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| Jam One |
| Posted: Jul 6 2010, 12:40 PM |
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Advanced Member
Group: Members
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Joined: 8-May 09
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What is the best way - apart from using Avisynth - to perform an RGB <--> YUV conversion with certain matrix coefficients applied? Like "BT-709" and "PC-709", for instance?
I have HD video in MOV container (yes, it's from VDSLR) which I believe to be incorrectly converted by DirectShow decoders from YV12 to RGB32 in a manner as if it was BT.601
And I believe the video must be BT.709.
So I want to do a conversion back to YUV with 709 matrix. And... and I would like to have the way to do it solely in VirtualDub, without Avisynth.
Thank you in advance! |
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| phaeron |
| Posted: Jul 7 2010, 05:47 AM |
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Virtualdub Developer
Group: Administrator
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Joined: 30-July 02
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You can do these specific conversions in the experimental 1.9.X version in the testing forum, if you set the input format to YV12 and then use the alias format filter to switch it to full scale / BT.709.
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| Jam One |
| Posted: Jul 8 2010, 05:16 PM |
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Advanced Member
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...Hmmmm...
Changing the decompression format / input color depth does not seem to make any changes at all...
Images look quite different after "decompression format+alias format" adjustment, compared to the result of Avisynth's "ConvertToYUY2(matrix="rec709"/"pc.709") command.
Setting the "Alias format" seems, from my point of view, to be the analogy to "Assign color profile" command in Photoshop. While the "Convert to color profile" analogy is what is needed in this case, I presume.
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| phaeron |
| Posted: Jul 9 2010, 04:58 AM |
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Virtualdub Developer
Group: Administrator
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The alias filter doesn't actually change any of the data; as you noticed, it only retags it. That does, however, affect any further conversions that occur.
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| Jam One |
| Posted: Jul 9 2010, 12:43 PM |
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Advanced Member
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Posts: 580
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Well, thank you.
...I'm really ought to do more studies in this regard...
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Some people say the Canon's VDSLRs output BT.601 [0-255], but I don't believe this. For now.
Yep, I do believe it's [0-255]. I don't believe it's BT.601. Most of the headers mention BT.709, and only one header refers to 'BT.601 525 NTSC', which I believe is related to the conversion to standard definition.
Color primaries : BT.709-5, BT.1361, IEC 61966-2-4, SMPTE RP177
Transfer characteristics : BT.709-5, BT.1361
Matrix coefficients : BT.601-6 525, BT.1358 525, BT.1700 NTSC, SMPTE 170M
...Maybe I'm just a lamer...
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