Re: [CinCVS] YUV4MPEG stream too dark
Herman Robak wrote: > On Sat, 29 Dec 2007 09:09:45 +0100, Craig Lawson > <[EMAIL PROTECTED]> wrote: > >> This is a rather esoteric issue, and it caused me grief for a long time. >> Here's a UI proposal: offer an option to apply ITU-R BT.601 color space >> conversion in the render dialog, with a tool tip suggesting you probably >> want it for MPEG. The option would give a hint to the clueless, and >> experts can use the RGB - 601 filter as they see fit. > > Let's take a step back, and figure out what is going on and what > The Right Thing To Do actually is... > > Is this dark output only produced by YUV4MPEG, and not when you render > to MPEG video with Cinelerra directly? If so, why? > > If ITU-R BT.601 is the right colourspace for conformant MPEG video, > then the codec should do that conversion when needed. It would be a > pain if certain codecs need "special treatment". The trouble is (as > far as I understand it) to discover when it IS needed. Cinelerra can > know that, but whatever command line you attach to the YUV4MPEG pipe > may not. And since the pipe interface is opaque to Cinelerra; it > doesn't know what the codec in the other end does, Cinelerra can not > decide if a conversion is needed or not. > > Is the paragraph above a fair summary of the problem here? > > > Now, to see what would be the least fuss for the most users, we need > to know which codecs need the colourspace conversions, and which don't. > Bring on the special cases! > Good point, and I agree. My trouble was also with YUV4MPEG for DVD production, using mpeg2enc. If there is a 601 conversion filter which can be inserted into the pipe, then Cinelerra's YUV4MPEG menu can include it. ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
Re: [CinCVS] YUV4MPEG stream too dark
On Sat, 29 Dec 2007 09:09:45 +0100, Craig Lawson <[EMAIL PROTECTED]> wrote: This is a rather esoteric issue, and it caused me grief for a long time. Here's a UI proposal: offer an option to apply ITU-R BT.601 color space conversion in the render dialog, with a tool tip suggesting you probably want it for MPEG. The option would give a hint to the clueless, and experts can use the RGB - 601 filter as they see fit. Let's take a step back, and figure out what is going on and what The Right Thing To Do actually is... Is this dark output only produced by YUV4MPEG, and not when you render to MPEG video with Cinelerra directly? If so, why? If ITU-R BT.601 is the right colourspace for conformant MPEG video, then the codec should do that conversion when needed. It would be a pain if certain codecs need "special treatment". The trouble is (as far as I understand it) to discover when it IS needed. Cinelerra can know that, but whatever command line you attach to the YUV4MPEG pipe may not. And since the pipe interface is opaque to Cinelerra; it doesn't know what the codec in the other end does, Cinelerra can not decide if a conversion is needed or not. Is the paragraph above a fair summary of the problem here? Now, to see what would be the least fuss for the most users, we need to know which codecs need the colourspace conversions, and which don't. Bring on the special cases! -- Herman Robak ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
Re: [CinCVS] YUV4MPEG stream too dark
Yes, that would be a very good idea, because this problem made me quite desperate. I searched the mailing lists but couldn't find anything. Now I see that the manual does mention something about the RGB - 601 filter, but when I searched the manual I searched for "brightness" and not "contrast", so I didn't find it. Craig Lawson wrote: This is a rather esoteric issue, and it caused me grief for a long time. Here's a UI proposal: offer an option to apply ITU-R BT.601 color space conversion in the render dialog, with a tool tip suggesting you probably want it for MPEG. The option would give a hint to the clueless, and experts can use the RGB - 601 filter as they see fit. Craig. Bas Alphenaar wrote: Thank you, it worked! Craig Lawson wrote: Bas, Try adding the "RGB - 601" filter to your video track(s). Configure the filter for "RGB -> 601 compression" (the default). Does that make it work? Craig. Bas Alphenaar wrote: Hello Cinelerra people, Today I tried to render out a movie I made with Cinelerra revision 1045 via a YUV4MPEG stream. However, the resulting video seems to be too dark compared to the video in the compositor. I turned on "Use Pipe" and used mencoder with the following commands: mencoder - -ovc x264 -x264encopts bitrate=3000 -o % mencoder - -ovc lavc -lavcopts vcodec=mjpeg:vbitrate=3000 -o % I also tried x264 and MJPEG with ffmpeg and they have the same problem. I think the problem lies with the YUV4MPEG stream that Cinelerra generates, because no matter what the codec or the encoding program is, the video is always too dark. Any suggestions? Or maybe this is a bug? Bas Alphenaar ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
Re: [CinCVS] YUV4MPEG stream too dark
This is a rather esoteric issue, and it caused me grief for a long time. Here's a UI proposal: offer an option to apply ITU-R BT.601 color space conversion in the render dialog, with a tool tip suggesting you probably want it for MPEG. The option would give a hint to the clueless, and experts can use the RGB - 601 filter as they see fit. Craig. Bas Alphenaar wrote: > Thank you, it worked! > > Craig Lawson wrote: >> Bas, >> Try adding the "RGB - 601" filter to your video track(s). Configure >> the filter for "RGB -> 601 compression" (the default). Does that make it >> work? >> >> Craig. >> >> >> Bas Alphenaar wrote: >>> Hello Cinelerra people, >>> >>> Today I tried to render out a movie I made with Cinelerra revision >>> 1045 via a YUV4MPEG stream. However, the resulting video seems to be >>> too dark compared to the video in the compositor. I turned on "Use >>> Pipe" and used mencoder with the following commands: >>> >>> mencoder - -ovc x264 -x264encopts bitrate=3000 -o % >>> mencoder - -ovc lavc -lavcopts vcodec=mjpeg:vbitrate=3000 -o % >>> >>> I also tried x264 and MJPEG with ffmpeg and they have the same >>> problem. I think the problem lies with the YUV4MPEG stream that >>> Cinelerra generates, because no matter what the codec or the encoding >>> program is, the video is always too dark. Any suggestions? Or maybe >>> this is a bug? >>> >>> Bas Alphenaar >>> >> >> ___ >> Cinelerra mailing list >> Cinelerra@skolelinux.no >> https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra >> > > ___ > Cinelerra mailing list > Cinelerra@skolelinux.no > https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra > > ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
Re: [CinCVS] YUV4MPEG stream too dark
Thank you, it worked! Craig Lawson wrote: Bas, Try adding the "RGB - 601" filter to your video track(s). Configure the filter for "RGB -> 601 compression" (the default). Does that make it work? Craig. Bas Alphenaar wrote: Hello Cinelerra people, Today I tried to render out a movie I made with Cinelerra revision 1045 via a YUV4MPEG stream. However, the resulting video seems to be too dark compared to the video in the compositor. I turned on "Use Pipe" and used mencoder with the following commands: mencoder - -ovc x264 -x264encopts bitrate=3000 -o % mencoder - -ovc lavc -lavcopts vcodec=mjpeg:vbitrate=3000 -o % I also tried x264 and MJPEG with ffmpeg and they have the same problem. I think the problem lies with the YUV4MPEG stream that Cinelerra generates, because no matter what the codec or the encoding program is, the video is always too dark. Any suggestions? Or maybe this is a bug? Bas Alphenaar ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
Re: [CinCVS] YUV4MPEG stream too dark
Bas, Try adding the "RGB - 601" filter to your video track(s). Configure the filter for "RGB -> 601 compression" (the default). Does that make it work? Craig. Bas Alphenaar wrote: > Hello Cinelerra people, > > Today I tried to render out a movie I made with Cinelerra revision > 1045 via a YUV4MPEG stream. However, the resulting video seems to be > too dark compared to the video in the compositor. I turned on "Use > Pipe" and used mencoder with the following commands: > > mencoder - -ovc x264 -x264encopts bitrate=3000 -o % > mencoder - -ovc lavc -lavcopts vcodec=mjpeg:vbitrate=3000 -o % > > I also tried x264 and MJPEG with ffmpeg and they have the same > problem. I think the problem lies with the YUV4MPEG stream that > Cinelerra generates, because no matter what the codec or the encoding > program is, the video is always too dark. Any suggestions? Or maybe > this is a bug? > > Bas Alphenaar > ___ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
