Crunchie and encoding resolution problem

[ziphnor]

I use MCE with 28" CRT connected via VGA->SCART, running at a desktop resolution of 720x576(PAL) *interlaced*(using powerstrip). I use Weave deinterlacing to get the proper field line-up on my TV. For this to work, its kind of important that my video files recorded from PAL TV(576 lines) still are 576 lines interlaced *after* being encoding, as i otherwise will get some weird artifacts i suspect. Can i set Crunchie to output 720x576 interlaced encoded files somehow? Right now it seems to be deciding on 640x480.

If not, would i be better of also letting Crunchie de-interlace the files, so i to avoid field alignment problems afterwards?

[arkay]

Hiya Ziphnor,

Two problems there.

1. divx/xvid have always been progressive only formats. Koepi did at one time I think introduce interlaced abilities into xvid but I don't think they ever worked too well. As such myself and the rest of the encoding world have always converted any material to progressive before converting to xvid.

2. You can certainly change the output resolution. There's an ini file in the install directory that has the output sizes for 4:3 and 16:9 material. Feel free to experiment. They must be divisible by 16 however!

It shouldn't really matter if the output is interlaced or not even though you're sending an interlaced signal to the set. Anything progressive has to be re-interlaced for an interlaced display anyway.

It also shouldn't matter what resolution they are, 640x480 has to be scaled up to 720x576 for you display anyway.

I understand where you're coming from in that you have you display set to display True interlaced material and will get the best results with the exact format the TV is capable of but your video card will convert any signal you throw at it to the correct signal for the TV also. Just that you will most likely get the odd bit of jitter etc...

Have you tried it with a normally encoded file? If you use the double rate deinterlace it should work well for your setup.

Cheers,
Arkay.

[ziphnor]

It shouldn't really matter if the output is interlaced or not even though you're sending an interlaced signal to the set. Anything progressive has to be re-interlaced for an interlaced display anyway.

Yes, but the captured video is interlaced and so is my output. If i use weave with the correct frequency i get an image with no (de)interlacing artifacts.

It also shouldn't matter what resolution they are, 640x480 has to be scaled up to 720x576 for you display anyway.

But thats the thing, my TV card captures at 720x576(PAL), so the encoding is downscaling it, and then when viewed it will be upscaled again, which is silly. Or maybe MCE is recording/capturing at a wrong resolution?
Update: I played a dvr-ms file on another computer in WMP it says its 720x480?!? If thats correct, then no wonder things look worse in MCE compared to Media Portal....

If you use the double rate deinterlace it should work well for your setup.

That was also my guess, i guess ill try that, but i really would like to make sure there is no re-sizing going on.

[arkay]

Just set the output resolution that you want in the ini file.

Once thing you have to remember though is that 720x576 is a 4:3 resolution. Even widescreen images are broadcast within this 4:3 resolution.

Crunchie will crop the black bars above and below and re-scale the image to a proper 16:9 resolution. Technically speaking 640x480 out of crunchie has a higher vertical resolution than WS broadcast in a 720x576 frame.

Feel free to experiment with different values though. I'm sure you'll find one that suits your needs.

The other thing is that you cannot see ANY de-interlace artifacts from a double rate deinterlace. The output avi is progressive at 50fps (if using PAL), 60fps for NTSC. Each "field" of the interlaced frame is converted to a full frame and then played back at double the speed. It really is the ONLY true way to deinterlace material.

Give it a shot and see. Even at 640x480 I'm certain you'll be pleased with the results given the space saving.

Cheers,
Arkay.