Component worse than S-Video on Betacam deck

[kernelfree]

I'm in the process of capturing footage from a Sony UVW-1400AP Betacam deck and I noticed that the component output (ypbpr) has color artifacts not showing on the s-video output. I tried swapping cables but without much improvement. Any guesses?


[Attachment 86696 - Click to enlarge]


[Attachment 86697 - Click to enlarge]

[dellsam34]

S-Video is actually worse but the alternating lines in the YPbPr sample could be due to the way the files are generated, we need to know the capture workflow for both samples hardware and software to be able to help you.

[kernelfree]

S-Video is actually worse but the alternating lines in the YPbPr sample could be due to the way the files are generated, we need to know the capture workflow for both samples hardware and software to be able to help you.

S-Video workflow: Hauppage USB Live2 + AmarecTV + HuffYUV encoding
Component workflow: Blackmagic intensity Extreme + Media Express + Apple prores 422 HQ encoding

I tried the component output on a LCD TV and I'm getting the same color artifacts.

[Sharc]

For the Component the pattern is in the U,V (Pb,Pr) planes. Something wrong with the subsampling or chroma placement?
Component field:

[Attachment 86702 - Click to enlarge]


S-Video field:

[Attachment 86703 - Click to enlarge]

Edit: For the Component the colors are pretty accurate (close to the nominal bar RGB) when one blurs the stripes.

Edit2: The stripes of the Component disappear when one converts the pixel format to YV12 (4:2:0) and the colors are accurate.

[Attachment 86704 - Click to enlarge]

[Attachment 86705 - Click to enlarge]

[dellsam34]

Component workflow: Blackmagic intensity Extreme + Media Express + Apple prores 422 HQ encoding

I tried the component output on a LCD TV and I'm getting the same color artifacts.

Use lossless AVI for just a test, Make sure you choose 625i50 PAL to avoid de-interlacing.

[Sharc]

It is PAL and the 'Component' output looks like Hanover Bars. If so, it is left to the decoder to suppress these.
https://en.wikipedia.org/wiki/Hanover_bars


[Attachment 86708 - Click to enlarge]


[Attachment 86709 - Click to enlarge]

Added:
You can "fix" it in post using Avisynth:

LWLibavVideoSource("ypbpr bars.mov")
AssumeTFF().separatefields().vinverse().weave()

[dellsam34]

That's why I asked for an AVI lossless sample instead of QT to see if it's a codec problem.

[kernelfree]

Here's a 10bit RGB Quicktime lossless capture. Note that on MacOS I am unable to select AVI lossless as an option.

[Sharc]

My conclusion is the same as in post#4 and #6.
It may be a decoder maladjustment issue. The service manual of the player may have some alignment hints/instructions. Or the capture process does not handle it properly. The flicker at the bottom is also suspicious.
I have no better explanation
Anyway, it seems to be "fixable" in post processing. Not sure what loss the 'vinverse()' will incur, but it should be little.....
If you plan YUV 4:2:0 as your final format you could convert the source upfront, loosing some color resolution of course.
Running out of ideas ......

[dellsam34]

That file is affected as well, If you don't have access to a PC to try lossless AVI or other capture software just capture via S-Video on Mac or apply one of the filters like the one provided above.

[kernelfree]

That file is affected as well, If you don't have access to a PC to try lossless AVI or other capture software just capture via S-Video on Mac or apply one of the filters like the one provided above.

I managed to convert it to 8 bit and 4:2:0 and got rid of the artifacts, it's a pity that I can't make full use of the component outputs. Since I see the same problem connecting it to a TV I think it's the deck's fault, hope to find someone that knows why and where to put hands. Thanks for now.

[Sharc]

I managed to convert it to 8 bit and 4:2:0 and got rid of the artifacts,....

Unless some component in the workflow requires it there is actually no need for reducing to 8bit. You can keep the 10 bits and downsample to 4:2:0, for example with

z_ConvertFormat(pixel_type="YUV420P10")