The VideoLAN Forums

I have an AIW Radeon 8500. Despite its age, it's still a great card and I really like watching TV on my computer. Is VLC a viable app for TV watching? Every other application I tried had some kind of deal-breaking problem. Only the ATI MMC app does what I need, but it has major stability issues.

VLC recognizes my card with no problems, I can get VLC to display the TV picture well enough, and I can even stream it. But when watching the video locally it is always interlaced. Whenever I select any of the deinterlace options from Video>Deinterlace, the video disappears completely but the sound keeps playing. (Also, all the menu items except "Video Track" disappear from the Video menu when this happens.) This behavior occurs on both 0.8.6f as well as the latest nightly build, which I just tried. I rememeber it has happpened at least as far back as 0.8.1.

This is the command I'm using to launch VLC: If I set :dshow-size="720x240" (which I guess is equivalent to "discard" deinterlacing?) I no longer see combing but the video quality is noticeably reduced.

What's going on? Why can't VLC deinterlace video from my TV tuner?

Have you tried starting the stream with deinterlacing enabled? For example add to your commandline: Arite.

Thanks for the reply, Arite.
This gives me the same result as selecting a deinterlace option from the menu. That is:

-VLC starts with no errors
-Sound from the selected TV channel is heard
-There is no video.
-No options under the "Video" menu except "Video Track", which expands to a submenu with "Disable" and "Track 1", with "Track 1" selected.

What happens if, when the video is playing with deiterlacing and no video, you go to "Video >> Video Track >> Disable" and then back to "Video >> Video Track >> Track 1" (i.e. disabling then re-enabling the video track)?

Arite.

Absolutely nothing. I've tried that before.

Has anyone had any luck with this? I am experiencing the same problem.

Do you have the same issues if you save to file and then do a playback. MPEG 2 with MPEG 2 audio in a MPEG PS container would probably be best.

if you select a file and then do same procedure it works... but as i had no interlaced file ready at hand i guess its hard to judge. Does this problem arise at older vlc versions too?

same problem here


"Hi


I stream my desktop using a usb frame grabber.

Problem: the video is interlaced

Solution: deinterlace video

Problem: When deinterlacing the directshow device my vlc stops displaying the video


What i tried:

Open the dshow device, displays fine
Then: video, deinterlace... result is no video

"

p.s. this is not working in 0.9.4 nightlies either

someone can submit a bug??

I have met the same bug up till current v1.1 version (since the first day I started playing with vlc 0.8 versions). Seems that the directshow (analog tv) function of vlc windows version has not been well maintained/tested, maybe due to the unavailability of tuners to the developers.

But to me, the deinterlace bug is also really a pain in the neck, despite almost perfectness of other features of vlc.
I have observerd behaviour of this bug for a while. The findings are:
1. Somehow deinterlace breaks when sourcing from dshow:// interface (i.e., analog TV tuner/capture card, etc.), audio is there, video gone, no matter --video-filter or --vout-filter is applied. It doesn't matter whether the source channel (of dshow crossbar) is set to tuner(RF) input or any Composite/Svideo input pin.
2. Very strangely, if streaming and transcoding is used together with "...,deinterlace}" in the transcoding's parameters, the result is good, meaning vlc is really deinterlacing on the fly...
3. When playing back local files or streaming from network, deinterlace filter also work well.

So if you see people asking help on deinterlace problem, please,please carefully read the description point 1,2,3 here first before asking them to try various fixes, because most probably those won't work.

Could some directshow (dshow://) developer(s) in the videolan look seriously into this bug? it is pretty much the last bug preventing my friends and me to dump other directshow softwares...

BTW, I am a rookie who dun know how to submit bug reports.Maybe someone can do it for us.

To duplicate this problem, just buy off-the-shelf either a pure-analog TV tuner card (PCI/USB) or hybrid tuner. Set deinterlace filter to have a certain algo (e.g., linear or bob), set VLC 's video filter to have deinterlace turned on or off, and save preference and try "open capture device"(Ctrl + C), which triggers dshow:// settings to show...

If deinterlace is turned on, the video window flashes for a second and then disappears.

For many cards, you might want to further click "Advanced options...", and check/enalbe "Device properties" and "Tuner properties" in the dialog box that shows thereafter.

Looks like a sticky bug. It seems that with dshow (analog TV tuner) function, most vout-filters or video-filters cann't be used, which often triggers the vlc to show nothing. However, with transcoding, these filters can be used before the video is actually encoded.

Any plan to duplicate/fix such bug?

i run into the exact same problem - the video is displayed interlaced but everything works - activating deinterlace results in a black window.
I think i should mention that my tv-card delivers PROGRESSIVE data hence the interlaced picture is kinda ... weird - there seems to be a major bug in the way VLC handles directshow, it even adds scanlines!
I am willing to test / debug anything for developers who want to take a look at it - ill even submit a bug if someone points me to the correct destination (where should i submit?)

while this may need to be moved to the Windows-specific forum to receive the attention it needs (if indeed DirectShow is the issue here) i just wanted to add my input.

Using a USB capture device (Syntek STK 1160 aka EasyCap 60) i have NO issues with the deinterlace filters on current v1.1.4 release. log shows directshow access module and with deinterlacing turned on, the correct sequence (I420 etc.->deinterlace) being fed into VLC.

it might be interesting to note whether those having issues have cards that 'fake' progressive, whereby it feeds false info to directshow-- telling decoders to decode as if progressive. i would imagine the deinterlace filters would ignore this and apply algos no matter what, but if filter chain expects I420 or whatever and it believes it's being fed progressive or hybrid frames...

either way, maybe running the v1.1.4 (try the portable versions available on the interweb if you desire concurrent installs) may fix your problem as i don't know whether the problem was ever TRAC'd and fix was released.

oh and YAY!!! my VLC forum cherry is popped!

it might be interesting to note whether those having issues have cards that 'fake' progressive

very unlikely because it happens with 3 different (!) tv-cards here :

• Hauppauge WinTV PVR 150
• Leadtek Winfast TV2000XP Global
• Terratec Cinergy HT-PCI

the first one uses hardware-encoding - which is optionally bypassable by any application. I am living in germany hence my tv-signal is definitely progressive, PAL-B.

either way, maybe running the v1.1.4

i am always using the newest version of VLC ... 1.0.0 had many bugs so ... yeah

To change direction slightly, have you tried DSCALER ? I have an ancient BT878 card which no other application handles properly but DSCALER works perfectly.

To change direction slightly, have you tried DSCALER ?

yes. Same effect - i am forced to use the apps which are delivered with the cards, these show absolutely no interlacing, in fact the image is slighty better with them, no matter what alternative app i use