Why does speed of encoding MPG vary here?

[Twiddlebug]

Hello All. This is my first post. My question pertains to MPEG and its conversion to DivX.

Many times when I download mpg files of some of my favourite TV shows (Cartoons), the files are approx 220 MB, 352x240 and when I encode it to DivX, it will encode at a speed between 40-50 fps.

When I create my own MPG files from TV shows with my ATI All in Wonder Radeon 7500, to achieve a decent picture, I use a bitrate of about 8 MBits per second, 640x480.

My first question is how do these other people get such a good looking MPG made with such a small file size? There's is 220 MB usually while mine goes to about 1 GB. I know that my sound is not compressed yet but that still does not account for the huge size. If I lower the Bitrate, the pic quality deteriorates dramatically. Same with the resolution.

Of course after I encode to DivX that's not a problem , but my second question is why does my encoding process of the MPGs that I make go slow at about 16FPS while the MPGs I download will convert at 40FPS?

I am stumped. Any help would be GREATLY appreciated.

Thanks.

[techno]

Firstly, never use ATI card to capture! Use hauppauge WinTV GO PCI with these settings:

NO RECOMPRESSIOON
YU12
320*240
25/30fps
CD quality audio

this saves it as AVI then you use TMPGENC to encode to MPEG, at least 2 times, you will notice better quality and low file size



Techno

[Twiddlebug]

Do you mean buy an entire new card? I just bought ths one and just found out that RealMagic is releasing a new capture card (sans TV Tuner) .. damn.

If I do not compress it, what find of file size am I looking at? I trie that once and it was so much data, that the hard drive can simply not write that fast, plus the filesize would be Gig upon gig...

Your thoughts??

[techno]

The card I said is REALLY REALLY cheap ($45)

It will be big file sizes, 5 mins = 650MB because it is not compressing but giving u QUALITY, not quantity!

The card does not take ANY system resources (maybe 5%) and needs a minimum of a P75 to run on.

You will only lose 15% of frames in total and is REALLY GOOD STUFF!!!

Techno

[Twiddlebug]

Thanks for the advice.

I am a BIG fan of the Hollyeood Magic DVD decoder Card and now the are releasing a sweet looking capture card ..MPG1 and MPG2 all processed by the card, not the CPU. Check it out.

https://www.sigmadesigns.com

Thanks again.

[techno]

It's good but...

it is not good to capture and compress at the same time as you will lose quality and it then becomes waste of time.

But yeh, it is good, I trust my trusty Hauppauge WinTV GO PCI card.

I told a guy to buy it recently, he bought it and was impressed with the quality, not from the TV but from the VCR!! Althought VCR is not good quality.

Give it a try!

Techno