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  1. Everything I say is false koberulz's Avatar
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    How good a PC am I going to need? I've got a desktop that was pretty high standard when I bought it seven years ago, and a laptop I picked up a year ago just to plug it into the TV via HDMI for watching online content or video files. I've been using the laptop with the BlackMagic for my HD captures. It'd be easier, given it sits in the room with the TV, so it'd be an easier setup. Plus if I'm running S-Video to the USB-Live2 I can run composite straight to the TV and watch the tapes as I'm capturing. Although I'm not sure what to do about the audio in that setup, or if it'll even handle multiple video outputs?

    Anything else I need to know at this point? The AVT-8710 seems to have some proc amp-type stuff built in, and all the recommended proc amps are NTSC-only anyway, so I'm not sure it's worth adding that to my process.
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  2. A seven year old PC is probably fine for SD capture.
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  3. Everything I say is false koberulz's Avatar
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    Well, I'd certainly hope so. Was really just wondering if I'd be able to get away with the laptop. It handles HD capture from the BlackMagic fine, so I'm thinking yes, but is there anything I'm not considering?
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  4. Everything I say is false koberulz's Avatar
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    Well, the USB-Live2 showed up today, so I figured I'd set it up, throw a tape in the VCR I've already got, and test it out. Followed this to capture with VirtualDub. It's pretty old, but the general theme of my research seems to be 'this is pretty old, but nothing's changed', so I figured it was, at the very least, a good starting point.

    Captured a 30-second sample. Audio is out by about a second right from the jump. Turning on the histogram, there's a touch of red to the left and a lot of red to the right, but it doesn't change based on what's displaying on the screen.

    I'm not sure it's supposed to be stationary, but I'm assuming the red areas are fixed with the proc amp controls on the AVT (which I don't have yet)? What do I do about the audio?
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  5. Don't use any audio compression while capturing. Be sure to use a fast video compression codec like huffyuv. Don't use high compression codecs like Divx, x264vfw, etc. Play with the Capture -> Sync... options until you find something that works for your device. Often "Do not resync..." works best. Whenever possible capture to a drive that's not your boot drive.

    In my experience you have to turn off Video Preview for the histogram to work properly. You can usually adjust the capture device's proc amp controls to get proper levels. How you get at it varies but somewhere on the Video menu you will have access to them (Levels, Crossbar, etc.). Unfortunately, using the proc amp control that way you don't have a live preview or histogram so you have to go back and forth between adjusting the proc amp and viewing the image/histogram. A better option that works with most capture devices is to use GraphStudio to adjust the proc amp while viewing the preview/histogram in VirtualDub. In GraphStudio insert the capture module or crossbar (or whatever module has the proc amp controls) to the graph. Then right click on the module in the graph and select Properties to access the proc amp controls. Adjusting the proc amp there should leave you with a live preview/historgram in VirtualDub.

    Note that having a little of the histogram in the red region may not be a problem, especially if you are going to filter the video later. And at the low end sometimes the intrusion into the red is caused only by the black borders at the left and right edges of the frame. You don't really care about those.
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  6. Everything I say is false koberulz's Avatar
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    Video is Lagarith, audio is uncompressed. I don't see a "Sync" option under "Capture". I'm using VirtualDub v 1.10.4. I'm not capturing to my boot drive.

    Changing video preview from overlay to preview got the histogram to work, although the video disappeared. Does "a little" mean temporally, vertically, or horizontally?
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    What should I be adjusting in GraphStudio? Brightness or contrast? Or both? It seems like I can change the brightness up or down without changing the amount of red on the left at all, but decreasing it does decrease the red on the right. It seems to really flare up when rewinding the tape.

    Is there a way to get video and audio to preview? Enabling audio preview results in the video preview going black.
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  7. Lagarith may be too slow, you may drop frames leading to A/V sync problems. Use huffyuv 2.1.1, it's much faster.

    Adjust brightness and contrast to get all the histogram out of the red. The two controls are usually not completely independent. They usually work as an offset (shifting the whole histogram left or right) and a gain (stretching/compressing the histogram from left to right). Check a variety of scenes before settling on final settings. Again, some tapes/decks will have very dark bars at the left and right, much darker than the main image. In that case you can let the histogram into the red at the left. I wouldn't worry about what happens to the histogram during FF/RW -- automatic gain controls in the VHS deck may go bonkers then.

    I don't know about video and audio preview. When I was using VirtualDub I usually didn't preview the audio, just checked to make sure levels were ok before I capped.
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  8. Everything I say is false koberulz's Avatar
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    Tried HuffYUV, same result. VDub reports zero dropped frames, and in any event it's a full second out immediately. I'd have thought dropped frames would cause less of an issue than that. The reason I was using Lagarith rather than HuffYUV is that the latter doesn't import into Premiere.

    Regardless of what I set brightness to, the red on the left doesn't really change. In that situation, I assume just dropping the brightness until there's less red on the right is the solution?

    Thing is, without any video or audio preview while the histogram is working, I can't tell where the issue is. There's a change of recording, with a lot of static, followed by a mostly-white title screen, then the histogram drops into the blue. But I can't tell if it's the static that's causing the issue, in which case it might be the same thing as fast-forwarding or rewinding, or whether it's the title screen, in which case it's a problem that needs fixing.

    And in either case, it goes away pretty quickly, so it's a pain to try and fiddle with. Not that it matters, as I have neither the Philips VCR nor the AVT, and it's just a junk tape.
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  9. Originally Posted by koberulz View Post
    Tried HuffYUV, same result. VDub reports zero dropped frames, and in any event it's a full second out immediately.
    Are you capturing audio with the capture device or with the computer's audio input? Always use the capture device's audio inputs. If you can't get audio to sync at the start (ie, your 1 second delay) you can always remux the audio with the correct delay later. If the audio gets progressively out of sync it's harder to fix.

    Originally Posted by koberulz View Post
    Regardless of what I set brightness to, the red on the left doesn't really change.
    Did you change the Contrast setting too?

    Originally Posted by koberulz View Post
    In that situation, I assume just dropping the brightness until there's less red on the right is the solution?
    You have no other choice.

    Originally Posted by koberulz View Post
    Thing is, without any video or audio preview while the histogram is working, I can't tell where the issue is. There's a change of recording, with a lot of static, followed by a mostly-white title screen, then the histogram drops into the blue. But I can't tell if it's the static that's causing the issue, in which case it might be the same thing as fast-forwarding or rewinding, or whether it's the title screen, in which case it's a problem that needs fixing.
    Pause the tape while preview is active, then switch to the histogram.

    In your title sample the wrestling at the very beginning looks about right. The brights are blown out when the video first syncs to the title sequence but by the end it has settled down to reasonable levels. Maybe not bright enough.

    And sorry, I said "Capture -> Sync..." earlier but it's "Capture -> Timing..."
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  10. Everything I say is false koberulz's Avatar
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    No, I was capturing via line in, as the guide says to. Changed it, and now I can get the video and the histogram to display at the same time, and audio preview works as well, although if I have that on it drops a ton of frames. And if I have the video set to 'preview' I can get both it and the histogram, but it disappears when I start a capture. Sync in that case looked okay. But if I set the video to 'overlay', freezing the histogram and making video visible during capture, it seems to get a tiny bit out of sync (attached a sample).

    Set it back to preview, to see if that was also slightly out of sync...and now it's just capturing audio.

    Still appears like the title screen is too bright, looking at this (also, I can't pause it because this VCR doesn't have that function)?
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  11. Sync2's audio is about 250 ms early. The darks look overly dark in that shot. They're not crushed though so maybe it's just that shot.

    Now the bad news: you really need a line TBC to straighten up all the vertical edges. Notice how crooked the post at the right in the background is:

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    And it changes with every field/frame. You could use an old Panasonic DVD recorder in passthrough mode for that. See this post for examples:
    https://forum.videohelp.com/threads/319420-Who-uses-a-DVD-recorder-as-a-line-TBC-and-what-do-you-use
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  12. Everything I say is false koberulz's Avatar
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    Originally Posted by jagabo View Post
    Sync2's audio is about 250 ms early.
    How can you tell? I mean, you say 'about', but it's still pretty specific.

    Regarding the line TBC: as I said, the only equipment that's arrive yet is the USB-Live2, so I'm taking the opportunity to run a junk tape through my existing VCR to wrap my head around the capture process. I've also ordered a Philips VCR (rebadged JVC, per digitalFAQ's buying guide) with line TBC, and an AVT-8710, but they're taking longer to get here.
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  13. Everything I say is false koberulz's Avatar
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    Just gave it a whirl on my new laptop, and the video preview just displays black, and it refuses to capture. If I use the included WinTV program, it lets me capture a .ts file just fine.

    Is there something I should have installed that I've missed, or something along those lines? I just dropped the 'VirtualDub' folder from my desktop onto a USB, then onto my laptop.
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  14. Originally Posted by koberulz View Post
    Originally Posted by jagabo View Post
    Sync2's audio is about 250 ms early.
    How can you tell? I mean, you say 'about', but it's still pretty specific.
    I played the clip with MPCHC and used it's audio delay/advance feature (+ and - keys on the numeric keypad) to shift the audio until it looked right.

    Don't know what's going on with your laptop. Is it running Windows 10? Maybe that's the problem.
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  15. Everything I say is false koberulz's Avatar
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    It is, but WinTV works fine.
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  16. A histogram like that indicates that the capture device is clipping blacker-than-black rather than capturing it, so you'll never see dark values in red (besides that sliver). I suppose this is typical with PAL captures, since a 0 IRE system doesn't have superblacks.

    To ensure no black crush, you'll need to raise the Brightness until it's obvious nothing is being lost at all (there should be a larger gap to the left) and then gradually lower it.
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  17. Originally Posted by vaporeon800 View Post
    A histogram like that indicates that the capture device is clipping blacker-than-black
    Yes, but after looking at the actual caps I decided it was mostly in the black borders and oversharpening halos. And since there was no peak at the very left edge he probably can't adjust the proc amp to restore the darker parts. Maybe the AVT-8710 will help once he gets it.
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  18. Everything I say is false koberulz's Avatar
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    I'm confused. My initial thought was that it was the whites that were the problem, because that's generally what's on the right hand side of a histogram and that's where all the red is.

    Am I missing something?
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  19. Often a sharp drop at the left (dark) end of the histogram indicates some pixels should have been darker but they were "crushed". For example, the light blue in this image represents the left end of the histogram you might get from a video:

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    The dark blue indicates where darker pixels in the video should have fallen but some processing has crushed them up to that big peak in the light blue histogram. So if that big peak is at Y=16, something in the processing has caused values less than 16 to have the value 16.

    Note that the rec.601 spec defines Y=16 as as full black and there aren't supposed to be Y values less than that -- so some programs will automatically change pixels with Y below 16 to Y equals 16. That can also happen when video is converted to RGB (all values below Y=16 are converted to the same shade of RGB black, R=G=B=0) then back to YUV (Y=16).

    Similar effects can sometimes be seen at the right (bright) end of the historgram where Y=235 is defined as full white and values above that may be crushed.
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  20. If you're up for screwing around with GraphEdit and Avisynth, I find the waveform monitors available to be more useful than VirtualDub's histogram, and the incoming video won't disapear. In your graph, you may have to include the Conexant format converter that I mentioned.

    https://forum.videohelp.com/threads/360129-How-to-use-Avisynth-videoscopes-with-realtim...=1#post2279970
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  21. Yes, waveform monitors are much more useful. Here's an explanation of what a waveform graph is:

    https://forum.videohelp.com/threads/340804-colorspace-conversation-elaboration?p=212156...=1#post2121568

    The GraphEdit to AviSynth trick is worth a try but it doesn't work for some devices.

    AviSynth's Histogram() shows a waveform graph by default (the name is misleading) but it gives a vertical waveform graph at the right rather than the traditional horizontal waveform graph. The easiest way to get a horizontal graph is:

    Code:
    TurnRight().Histogram().TurnLeft()
    That gives a horizontal histogram above the image, like in the post above.
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  22. Everything I say is false koberulz's Avatar
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    Can you give more specific directions? I've gone into Graph Studio, added the Live2 as a filter, and saved the graph. Then an AVISynth script:
    DirectShowSource("graph.GRF")
    TurnRight().Histogram().TurnLeft()
    But I get an error if I try to open that in MPC, saying only 1 stream is supported for GRF files, one of Audio or Video must be disabled.

    And even if that worked, I'm not sure what the next step is? Leave it in MPC, fiddle with the proc amp settings in graph studio and MPC would update live? Or something else?
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  23. You need to connect all unused output pins to the Null Renderer. Leave just the video capture pin open. You can then open the AVS script in any program that opens AVS scripts. Media players, VirtualDub, etc.

    But first, make sure you have the right capture filter. Right click on the video capture pin and select Render Pin. Then press the play button in GraphEdit and verify you get a live picture. You may have to piece together more components like a crossbar filter.
    Last edited by jagabo; 24th Feb 2016 at 07:06.
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  24. Everything I say is false koberulz's Avatar
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    "Null Renderer"?
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  25. Yes, Null Renderer:

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  26. Everything I say is false koberulz's Avatar
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    Ah, righto. There's no "all" option for me, but I found it in the DirectShow Filters category. Still gives the error about only allowing one stream when I play the AVS, and when I do the render thing I just get a black window. Not sure what to do with the crossbar? I tried connecting it the only way it would seem to work, still getting the one-stream error and black render screen. Attached a screenshot of what I'm doing.
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  27. Configure the Crossbar or Capture (depends on device) filter to take input from the correct source (composite, s-video, etc.). You should then see the live picture when you play the graph. Before saving the graph for use in AviSynth remove the Video Renderer and (probably) the Conexant Color Format Converter. That leaves the video Capture pin available for DirectShowSource() to connect to.
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  28. I've never had to add Null Renderer. I think my solution was adding audio=false to DirectShowSource.
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  29. Everything I say is false koberulz's Avatar
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    The Capture only contains 'analog video in', the Crossbar appears to be set up correctly (the VCR I'm using right now doesn't have S-Video):
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  30. Everything I say is false koberulz's Avatar
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    Originally Posted by vaporeon800 View Post
    I've never had to add Null Renderer. I think my solution was adding audio=false to DirectShowSource.
    That just gets me an 'insufficient system resources exist to complete the requested service" error in MPC. And still a black render window, if I add that back in.
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