svcd -> vcd?

[madeyalook]

hi, i juss got a normal sized movie svcd, which is 3 mpegs files long..each just a little over 700mb.. if i use tmpgenc and convert it back to ntsc film, will it the file be about 1.7 gb? and will i lose a lotta quality? thnx.

[Vejita-sama]

You seem to be asking two questions, so first a little back ground.

MPEG file size is determined by two factors: bitrate and soure runtime. These are the ONLY factors that affect the file size. Resolution, frames per second, source file size, etc. have no affect on the size on the encoded MPEG file. They do however affect quaility.

As a general rule the higher the bitrate and resolution the better the quaility of your encoded MPEG file (if your source is good). With that in mind the standards are:

VCD - MPEG1 352x240 @ 1150kbit/s (audio mpeg1 layer 2 @ 224kbit/s)

SVCD - MPEG2 480x480 @ 2520kbit/s (audio mpeg1 layer 2 @ 224kbit/s)

So what makes SVCD better than VCD, is the higher bitrate and resolution. If I made a xVCD: MPEG1 480x480 @ 2520kbit/s it would look the same as a SVCD.

So to answer your question. If you convert a SVCD to VCD, you'll lower the bitrate and those the file size (for VCD 1min=10MB of data). The quaility will also decrease because it's a lower resolution/bitrate.

However, changing the frame rate (film vs. NTSC) will have NO effect on file size. Hope that helps...

[madeyalook]

thnx.. but will it be a dramatic decrease in quality or just a little ?

[puertorican138]

thnx.. but will it be a dramatic decrease in quality or just a little ?

It could be dramatic or a little loss depending on what bitrate you use and such.