[Ffmpeg-devel-irc] ffmpeg.log.20160130

burek burek021 at gmail.com
Sun Jan 31 02:05:01 CET 2016

[00:04:17 CET] <spidergeorg> hello, how can I sharpen this using the unsharp filter without adding edge halos? http://puu.sh/mOEK6/40e7684e95.PNG
[00:04:35 CET] <spidergeorg> I'm afraid I don't quite understand the luma and chroma values
[00:05:16 CET] <spidergeorg> this not the actual resolution of the source so I used the 'area' scaling algorithm since it gave me the best looking results
[00:06:24 CET] <furq> if you're capping at native res then you should use neighbor
[00:07:03 CET] <spidergeorg> I'm deinterlacing by separating the fields though so I end up with video that's the correct width but half the height
[00:07:16 CET] <spidergeorg> and the resolution I'm resizing to isn't 1:1
[00:07:46 CET] <furq> use yadif mode 1 for deinterlacing if you want to keep the correct framerate
[00:07:51 CET] <TD-Linux> yes, try a different scaler such as nearest. using unsharp is only going to give you halos. that's what it does.
[00:09:08 CET] <furq> also fwiw that screenshot doesn't look like it's in need of sharpening
[00:09:37 CET] <furq> i know some weird people like ultra sharp pixel boundaries though
[00:09:43 CET] <spidergeorg> this is what using neighbor gives me http://puu.sh/mOF7U/91ccf6a73b.jpg
[00:10:22 CET] <spidergeorg> yadif blurs motion pretty badly
[00:10:51 CET] <furq> with mode 1?
[00:12:10 CET] <TD-Linux> is that analog capture of a super nintendo?
[00:12:36 CET] <TD-Linux> if so, and it's running in "240p", yadif is probably a bad idea actually
[00:13:06 CET] <spidergeorg> @td-linux yes, and yadif mode 1 gives everything in motion a sort of wet look
[00:13:14 CET] <spidergeorg> all of the hard edges are lost
[00:13:34 CET] <spidergeorg> which is why I decided to go with separatefields and resizing since I had to resize anyway
[00:13:51 CET] <durandal_170> trier nnedi 2x resize?
[00:14:00 CET] <durandal_170> *tried
[00:14:33 CET] <TD-Linux> yeah you probably actually want to deinterlace with just bob
[00:16:30 CET] <spidergeorg> isn't yadif=1:0 bob?
[00:17:14 CET] <spidergeorg> each field becomes a frame
[00:17:35 CET] <TD-Linux> I don't remember. but it looks like whatever you're doing is working so disregard me
[00:17:47 CET] <kepstin> yadif=1 turns fields into frames, but it interpolates the other field by guessing data rather than simply scaling like a bob
[00:17:49 CET] <TD-Linux> does nearest not look like what you want for scaling, btw?
[00:18:00 CET] <furq> 23:09:43 ( spidergeorg) this is what using neighbor gives me http://puu.sh/mOF7U/91ccf6a73b.jpg
[00:18:11 CET] <furq> that doesn't look like something anyone would want
[00:18:33 CET] <TD-Linux> ah it has the uneven sized pixels problem?
[00:18:40 CET] <spidergeorg> no neighbor is causing the pixels to look different sizes, which is understandable since it's not the original size
[00:19:07 CET] <spidergeorg> I'm just looking for a way to sharpen the resized video without adding bad edge halos
[00:19:11 CET] <TD-Linux> one thing you can try is doing an integer scaling with nearest neighbor (like 2x), then scaling to your final size with bilinear or whatever
[00:19:17 CET] <spidergeorg> the default values for unsharp look terrible
[00:19:52 CET] <spidergeorg> so double the scale using neighbor and then down scale?
[00:20:20 CET] <kepstin> spidergeorg: well, the way unsharp works is explicitly by "adding halos". The main thing you'll want to play with it is the blur radius setting, which effects how big the halos are.
[00:20:38 CET] <kepstin> in effect, if your halos from the unsharp are the same size as the blurriness, they cancel out
[00:20:39 CET] <spidergeorg> is there a way to mask just the edge halos?
[00:24:19 CET] <TD-Linux> spidergeorg, yeah
[00:24:57 CET] <TD-Linux> you can get a similar effect with some other filters but I don't think they are in ffmpeg
[00:25:15 CET] <furq> i'd have thought separating fields and resizing would give nasty horizontal shimmering
[00:25:33 CET] <TD-Linux> furq, well snes output isn't actually interlaced
[00:25:36 CET] <furq> i've never tried to capture from a snes though
[00:25:39 CET] <TD-Linux> (in most modes iirc)
[00:26:23 CET] <furq> i would suggest using a better deinterlacer but if that's not an issue then there's not much point
[00:27:10 CET] <furq> especially since using a better deinterlacer means using avisynth/vapoursynth
[00:28:45 CET] <spidergeorg> is this what you mean @furq? http://puu.sh/mOGq5/9bf750f345.png
[00:30:07 CET] <furq> no i mean the scanlines not lining up between frames
[00:30:42 CET] <furq> it causes shimmering in motion, particularly during static scenes
[00:30:51 CET] <furq> but if the snes doesn't actually output interlaced then that shouldn't be an issue
[00:31:33 CET] <spidergeorg> ah ok
[00:32:27 CET] <TD-Linux> furq, the snes messes up NTSC timing a bit so that on a CRT TV, the scanlines of each field are drawn on top of each other
[00:35:08 CET] <furq> well then the best suggestion i can offer is to just use snes9x
[00:35:15 CET] <spidergeorg> lol
[00:35:21 CET] <spidergeorg> you mean bizhawk ;)
[00:35:46 CET] <furq> are you recording tool-assists on a real snes
[00:35:48 CET] <furq> that's pretty hardcore
[00:36:19 CET] <furq> that would almost make up for the fact that you're playing yoshi's island
[00:36:42 CET] <spidergeorg> haha
[01:03:33 CET] <GuiToris> hello! is there an other way to trim my videos than $ ffmpeg -i clip -ss 00:01:00 -t 00:02:34 endresult.ogv?
[01:03:46 CET] <GuiToris> I would just simply add the end time, if it's possilbe
[01:03:59 CET] <furq> -to 00:03:34
[01:04:25 CET] <GuiToris> let's see, thank you furq :)
[01:07:21 CET] <GuiToris> awesome, works as expected. thank you once again
[01:16:23 CET] <spidergeorg> is it possible to output as a virtual device using solely ffmpeg?
[01:54:23 CET] <spidergeorg> if you're capturing from a device and outputting to a file is it live when you run it or is it recording?
[01:57:15 CET] <mattervr> wondering if someone can help me out with a nvenc_hevc hardware encoding issue.  Seems that I am unable to transcode prores or dnxhd to h265 using the hw accelerated nvenc_hevc codec.  Works just fine transcoding from h264.  I have a full trace log posted here http://pastebin.com/Q05KVbBS
[01:58:03 CET] <mattervr> is that a limitation of the nvenc_hevc encoder?  or do I need to re-compile ffmpeg with additional flags?
[01:58:37 CET] <mattervr> encoding fails with EncodePicture failed!
[01:58:37 CET] <mattervr> Video encoding failed
[06:43:41 CET] <spidersgeorg> it looks like it's possible to output to a window with opengl? would this be used with ffplay?
[06:46:15 CET] <spidersgeorg> I'm trying to figure out a way to create a virtual device as the output
[07:45:57 CET] <mmy> any one familiar with this error :
[07:45:58 CET] <mmy> [hls @ 0x1db8850]failed to rename file tmp to
[07:46:26 CET] <mmy> more details here : http://pastebin.com/kzxJdUVu
[08:03:42 CET] <mmy> no one ?
[08:03:49 CET] <mmy> [hls @ 0x1db8850]failed to rename file tmp to
[08:03:59 CET] <J_Darnley> I guess everone is still asleep
[08:27:25 CET] <vrfa> how can I improve playback using ffplay? I am dropping a ton of frames atm
[10:39:39 CET] <hurstly> is it possible to output to a null/blank file in windows like you can in linux via /dev/null/ ?
[11:10:01 CET] <SuperRoach> hello, how can i get ffmpeg to recognise a sequence like 0001.jpg ?    image2 -i %04d.jpg
[11:10:21 CET] <SuperRoach> Seems to not pickup the name. it's not %04d?
[11:22:46 CET] <relaxed> SuperRoach: that should work, pastebin.com your command and output
[11:23:02 CET] <SuperRoach> ok
[11:23:44 CET] <SuperRoach> http://pastie.org/10701533
[11:25:30 CET] <jkqxz> Remove the "-f image2"?
[11:28:20 CET] <SuperRoach> jkqxz, negative. yeah it does seem weird. I'll keep looking.
[11:28:37 CET] <relaxed> pastebin.com your command and and all console output
[17:30:24 CET] <luc4> Anybody who has ever seen a crash like this? http://pastebin.com/f7adHQ9W
[18:14:49 CET] <dystopia> has some commands changed in the new builds on Zeranoe?
[18:15:57 CET] <dystopia> my downloading commands have stopped working
[18:16:11 CET] <dystopia> ffmpeg -i %m3u8link% -cookies %cookie% -vcodec copy download.mp4
[18:16:23 CET] <dystopia> works in last build, and fails in current build
[18:18:16 CET] <dystopia> http://i.imgur.com/v9Opwwn.png
[18:47:10 CET] <redalert> Hello, the hls muxer is now generating segments without subtitles (if the stream has), and puts them in vtt files
[18:47:26 CET] <redalert> Is there any way to make the FFmpeg to use the old format for HLS, and the subtitles to be embed in the TS Segments?
[18:47:34 CET] <redalert> or i need to use the old FFmpeg version?
[18:47:59 CET] <redalert> didn't find any documentation for this
[18:51:31 CET] <dystopia> i have reverted to an old version
[21:46:32 CET] <spookypeanut> hello everybody
[21:46:58 CET] <spookypeanut> i'm on a mission to rip my dvds at the correct speed, despite the pal speedup https://en.wikipedia.org/wiki/576i#PAL_speed-up
[21:47:46 CET] <spookypeanut> i found this page, which is almost perfect: https://trac.ffmpeg.org/wiki/How%20to%20speed%20up%20/%20slow%20down%20a%20video
[21:47:59 CET] <spookypeanut> but it doesn't say anything about subtitles
[21:48:25 CET] <spookypeanut> i've tried several things, but can't find a way to speed up subtitles in a filter
[21:48:31 CET] <spookypeanut> does anyone know a way?
[21:48:47 CET] <J_Darnley> You will probably need another tool.  I don't think ffmpeg has features like that for subs (yet).
[21:49:34 CET] <J_Darnley> But look at the docs/help for various subtitle muxers/demuxers to see if they have some option for foring timing.
[21:54:05 CET] <mobilespooky> (Sorry, have been forced to go mobile to calm a screaming baby)
[21:55:07 CET] <J_Darnley> Shall I repeat my last two lines for you?
[21:59:44 CET] <mobilespooky> Yes please
[22:00:22 CET] <J_Darnley> You will probably need another tool.  I don't think ffmpeg has features like that for subs (yet).
[22:00:26 CET] <J_Darnley> But look at the docs/help for various subtitle muxers/demuxers to see if they have some option for foring timing.
[22:01:41 CET] <mobilespooky> OK, thanks, I'll investigate
[22:02:46 CET] <mobilespooky> I guess an option would be to pull them out to an srt, filter (manually? Need to look into file format) and re insert
[22:03:12 CET] <J_Darnley> Yes, that would work.
[22:03:43 CET] <J_Darnley> I don't know what tools you might use but SubRip definitely had that feature.
[22:04:19 CET] <mobilespooky> Cool, thanks for the info!
[22:05:03 CET] <c_14> You might be able to use aegisub, iirc it has such a feature.
[22:05:46 CET] <J_Darnley> That is probably a much better idea than ancient subrip.
[22:23:24 CET] <spookypeanut> damn, srt format is not an option, because my subtitles are from dvd (stored as bitmaps)
[22:23:38 CET] <spookypeanut> will investigate those tools you mentioned
[22:33:53 CET] <spookypeanut> hmmm, had a look at aegisub (subrip not an option, as i'm on linux), and it doesn't seem to do anything with bitmap subtitles
[22:34:19 CET] <c_14> Yeah, I was assuming text subs.
[22:34:41 CET] <c_14> Don't know of anything for bitmap subtitles. I avoid them.
[22:54:27 CET] <spookypeanut> yeah :-/ i guess a (bad) option would be to burn them into the video before changing the speed
[22:54:44 CET] <spookypeanut> i don't like it, but it would be better than nothing
[22:58:00 CET] <c_14> Maybe something like http://forum.doom9.org/archive/index.php/t-162721.html ? Try searching for "retime bitmap subtitles" or something
[23:07:21 CET] <spookypeanut> thanks, i'll have a look
[00:00:00 CET] --- Sun Jan 31 2016

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