST] <spooooon> I'm not an expert, but can you breakpoint and see the callstack
[03:00:12 CEST] <spooooon> or grep ffmpeg for the failure string
[04:04:21 CEST] <yagiza> Hello!
[04:46:23 CEST] <gxm1221> ffmpeg is awesome!!
[04:46:25 CEST] <gxm1221> really like it :)
[09:13:28 CEST] <YellowOnion> Could someone help me with an error, I just finished compiling ffmpeg on windows with opencl support -opencl_bench works, but unsharp is giving me an error (which I'll paste shortly)
[09:16:40 CEST] <YellowOnion> http://pastebin.com/At4YnFEb
[09:23:36 CEST] <YellowOnion> actually never mind figured it out.
[10:24:42 CEST] <YellowOnion> is unsharp broken for anything larger than a 7 matrix? the contrast goes out the window, you get strange banding.
[10:37:54 CEST] <YellowOnion> And if your matrix is really high, you actually get the opposite of sharpening for positive values. ha, and if you use a png as a target the picture goes completely haywire.
[11:09:57 CEST] <Pisa_Dev> Hi All. I need to install ffmpeg in a Phi Server without root permission, so i cannot use apt. I need all the dependences, like lib264, for install FFMpeg. Is there any possibility to download all dep and install it? I followed a Guide in FFMpeg site, but most of the packages are not avaiable.
[11:32:36 CEST] <YellowOnion> Pisa_Dev, you're probably better off downloading the .deb's manually and extracting them
[11:37:14 CEST] <Pisa_Dev> Hi YellowOnion! Thanks for the reply
[11:37:31 CEST] <Pisa_Dev> i'm in a Red Hat
[11:38:03 CEST] <Pisa_Dev> yum don't work properly nor apt source
[11:38:36 CEST] <YellowOnion> can you do it on another machine and push the files there?
[12:05:22 CEST] <yagiza> Do anyone know anything about resampling delay?
[12:06:12 CEST] <YellowOnion> yagiza, vaguely, why is that?
[12:07:01 CEST] <yagiza> YellowOnion, ???
[12:07:59 CEST] <yagiza> YellowOnion, I just want to know, what do I have to do with it?
[12:11:12 CEST] <YellowOnion> yagiza, Well that kinda depends on what you're doing in the first place.
[12:11:30 CEST] <yagiza> YellowOnion, I'm encoding audio.
[12:12:35 CEST] <YellowOnion> just audio? no video? samplerates? what resampler are you using?
[12:12:39 CEST] <yagiza> YellowOnion, and I need to resample audio samples I'm getting from audio device to format, supported by audio codec.
[12:12:52 CEST] <yagiza> YellowOnion, swr
[12:16:27 CEST] <YellowOnion> yagiza, unless I'm misunderstanding the situation, delay from resampling isn't going to be your primary issue with delay when you're using an audio codec.
[12:17:33 CEST] <yagiza> YellowOnion, I don't have any issues with delay at all so far.
[12:18:11 CEST] <yagiza> YellowOnion, but I just wanna know if I have to take that delay into account during encoding.
[12:18:25 CEST] <YellowOnion> plus I'm not sure what the delay is compared to? if its just audio then who cares?
[12:19:42 CEST] <yagiza> YellowOnion, right now I just add it to number of processed samples when calculating audio frame PTS.
[12:20:09 CEST] <yagiza> YellowOnion, but I'm not sure if that's what I should do.
[12:22:20 CEST] <YellowOnion> Are you worried about track desync?
[12:23:55 CEST] <yagiza> YellowOnion, yes
[12:27:27 CEST] <YellowOnion> I would assume ffmpeg handles this itself, assuming the sources are in sync to begin with.
[12:44:45 CEST] <YellowOnion> yagiza, though if your sample rate is very low (like 8k) you might end up with smearing of of the transients which is caused by the group the group delay :P
[12:51:08 CEST] <wallbroken> hor to rotate a video of 90 degrees?
[13:12:23 CEST] <Mrc_munir> Hello i have some problem linker -fPIC with clang compiler for x86_64 in android platform but we use --enable-pic how fix i.e libswscale.a(rgb2rgb.o): requires dynamic R_X86_64_PC32 reloc against 'ff_w1111' which may overflow at runtime; recompile with -fPIC?
[14:19:23 CEST] <Hababam> hi
[14:19:57 CEST] <Hababam> does any of your guys have experience with rstp input to ffmpeg ?
[14:20:05 CEST] <Hababam> i get allot of missing rtp packets
[14:20:11 CEST] <Hababam> but in vlc
[14:20:15 CEST] <Hababam> the stream shows nicely
[14:48:06 CEST] <farfel> hello - question about jpeg 2000 support in ffmpeg. I see there is a native decoder and optional openjpeg decoder
[14:48:54 CEST] <farfel> I have built ffmpeg with openjpeg enabled. I have another project which uses avcodec
[14:49:18 CEST] <farfel> ffmpeg decodes j2k files using openjpeg, but the other project uses the native decoder
[14:49:46 CEST] <farfel> so, with two decoders, how does an avcodec user choose which one to use ?
[14:50:12 CEST] <farfel> other project is videolan
[14:50:42 CEST] <farfel> both projects use the same libavcodec library
[14:51:04 CEST] <farfel> i.e. ffmpeg and videolan use the same libavcodec library
[14:51:42 CEST] <JEEB> videolan is a group of people and projects under an umbrella
[14:51:49 CEST] <farfel> vlc project
[14:52:20 CEST] <farfel> I want to add j2k support to vlc for still images, via avcodec
[14:52:38 CEST] <farfel> and openjpeg seems to support more kinds of j2k images
[14:53:02 CEST] <wallbroken> hor to rotate a video of 90 degrees?
[14:53:06 CEST] <JEEB> there's a way to force a decoder, but unfortunately I don't remember how to use that API
[14:53:19 CEST] <farfel> ok, thanks anyways
[14:53:46 CEST] <c_14> wallbroken: https://ffmpeg.org/ffmpeg-filters.html#transpose
[14:53:55 CEST] <farfel> JEEB: so, if I don'
[14:54:04 CEST] <farfel> t force, it will default to native ?
[14:54:26 CEST] <farfel> both avcodec and openjpeg are built as shared libraries, if this makes a difference
[14:54:38 CEST] <farfel> I thought maybe vlc wasn't loading openjpeg, since it was shared
[14:55:42 CEST] <farfel> is this an appropriate question for ffmpeg-devel ?
[15:41:42 CEST] <odinsbane> I encoded a video using ffmpeg, but I cannot play it back using quicktime. VLC works, I'm wondering if you have any suggestions. Also I need to use the h.264 encoding.
[15:41:46 CEST] <odinsbane> ffmpeg -i "out%03d.png" -c:v libx264 -qp 0 lf200-low-res.mp4
[15:44:06 CEST] <DHE> just off the top of my head, try a higher qp value like 15? 0 is codec-lossless mode
[15:54:51 CEST] <odinsbane> No matter which way I do it, quicktime won't play the videos. The best part is when it sends me to a webpage explaining how great quicktime is for playing all sorts of videos.
[15:55:19 CEST] <relaxed> odinsbane: add -pix_fmt yuv420p
[15:55:19 CEST] <JEEB> quantizer zero won't work
[15:55:26 CEST] <JEEB> it's lossless
[15:55:29 CEST] <JEEB> as was mentioned
[15:55:44 CEST] <JEEB> otherwise see the output pixel format in the ffmpeg cli logs and force it in case it is not yuv420p
[15:55:56 CEST] <odinsbane> I tried specifing it with a different value, I also tried omitting it.
[15:56:13 CEST] <odinsbane> (qp value that is. I am trying the px value now.)
[15:56:23 CEST] <JEEB> don't change it if it's already yuv420p
[15:56:27 CEST] <JEEB> see your damn logs
[15:56:41 CEST] <JEEB> aka "don't throw things in without reason"
[15:57:00 CEST] <JEEB> and if you can't parse your logs, post them on a pastebin or gist
[15:59:01 CEST] <DHE> if you use "-profile:v main" would it reject non-4:2:0p content?
[16:05:24 CEST] <odinsbane> It was defaulting to yuv444p, If I specify yuv440p and set the qp value to 15 it is playable. I am supposed to use lossless compression though. Why doesn't qp 0 work?
[16:05:50 CEST] <odinsbane> er 420p
[16:11:26 CEST] <furq> odinsbane: does -qp work with yuv420p
[16:11:31 CEST] <DHE> different decoder profiles are required. 420p is broadcast standard, 444 requires the decoder to be more "sophisticated" to work
[16:11:33 CEST] <furq> -qp 0, that is
[16:11:56 CEST] <DHE> yes, but it's not true lossless. 4:4:4 -> 4:2:0 degrades the image quality even before H.264 gets it
[16:12:03 CEST] <furq> yeah what he said
[16:12:21 CEST] <odinsbane> I swear the person giving these specs is making some sort of joke. Thanks for the help. For some odd reason yuv420p with crf 0 works. yuv420p and qp 0 does not work.
[16:12:33 CEST] <kepstin> -qp 0 works with yuv420p, but the lossless mode isn't supported by the normal 'high' profile.
[16:13:26 CEST] <kepstin> so a high profile only decoder can't handle it, only a high444pp decoder can iirc. even at 4:2:0 sampling.
[16:13:59 CEST] <odinsbane> scratch that.
[16:14:41 CEST] <odinsbane> I cannot get qp 0 or crf 0 to produce a video that quicktime will play.
[16:15:03 CEST] <kepstin> it's only the predictive lossless coding that's not supported, you might be able to do a lossless encode that's intra-only which would work :/
[16:15:12 CEST] <kepstin> not sure tho
[16:15:27 CEST] <furq> odinsbane: do the specs say that it has to work with quicktime
[16:15:45 CEST] <furq> if so then yeah you should go and shout at someone
[16:16:03 CEST] <odinsbane> furq: no, but everybody that I work with wants to see the video and they use quicktime.
[16:16:38 CEST] <odinsbane> Ill just use qp 18 so everybody can see it and complain about how tiny the output video is.
[16:16:55 CEST] <furq> you should use crf over qp 99% of the time
[16:18:04 CEST] <kepstin> (most of the remaining 1% of the time is lossless mode, where -qp 0 is preferred)
[16:19:07 CEST] <odinsbane> crf 18 works too, so Ill use that.
[16:21:32 CEST] <kepstin> crf 18 will give a pretty high quality (visually) encode, but if this is an intermediate file that might be re-encoded a few more times, I'd probably use a lower setting (higher quality).
[16:22:35 CEST] <odinsbane> The same file will probably not be re-encoded. I really suspect something is wrong with these specs.
[16:22:53 CEST] <odinsbane> Ill keep it in mind though when we are on the final version.
[16:25:45 CEST] <kepstin> (crf numbers are similar scale to qp numbers, except they take psy optimizations into effect - so the actually selected qp will vary per frame - or per macroblock even - based on frame complexity and motion)
[16:25:54 CEST] <farfel> good morning
[16:26:29 CEST] <farfel> if avcodec supports two codecs for the same file type, is there a way of forcing it to use a particular codec ?
[16:27:44 CEST] <kepstin> farfel: sure, using the -codec option (e.g. -codec:v or -c:v to select video codec)
[16:28:36 CEST] <farfel> kepstin: thanks a lot. In my case, I have vlc linking to avcodec. Is there an API for doing this from another program ?
[16:29:11 CEST] <kepstin> farfel: are you using vlc or developing it?
[16:29:23 CEST] <farfel> a bit of both :)
[16:29:30 CEST] <kepstin> if using, you'll want to talk to the vlc folks to see if they provide a ui or interface to do it
[16:30:01 CEST] <farfel> thanks, I have been talking to them
[16:30:16 CEST] <kepstin> when using libavcodec, you can just select an encoder or decoder using an exact name (e.g. 'libvpx-vp9' instead of the generic tag ('vp9')
[16:30:52 CEST] <farfel> ok, cool. so for jpeg 2000, it would be libopenjpeg-jp2k  ?
[16:30:57 CEST] <farfel> I think jp2k is the fourcc
[16:31:50 CEST] <kepstin> the generic name for that in ffmpeg is 'jpeg2000'. I don't have multiple encoders enabled in my build, so I'm not sure the name. You can try running "ffmpeg -codecs | grep jpeg2000" to see what you have.
[16:32:36 CEST] <farfel> kepstin: thanks, I really appreciate the help here
[16:33:51 CEST] <farfel> ok, so the name of the openjpeg decoder is libopenjpeg, and the native one is called jpeg2000
[16:34:30 CEST] <kepstin> yeah, the native one usually has the same name as the generic format name, so it's preferred by default in most cases.
[16:47:29 CEST] <farfel> kepstin: so, in vlc, if it uses the generic tag for jpeg 2000, would that be jp2k ?
[16:48:00 CEST] <kepstin> no, it would be 'jpeg2000'; 'jp2k' isn't a codec name (although it might be an alias, i'm not sure)
[16:48:18 CEST] <farfel> well, in vlc code, I can't find any reference to jpeg2000
[16:48:25 CEST] <kepstin> what's the container format?
[16:48:40 CEST] <kepstin> it might be just using the "default codec" pulled from the container
[16:48:58 CEST] <farfel> ok, in my case, I am trying to add support for still j2k images to vlc
[16:49:07 CEST] <farfel> so, a bit unusual for a video player, I guess
[16:49:24 CEST] <kepstin> btw, encoding or decoding?
[16:49:36 CEST] <farfel> decoding
[16:51:07 CEST] <kepstin> hm. as a still image, i'd guess it's probably using the image2 demuxer, which recognizes the j2k extension, and gives the codec AV_CODEC_ID_JPEG2000, which would cause it to use the default jpeg2000 decoder.
[16:51:35 CEST] <kepstin> is there some particular problem you're having with the internal jpeg2000 decoder?
[16:52:41 CEST] <farfel> Thanks. native decoder seems to have problems opening files from the openjpeg conformance suite
[16:53:33 CEST] <kepstin> you'd have to add some code to vlc to load a particular decoder (only if available in the ffmpeg build) rather than the default for that codec id if you want to do that.
[16:54:13 CEST] <kepstin> obviously it would be best to get the internal jpeg2000 decoder fixed to decode the test files correctly ;)
[17:03:29 CEST] <farfel> kepstin: yes, absolutely
[17:03:42 CEST] <farfel> these are conformance images, so not too pathological
[17:05:32 CEST] <farfel> kepstin: actually, I see that vlc uses AV_CODEC_ID_JPEG2000
[17:05:43 CEST] <farfel> so, what would I need to change it to to use libopenjpeg ?
[17:06:19 CEST] <farfel> oh, sorry, never mind
[17:06:40 CEST] <farfel> as you said, this loads the default
[17:07:23 CEST] <kepstin> farfel: probably have to switch from avcodec_find_decoder to avcodec_find_decoder_by_name("libopenjpeg") - and make sure to fallback if that codec's not available.
[17:07:41 CEST] <farfel> awesome, thanks a lot
[17:08:16 CEST] <farfel> I see in avcodec that both libopenjpeg and native decoder share the same id
[17:08:27 CEST] <farfel> AV_CODEC_ID_JPEG2000
[17:08:42 CEST] <kepstin> yeah, that identifies the codec itself, not any particular implementation
[17:08:56 CEST] <farfel> I see, thanks
[17:10:01 CEST] <kepstin> the avcodec_find_decoder finds more or less the "best" decoder for that codec, depending on some relative ordering the ffmpeg devs did and experimental flags.
[17:11:36 CEST] <farfel> ok, thanks
[17:11:57 CEST] <farfel> this is very helpful
[17:19:04 CEST] <farfel> kepstin: as an experiment, is it possible to re-order the codecs to put libopenjpeg at the front?
[17:21:34 CEST] <farfel> actually, never mind, need to fix this in vlc
[17:21:41 CEST] <farfel> if
[17:37:24 CEST] <farfel> kepstin: so it looks like vlc is failing to process these images for other reasons, it is not the codec
[17:37:28 CEST] <farfel> so that is good news
[17:37:48 CEST] <farfel> get_buffer() failed for some reason
[17:38:13 CEST] <grrk-bzzt> Hello
[17:38:40 CEST] <grrk-bzzt> To have a lossless x265 video, should I use -qp 0 or -x265-params lossless=1 ?
[17:39:31 CEST] <farfel> I forced vlc to use libopenjpeg, but still errors out
[17:39:54 CEST] <kepstin> farfel: did it return an error code or print a message?
[17:40:08 CEST] <kepstin> farfel: ffmpeg has some arbitrary limits on image size and memory, iirc
[17:40:38 CEST] <farfel> yes, prints an error message  [libopenjpeg 0xXXXXX] get_buffer() failed
[17:41:26 CEST] <farfel> ahhh, yes, but, ffmpeg can read these images
[17:41:27 CEST] <kepstin> grrk-bzzt: I think you have to use the -x265-params option.
[17:41:37 CEST] <kepstin> grrk-bzzt: the x265 site says "Note that QP 0 does not cause lossless encoding, it only disables quantization."
[17:41:38 CEST] <farfel> no problem
[17:41:46 CEST] <grrk-bzzt> thank you kepstin
[17:41:59 CEST] <farfel> perhaps ffmpeg doesn't use the same code path
[17:42:01 CEST] <farfel> as vlc
[17:42:16 CEST] <kepstin> the ffmpeg cli tool is definitely a different code path than vlc.
[17:42:35 CEST] <kepstin> but I'm not sure why it would change a get_buffer failing inside the decoder.
[17:43:51 CEST] <farfel> there are four error messages, thread_get_buffer() error, get_buffer() error, thread_get_buffer() error, get_buffer() error
[17:44:10 CEST] <farfel> for each image load attempt
[17:46:57 CEST] <farfel> unfortunately, the error code is not logged
[17:48:13 CEST] <farfel> I can add more debugging information to see what is going on
[17:48:39 CEST] <kepstin> farfel: Hmm. is vlc overriding the get_buffer(2) callbacks on the codec context?
[17:49:14 CEST] <kepstin> could be something in the vlc code, if that's the case :/
[17:49:17 CEST] <farfel> overriding ? not sure
[17:49:20 CEST] <farfel> let me check
[17:49:45 CEST] <farfel> what code should I look for?
[17:49:48 CEST] <farfel> for override ?
[17:50:07 CEST] <kepstin> something setting the get_buffer or get_buffer2 member on an AVCodecContext somewhere
[17:50:44 CEST] Action: kepstin is heading out; good luck.
[17:51:36 CEST] <farfel> ok, thanks very much for your help!
[18:00:10 CEST] <dbugger> Hello everyone
[18:01:30 CEST] <dbugger> Can anyone please take a look at my command? http://hastebin.com/ehimevalap.erl I am taking 3 videos, putting them on top of one another, and then putting them next to another media, but for some reason the first columns is 872px, and should be 874px... what did I do wrong?
[18:14:33 CEST] <Jookia> Extracting audio out of a 1:17:26 matroska stream gives me a 1:17:17 desynced track- are there tools I can use to extract it accurately?
[18:36:50 CEST] <Jookia> Okay, I just needed to use the resampling filter! Yay
[19:28:44 CEST] <dbugger> Can someone please take a look at my question? http://stackoverflow.com/questions/37418785/composition-on-ffmpeg-does-not-match-sizes?noredirect=1#comment62344315_37418785
[20:26:01 CEST] <lilibox> hi
[20:27:01 CEST] <lilibox> does anybody could point me at page where is describet the best setting for this: i have got sequence of .dpx files, one .wav and i need to mix it together to one nice .h264 2k standard file
[20:27:23 CEST] <lilibox> unfortunaly i don't have time to experimenting :(
[20:27:41 CEST] <lilibox> any well known preset for this avaiable around?
[20:27:47 CEST] <lilibox> thank you
[20:29:23 CEST] <BtbN> .h264 isn't exactly a standard file.
[20:29:30 CEST] <BtbN> Also, it's raw h264 video, so no audio.
[20:30:41 CEST] <lilibox> well, my video is targeted to one electro store, it will be played from USB stick directly on TV set probably
[20:31:46 CEST] <lilibox> i do graphics, but i put all my outputs as sequence of 10bits .dpx files, rest is on guys from post/broadcast department
[20:32:03 CEST] <JEEB> mp4 with level 4.1 H.264, AAC
[20:32:04 CEST] <JEEB> done
[20:32:06 CEST] <lilibox> so, i have not much experiences with video formats on tvs :(
[20:32:19 CEST] <lilibox> i will let it on yours guys, i belive you :)
[20:32:36 CEST] <lilibox> JEEB ok, level 4.1 means what?
[20:33:06 CEST] <JEEB> it's setting a limit to the encoder to not make a stream that requires more memory/bandwidth from the decoder than defined in that given level in the H.264 spec
[20:33:21 CEST] <JEEB> 4.1 is usually used with HD for most HW decoders, as it tends to be supported
[20:33:53 CEST] <JEEB> profiles = features, levels = (max) requirement of RAM/bandwidth from the decoder for the stream
[20:33:56 CEST] <JEEB> in H.264
[20:34:42 CEST] <lilibox> ok, soo, please could you point me or write it out directly here, which command sequence i should use? as i said, i have got sequence of .dpx in one folder - named video and in second folder named audio is one stereo .wav file
[20:34:53 CEST] <JEEB> the audio part is simple
[20:35:02 CEST] <JEEB> the multiple dpx files is not gonna be
[20:35:41 CEST] <JEEB> there's an image2 input "format" which lets you give a string format thing for multiple images, but I'm definitely not sure if dpx is supported with that
[20:35:52 CEST] <JEEB> other than that, it should be rather simple
[20:36:56 CEST] <JEEB> ffmpeg [stuff for the video input] -i audio/input.wav -c:v libx264 -c:a aac -level 41 -vf scale=-2:1080,format=yuv420p out.mp4
[20:37:09 CEST] <lilibox> ok, thank you for small edu lessons, i am going to finish shot and then will tell you
[20:37:21 CEST] <lilibox> JEEB great, it is exactly, what i wanted to see
[20:37:22 CEST] <lilibox> :)
[20:37:47 CEST] <JEEB> ffmpeg cli by default selects one video and audio stream, so if you just put two -i (inputs) with one having video and the other audio, it should "just work"
[20:38:01 CEST] <lilibox> ok
[20:38:20 CEST] <JEEB> rate control for libx264 by default is the equivalent of "-crf 23", so if it looks bad you set a lower CRF value, and if it looks good and you want to compress it more you push it upwards
[20:38:35 CEST] <JEEB> (the idea with CRF is to find the highest CRF value that still looks good to you)
[20:38:53 CEST] <JEEB> not sure about the default rate control for the internal aac encoder, but it should be sane enough
[20:39:12 CEST] <JEEB> (if not, do -b:a 192k which sets audio bit rate to 192 kilobits per second)
[20:39:40 CEST] <JEEB> buut yea, the image input is probably the hardest part for you :P
[20:39:49 CEST] <JEEB> which I conveniently left out
[20:40:01 CEST] <lilibox> ok, i am off for a while, thank you much again
[20:40:08 CEST] <JEEB> as I haven't used the image2 stuff and I don't know if it works with your image format
[20:41:43 CEST] <furq> do you really want -2:1080 over 1920:-2
[21:08:46 CEST] <kbarry> So, I'm trying to 1) detect silence on a stream, and 2) Alert.
[21:09:38 CEST] <kbarry> In my search, I came across SilentJack, but am not sure that its rea''y what I need. It might be that I am just too much a newb to really understand how JACK/SilentJack work,
[21:27:49 CEST] <lilibox> back
[21:28:45 CEST] <lilibox> and please does ffmpeg do not support  imagefilename.0012.dpx name convention?
[21:31:42 CEST] <JEEB> image2 has a hack for setting an input file name template
[21:31:45 CEST] <JEEB> in general, no
[21:32:08 CEST] <JEEB> https://www.ffmpeg.org/ffmpeg-all.html#Examples-7
[21:32:30 CEST] <JEEB> if setting the sequence string correctly doesn't work then sorry, nope
[21:32:38 CEST] <lilibox> JEEB your link ended with this error: error opening filters
[21:32:50 CEST] <JEEB> wat
[21:32:53 CEST] <lilibox> i just put ffmpeg.exe to windows folder
[21:33:02 CEST] <lilibox> no other files used ad mine side
[21:33:27 CEST] <JEEB> full command line and terminal output to pastebin or gist, please
[21:33:32 CEST] <JEEB> otherwise you are making no sense
[21:33:43 CEST] <JEEB> also the page is long so make sure you have the browser load the page
[21:33:45 CEST] <lilibox> i got something like this: Size value less than -1 are not acceptable.
[21:34:03 CEST] <pandaologist> hey, trying to find a volume meter filter that shows the volume on a logarithmic scale
[21:34:06 CEST] <pandaologist> https://ffmpeg.org/ffmpeg-filters.html#showvolume
[21:34:18 CEST] <pandaologist> this appears to be a linear scale
[21:34:36 CEST] <pandaologist> is anyone aware of another way to display in log?
[21:34:51 CEST] <JEEB> lilibox: stop guessing if any random part you happened to notice is useful for debugging or not. you clearly have no idea what you're doing so please post full command line and terminal output on a pastebin or gist
[21:34:56 CEST] <JEEB> whichever is simpler for you
[21:34:57 CEST] <lilibox> and second line [Parsed_scale_0 @ 020987e0] Failed to configure output pad on PArsed_scale_0 Error opening fileters!
[21:35:10 CEST] <JEEB> ok, it's clear you don't want to be helped. have a nice evening
[21:35:50 CEST] <lilibox> oh, wait, i just retyped what other window shows, sorry
[21:36:11 CEST] <lilibox> i didn't read what are you typeing :(, sorry
[21:36:31 CEST] <JEEB> you can select text in cmd.exe by right clicking the terminal
[21:36:45 CEST] <JEEB> both complete command line and terminal output
[21:36:48 CEST] <kepstin> pandaologist: as far as I can tell, that filter is doing the volume in decibels, which is a logarithmic scale.
[21:36:49 CEST] <lilibox> yes, i will paste it to pastebin and send you link in a while
[21:36:55 CEST] <JEEB> thank you
[21:37:09 CEST] <pandaologist> kepstin: the value displayed is in decibel correct
[21:37:27 CEST] <pandaologist> but the scaling of the volume bars (the visual representation) is definitely linear
[21:38:58 CEST] <kepstin> hmm, the code in that filter is not very obvious at all :/
[21:39:28 CEST] <lilibox> JEEB: http://pastebin.com/s7dkBq0Q
[21:39:44 CEST] <pandaologist> yeah, just looking to see if it's a simple change too
[21:40:28 CEST] <furq> lilibox: that's a really old version of ffmpeg
[21:40:36 CEST] <furq> i assume it predates the ability to use -2 in the scale filter
[21:40:39 CEST] <JEEB> lilibox: that's old enough to not have -2 which is a shorthand
[21:40:45 CEST] <JEEB> just grab a new one from zeranoe's
[21:40:53 CEST] <JEEB> since the AAC encoder is vastly superior now too
[21:41:00 CEST] <lilibox> ok
[21:41:06 CEST] <JEEB> https://ffmpeg.zeranoe.com/builds/
[21:44:38 CEST] <vade> hey JEEB - so converting my codebase to use an intermediary AV_TIME_BASE representation fixed like 90% of my problems. Only thing remaining that I cant quite hone in on is whom / what  is responsible for altering packets if I use an AVFilter which uses a source and a sink that have different sample rates.
[21:45:30 CEST] <vade> if I feed in 44.1 audio samples to my filter chain, and write out 48Khz audio, I get a shorter audio track
[21:45:41 CEST] <vade> but its *not* shorter by the ratio of 48/44.1
[21:47:16 CEST] <lilibox> JEEB thanks, seems like .mp4 works fine
[21:47:38 CEST] <lilibox> gotta put it on usbstick and check it on tv set
[21:48:07 CEST] <JEEB> and you checked that the quality was good enoguh? no need to poke the CRF value?
[21:48:21 CEST] <JEEB> but yeah, checking with a TV set makes sense
[21:48:31 CEST] <JEEB> also I guess you set frame rate accordingly
[21:48:49 CEST] <JEEB> seems like you didn't at least in the pastebin example
[21:48:54 CEST] <JEEB> default just happens to be 25Hz
[22:09:54 CEST] <lilibox> quality was fine, well, i forgot to tell you, that this clip had added Kodak film grain
[22:10:34 CEST] <furq> if you want to preserve the grain then try -tune grain
[22:10:41 CEST] <JEEB> not required
[22:10:59 CEST] <JEEB> if the quality is good enough for him, then no further tweaking is required
[22:11:29 CEST] <JEEB> lilibox: just make sure your frame rate is correct (without setting anything it's 25Hz/fps)
[22:11:32 CEST] <furq> well i mean technically nothing is required on account of the universe is dying and all human endeavour is pointless
[22:11:40 CEST] <JEEB> -_-
[22:11:46 CEST] <furq> but we have to while away the time somehow
[22:11:48 CEST] <lilibox> yes, PAL region here
[22:11:51 CEST] <JEEB> ok
[22:12:31 CEST] <JEEB> so yeah, check the clip on your hw device(s) and then you're done
[22:27:23 CEST] <Ricardo_> Hi all.   Can anyone point me to docs that explain how I can reconstruct a RFC6381 compliant codec string based on the ffprobe output?  (e.g., "avc1.42E01E")
[22:28:54 CEST] <thebombzen> I have a question - I'm trying the new OCR filter that uses tesseract. Is there any way to get it to dump the contents of OCR as soon as it encodes them?
[22:29:14 CEST] <Ricardo_> based on what i'm seeing, I can easily determine the profile (via a profile name) and the profile level... but I can't seem to find the byte containing the contraint_set flags.
[22:30:32 CEST] <wallbroken> ffmpeg -i input -vf "hflip,vflip,scale=1024:-2"
[22:30:33 CEST] <wallbroken> ffmpeg -i input -vf "transpose=1,scale=576:-2"
[22:30:44 CEST] <wallbroken> is there some difference between those commands?
[22:30:53 CEST] <wallbroken> asi i see, the first, rotates 180
[22:31:00 CEST] <wallbroken> the seconds, 90
[22:31:16 CEST] <wallbroken> but why the first uses hflip, vflip but the second uses "transpose" ?
[23:39:49 CEST] <kbarry> Are there tools to detect silence/dB levels in ffmpeg/play/probe/etc?)
[23:40:19 CEST] <kbarry> I can't find anything specifically, but thought maybe it just wasn't being done, but was certainly possible.
[23:40:50 CEST] <furq> http://ffmpeg.org/ffmpeg-filters.html#silencedetect
[23:42:15 CEST] <spooooon> I have decode AVFrames, I wish to display them using opengl
[23:42:51 CEST] <spooooon> how can I pull the data out of the AVFrame, it looks like the data* is actualy 3 data* and it doesn't look very helpful
[23:43:46 CEST] <spooooon> am I forced to use sws_scale?
[23:44:54 CEST] <kepstin> well, in most cases you'll have planar YUV video...
[23:45:41 CEST] <kepstin> depending what you want to do with the video, you could use libswscale to turn it into a different pixel format
[23:45:41 CEST] <spooooon> I was planning to convert to RGB in the shaders with opengl
[23:46:25 CEST] <kepstin> for planar yuv, you could do something like upload it as 3 separate textures, and have the shaders sample from all of them separately.
[23:46:25 CEST] <spooooon> I just wanted to pass it to an opengl texture
[23:46:32 CEST] <spooooon> oh I see
[23:46:38 CEST] <spooooon> planar YUV is 3 textures
[23:46:41 CEST] <spooooon> that makes sense
[23:46:54 CEST] <spooooon> sorry I'm new to video processing, thanks!
[23:47:42 CEST] <kepstin> yeah, unless you look into how different pixel formats work and are laid out in memory, you're gonna have a hard time with this.
[23:48:09 CEST] <spooooon> can't I always have the output from the decoder output into AV_PIX_FMT_YUV410P?
[23:48:17 CEST] <spooooon> then assume that is always the same
[23:48:27 CEST] <spooooon> I'm only supporting H264, MJPEG and MPEG4
[23:48:38 CEST] <furq> h.264 can be rgb
[23:49:02 CEST] <furq> and they can all be yuv422 or yuv444 iirc
[23:49:31 CEST] <spooooon> so I'm in for a bad time unless I use sws_scale?
[23:49:34 CEST] <furq> you could just have swscale convert it to 4:2:0 but in that case you might as well just have it output rgb
[23:49:46 CEST] <kepstin> most of the time you will get yuv420p from those formats, but they could be in something else :/
[23:50:16 CEST] <spooooon> The problem is I could have lots and lots of video feeds, I'm trying my best to increase performance
[23:50:25 CEST] <spooooon> and one way was to do conversions and scaling on the gpu
[23:50:45 CEST] <kepstin> why are you writing your own opengl output anyways? you should be able to grab the one e.g. from mpv/mplayer
[23:50:55 CEST] <furq> i believe zscale does higher-performance format conversions than swscale
[23:50:58 CEST] <kepstin> which I think does support several pixel formats
[23:50:59 CEST] <furq> it's still on the cpu though
[23:51:17 CEST] <spooooon> It's part of a much larger applciation
[23:51:53 CEST] <spooooon> I would be happy with doing the colour conversion on the CPU
[23:52:09 CEST] <spooooon> is sws_scale the correct function to be looking at to only do colour conversion
[23:52:43 CEST] <kepstin> yes, it can do color conversions without any scaling (has optimized codepaths for some common conversions, iirc)
[23:52:52 CEST] <spooooon> cool thanks
[23:53:08 CEST] <kepstin> or look into the zscale filter that furq mentioned, it can do that too, I think.
[23:55:26 CEST] <furq> i think someone mentioned it's multithreaded, which swscale isn't
[23:55:54 CEST] <spooooon> I have already seperated the workload into threads
[23:56:06 CEST] <furq> it's not a noticeable difference when you're doing it alongside an x264 conversion though
[23:56:20 CEST] <furq> which is the only time i've ever used it
[00:00:00 CEST] --- Wed May 25 2016