The TW2837 features four high-quality NTSC/PAL video decoders, two-color display controllers, and dual video encoders, and includes four built-in analog anti-aliasing filters, four 10-bit ADC converters, proprietary digital gain/clamp controllers, high-quality Y/C separators to reduce cross noise and a high-performance free zoom. Built-in four motion, blind and night detectors for added safety system features.
The TW2837 features a flexible video display/recording/playback controller, including basic display and MUX capabilities. At the same time, it also has excellent graphics overlay function, which can display OSD bitmap, single frame, two-dimensional array frame, mouse pointer, etc. A built-in channel ID codec allows automatic decoding and display on playback, and an attached zoom on playback supports multi-frame functionality for the same field or frame image.
The TW2837 contains two video encoders and three 10-bit digital-to-analog converters to provide two composite or s videos, and also includes audio codecs with four audio ADC and one ADC. The built-in audio controller can generate digital output for recording/mixing and accept digital input for playback. It can also be extended to 8/16 channel video controllers, using chip-to-chip cascading connections.
Functional Description 【Video Input】
TW2837 has five input interfaces, consisting of one digital video input and four analog composite video inputs. The four analog video inputs are converted to a digital video stream by a 10-bit ADC and brightness/chrominance processor in four built-in video decoders. The digital input for playback applications is decoded by the ITU-R internal BT656 decoder and fed into the video control section and channel ID decoder. Each built-in video decoder has its own motion detector and dual zoom. Four additional zoomers are also embedded with the playback display application. The structure of the video input is shown below.
Block Diagram
Features
● Accepts all NTSC (M/N / 4.43) /PAL(B/D/G/H/I/K/L/M/N/60) standards with auto detection
● Integrated four video analog anti - aliasing filters and 10-bit CMOS ADCs
● High performance the adaptive 4 h comb filters for all NTSC/PAL standards
● IF compensation filter for improvement of color demodulation
● Color Transient Improvement (CTI)
● Automatic white peak control
● Programmable hue, saturation, contrast, brightness and sharpness
● Proprietary fast video locking system for non - realtime application
● High performance horizontal and vertical scaler for each path including playback input
● Four built - in motion detectors with 16 x12 cells and blind and night detectors
● Additional digital input for playback with ITU - R BT.656 standard
● Auto cropping/strobe for playback input with Channel ID decoder
● Supports four channel full D1 record mode
