Blocky Images when Playing back a VCD

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Why all of my recorded VCD images/pictures look blocky?

I'm using the Snazzi PCI card and Snazzi Amigo software made by Dazzle to capture the video and audio from a VHS source. This card encodes/decodes MPEG1 in hardware. I don't have any problem with the audio but the recorded video looks blocky when I played it back on my Sony DVP S7000. I live in the States so I used NTSC when recording. I used WINONCD software to make VCD. The VCD picture quality is worst the VHS (at least for my VCD).

How can I improve or get rid of the blocky images.

-- Anthony Tran (anthony_w_tran@yahoo.com), June 11, 1999

Answers

I got the same thing, but it doesn't sound as bad as yours. I also use the Snazzi and Amigo. After capture, the mpg isn't recognised (although I set it to produce a Video CD compatible MPEG-1 file) unless I put it thru Xing Encoder again before burning with Adaptec Easy CD (3.5b, I think).

A friend suggested I capture (via Snazzi) at a higher data rate (4 vs 1.15 with standard Video CD QIF standards) before I encode. I'll let U know when I've done it.

-- Daniel Long (lcheetec@yahoo.com), June 11, 1999.


Same problem here, but with the Dazzle Digital Video Creator. The picture quality gets blocky, esp. if there is a little noise (static) in the video. But I get about the same results with the LSX encoder on video captured to AVI. I get much better quality when I take the time to capture to AVI, then encode with Xing.

I tried using the High bitrate settings on the DazzleDVC and then re- encoding with Xing, but the marginal improvements didn't make up for all the lost time. (and I mean marginal)

But there are trade-offs with each approach. The color and some types of detail are more accurate with the Dazzle capture hardware, but it get blocky. Xing encoded files are a bit dark, requiring a lot of tinkering to compensate during the original capture process, but no blocks. LSX has more accurate color, but takes longer to encode. And LSX, even after serious tweaking, still yields slightly more blocky output then Xing.

If there was such a thing as an All-in-wonder128(currently vaporware), i'd be willing to give that a try, but for now the Dazzle is the best compromise for me.

-- Sean (sean@magnuminvestments.com), June 11, 1999.


I also have the Dazzle DVC, one thing I quickly found out is that the mpg files created by the DVC are not Whitebook standard mpeg1 files. I don't know why the morons that engineered the DVC didn't provide a whitebook compliant format, but they didn't (they even talk about this on the technical help section in their webpage). One thing I found out though, is that the NTI CD-Maker will let you add any valid mpeg1 file (even non-whitebook compliant ones) to a vcd. This means that even mpg files recorded at a higher bitrate/quality will be added to your vcd. I experimented with this, and I found out that my dvd player will play vcds with mpeg files recorded using the 'Movie Quality' mode, hence providing much better quality, and allowing me to transfer the newly created file as-is without any conversions. There is a limit on the quality you can use, though: After experimenting with several settings, I was able to determine that the highest I could go on the quality is 21,000 (anything higher will make my DVD player skip frames and freeze every few seconds...) It's important to say that this produces 'non-compliant vcds' and that they might not play correctly on other vcd or dvd players, but hey, they work perfectly fine for me.

-- Gil (gilg@whc.net), June 14, 1999.

Gil: What make and model is your DVD player?

The adaptec software chokes on a lot of otherwise good Mpeg files. It only seemed to accept files encoded with Xing. Upgrading to the 3.5C build from their website seems to have taken care of that.

The Ceqaudrat applications don't have a problem with the files the Dazzle puts out either, but they don't fully support my burner. If only there was a way to build the image files with videopak and burn with CDRWin. I tried a couple of hacks on the image files, but haven't gotten it to work yet.

Also there is a patch for the Dazzle software on their website that solved some of my problems. For example, crashes when trimming files.

-- Sean (sean@magnuminvestments.com), June 14, 1999.


I have an RCA DVD-5510, and my cd burner is a memorex CDR-1622. The only problem i've had, is that my computer does not seem to like both NTI CDMaker and Adaptec CD Creator installed at the same time. I need to remove (uninstall) one to install the other...

-- Gil (gilg@whc.net), June 14, 1999.


My NTI CD maker doesn't accept any MPEG1 files. The Adaptec works with Xing encoded mpegs but keeps putting it in the segment instead of the mpegav folder.

-- (jellyrol@sfsu.edu), June 17, 1999.

The blockiness is due to the quality produced by Snazzi. We experiment with all sorts of encoding hardware and we have to give Snazzi a thumbs down for professional mpeg editing. It is alright for average usage and the software bundle is fantastic but Snazzi generates a tremendous amount of blocks with fast moving scenes. You can improve the image with pre-filtering hardware but have to accept Snazzi's quality. Yes it is definitely well below VHS.

If you have more queries on Video CD production, please e-mail us. I do suggest a different encoder.

There are some on the market that costs about the same but produces better quality.

Hope to have helped.

-- Digital Human Multimedia (wired@tm.net.my), June 28, 1999.


I used the NTI CDMaker trial version to burn some test VCDs at various data rates as Gil described to check out the quality difference. Alas, my DVD player cannot handle data rates above 1.15 Mbps. Skips and freezes as it tries to play the VCD; probably is buffering and can't keep up with the data rate. Plays fine on PC and looks really good at about 2Mbps. I have a Pioneer DVL-909 combo DVD/LD/CD/VCD player. Anything else I can try to get this to work?

By way, the NTI CD Maker won't accept VCD .mpg files generated by DVC (Dazzle) stating that they are indeed not VCD 2.0 compliant. Strange, since Easy CD Creator accepts them just fine.

Thanks, Kevin

-- Kevin (delgadil@cisco.com), July 18, 1999.


Blockiness.

It's crazy to compress your files twice. Some capture cards such as the snazzi captures to mpeg1, but not whitebook standard. For clearest results, you should first capture in avi format and encode them to mpeg1 whitebook. If your card can't do this, then you should get a new one. If you could capture in mpeg1 whitebook format, then it will save you lots of time because encoding is time consuming.

-- (jellyrol@sfsu.edu), July 23, 1999.


That's strange. My mpeg files are accepted on NTI cd Maker 3.17. My vcds come out okay...incidently I can't use Adaptec Deluxe 3.5c. My file always gets rejected...

-- Don (rico_1@webtv.net), July 25, 1999.


No one can have it all: capture direct to MPEG-1 for speed with blocky, blurry videos as a result, or capture to any standard codec AVI first then encode to MPEG-1 later and wait for hours while encoding gets done but with much better looking videos at the end. Snazzi is good in what it does for speed; still, no-one should have any illusions as to the quality it produces: definitely nothing to write home about. Snazzi or otherwise, the one other thing pros do for quality is to filter the video before encoding. This can be h/w or s/w. After the AVI is captured, for example, the resulting video can be cleaned up using certain settings in DVMPEG, for one. This is necessary because VHS is really a noisy video medium and the encoder wastes its resources encoding this noise which consists largely of high frequencies at and above 5MHz. This is similar to what is done when encoding audio in making audio CDs: there is a low-pass filter at the digitizing input to prevent signals higher than 20KHz from upsetting the sampling at 44KHz (following the rule that the sampling frequency should at least be twice the highest intended frequency to be sampled). For h/w the only processor I'm aware of is Darimvision's M- filter card, which at $700 is pricey and uses an ISA bus in your PC. It accepts the output of your VCR, processes it, then passes it on to the capture card. If your source tape was okay, it will now look good on VCD; if it was unstable and noisy, it can now be at least be watchable on VCD. ...Hope I've helped. :)

-- Emmanuel Martinez (epmartinez@hotmail.com), August 28, 1999.

I own a Snazzi PCI capture card 2 months ago and have so far made 5 Video CD 2.0 using my Sony Digital Video Camera. The quality may not fantastic but still above average, especially playback on my Video CD player with my 29" TV. The quality is as good as the VHS copy which I have transfer to both my VCR and computer. I am very happy with this Snazzi so far because it really simple to use and not so fuzzy about harddisk space. I have no problem capturing more than 60 mins of video at one go. Never encounter any error/problem when capturing video with this Snazzi card. Now, I am in the process of capture 12X60 = 720 minutes of video into my computer. which going to be 12 Video CDs.

-- Mave Lee (mave_lee@hotmail.com), December 19, 1999.

Well said Emmanuel, I agree wholeheartedly. I believe in that adage... garbage in, garbage out. For better pictures though, I recommend that you shoot the video from the start with VCD or MPEG compression in mind.(if possible grab some old issues of videomaker magazine, it has some great articles on this subject). Here's what I do.

1. Light the subject up. Better light means less compensation by the camera and less noise is recorder.

2. Use a better quality camera for pin-point sharpness. (3ccd's are great)

3. Put the camera on a tripod or better still cut the amateurish zoom,pan and tilt mannerisms. A slow panning image makes for less blocky or pixelated backgrounds.

4. Capture using the Snazzi at the highest bitrate setting imaginable.

5. Beg, borrow or steal the goddamn fastest machine you can find. (dual processor NT with oodles of ram is excellent)

6. Use TMPEG encoder on that machine(yes TMPEG does accept MPEG streams as source files) with the noise reduction and sharpening options enabled. don't forget to use the VCD template (NTSC or PAL)

7. Press the start button and go get some sleep.

OR IF YOU HAVE LOTS OF CASH. GO GET A PROFESSIONAL CARD WHICH DOES IT ALL FOR YOU IN ONE GO.

ps. If anyone outthere has any comments on the Snazzi III, Provideo PV-251 or the VVmer cards do let me know. I'm thinking of getting one.

Regards,

-- ibarbosa (ibarbosa3@yahoo.com), February 01, 2002.


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