USB capture device - can't adjust proc amp

[ChibiBoi]

I recently just got a VC500 because jagabo helped me realize my old USB capture device, the StarTech SVID2USB2, might contain an automatic gain control, which may have been causing crushed blacks. So I went ahead and bought the Diamond VC500 because I had read it didn't contain an automatic gain control. Well I tested it out and I found something interesting: The video was in black and white!!

I looked up the capture filter's proc amp using VirtualVCR and VirtualDub, and all I could adjust was brightness and contrast. All other settings were disabled and I couldn't adjust them.

The curious thing is, when I use EzGrabber, the program that was included in the installation CD, the video is really desaturated (almost black and white) and the hue is off. But the funny thing is, the program actually allows me to adjust the saturation and hue to bring it back to normal!!

So I guess my question is: how come EzGrabber can adjust these settings which I can't adjust in VirtualVCR or VirtualDub? And how can I fix it so they ARE adjustable? I really don't like EzGrabber's quality because it's really blurry and I also can't encode my capture with a lossless format.

Also, maybe if there is a fix to this proc amp issue, then I can also fix the proc amp with StarTech SVID2USB2 which would only let me adjust brightness, contrast, saturation, hue, and sharpness (maybe I can fix the crushed blacks if I could adjust the gamma or white balance??)

[usually_quiet]

I recently just got a VC500 because jagabo helped me realize my old USB capture device, the StarTech SVID2USB2, might contain an automatic gain control, which may have been causing crushed blacks. So I went ahead and bought the Diamond VC500 because I had read it didn't contain an automatic gain control. Well I tested it out and I found something interesting: The video was in black and white!!

I looked up the capture filter's proc amp using VirtualVCR and VirtualDub, and all I could adjust was brightness and contrast. All other settings were disabled and I couldn't adjust them.

The curious thing is, when I use EzGrabber, the program that was included in the installation CD, the video is really desaturated (almost black and white) and the hue is off. But the funny thing is, the program actually allows me to adjust the saturation and hue to bring it back to normal!!

So I guess my question is: how come EzGrabber can adjust these settings which I can't adjust in VirtualVCR or VirtualDub? And how can I fix it so they ARE adjustable? I really don't like EzGrabber's quality because it's really blurry and I also can't encode my capture with a lossless format.

Also, maybe if there is a fix to this proc amp issue, then I can also fix the proc amp with StarTech SVID2USB2 which would only let me adjust brightness, contrast, saturation, hue, and sharpness (maybe I can fix the crushed blacks if I could adjust the gamma or white balance??)

Most capture devices have an ACG, even if they don't advertise that they do. However, the AGC works better in some of them than in others, although I haven't read that the SVID2USB2's gain control is problematic. If there is a way to turn off AGC, you will have to examine the drivers to find it. Building a capture graph GraphStudio or GraphEdit will give you access to the driver's Direct Show controls so you can see what is possible.

Here is a general description of how you might proceed using GraphStudio:

The graph is built from left to right by adding filters and dragging an dropping with a mouse to connect "pins" (little nubs on the filter) to build the graph. One adds filters by clicking clicking "Graph" on the Menu Bar, then clicking "Insert Filters". This brings up the Filters window, and filters can be selected using the left-most dropdown list in the "Filters" window. Choosing all the right filters and connecting them often requires some trial and error, as does configuring the settings for the filters themselves. GraphStudio can sometimes add a missing piece between filters to make a connection work.

The first filter in the graph is the crossbar filter for the capture device, found under "WDM Streaming Crossbar Device". The second filter, also for the capture device, is found under "WDM Streaming Capture Devices."

The next filters to add are the video and audio encoders which might be listed under "Video Compressors" and "Audio Compressors" or "DirectShow Filters".

Next comes the muxer for the audio and video. Look for them under "DirectShow Filters". You probably want "AVI Mux"

Last comes a "Dump" filter or "File Writer" filter. A muxer may only work with a some of them, and you may need to experiment to find it.

Available settings can be accessed by right-clicking on a component in the graph and then clicking "properties"

Once the graph is finished, and the options provided for the filters in the chain are set up, a user can click on the green arrow icon in the tool bar to start the capture. Clicking on the red square icon on the toolbar stops the capture.

[jagabo]

Yes, try GraphStudio. You don't even have to build a full graph. Just add the capture driver or crossbar driver, right click on the filter then select Properties. Look for the Proc amp settings. If they're all available, start VirtualDub's capture module. Adjust the proc amp settings in GraphStudio. Do you see the picture in VirtualDub changing?

[ChibiBoi]

Yes, try GraphStudio. You don't even have to build a full graph. Just add the capture driver or crossbar driver, right click on the filter then select Properties. Look for the Proc amp settings. If they're all available, start VirtualDub's capture module. Adjust the proc amp settings in GraphStudio. Do you see the picture in VirtualDub changing?

Yes the picture changes when I open it with VirtualDub, VirtualVCR, and EzGrabber, but only the brightness and contrast options are adjustable

[jagabo]

Yes the picture changes when I open it with VirtualDub, VirtualVCR, and EzGrabber, but only the brightness and contrast options are adjustable

You're adjusting the proc amp in GraphStudio? And the other controls don't work in GraphStudio?

[ChibiBoi]

Yes the picture changes when I open it with VirtualDub, VirtualVCR, and EzGrabber, but only the brightness and contrast options are adjustable

You're adjusting the proc amp in GraphStudio? And the other controls don't work in GraphStudio?

Yes, the pro amp options that are available in GraphStudio are just brightness and contrast. The only program that I've used so far that allows me to adjust saturation and hue and sharpness is EzGrabber, so I don't understand how it's accessing those features.

[jagabo]

But there's a little color in what you're capturing with VirtualDub? I wonder if EzGrabber has a secondary software proc amp that lets you adjust those colors? If that's the case, you can use VirtualDub's HSV filter while capturing. Can you upload a short sample from VirtualDub?

[ChibiBoi]

But there's a little color in what you're capturing with VirtualDub? I wonder if EzGrabber has a secondary software proc amp that lets you adjust those colors? If that's the case, you can use VirtualDub's HSV filter while capturing. Can you upload a short sample from VirtualDub?

No, VirtualDub and VirtualVCR has absolutely zero color. But EzGrabber has a little bit of color at it's default settings.

VirtualDub, VirtualVCR, and GraphStudio seem to all share the same proc amp (zero color, can adjust only brightness and contrast) meanwhile EzGrabber has its own proc amp which can adjust everything else. It seems that when I use GraphStudio's proc amp, it adjusts EzGraber's image to black and white. But EzGrabber at it's default settings has a little bit of color.

[usually_quiet]

All of the software you tried uses the same WDM device drivers. You use the drivers' own GUI to access the proc amp controls in VirtualDub, VirtualVCR, and GraphStudio. Maybe the GUI provided in the drivers for theVC500's proc amp controls was poorly written, but API calls to the WDM drivers from within EzGrabber work correctly.

[ChibiBoi]

All of the software you tried uses the same WDM device drivers. You use the drivers' own GUI to access the proc amp controls in VirtualDub, VirtualVCR, and GraphStudio. Maybe the GUI provided in the drivers for theVC500's proc amp controls was poorly written, but API calls to the WDM drivers from within EzGrabber work correctly.

Is there a way to troubleshoot the problems and find out why it works properly for EzGrabber and not for anything else? I called their technical support line but they just told me they didn't know.

[vhelp]

i wrote a custom utility to call up the pro amp controls so i can make quick realtime adjustments to levels during video capture. it basically calls the same pro amp controls that virtualdub calls. i use it in conjunction with another utility i wrote to display the color under the mouse as i move it around inside the capture window so i can make realtime adjustments to aproximate 16..235 levels, comes in real handy.

but i suspect that the ezgrabber is customized with its own pro amps because you say the controls don't exist in the other (standard) pro amps..i.e., virtualdubs. do the controls look exactly the same or are they different ?

post a screenshot of both pro amp controls, the one from ezgrabber and virtualdub.

[jagabo]

I'm out of ideas.

[vhelp]

here are a few examples of my pro amp controls
on my ati600 and pinnacle studio av/dv, some of the pro amps are greyed out, while on my ads videoxpress, they are active, but non-functional.

if your ezgrabber pro amp control looks different, it might be a custom control in that software only.

also, on my winfast pci i/o card, it has the same functions as the videoxpress, plus the ColorEnable[x] is active and works, is a saturation booster.


* ati tv wondor 600 (aka, ati-600)


* ads instant videoxpress

[Brad]

Just a thought: make sure you've selected UYVY as the pixel format and that your computer is configured to properly display that format. For some reason the driver doesn't allow the more popular YUY2.

[ChibiBoi]

Just a thought: make sure you've selected UYVY as the pixel format and that your computer is configured to properly display that format. For some reason the driver doesn't allow the more popular YUY2.

Yes that was the format, but anyway, I returned the product, so I'm just going to have to deal with my other USB capture device since it allows color and I found a way to deal with the weird AGC (at least for the most part)

[jagabo]

I found a way to deal with the weird AGC (at least for the most part)

Was that with your DVD recorder passthrough?

[ChibiBoi]

I found a way to deal with the weird AGC (at least for the most part)

Was that with your DVD recorder passthrough?

Yes, by using the ES-15 to lighten the black level, and then bringing it down through the proc amp using the brightness and contrast controls. However, sometimes during the brighter scenes, the agc acts up