YUY2 vs 24 bit RGB to SVCD

[leonid_makarovsky]

I'm trying to experiment capturing and creating SVCD. What I do is I capture in YUY2 No Recompression AVI 480x480 29.97fps (VirtualDub). Then in ULEAD studio I convert it to the custom MPEG2 480x480 2600kb/s which is SVCD format. When I view it on external DVD, the image is kind of blurry especially during the movements. If I pause, the image is ok though. The original AVI looks great.

If I capture in 24bit RGB Uncompressed 320x240, and then x-fer to MPEG2, the image is much better. The source avi resolution is lower, yet the image is much better. What am I doing wrong?

--Leonid

[alucard2050]

i can't answer your question but what iwould like to know is what power does your PC have behind it to capture RGB24. when i try it i drop frames like a madman.

[malducci]

From what I understand, YUV2 and RGB raw 24bit are how color space is related to each other. YUV2 compresses the color somewhat so the AVI file is a little bit smaller, but does not compress the pixels themselves. The color will be more accurate and not as washed out as other color spacing algorithams. Don't quote me on this as I'm not exactly 100% sure.

[Kdiddy]

The key sounds like ot me is in the bitrate and encoder. What bitrate are you able to capture at in both 480x480 and 352x240??..in any case, 2.6 mbps at 352x240 will show less blocks & blurred high movement scenes than 480x480 (Especially if encoded with TMPG or even Ulead). Also are you using CBR or VBR??..if VBR, how many passes??...I would either suggest using an xVCD resolution of 352x480 ooooor, getting your hands on a copy of CCE and using it for mpeg2.

[leonid_makarovsky]

>i can't answer your question but what iwould like to know is what power
>does your PC have behind it to capture RGB24. when i try it i drop
> frames like a madman.


I can't capture in RGB 24 bit at 480x480 'cause it also drops frames like a madman. Maximum I can do is 400x400 in 24 bit RGB. YUY2 is no problem at 704x480.

--Leonid

[leonid_makarovsky]

>From what I understand, YUV2 and RGB raw 24bit are how color space is

To be more accurate it's YUY2 not YUV2 if it makes a difference. Well, properties of the captured files are as follow:

For 704x480: 16 bit, 29.932 fps, 19915kb/s RRIcm

For 480 x 480, 4281 Frames, 29.971 Frames/Sec, 13650 KB/Sec, Unknown Format.

So it is not 24 bit, but 14 bit. Again, if I pause, the frame is clear as glass. During the movement it gives me blurry image.

--Leonid

[leonid_makarovsky]

>The key sounds like ot me is in the bitrate and encoder. What bitrate
>are you able to capture at in both 480x480 and 352x240??..in any case,
> 2.6 mbps at 352x240 will show less blocks & blurred high movement
>scenes than 480x480 (Especially if encoded with TMPG or even Ulead).
>Also are you using CBR or VBR??..if VBR, how many passes??...I would

Where in VirtualDub I can find a bitrate information and settings?

I'm not sure about passes... Could you explain me what it is or point me where to get the info. I'm relatively new to the business.

>either suggest using an xVCD resolution of 352x480 ooooor, getting

My card can capture directly in mpeg2 352x480.

> your hands on a copy of CCE and using it for mpeg2.

What is CCE?

BTW, I am still unsure I am doing the right thing. I actually can capture in 704x480 MPEG2. But if I convert it to SVCD, it's going to be 2 compression ('cause originally I capture in compressed file). If I capture to an uncompressed avi and then convert it to SVCD, it's a single compression hence the quality is *supposed* to be better. Right?

--Leonid

[Kdiddy]

No capture to AVI not mpeg2..do that with CCE (Cinema Craft Encoder), look at the How To guides to your left...I think they discuss using VBR in one of the guides I think

[Anonymous65]

Most , if not all capture cards capture analog video in 4:2:2 mode. This is the same as YUY2 color resolution. Capture at 24 bit is like taking a 16 bit image and upconverting it to 24 bit. You do not gain any quality, you just make the file bigger. However, some filters and encoders might need 24 bit color to work.

[malducci]

skittlesen-

I mainly capture to raw 24bit RGB because I have had problems with certain apps opening YUY2 avi's. Maybe its just me but I thought I have seen a difference.

Anways try using IUvcr to capture the AVI files. I capture 20megs a second at about 55% cpu resource. And I'm only running 1Ghz Athlon.

[Luis]

I have tested to encode to mpeg-2 (svcd) the same avi file (480x288 capture from Hi8 source) with Tmpgenc, ulead videostudio 6, pinnacle studio 7 and intervideo Winproducer. The only good result was obtained with tmpgenc. All the others show mpeg-2 artifacts in fast moving and dark scenes. So, try tmpgenc!

[t0nito]

I experienced the same thing, now I do my captures in 24bit RGB because I have noticed that when I am capturing in YUV2 it seems like each line is not in it's correct order. Like this:
Interlaced (odd-even)
1
2
3
4
5
6
...
With 24bit these lines are correct in YUV2 it looks sort of like this:
1
3
2
4
5
7
6
...
it looks like it's odd-odd-even-even therefor pictures look blurry, since svcd are in MPEG-2 the dvd player will display the fields incorrectly when you pause the image is clearer because (I think) the player in pause doensn't decode the interlaced field nature of the paused frame. Well I know that in my case this was the problem. From what I read I think it's exactly what is happening to you.

[leonid_makarovsky]

>capturing in YUV2 it seems like each line is not in it's correct order. Like this:

[snip]

>With 24bit these lines are correct in YUV2 it looks >sort of like this:
>1
>3
>2

That would explain it. BTW, I used Matrox Marvel G450 eTV for capturing. I doubt it is forced to capture in 4:2:2. If I capture in RGB UNCOMPRESSED 400x400, my CPU (Athlon 1.2GHz) usage is 95%. So this is the limitation. If it were just the size of the file, I think I could still pass the limitation.

--Leonid

[t0nito]

Try using picvideo mjpeg codec in 24 bit rgb. I capture full screen (PAL 768x576) in my celeron 466 MHz at quality 17 without any problems and rarely any frame drops. Before I tried it I had to capture only in yuv2 because of the processing power limitation.

[leonid_makarovsky]

>Try using picvideo mjpeg codec in 24 bit rgb. I capture full screen (PAL

I downloaded the codec.

>768x576) in my celeron 466 MHz at quality 17 without any problems and

Honestly I don't know how you do it. What capture card do you have? Mine is Matrox Marvel G450 eTV. I used 480x480 NTSC and I drop frames like crazy. If I go beyond 400x400 resolution in 24 bit RGB ANY CODEC, I start dropping frames.

I have AMD Athlon 1.2GHz, ABIT KT7A RAID

--Leonid

[sommersby]

I capture at 640x480 using picvideo, quality set at 18, using 24 bit rgb with very few dropped frames. I like the results better than capturing with huffuv which cannot capture in rgb mode.

[alfalfa]

ok, now that i read the rest of the replies... yes you are using a matrox but keep reading ....


leonid_makarovsky ... hmmmm I see RRIcm there. Are you using a Matrox capture card? If so and its a g400TV you're RGB captures will be better than a YUY2 format. The g400TV (and possibly other Matrox capture hardware - I dont have the others!) uses a Samsung video decoder chippie. The Samsung part unlike the popular Brooktree / Connexant chippies, can decode a TV PIC to RGB as YUV 4:4:4 - ie preserving the full colour resolution of the broadcast. The BT chips just 'upsample' the YUYV (essentially the same as YUY2) back to RGB so you dont get a better PIC. The Samsung is also capable of real YUV (4:4:4) but the Matrox drivers dont support it.

Bear in mind that when you run your video thru most codecs they only work with YUY2 (or some other half res colour format).

[leonid_makarovsky]

I have tested to encode to mpeg-2 (svcd) the same avi file (480x288 capture from Hi8 source) with Tmpgenc, ulead videostudio 6, pinnacle studio 7 and intervideo Winproducer. The only good result was obtained with tmpgenc. All the others show mpeg-2 artifacts in fast moving and dark scenes. So, try tmpgenc!

This is the fun part. I tried to convert the source AVI using TMPGenc yesterday. The source AVI was custom format: YUY2 No Recompression, 29.971 fps (NTSC), 480x480 resolution. What I got in mpeg2 was a blank screen with just a sound. This result is kind of weird. Transferring YUY2 No Recompression, 29.971 fps (NTSC), 704x480 resolution would give positive x-fering (at least I could see the picture). But on the TV screen final result would still produce those blurry image. I haven't played it on external DVD player yet.

--Leonid

[leonid_makarovsky]

>yes you are using a matrox but keep reading ....

Yes, I do

>you using a Matrox capture card? If so and its a >g400TV you're RGB captures will be better than a

Yes, I use Matrox but it's Marvel G450 eTV with software encoder.

>capture hardware - I dont have the others!) uses a >Samsung video decoder chippie. The Samsung part

It this chip also responsible for pass-through audio? (you plug an audio in and the audio out supposed to go the the sound card).

>unlike the popular Brooktree / Connexant chippies, >can decode a TV PIC to RGB as YUV 4:4:4 - ie >preserving the full colour resolution of the

I don't know exactly what these numbers mean but I'm gessing 4:4:4 means no compression at all. Correct me if I'm wrong (as I said I'm relatively new to this business).


>dont get a better PIC. The Samsung is also capable >of real YUV (4:4:4) but the Matrox drivers dont support it.

So if I shop for a new capture card does it mean I am better off getting the one with Samsung chipie rather than bt8 or smth?

--Leonid

[alfalfa]

No, it does video only. Audio is handled by a separate chip (if they do it the same as a G400TV and I suspect they do)

YUY2 means half colour resolution. Luminance (brightness) is preserved, but Chrominance (colour) is half rate - ie for every two lines of picture only one colour sample (ok, thats crudely put). People see high resolution in B&W so we dont tend to notice too much. The Samsung decoder chip is capable of doing each line has its brightness and colour information preserved completely.

Most capture cards are based on the Brooktree chip these days. Exceptions are ATI All In Wonders, Matrox (but they killed theirs off, seems the G550TV will never be), and probably a few other integrated video / capture cards and Nvidia's offering.

[leonid_makarovsky]

>Most capture cards are based on the Brooktree chip
> these days. Exceptions are ATI All In Wonders,
>Matrox (but they killed theirs off, seems the
>G550TV will never be), and probably a few other

Matrox killed their low end capture cards, but they still support their RT2500.

>integrated video / capture cards and Nvidia's

I'm looking into it.

Actually, could you e-mail me at leonid_makarovsky@yahoo.com. I have some questions about the capture cards which is off topic for this ADVANCED X-fer forum. Thanks.

--Leonid

[kinneera]

But on the TV screen final result would still produce those blurry image. I haven't played it on external DVD player yet.

How do you know it produces a blurry image on your TV if you haven't tested it on your external DVD player yet? Are you saying that you are using TV-out? If so, you probably aren't getting a very good representative image, since you have to get a fairly expensive, high quality scan converter to really get a good picture straight from your comp. Even the best SVCDs will still look fairly blurry if you watch them on a comp. monitor at a high resolution or through a cheap TV-out, which apparently drop alternating lines or use other poor solutions to accomplish computer display on a TV. Try burning it to disc and running it through your DVD player and see how blurry it looks, you might be pleasantly surprised.

[alfalfa]

well, now i've done some tests. Matrox G400TV Vs WinTV 647 (PAL stereo audio). Without a doubt, the Matrox kicks the WinTV's arse nomatter what format you capture in.

http://members.dingoblue.net.au/~alfalfa1/matrox.bmp
http://members.dingoblue.net.au/~alfalfa1/wintv.bmp

Both captures done concurrently on the same PC. The matrox was set to composite in and the comp video fed from the WinTV tuner via an aligator clip (so if anything it should be _worse_ than the WinTV). AVI produced with huffyuv, then converted to RGB24 bitmap and clipped using MS Paint.

[mickboss]

1- SVCD has MPEG-2 VIDEO --> YUV 4:2:0

2- Use VirtualDub

3- Use PREVIEW instead of Overlay IF YOU HAVE Brooktree CHIPSET
IF you do this THEN YOU CAN capture up to 720x480/576 with MIRO PCTV and other low price, Great quality cards! NO NEED MIRO DC10 or similar!!!!!

4- Capture with PICVIDEO or MORGAN M-JPEG CODEC in YUV
These CODECs have a very CPU LOW DEMAND + GREAT PICTURE +
LOW HDD SPACE!

5- NO NEED to capture to RGB! If you capture in RGB it will do the conversion again to YUV!

6- Don´t bother with 4:4:4 / 4:2:2 / 4:2:0 ... INSTEAD OF talking USE IT. I tryied everything and I compared so:

- Capture in YUV2 at 720x480/576 at 30/25 fps (preview mode if using brooktree chipsets with MIRO PCTV, ...) with M-JPEG codecs

- Use Cinemacraft to encode to SVCD

NOTE: I capture to RGB BECAUSE I use TMPGEnc and it doesn´t deal with YUV! Cinemacraft does but I don´t like this software...and I have to pay for it ;)

Celeron II 950@1200 MHz
MSI 815 EP RAID ATA 100
256 Mb PC 133 SDRAM CAS3@2
13.6 Gb MAXTOR ATA-66
20 Gb MAXTOR ATA-100
Miro PCTV PRO Bt848A
Abit Siluro GeForce 2 TV-Out
DVD-Rom ASUS 16x ATA-100
CD-R SONY 32x12x8
Windows XP PRO