Ok, and next thing I tested: I started from scratch and tested step by step. When I only do an overlay of a PNG over my JPEG sequence, there is already a change in the color: white getting darker, black getting brighter.
Then I tested the same logo PNG, but overlayed it over a PNG sequence: and boom, NO color change compared to the version without overlay! So I think it has something to do with JPEGs being YUV coded and PNG being RGB. Overlaying them leads to colorchanges. Any ideas what I can do to have the combination of YUV and RGB working well in FFmpeg? Thanks, Abraham Am 07.08.2014 um 18:48 schrieb Schneider, Abraham: > Ok, I think I'm a step further: > > to keep colors correct from image sequences to the final QT, I found that it > helps to use a 'colormatrix=bt601:bt709' on the background. Working fine when > I use this as the only color filter. But when adding it with my overlay like > this: > > -vf "movie=watermark.png [logo]; [in]colormatrix=bt601:bt709[cc]; [cc][logo] > overlay=format=rgb:x=831:y=982 [out] > > the colormatrix changes the background video much more than when I use it > without the overlay. Anyone knows how I would add this colormatrix stuff > before I do the overlay? I'm quite new to this whole FFmpeg filter stuff, so > I may have this setup quite wrong. Would it be better to use 'filter_complex' > method? > > Thanks, Abraham > > > Am 07.08.2014 um 18:02 schrieb Schneider, Abraham: > >> Hi there! >> >> Sorry for abusing this group a little bit, but I have no idea where to ask >> this and maybe there are some people here who ran in the same problem >> already: >> >> I want to use FFmpeg to convert JPEG image sequences to Quicktime movies. >> All working fine so far. Now I also wanted to add text burnins and >> overlaying of the company logo. Text is also working fine, but the logo gets >> me strange results: >> >> I'm using the '-vf "movie=watermarklogo.png [watermark]; [in][watermark] >> overlay=10:10 [out]"' method. Problem is: as soon as I add this logo to my >> ffmpeg rendering, the color of my underlying video changes. It gets kind of >> brighter, or a gamma shift or so. >> >> I tried a premultiplied PNG, an unpremultiplied, same wrong result for the >> background. >> >> Does anyone know if it is possible to overlay a logo over a background in >> FFmpeg without changing the background, like a normal 'over' in Nuke? Any >> hints on how to do that and/or what might be wrong on my solution at the >> moment? How should the PNG file look like? 3 channels? 4 channels? >> Premultiplied? >> >> Thanks for any help, >> >> Abraham >> >> >> Abraham Schneider >> Head of VFX pipeline / VFX Supervisor >> >> >> Türkenstr. 89, 80799 München / >> Phone +49 89 3809-1096 >> >> EMail [email protected] >> >> Visit us on Facebook!________________________________ >> >> >> ARRI Film & TV Services GmbH >> Sitz: München Registergericht: Amtsgericht München >> Handelsregisternummer: HRB 69396 >> Geschäftsführer: Helge Jürgens, Josef Reidinger >> _______________________________________________ >> Nuke-users mailing list >> [email protected], http://forums.thefoundry.co.uk/ >> http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users > > _______________________________________________ > Nuke-users mailing list > [email protected], http://forums.thefoundry.co.uk/ > http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users _______________________________________________ Nuke-users mailing list [email protected], http://forums.thefoundry.co.uk/ http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users
