August 2022 - Cin - Cinelerra-GG Mailing Lists

Re: [Cin] Colors tip from forum
by Andrew Randrianasulu 02 Aug '22

02 Aug '22

вт, 2 авг. 2022 г., 20:10 Einar Rünkaru <einarrunkaru(a)gmail.com>: > Hi. > > On 02/08/2022 11:37, Andrea paz wrote: > > > Thanks for the responses; glad to hear from you again. > > In the CVE readme you mention the internal 16-bit color model. Since > > you remain the only deep Cinelerra expert (besides Adam, with whom it > > is difficult to interact), may I ask you to explain how color works in > > Cinelerra? Is it converted continuously as needed? > > Video is decoded to internal representation (look at settings/format). > Internal format is unpacked 3..4 values every pixel. CVE has only > RGBA-16 and AYUV-16 pixel formats. All values are 16 bit. > > CVO (and probably CGG) have 6 internal pixel formats (8-bit and float) > > > Does each plugin > > make the conversions it needs? > > All plugins see the frames only in internal format and modify this as > needed. > > > What do the color model settings affect > > and what are they affected by? > > Color model describes internal pixel format > > > Is it possible to implement ICC > > profiles? > > Probably. How? > Good question. I was looking into mplayer2's code for display part https://github.com/astiob/mplayer2/blob/all/libvo/vo_gl3.c Then I found news from yesteryear about lcms2 plugin https://littlecms.com/plugin/ "Little CMS floating point plug-in accelerates 8 bit and floating point color transforms, ".." The speedup is accomplished by implementing new interpolation kernels, adding optimizations and re-arranging memory layouts. Additionally, it can use SIMD instructions if present." Then there is new infrastructure in ffmpeg git: http://ffmpeg.org/pipermail/ffmpeg-devel/2022-July/299438.html https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/61ffa23c2e42887b32d469d9e69… "avcodec/codec_internal: add cap for ICC profile support" As far as I understand it only works with webp, tiff, png and mjpeg as video format but hopefully can be extended in future? > > In short, I am not clear about anything related to color > > treatment in Cinelerra. This is an issue that we have been dragging > > around for years (for example see the thread: > > > https://www.cinelerra-gg.org/forum/help-video/yuv-to-rgb-conversion-issues/ > ) > > but the confusion is total and we can't figure it out. > > Few mentions were made many years ago: > > https://lists.cinelerra-cv.org/pipermail/cinelerra/2018q4/009903.html > > https://www.mail-archive.com/[email protected]/msg13761.html > > Original Cinelerra does not care about colorspaces. It uses what comes > out from decoder. Some effects work differenlly depending on colorspace. > Sometimes pixel values are converted to float, sometimes to 8-bit for an > effect. Fixing it takes couple of man-years. > > CVE converts color to full-scale (0..65565). All effects work with full > scale values. Encoding converts to colorspace required by the codec. > > Einar > > PS Removed CinGG ML - it does not accept my mails - I am not subscribed. > > >

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Re: [Cin] Colors tip from forum
by Andrea paz 02 Aug '22

02 Aug '22

> The purpose of the plugin was to compare different color conversion > routines for testing. > The test is moved now to "Video Tests" plugin. Less confusion. > Einar Thanks for the responses; glad to hear from you again. In the CVE readme you mention the internal 16-bit color model. Since you remain the only deep Cinelerra expert (besides Adam, with whom it is difficult to interact), may I ask you to explain how color works in Cinelerra? Is it converted continuously as needed? Does each plugin make the conversions it needs? What do the color model settings affect and what are they affected by? Is it possible to implement ICC profiles? In short, I am not clear about anything related to color treatment in Cinelerra. This is an issue that we have been dragging around for years (for example see the thread: https://www.cinelerra-gg.org/forum/help-video/yuv-to-rgb-conversion-issues/) but the confusion is total and we can't figure it out. Few mentions were made many years ago: https://lists.cinelerra-cv.org/pipermail/cinelerra/2018q4/009903.html https://www.mail-archive.com/[email protected]/msg13761.html

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Re: [Cin] Colors tip from forum
by Andrea paz 01 Aug '22

01 Aug '22

> There was not fully implemented and disabled feature like this. It was > removed in commit "Removed unused dynamic folders feature from resources > window" (27 Dec 2013). > > Einar Hi, thanks for the info. I can't find the commit on git. May I ask why you removed The ColorSpace plugin from CVE? Is it not working well?

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