Black Levels Terrible on XBMC
#16
(2013-12-05, 15:57)donkamillo Wrote: Will there be an option to set color range to 16-235 in the next XBMC release?

Regards!
I don't know if this is needed. It's probably better doing this at system's driver level.
EDIT: anyway, according with post #3, looks like the Team XBMC is providing this option. Its funny, since part of the Team-XBMC thinks that limit the signal is unnecessary. LoL.
This new option will probably help a lot of people. If works right, users will not need to know how to edit the xorg.conf file.

Best regards.
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#17
FireMan, you are completely immune to what developers say, aren't you?

@donkamillo yes, we have such an option in Gotham. But it has to be used carefully because some h/w decoders are not capable of converting yuv to RGB limited.
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#18
I can leave it in the xorg.conf because it gives me exactly the result I need. But it took me a while because I am no linux expert. So an option to set it up from the XBMC GUI would be nice.

There is another thing I don't understand. So XBMC outputs full RGB. As far as I understand it, my limited range videos are expandet to 0-255 and than recompressed to 16-235. Why not leave that untouched if the driver is set to output limited RGB? I am no programmer so I don't know if this is technically possible. But wouldn't that be the best solution?

Regards!
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#19
(2013-12-05, 16:49)FernetMenta Wrote: FireMan, you are completely immune to what developers say, aren't you?
Only when they're saying something that I know it's not the best option to me. For instance, I fully agree with your post and fully agree with Ned Scott. But not with fritsch's post...
Anyway, thanks for care about me.

Cheers.
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#20
(2013-12-05, 16:50)donkamillo Wrote: I can leave it in the xorg.conf because it gives me exactly the result I need. But it took me a while because I am no linux expert. So an option to set it up from the XBMC GUI would be nice.

There is another thing I don't understand. So XBMC outputs full RGB. As far as I understand it, my limited range videos are expandet to 0-255 and than recompressed to 16-235. Why not leave that untouched if the driver is set to output limited RGB? I am no programmer so I don't know if this is technically possible. But wouldn't that be the best solution?

Regards!

Your videos are in YUV format and computer graphics operate in RGB, that's a given. Hence those have to be converted from YUV to RGB. Doing this by software decoders (or some hw decoders like vdpau) we can convert YUV limited range to RGB limited range. Nevertheless OpenGL only knows full color range. So when converting to limited range and you set driver to limited as well, it would compress the limited range output which in this case is wrong.
Once YUV was converted to full range, the head/foot room is lost, regardless of the setting of the driver.

EDIT: I am not saying that setting driver to limited rage is wrong. But in this case XBMC must not be set to limited range.
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#21
(2013-12-05, 17:06)FernetMenta Wrote:
(2013-12-05, 16:50)donkamillo Wrote: I can leave it in the xorg.conf because it gives me exactly the result I need. But it took me a while because I am no linux expert. So an option to set it up from the XBMC GUI would be nice.

There is another thing I don't understand. So XBMC outputs full RGB. As far as I understand it, my limited range videos are expandet to 0-255 and than recompressed to 16-235. Why not leave that untouched if the driver is set to output limited RGB? I am no programmer so I don't know if this is technically possible. But wouldn't that be the best solution?

Regards!

Your videos are in YUV format and computer graphics operate in RGB, that's a given. Hence those have to be converted from YUV to RGB. Doing this by software decoders (or some hw decoders like vdpau) we can convert YUV limited range to RGB limited range. Nevertheless OpenGL only knows full color range. So when converting to limited range and you set driver to limited as well, it would compress the limited range output which in this case is wrong.
Once YUV was converted to full range, the head/foot room is lost, regardless of the setting of the driver.

EDIT: I am not saying that setting driver to limited rage is wrong. But in this case XBMC must not be set to limited range.
Ok. I got it. Can't be redundant limited.
Will try a night build to compare the results, limiting by driver versus limiting by player. Do you know if these two options will handle a similar quality to a TV?
Cheers.
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#22
Using XBMC's limited range option preserves btb and wtw if not using a hw decoder which internally converts to full range. There are some issues left with the XBMC option, i.e. black bars which currently are drawn with black level 0 (though this can be overridden by advanced settings). If yo play a video with aspect ratio different to the TV screen and which has black bars itself, you see different black levels.

To summarize:
The strategy of having limited rage option in XBMC is better than setting it in the driver but there are issues left to solve.
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#23
(2013-12-05, 17:06)FernetMenta Wrote: Your videos are in YUV format and computer graphics operate in RGB, that's a given. Hence those have to be converted from YUV to RGB. Doing this by software decoders (or some hw decoders like vdpau) we can convert YUV limited range to RGB limited range. Nevertheless OpenGL only knows full color range. So when converting to limited range and you set driver to limited as well, it would compress the limited range output which in this case is wrong.
Once YUV was converted to full range, the head/foot room is lost, regardless of the setting of the driver.

I am a little bit confused right now, but that might be because I did not understand everything. My english is not so good.

What I did understand is that I should leave the driver in full RGB and XBMC as well. When we are talking about the driver, are we talking about the xorg.conf, or something else? I did not change anything in the NVidia Settings. I just added an option-line in the xorg.conf.

Until recently I didn't have such a line and my videos looked bad. At least they didn't look as they do on other players. So if XBMC already does the converting and compressing or what ever correctly, why do my videos look as they should, after I added the option colorrange line in the xorg.conf? Without the line black clothing, a dark blue sky or such things don't look good.

I played a movie on my Dreambox 8000 and paused it, did the same thing on my XBMC machine and switched between them both. The difference without the colorrange line was huge. With the line they both looked the same. From what I see here, if XBMC is connected to a TV such a line seams to be nessesary.

I am running XBMC with Ubuntu 12.10 on an Zotac ION2 board and connected it via HDMI through a Denon AVR-1910 to a Philips 42PFL7606.

Regards!
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#24
I did some more testeng. It seams that in this case my AV-Receiver could be the problem. Setting the Colorrange to full and connecting the HDMI cable directly to the TV results in a perfectly nice picture. Colors and black levels look fine. Connecting the HDMI cable to the AV-Receiver results in bad black levels. So it looks like my Denon AVR-1910 cannot handle full range RGB. There is no option in the AVRs menues to control the color space or color range. I leave the ColorRange option in the xorg.conf, without it movies look terrible.

Regards!

Edit: Now I begin to understand why there is not much more complaining about this. Looks like I should upgrade to a newer AVR. :-)
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#25
I had this problem on my old Onkyo 605. I upgraded to a 414 this week and have the same problem even on the latest firmware.
I'm just going set everything up on limited colorspace.
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#26
I don't know about the Onkyos, because I use Denon for ages! And after long searches on the net I found out, that the Denon AVR-1910 passes fullrange RGB through only if it is connected to a DVI display. What ever that means. I'm thinking to upgrade to a Denon AVR-X4000 where it seams to be possible to select between movie, 16-235 and gaming, 0-255. That is what I read in several forums.

Regards!
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#27
(2013-12-06, 00:52)donkamillo Wrote: Edit: Now I begin to understand why there is not much more complaining about this. Looks like I should upgrade to a newer AVR. :-)

Yep, I found the same thing. Ordered the new Marantz receiver. Says it has passthrough. Hope they weren't FOS...will find out Tuesday.
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#28
I ordered my Denon AVR-X4000. Will see if it does work with full range RGB. If not, well I Purcase it because of the Audyssey MultiEQ XT32. Thats the main reason.

Regards!
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#29
I've dumped the Onkyo because it won't pass 3D either. Got a Sony yesterday to try tonight.
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#30
Are you sure the problem is in the Onkyo? On my 875 (which is 5 or 6 years old) There is a "Through" mode on HDMI monitoring which should pass the signal unchanged. Other modes such as "Auto" or 576, 720, 1080 etc can modify or upscale low-definition sources such as an older standard DVD player.
In "Through" mode the full range of RGB is passed through to my TV without any crushing of the blacks. This is at 1920x1080 @50p
In "Auto" mode the Onkyo seems to pass an interlaced signal to my TV, so I don't use that.
Odroid N2+ and Venz V10Pro (S905X), Sony DN1080 AVR, Samsung 49" LCD, Monitor Audio Bronze 5.1 speakers
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