Analog sourced video on LCD monitors?

[ministry88]

As I was transferring another old VHS of mine to DVD-R I wondered how my DVD-Rs, which are my old VHS (which is an analog source) will look on non CRT displays. I put one of my DVD-Rs in my computer and watched the first few minutes on my LCD computer monitor and can't say I liked what I saw. It seemed the digital compression artifacts were really pumped up and any flaws in the original analog signal were pumped up too, along with a strange flickering of the brightness level.

All of the above uglies are either drastically reduced or not viewable at all on my old CRT TVs. I'm just wondering what the point is of transferring to DVD-R if the displays of the future (DLP Projectors, Plasma, LCD) will make my DVD-Rs look WORSE than the original VHS!

Do some computer monitors as well as some new plasma TVs and LCDs have certain filters or options for analog video sources so they don't worsen the analog picture?

[edDV]

You probably deinterlaced and over compressed when converting your tapes. Noisy source requires higher bit rate.

Do some computer monitors as well as some new plasma TVs and LCDs have certain filters or options for analog video sources so they don't worsen the analog picture?

Generally, the more expensive the HDTV (e.g. high end video processor), the better it does with SD video.

[ministry88]

Ed, I have a Pioneer DVR-340H DVD recorder that has a flex recording option that allows me to optimize the bitrate in 5 minute increments (instead of just the more restrictive XP, EP, SLP, and SP modes), so I doubt low bitrate is the problem. Also, how could I have deinterlaced the video? I use a JVC HR-S7600U SVHS VCR and use some of the filters most of the time, like the "soft" video option and have the TBC on for further DNR. But that wouldn't deinterlace the video, would it?

I have also heard the higher-end HDTVs have better upconverters. What I hope is in a few years when I have the $$ the upconversion technology will be much improved and cheaper. I think this will be the case as this is usually how it works out with new technology...

[ministry88]

Perhaps this is just some anomaly with my computer LCD monitor, or issue with the video card. I say this because I tried out a handful of my DVD-Rs at a store on various high-def displays and they looked GREAT -- dare I say EXACTLY as good as on an old CRT monitor!

Has anyone else had this flickering issue with an LCD monitor when viewing DVD-Rs?

[edDV]

Perhaps this is just some anomaly with my computer LCD monitor, or issue with the video card. I say this because I tried out a handful of my DVD-Rs at a store on various high-def displays and they looked GREAT -- dare I say EXACTLY as good as on an old CRT monitor!

Has anyone else had this flickering issue with an LCD monitor when viewing DVD-Rs?

Have you tried a different DVD player, or a DVD-R that was burned on the computer?

Describe the flicker. Is it all the time or just during motion?

[ministry88]

Ed, I've included a link to a quick (14s) video clip I just shot that documents this weird flicker. Again, it doesn't happen on any other display or player. Also, DVD-Rs made by other people with different setups don't flicker on my LCD.

*By the way, I just tried recording a VHS of mine on my DVD Recorder's SP setting and it seems to lessen or altogether remove the flicker! BUT, it's not like I was recording before in EP mode or something. I was using the flex setting that helps maximize the bitrate for (theoretically) the best video quality and least compression. But this setting seems to cause the flicker on the LCD monitor, or at least make it worse! This is the setting I used for the clip. I thought the flex setting was the best setting available, but now I don't know...

FYI: My setup is a JVC HR-S7600U SVHS VCR for playback, an AVT-8710 TBC, and a Pioneer DVR-340H DVD Recorder for recording.

Thanks for any help!

Clip: http://www.mediafire.com/?ungmbngnmmm[/url]

[edDV]

It shows severe compression errors probably from source noise. Hard to tell.

[lordsmurf]

Does that monitor try to actively re-calibrate color/contrast, maybe?

[ministry88]

All I know is, this is the only display that looks this bad. As I've said before, all my regular CRT TVs play the DVD-Rs cleanly. And I tried these same DVD-Rs in a store on various displays (LCD, Plasma, DLP front projectors) and they looked GREAT.

So perhaps it really is just something wrong with my computer monitor or computer itself. The only other thing it could be is my DVD Recorder, but I don't think that would make sense because if that WERE true, wouldn't the DVD-Rs look bad on ALL displays?

Smurf, I don't think my monitor tries to actively re-calibrate anything. Is there anything I can check to tell?

**For the hell of it, I've included the actual video file as an .mpg file. The first clip was just me filming the monitor with my digital camera. If anybody could tell me how the video file looks on their monitor vs. the first clip (I'm betting it will look MUCH better) that would be much appreciated!

Clip 2: http://www.mediafire.com/?zzommjznmzk

[jagabo]

The MPEG file looks ok -- in terms of flicker. All I see is the "normal" variation from frame to frame of a mediocre film to video transfer. The problem is in your media player or monitor.

Your levels are way off. I'd get a proc amp put it between your VHS deck and DVD recorder.

[lordsmurf]

No flicker here either.
The VHS tape is a poor transfer of the film, there's not much that can be done to it for improvement. If would consider cropping it to a 16:9, however, not a mattered 4:3

[ministry88]

Thanks guys! Jagabo and Smurf, did you watch the clip on an LCD computer monitor? I ask because I just came back from Best buy and tried out that clip and some of my other DVD-Rs on some of their computers. Sure enough, the flicker was there! BUT there was no flicker and a BEAUTIFUL picture on the apple LCD monitors, as well as some of the laptops (which also had LCD)! Go figure. I think the answer is the video card and the processing power of the computer and how well it can filter noise. Again, the DVD-Rs played flicker-free on ALL the LCD and plasma TVs.

*Jagabo: Thanks for the split-screen comparison shot. Is the darker pic on the right the one with the better black levels? I don't have a proc amp (and I'm not going to get one -- I don't want to get that involved as I have many more VHS to go and don't have the time/money), but my Pioneer DVD Recorder has a black level setting for either 0 IRE or 7.5 IRE. I have no idea which setting to use! I've left it on 0 IRE which does noticeably brighten the picture, and setting it to 7.5 IRE makes it darker and makes it look more like the pic on the right. Is this what I want for a more accurate picture? I'm using an NTSC display, by the way.

Thanks!

[jagabo]

did you watch the clip on an LCD computer monitor?

I watched it on three different computers all with different LCD monitors. There was nothing like the flicker in your MOV file.

*Jagabo: Thanks for the split-screen comparison shot. Is the darker pic on the right the one with the better black levels?

Yes. That's a night shot so the background should be dark.

my Pioneer DVD Recorder has a black level setting for either 0 IRE or 7.5 IRE. I have no idea which setting to use! I've left it on 0 IRE which does noticeably brighten the picture, and setting it to 7.5 IRE makes it darker and makes it look more like the pic on the right. Is this what I want for a more accurate picture? I'm using an NTSC display, by the way.

Yes, USA NTSC is IRE 7.5 so you should use that setting. (Japanese NTSC is IRE 0.) That won't fully fix the problem with that particular tape but it will be better.

[ministry88]

Jagabo - Thanks again for the prompt, informative reply!

*I agree the video clip looked overly bright and washed out, but couldn't I get the same results (that is, darker blacks) by just adjusting the TV's brightness controls? Or is the IRE setting more profound and expansive? I'm just wondering because switching to 7.5 IRE darkens the whole image. But then again, the 0 IRE setting makes it brighter and more washed out, although this can mostly be remedied by turning down the brightness.

I'm just wondering what is the "true" and "correct" setting.

[lordsmurf]

Yes, LCDs.

[ministry88]

Just wondered: how does a Japanese VHS play into the IRE level? Isn't Japanese NTSC 0 IRE? So wouldn't I want to set my Recorder to 0 IRE to match? On my Japanese VHS, it looks VERY dark at 7.5 IRE, with seemingly crushed blacks and very little shadow detail.

*To complicate the matter further, a lot of my Japan VHS are actually TRANSFERS done by a US company using the Panasonic AG1980. Does using US equipment CHANGE the IRE setting of the original Japanese VHS to the American NTSC IRE standard of 7.5?

Thanks!

[edDV]

Just wondered: how does a Japanese VHS play into the IRE level? Isn't Japanese NTSC 0 IRE? So wouldn't I want to set my Recorder to 0 IRE to match? On my Japanese VHS, it looks VERY dark at 7.5 IRE, with seemingly crushed blacks and very little shadow detail.

*To complicate the matter further, a lot of my Japan VHS are actually TRANSFERS done by a US company using the Panasonic AG1980. Does using US equipment CHANGE the IRE setting of the original Japanese VHS to the American NTSC IRE standard of 7.5?

Thanks!

A true Japanese VHS tape would show crushed blacks on a monitor adjusted for 7.5 IRE black.

Solution? Turn up monitor brightness 7.5 IRE.

Remember to turn it back for 7.5 IRE source.

[ministry88]

edDV - I was actually talking about what IRE level I should set my DVD RECORDER to when I transfer an original Japanese VHS. I'd assume I'd set it to 0 IRE to match the Japanese NTSC of 0 IRE, right?

And when I display that DVD-R, I'd have to turn the monitor's display to 0 IRE, right? Or at least play with the brightness to get it to display right.

[edDV]

edDV - I was actually talking about what IRE level I should set my DVD RECORDER to when I transfer an original Japanese VHS. I'd assume I'd set it to 0 IRE to match the Japanese NTSC of 0 IRE, right?

If you have a zero IRE setting, it should map 0 IRE to digital 16 instead of 32.

And when I display that DVD-R, I'd have to turn the monitor's display to 0 IRE, right? Or at least play with the brightness to get it to display right.

If it recorded black to digital 16 it should play like any other North American source.

[ministry88]

Wait - what is digital 16 and 32? Do I want a 0 IRE source to map to digital 16 and not 32? Or is it better to map to 32?

Basically, if the IRE isn't set properly, the blacks won't look accurate, right? They'd either be too dark or too bright, right? So I'd have to turn up/down my brightness levels on my playback display?

Thanks!

[edDV]

Wait - what is digital 16 and 32? Do I want a 0 IRE source to map to digital 16 and not 32? Or is it better to map to 32?

Basically, if the IRE isn't set properly, the blacks won't look accurate, right? They'd either be too dark or too bright, right? So I'd have to turn up/down my brightness levels on my playback display?

Thanks!

32 gives the famous Sony DV camcorder analog capture "washout".

Here is the tech summary for N.American capture devices.

Normal 7.5 IRE black video (e.g. your cable box) captures black to digital 16.

Japanese VHS has black at 0 IRE but the DVD recorder normally captures 7.5 IRE as black (digital 16) so everything below is crushed.

In some cases the sub black is not recorded (e.g. a clipped to 16-235) so the brightness setting on the monitor won't help.

Errors in the other direction assume black at 0 IRE (e.g. many Sony camcorders with analog pass through). When 7.5 IRE source is captured, the Sony camcorder assumes black is at 0 IRE and assigns analog 0 IRE to digital 16. This causes 7.5 IRE to map to 32 causing the washout.

DVD recorders are a mixed bag. Some have "black correction". You need to test what this does.

[jagabo]

When video is digitized the brightness of the picture (aka luma, or Y in the YUV system) is represented with an 8 bit unsigned integer. This means the value can vary from 0 (darkest) to 255 (brightest). By convention, the darkest darks in the picture should have a value of 16. The brightest brights should be at 235. When this video is displayed, pixels with luma below 16 may all appear the same shade of black, pixels above 235 may all appear the same brightness -- regardless of how you adjust the display device. That is, the device putting out the analog signal my clamp those pixels outside the valid 16-235 range. In fact, the device or software capturing the video may clamp it before storing the data. So all values below 16 will become 16 and all values above 235 will become 235. So details outside the 16-235 range may be lost forever.

In a North American NTSC analog signal the blacks are at a slightly higher level than in a Japanese NTSC analog signal. Hence the 0 and 7.5 IRE settings. If you capture a North American analog source at the wrong setting (IRE 0) the blacks will be ~32 instead of 16. This will leave the picture looking washed out when played back on properly calibrated equipment. If you capture Japanese NTSC video with the wrong setting (IRE 7.5) the blacks will be at 0 instead of 16. This will play back too dark on properly calibrated equipment.

In practice, VHS recordings and VCRs are often way out of whack. For best results a video processing amplifier should be used to adjust the analog levels before the video is captured.