NO blockiness in .MPG, but HIGH blockiness in .DAT

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This is what has been happening lately: After the MPEG encoding, I check out the MPEG file/s and are Ok. Then I burn the VCD and I have a lot of blockiness when I watch it in my 36X cd-rom and in other high speed CD-ROM. But... if I watch the VCD in my CD-Recorder or in a low speed CD-ROM like 24x there is no blockiness at all. Furthermore, if I copy the .dat files from the VCD into my hard drive, they play Ok again. Is somebody experiencing this problem? Maybe it's time for me to buy a new burning unit, but before spending money I would like to have some comments IF you've been experiencing something like this. Thank you all.

-- Matias (mpetrel@fi.uba.ar), March 04, 2000

Answers

I'm so tired of blockiness in VCD's that I'm about ready to give up on them. The only solution I've found so far is to use a higher bit rate. I don't see a difference between my mpg's and dat's though. Are you watching them both under the exact same conditions?

-- Al McCraw (amccraw@ix.netcom.com), March 04, 2000.

Blockiness on the resulting VCD which were not apparent on the MPEG clips used to make it may be the result of inferior blank CDs and/or using a high recording speed. I was exactly in the same situation; I use a Teac CD-RS55 CD-R SCSI drive. Some VCDs I created using 4x (maximum on this Teac) showed a lot of blockiness on playback on a DVD-settop, but had none when I recorded at 2x. Interestingly there seemed to be more blockiness when recorded at 1x compared with 2x. Unbranded 75cent CD-R media also produced far more blockiness even at 2x than Kodak CD-R ultima.

-- EMartinez (epmartinez@yahoo.com), March 05, 2000.

Sorry about my last reply....this VCD business is frustrating. It is true that using better media will help but even trying that and using the different write speeds I still get blockiness around moving objects to the point I am still trying to improve the quality. Most blank CD's are actually made for recording audio or data and just aren't the quality you need for Video. I've heard of and tried a brand called Mitsui that is suopposedly one of the best you can buy but still have blockiness and the original source was a commercially made VHS tape. The only solution I've found so far is to encode at a higher bit rate but then if you're using EZ CD Creator it won't accept your mpg file as a valid file and you have to use a different software such as Nero or NTI both have free demo versions and neither has a mneu feature.

-- Al McCraw (amccraw@ix.netcom.com), March 06, 2000.

Matias

I noticed from experience that 2x is the best burning speed for vcd. 4x tends to underburn and cause skippy and blocky picture and 1x leads to overburning that renders the vcd unreadable sometimes. Stick to 2x and you are quite safe.

The problem of underburning is aggravated when you play on a fast CDROM. By deduction, the effect of overburning (1x speed) can be lessened with a fast CDROM (Haven't really verified this yet).

-- Daniel Lee (siangneng@hotmail.com), March 06, 2000.


Thanks Daniel....I've been using 2x

-- Al McCraw (amccraw@ix.netcom.com), March 07, 2000.


Thank you all guys for your input.

Al, I'm not talking about the kind of blockiness that you mention, that's a whole different subject. My problem is, as Daniel and Emartinez noted, the blockiness generated in the .DAT that was not in the original .MPG.

Regarding the burning speed, yes, I also found that 2x is better than 1x (kind of mystery but is what my experiments told so I'm stick with 2x). The media used is Mitsui silver. Some people say it's the best. I don't really think there is one sole best brand of media, but surely people won't be calling "the best" a brand that isn't average at least. There is also the strange matter that the VCDs play fine in the CD-Recording unit which burn them or in low speed CDroms. I'm beginning to think that perhaps today's CD-ROMS are of lower quality than previous. I even had lots of problems playing plain AudioCDs in high-speed CDroms, so maybe a highspeed CDrom is better for data but worst for Audio/Video CDs, since the arrangement of data in Audio and VideoCDs is pretty similar. Any further idea will be appreciated. Thanx again!

-- Matias (mpetrel@fi.uba.ar), March 09, 2000.


Hello Matias. You problems is simple. If you can copy your VCD into hard disk, dont blame your CD Recorder. It's CD-ROM. Disk VCD has block sise 2352, like CD-DA and has no ECC correction. 36X CD-Rom drive can't read AudioCD as well, like 24X speed or lower... It's depends his construction.I make industrial Mastering VCD and have this problem every day. Try to use CD-R media for CD-Audio. Don't matter if it's was Silver or Golg. The Best results I had with disks who has very light green transparency layer named "cyanine type 5" or "cyanine type 7". I work with this disks last 3 year. For example: Kodak Gold, Traxdata Gold, BASF Gold or Silver (in clip Tray) Ritek e.t.c.

-- Pavel (dvcd@mai.ru), March 10, 2000.

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