Overall picture quality is intended to be comparable to VHS video.[3] Poorly compressed VCD video can sometimes be lower quality than VHS video, but VCD exhibits block artifacts rather than analog noise, and does not deteriorate further with each use.
352x240 (or SIF) resolution was chosen because it is half the vertical, and half the horizontal resolution of NTSC video. 352x288 is similarly one quarter PAL/SECAM resolution. This approximates the (overall) resolution of an analog VHS tape, which, although it has double the number of (vertical) scan lines, has a much lower horizontal resolution.
VCD video is mostly compatible with the DVD-Video standard, except for any video encoded at 23.976 frames per second, which must use 3:2 pulldown.
[edit] Audio
* Codec: MPEG-1 Audio Layer II
* Frequency: 44,100 hertz (44.1 kHz)
* Output: Dual channel or stereo
* Bitrate: 224 kilobits per second
o Rate Control: Constant bitrate
As with most CD-based formats, VCD audio is incompatible with the DVD-Video standard due to a difference in frequency; DVDs require 48 kHz, whereas VCDs use 44.1 kHz.
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