1: Introduction
MPEG4000-D4 Hardware Reference Manual
© 2011 Advanced Micro Peripherals
Document version A.01
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Functional summary
Signal sources
The MPEG4000-D4 is designed to capture and record from up to four separate
and unrelated video sources simultaneously. Each of the four video input channels
of the MPEG4000-D4 features a video frame grabber and an audio digitizer. Each
frame grabber contains a digital NTSC/PAL video and each video channel has an
associated audio input. A single audio input is associated with each live video
channel.
Video digitization
Composite NTSC or PAL video is input to the MPEG4000-D4 through the header
VID1. The video is AC-coupled and fed to the on-board decoders of the individual
frame grabbers. The video decoders automatically detect whether the incoming
video signal is NTSC or PAL and generate the correct timing output signals. Each
video channel is first decoded to chrominance and luminance signals and then
digitized by high speed analog-to-digital (A2D) converters. The A2Ds output are
passed to the MPEG-4 encoder.
