[Ffmpeg-devel-irc] ffmpeg.log.20180924

[burek]

[00:02:29 CEST] <johnnny22> whats this v210 encoder actually do ? trying to figure out what it's doing internally. Is it transforming it to UYVY or is it just adjusting the paddings ?
[00:09:30 CEST] <JEEB> johnnny22: it takes in 4:2:2 planar and converts it to that weird bit-packed format that V210 is
[00:10:47 CEST] <johnnny22> ok, just wasn't sure what that WRITE_PIXELS was doing
[00:11:16 CEST] <johnnny22> it being called 4 times, and starting with u, y, v and y , i was pondering.
[00:15:39 CEST] <johnnny22> that bit-packing seems to take ~50% of a CPU (seems like the biggest bottleneck)
[04:05:53 CEST] <johnnny22> really wish there was a V210 pixfmt implementation. I know i know, there's a codec for it, but in my case i'd love to use rawvideo on it :P
[04:46:30 CEST] <tMH> ppl, I want to ask some small Q: when I get videofeed (street camera) I see nice hd picture. I decided to make some timelape - capturing one frame per minute, then combining those .jpg captures to one .mp4 - and I get somewhat lower quality than I have on those jpg caps. what command I use to combine them into one videofile is: cat 2018-09-24*.jpg | ffmpeg -framerate 24 -f image2pipe -i - output.mp4
[04:46:50 CEST] <tMH> could someone tell me - how to get _normal_ HD output in this videofile, not low quality one ?
[04:47:41 CEST] <tMH> for example, I have about 300mbytes of jpegs, and I get 17 mbytes .mp4 videofile as result.. it's clear that this combine command lower down quality...
[04:48:38 CEST] <tMH> thanks in advance:)
[05:08:27 CEST] <johnnny22> tMH: since you're exporting to mp4, maybe check the options available here: https://trac.ffmpeg.org/wiki/Encode/H.264
[05:09:28 CEST] <johnnny22> tMH: maybe check on that page under the "Lossless H.264" title :)
[05:15:49 CEST] <tMH> johnnny22: well... -f format is image2pipe...
[05:17:01 CEST] <tMH> johnnny22: I thought about another way to make .mp4 directly from that stream. I mean - to tell ffmpeg to capture videostream - 1 frame per minute, into .mp4 - so .jpg files will not be needed at all..
[05:18:48 CEST] <tMH> cat 2018-09-24*.jpg | ffmpeg -framerate 24 -c:v libx264 -preset veryslow -crt 0 -i - output24-22-23.mp4
[05:18:54 CEST] <tMH> no luck:)
[05:19:01 CEST] <tMH> ah, crf
[05:19:14 CEST] <tMH> Unrecognized option 'preset'.
[05:19:15 CEST] <tMH> Error splitting the argument list: Option not found
[05:54:39 CEST] <Matador> oh boy
[09:38:59 CEST] <linux> hi ,is there a way with ffmpeg to anonymize voice from a recording?? thanks
[09:41:08 CEST] <durandal_1707> linux: yes, see filters documentation
[09:42:03 CEST] <linux> durandal not any specific command recomendation?
[09:43:49 CEST] <durandal_1707> linux: depends what you want to accomplish exactly
[09:45:05 CEST] <linux> just want to modify my voice for my youtube channel ,to make it unrecognisable ,not sure what filters to play with
[09:53:44 CEST] <durandal_1707> linux: basically any distortion filter will do it
[09:56:06 CEST] <linux> durandal ,could you suggest any that would be nice?
[10:00:50 CEST] <durandal_1707> linux: ffmpeg -i voice.wav -f lavfi -i sine=400 -lavfi amultiply out.wav
[10:03:15 CEST] <linux> durangal THANKS! Ill play with that ,and later might study the distorsion filters!
[10:03:24 CEST] <durandal_1707> linux: there is more
[10:03:50 CEST] <durandal_1707> ffmpeg -i voice.wav -af vibrato=f=100 out.wav
[10:05:44 CEST] <linux> durangal THANKS
[10:29:14 CEST] <Matador> bloody heck
[10:37:01 CEST] <Matador> anyone around to troubleshoot somethin ?
[13:32:33 CEST] <horohoro55> Hello there. We took video of our vacation with a non branded Go Pro and it seems that one of the 2 SD card has a problem and all the video got corrupted. I am trying to repair them using ffmpeg but I do not know where to go.
[13:32:40 CEST] <horohoro55> This is the result of ffprobe, the first file is the file on the OK video. It's AVC MOV. The second is the corrupted one that should be the same format https://pastebin.com/jFNtZDHV
[13:33:20 CEST] <horohoro55> When I try to convert, it tells me that it is not sure to understand the input format. Can I indicate ffmpeg what is supposed to be the input format
[13:35:22 CEST] <durandal11707> horohoro55: it is missing important info, so thats why ffmpeg cant decode it
[13:35:30 CEST] <furq> horohoro55: it's not something that ffmpeg can fix
[13:35:42 CEST] <horohoro55> arf ... any idea what could ?
[13:35:47 CEST] <furq> there are tools that will fix it if you have a working file from the same device, but i couldn't recommend any in particular
[13:36:08 CEST] <furq> the only free one i know of requires an old version of libav to compile it
[13:36:16 CEST] <durandal11707> furq: really? ffmpeg can extract video from that file if you have pro skills
[13:36:34 CEST] <furq> well apparently i don't have pro skills
[13:37:07 CEST] <horohoro55> Anyway, I do not have this pro skill ^^. At least not at this level.
[13:37:08 CEST] <durandal11707> besides packets size and start offsets are all missing
[13:39:08 CEST] <horohoro55> "besides packets size and start offsets are all missing" you mean except if packet size and start offsets are missing, ffmpeg libs should be able to repair it with some crazy skills.
[13:39:17 CEST] <horohoro55> ?
[13:39:19 CEST] <durandal11707> there is no magic solution
[13:40:25 CEST] <durandal11707> horohoro55: one could try to extract video frames if he know start bits of frames
[13:41:11 CEST] <durandal11707> so it is lot of manual work...
[13:41:26 CEST] <furq> well yeah
[13:41:28 CEST] <horohoro55> I understand what you mean. Seems pretty hard indeed
[13:41:32 CEST] <furq> https://github.com/ponchio/untrunc
[13:41:33 CEST] <furq> http://djifix.live555.com/
[13:41:40 CEST] <furq> those are the two free tools i know of that might help
[13:41:45 CEST] <furq> there's a bunch of commercial stuff that does it as well
[13:42:46 CEST] <horohoro55> I work in broadcast so I might be able to get some commercial autoQC tools.
[13:43:41 CEST] <horohoro55> Let's try this untrunc thing, it seems really easy to set up
[15:22:11 CEST] <th3_v0ice> Is calling av_frame_free(&frame) enough to deallocate all memory allocated by AVFrame* frame = av_frame_alloc();?
[15:30:07 CEST] <kepstin> th3_v0ice: yes. note that additionally, av_frame_free() will unreference the buffers in the avframe as well, possibly freeing them.
[15:31:42 CEST] <th3_v0ice> kepstin: Can you explain this "possibly" part?
[15:32:41 CEST] <kepstin> depends on the reference count. a buffer is freed when its reference count drops to 0
[15:33:19 CEST] <kepstin> if multiple avframes reference the same buffer, free() on one frame won't free the buffer, but when you run free() on the second frame it will
[15:33:42 CEST] <th3_v0ice> So the only way to free the buffers is to remove all references.
[15:34:22 CEST] <kepstin> rather, reference counting ensures that the buffer won't be freed until all references are removed
[15:35:10 CEST] <th3_v0ice> Ok, thanks!
[15:57:11 CEST] <th3_v0ice> kepstin: One more question. If I pass the AVFrame to the av_buffersrc_add_frame_flags(..., AV_BUFFERSRC_FLAG_KEEP_REF) and the AVFrame is reference counted, do I need to free the reference after the method returns or is it automatically freed?
[15:58:42 CEST] <kepstin> th3_v0ice: according to the docs: https://www.ffmpeg.org/doxygen/4.0/group__lavfi__buffersrc.html#gga755c96456945ef03bae544705e8cca64a24758c8f4deed09b04b1be6c2e66a14e
[15:58:52 CEST] <kepstin> that causes the buffersrc to make its own new reference
[15:59:02 CEST] <kepstin> so you still have your original reference as well
[16:09:57 CEST] <th3_v0ice> So the buffersrc is freeing its own reference?
[16:10:58 CEST] <kepstin> buffersrc doesn't free anything - but a frame inside the filter chain needs to have a reference to get passed between filters
[16:11:51 CEST] <kepstin> you only need to use the KEEP_REF flag if you want to keep a reference yourself - i.e. if you want to access the buffer content after calling the add_frame() method
[16:12:28 CEST] <kepstin> without that flag, it "steals" the existing reference and buffer and resets your original avframe to be empty.
[16:25:06 CEST] <th3_v0ice> Ah, ok. Got it!
[17:09:03 CEST] <horohoro55> furq, durandal11707 hum ... it was a lost cause ... after opening with an hex editor I realized that the file is only full of 1s ... so there is no information in it ^^' I should have started with that. I played a bit with docker which is not a complete loss
[17:15:15 CEST] <sybariten> hey
[17:15:41 CEST] <sybariten> here's a suggested line from a stackexchange question. What does it actually/exactly do?   ffmpeg -i vlc-output.ts -c copy ffmpeg-output.ts
[17:17:39 CEST] <durandal11707> sybariten: not much, remuxes file
[17:18:10 CEST] <sybariten> Yeah, ok, but... what is that?
[17:21:17 CEST] <cslcm> it just transfers the streams out of the source .ts container into a new one. It can potentially/possibly fix playback issues if the source container is faulty and ffmpeg can decipher it
[17:24:48 CEST] <sybariten> cslcm: gotcha
[17:25:55 CEST] <sybariten> Im sitting with 26 gb of .mts video files that my Premiere editing suite doesnt like because they have dolby (i think its 5.1) sound, and transcoding sure doesnt seem to be as easy as i thought
[17:26:25 CEST] <sybariten> It's apparently an issue between Win7 and Premiere, if i understood correctly
[17:26:26 CEST] <Hello71> is there any documentation for which filters are actually good? :/
[17:26:55 CEST] <durandal11707> Hello71: there is documentation, do you know where it is?
[17:27:07 CEST] <Hello71> do you mean on trac?
[17:27:17 CEST] <durandal11707> Hello71: nope, on ffmpeg.org site
[17:27:28 CEST] <Hello71> you mean the same as the man pages?
[17:27:36 CEST] <Hello71> s/ same as//
[17:28:03 CEST] <durandal11707> man ffmpeg-filters
[17:28:41 CEST] <durandal11707> Hello71: also what you need?
[17:31:42 CEST] <Hello71> like, postprocessing beyond https://trac.ffmpeg.org/wiki/Postprocessing (which was down last I checked, but apparently it's fixed now)
[17:31:54 CEST] <Hello71> which deinterlace filter to use
[17:31:56 CEST] <Hello71> and whatnot
[17:32:46 CEST] <durandal11707> Hello71: all that depends on multiple factors
[17:34:11 CEST] <furq> does anyone still use the pp filters
[17:35:07 CEST] <sybariten> what keywords to i need to use to search for info on how to deconstruct a video container into sepoarate video and audio, and then rebuild a new file. With the least processing possible
[17:35:37 CEST] <furq> that's what the command you pasted does
[17:35:42 CEST] <durandal11707> sybariten: demuxing
[17:35:53 CEST] <durandal11707> and remuxing
[17:36:00 CEST] <sybariten> furq: me? I mean in separate steps. This isnt working at all
[17:36:10 CEST] <Hello71> also usually demuxing into separate files is useless
[17:36:23 CEST] <sybariten> I've tried a number of times, and i can't make this happen
[17:36:37 CEST] <durandal11707> sybariten: what error you get?
[17:36:46 CEST] <sybariten> Well, in the sence of making something that premiere eats afterwards, i should specify!
[17:37:21 CEST] <sybariten> durandal11707: hm, if i make an avi premiere says "unsupported format or damaged file"...
[17:37:30 CEST] <durandal11707> do you know what premiere eats?
[17:37:35 CEST] <durandal11707> probably mxf
[17:37:52 CEST] <sybariten> durandal11707: if i make a mov, i got only the audio, to my surprise. But the file has the same size, roughly, as the input... so the video is there. Well in fact the resulting file looked all fine in VLC
[17:38:02 CEST] <furq> remux to mp4 if you can
[17:38:12 CEST] <sybariten> durandal11707: it used to eat my MTS files... but there was a licensing thing that happened with a new vcersion now recently
[17:38:37 CEST] <furq> premiere only supports mpeg2video in mpegts iirc
[17:38:45 CEST] <sybariten> lots of people write about it online... and often the suggestion is to eithe rfind an older premiere version, or transcode with ffmpeg .. but i'm not luycky with that yet
[17:38:47 CEST] <furq> so if you have h264 then put it in mp4
[17:38:52 CEST] <furq> or ideally stop using premiere
[17:39:00 CEST] <furq> but i'm guessing that's not an option
[17:39:24 CEST] <sybariten> furq: first step to analyze _exactly_ what i have?
[17:39:37 CEST] <furq> ffprobe foo.ts
[17:39:49 CEST] <durandal11707> note that premiere probably supports only baseline h264
[17:39:50 CEST] <sybariten> no, it's a really really nice editing suite in many ways... whiuch is also surprisingly buggy for suchj a big corporation as Adobe
[17:40:33 CEST] <furq> well it uses os codecs so it's always going to be a big minefield
[17:41:01 CEST] <sybariten> furq:  https://pastebin.com/1spyBhx1
[17:41:44 CEST] <furq> yeah just remux that to mp4 (as long as you don't care about the subtitles)
[17:41:52 CEST] <furq> premiere should be ok with it then
[17:41:55 CEST] <sybariten> I'm guessing if i had only remembered to alter one freaking switch on my camcorder i could have avoided all this.....  5.1 audio .. shaking head
[17:42:00 CEST] <sybariten> there are no real subtitles
[17:42:12 CEST] <sybariten> gotta rush home, catch y'all later
[17:53:53 CEST] <cslcm> sybariten: you can downmix quite easily with ffmpeg
[17:54:14 CEST] <cslcm> depending on channel bias it can be more complex but from a camcorder i don't imagine it would be an issue
[17:56:32 CEST] <cslcm> see https://superuser.com/questions/852400/properly-downmix-5-1-to-stereo-using-ffmpeg
[19:26:06 CEST] <johnnny22> oh joy another codec 'Blackmagic RAW' :P
[19:27:45 CEST] <JEEB> yes, that popped up some time ago
[19:28:08 CEST] <JEEB> I wonder if it will have a similar hard-coded table like with prores raw
[19:28:12 CEST] <JEEB> for the debayer
[19:28:28 CEST] <JEEB> also both of those seem like really misleading names given the fact that they're not lossless
[19:28:31 CEST] <JEEB> lol
[19:29:03 CEST] <ChocolateArmpits> I think people using those formats care slightly about other features, like high bit depth
[19:29:31 CEST] <johnnny22> yeah, i really have no more details yet on this thing
[19:29:48 CEST] <johnnny22> all i see is https://www.blackmagicdesign.com/products/blackmagicursaminipro/blackmagicraw (which is populated by marketing words)
[19:29:49 CEST] <JEEB> there was a full document on the basics of it
[19:30:04 CEST] <JEEB> ChocolateArmpits: high bit depth is not really anything new in this space
[19:30:17 CEST] <JEEB> the main thing is that now they're supposedly taking it as a bayer thing because lol
[19:30:19 CEST] <kepstin> hmm, it's been fairly common for "raw" still image formats to be lossy, the main thing is usually higher bit depth and no debayer.
[19:30:53 CEST] <johnnny22> "Images are encoded using a custom non-linear 12-bit space designed to provide the maximum amount of color data and dynamic range." hehe
[19:31:03 CEST] <JEEB> kepstin: yes, unfortunately
[19:31:16 CEST] <johnnny22> gotta love the word "custom"
[19:31:35 CEST] <JEEB> anyways, IIRC blackmagic raw was supposedly partially debayered or something
[19:31:43 CEST] <JEEB> so they might not have made the mistake of prores raw :P
[19:32:28 CEST] <johnnny22> i obviously wouldn't be able to speak of the details
[19:32:57 CEST] <JEEB> I think someone already looked at the binary in a debugger but AFAIK no RE work has been done yet
[19:33:10 CEST] <JEEB> probably waiting for a bounty
[19:33:16 CEST] <johnnny22> lol
[19:33:42 CEST] <JEEB> which is understandable because most people using prores raw or blackmagic raw are not doing it for fun and skiddles
[19:33:50 CEST] <JEEB> so someone might as well sponsor it :P
[19:34:00 CEST] <johnnny22> i wonder how big a bounty would be required for this (just wondering how much might drive interest)
[19:34:22 CEST] <johnnny22> not that i need it atm
[19:34:59 CEST] <JEEB> not yet on https://wiki.videolan.org/Bounties
[19:35:46 CEST] <JEEB> DTS XLL extension (lossless) was 4000eur it seems
[19:36:19 CEST] <JEEB> MVC bounty is still around and 6000eur
[19:36:54 CEST] <JEEB> generally the price is driven by interest from various parties
[19:37:20 CEST] <johnnny22> oh neat, didn't know about that page
[19:41:05 CEST] <durandal11707> nobody is interested in doing it
[19:41:38 CEST] <johnnny22> what's MVC used for anyways :P
[19:41:46 CEST] <JEEB> I've seen it on some blu-rays
[19:42:08 CEST] <JEEB> durandal11707: also elenril showed his MVC code during VDD and I'm not sure if koda got him trolled enough to poke at "the last 20%" for it
[19:42:27 CEST] <durandal11707> iirc it encodes 3D in frame sequential order
[19:42:39 CEST] <JEEB> it is multiview yes
[19:42:42 CEST] <johnnny22> right, just got a glimpse at the wiki about it
[19:42:43 CEST] <JEEB> 99% of them are two
[19:42:57 CEST] <JEEB> in theory you could have like 40 or so views max?
[19:43:15 CEST] <JEEB> the base view is standard AVC so you always get the "base" view
[19:44:29 CEST] <johnnny22> interesting
[20:07:07 CEST] <Catatronic> i love you guys hard
[20:10:10 CEST] <durandal11707> Catatronic: why?
[20:11:00 CEST] <Catatronic> because you work on ffmpeg
[20:58:36 CEST] <myke> hello, i use -re to stream files.  is it possible to have an initial burst of data and then feed at realtime rate?
[20:59:55 CEST] <kepstin> myke: the -re option is very simple, all it does it sleep after reading each frame. If you want more control, you'd need to use or build a dedicated streaming app.
[21:00:12 CEST] <myke> ok ty
[21:33:31 CEST] <GuiToris> Hey, what did I mess up here? ffmpeg -framerate 25 -i "%d.png" -i ~/bird.mkv -map 0:v -map 1:a  -vf scale=1920:1080 -c:v libx264 -g 75 -c:a copy -crf 28 -preset slow bird2.mkv
[21:34:00 CEST] <GuiToris> I got a ~25mb video file, I can play back on my computer but I can't on our TV
[21:34:54 CEST] <GuiToris> I imported these images into photoshop and saved the video, and it can be played back everywhere
[21:35:12 CEST] <GuiToris> it's about 280mb
[21:35:43 CEST] <GuiToris> what could be the problem?
[21:36:00 CEST] <pzich> maybe it's an issue with the audio? hard to tell from just the command
[21:36:05 CEST] <poutine> GuiToris, we know nothing about your TV, its requirements, or method of playing it, what kind of video file does adobe produce?
[21:36:55 CEST] <GuiToris> even if I converted the file into mp4 afterwards it couldn't be played back
[21:37:06 CEST] <GuiToris> but I'll check the other video
[21:37:18 CEST] <GuiToris> h264 works, also acc and vorbis
[21:39:37 CEST] <poutine> GuiToris, posting mediainfo of your generated file and the adobe generated file might clear up the disconnect there
[21:39:48 CEST] <GuiToris> https://ptpb.pw/UhwO
[21:39:56 CEST] <GuiToris> https://ptpb.pw/D59K
[21:40:13 CEST] <GuiToris> sorry, it just took some time
[21:40:46 CEST] <GuiToris> only the audio can be played back on our TV and tablet
[21:40:59 CEST] <GuiToris> the video was mostly gray
[21:41:46 CEST] <ChocolateArmpits> GuiToris, what's the pixel format of the output video? I can't glee anything out of those logs
[21:41:58 CEST] <poutine> Can you use 'mediainfo' and not exiftool
[21:42:35 CEST] <GuiToris> sure thing
[21:44:57 CEST] <GuiToris> https://ptpb.pw/Nmzy
[21:45:04 CEST] <GuiToris> https://ptpb.pw/Sgw5
[21:45:36 CEST] <ChocolateArmpits> yep this is why Format profile                           : High 4:4:4 Predictive at L4
[21:46:06 CEST] <kepstin> yeah, if the input is png it's gonna give you 4:4:4
[21:46:07 CEST] <ChocolateArmpits> specify "-pix_fmt yuv420p -vprofile main" in your command line for most compatibility
[21:46:34 CEST] <kepstin> probably the "-pix_fmt yuv420p" is enough on its own unless you have a really strange tv :)
[21:47:04 CEST] <GuiToris> it has played back everything so far but this one
[21:47:19 CEST] <GuiToris> and you're right, the input files are pngs
[21:47:38 CEST] <kepstin> is this the first one where the input is png? all your other videos were probably already 4:2:0 subsampling.
[21:47:55 CEST] <kepstin> so it didn't need any option because it didn't need conversion
[21:48:12 CEST] <GuiToris> probably, I almost never make videos from image sequences
[21:48:49 CEST] <GuiToris> thank you for your help, I'll try this one -pix_fmt yuv420p -vprofile main
[21:49:50 CEST] <ChocolateArmpits> kepstin, well the reference video is in Main profile and that was confirmed to work so...
[21:56:05 CEST] <GuiToris> ChocolateArmpits, should I specify gop, if I won't edit this video?
[21:56:36 CEST] <GuiToris> I just randomly typed 75
[21:56:44 CEST] <ChocolateArmpits> GuiToris, if you won't, then it will be set at 10 seconds per gop
[21:57:41 CEST] <ChocolateArmpits> If you just intend to watch the video then there's nothing wrong with that, not to mention should offer better compression
[21:58:36 CEST] <GuiToris> thanks, then I'll leave out -g this time :)
[22:23:08 CEST] <shfil> has someone some resources about loading large audio files in c++? I mean streaming/async. (gave some 40MB files)
[22:23:15 CEST] <shfil> *have some
[22:33:26 CEST] <johnnny22> 40MB being a large file ? :)
[22:38:13 CEST] <kepstin> not really, no. I mean, even my old ipod classic with rockbox could buffer 40mb of audio files in ram :/
[22:39:19 CEST] <kepstin> loading 40mb synchronously in a gui thread should be avoided, since there's gonna be a bit of time to load that off disk of course.
[22:46:06 CEST] <shfil> yeah, I think about problem of freezing main thread when waiting for data.
[22:50:03 CEST] <kepstin> yeah, so this has nothing specific to media files, just gui app programming in general. You'd probably want to spawn a thread to do the reading/decoding. How exactly you handle that thread depends on the particular ui toolkit, main loop implementation, maybe even os you're using.
[22:59:22 CEST] <Matador> fun times
[00:00:00 CEST] --- Tue Sep 25 2018