Ancillary Data Capture

3.6 Ancillary Data Capture

The BT.656 and some Y/C specifications includes provision for carrying ancillary (nonvideo) data within the horizontal and vertical blanking regions. Horizontal ancillary (HANC) data appears between the EAV code and SAV codes. Vertical ancillary (VANC) data, also called vertical blanking interval (VBI) data, appears during the active horizontal line portion of vertically blanking (for example, after an SAV with V = 1).

3.6.1Horizontal Ancillary (HANC) Data Capture

No special provisions are made for the capture of HANC data. HANC data may be captured using the normal video capture mechanism by programming VCXSTRT to occur before the SAV (when HCOUNT is reset by the EAV code) or by programming VCXSTOP to occur past the EAV code (when HCOUNT is reset by the SAV code). Note that the EAV code and any subsequent HANC data will still be YCbCr separated. Software must parse the Y, Cb, and Cr memory buffers to determine any HANC data presence and to reconstruct the HANC data. The VCTHRLD value and DMA size must be programmed to comprehend the additional samples. You must disable scaling and chroma re- sampling when including the capture of HANC data to prevent data corruption.

3.6.2Vertical Ancillary (VANC) Data Capture

VANC (or VBI) data is commonly used for such features as teletext and closed- captioning. No special provisions are made for the capture of VBI data. VBI data may be captured using the normal capture mechanism by programming VCYSTART to occur before the first line of active video on the first line of desired VBI data. (VCOUNT must be reset by an EAV with V = 1). Note that the VBI data will be YCbCr separated. Software must parse the Y, Cb, and Cr memory buffers to determine any VBI data presence and to reconstruct the VBI data. You must disable scaling and chroma resampling when the capture of VBI data is desired or the data will be corrupted by the filters.

SPRU629

Video Capture Port

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Texas Instruments TMS320C64x DSP manual Ancillary Data Capture, Horizontal Ancillary Hanc Data Capture
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TMS320C64x DSP specifications

The TMS320C64x DSP family from Texas Instruments represents a significant milestone in the realm of digital signal processing. Launched as part of the C6000 series, the C64x DSPs are designed for high-performance applications requiring intensive computational capabilities, such as telecommunications, audio processing, video processing, and industrial control systems.

One of the standout features of the TMS320C64x DSP is its VLIW (Very Long Instruction Word) architecture, which allows for an exceptionally high level of parallelism. This architecture enables multiple instructions to be executed simultaneously, boosting the overall throughput and allowing for complex data processing tasks to be completed more quickly than with conventional DSPs.

The C64x DSPs also boast an impressive clock frequency range, typically up to 1 GHz, delivering substantial computational power for real-time processing goals. Additionally, these processors feature extensive on-chip memory, including L1 and L2 cache, which significantly enhances data access speeds and helps reduce bottlenecks during high-demand processing tasks.

Another key characteristic of the TMS320C64x family is its support for advanced instruction sets optimized for specific applications. These include SIMD (Single Instruction, Multiple Data) capabilities, allowing for efficient handling of large datasets often involved in multimedia processing or complex signal manipulation.

For connectivity, these DSPs often integrate advanced interfaces such as EMIF (External Memory Interface) and McBSP (Multichannel Buffered Serial Port), facilitating seamless interaction with a variety of peripheral devices. This ensures that the DSP can suit different application needs and integrate well into various system architectures.

Texas Instruments emphasizes low power consumption with the C64x DSPs, making them ideal for portable or energy-sensitive applications. Advanced power management techniques and technologies, such as dynamic voltage and frequency scaling, are incorporated to further enhance energy efficiency without compromising performance.

In summary, the Texas Instruments TMS320C64x DSP family stands out due to its high-performance capabilities driven by a VLIW architecture, high clock speeds, extensive memory options, a rich instruction set, and advanced connectivity features, all while maintaining power efficiency. These characteristics make it an exceptional choice for developers looking to integrate robust digital signal processing into their applications, whether in telecommunications, audio and video processing, or embedded control systems.
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