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Texas Instruments TMS320C64x DSP manual Edge Pixel Replication, Sav, Eav

Models: TMS320C64x DSP

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Video Input Filtering

3.5.4Edge Pixel Replication

Because the filters make use of preceding and trailing samples, filtering arti- facts can occur at the beginning of the BT.656 or Y/C active line because no samples exist before the SAV code, and at the end of the BT.656 active line because no samples exist after the EAV code. In order to minimize artifacts, the first m samples after sample 0 (where m is the maximum number of preceding samples used by any of the filters) are mirrored to the left of sample 0 and the last m samples before the last sample are mirrored to the right of the last sample.

Figure 3–15 shows edge pixel replication assuming an m value of 3. Sample a is the first sample after the SAV code. Therefore, samples b–d are mirrored to the left of sample a to provide values for the filter calculations on the first few pixels in the line. Likewise, samples n – 1 to n – 3 are mirrored to the right of the last sample n to provide values for the last few pixels on the line.

Note that edge pixel replication only comes into effect when the full BT.656 stream is being captured. If VCXSTART is greater than 0, then only some of the leading edge replicated pixels are used by the filter. If VCXSTART is greater than m, then none of the leading edge replicated pixels are used. Similarly, if VCXSTOP is less than the number of samples before EAV, then none or only some of the trailing edge replicated pixels are used by the filters.

Figure 3–15. Edge Pixel Replication

d

SAV

 

a

b

c

d

e

n – 4 n – 3 n – 2 n – 1

n

EAV

 

 

 

 

 

 

 

Active line

 

 

c

b

a

b

c

d

e

n – 4 n – 3 n – 2 n – 1

n

n – 1 n – 2 n – 3

Leading edge replicated pixels

 

 

Trailing edge replicated pixels

 

 

 

–

Luma (Y)

–

Chroma (Cb/Cr)

 

sample

 

samples

SPRU629

Video Capture Port

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Texas Instruments TMS320C64x DSP manual Edge Pixel Replication, Sav, Eav
Page 90 Page 92

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.