VPBE VPFE YUV IPIPE

the existing video processing back end(VPBE)

The VPFE port provides an interface for CCD/CMOS imager modules and video decoders. The VPBE

Image Data Output - Video Processing Back End (VPBE)

The Video Encoder/Digital LCD interface module in the video processing back end has an external signal

interface for digital image data output as described in Table 2-7 and Table 2-8.

The digital image data output signals support multiple functions / interfaces, depending on the display

mode selected. The following table describes these modes. Parallel RGB mode with more than RGB565

signals requires enabling pin multiplexing to support (i.e., for RGB666 mode).

The Video Processing Back End (VPBE) is a sub-module of the Video Processing Subsystem (VPSS).

The Video Processing Back End (VPBE) is a sub-module of the Video Processing Subsystem (VPSS).

The VPBE is designed to interface with a variety of LCDs and an internal DAC module. There are two

asynchronous clock domains in the VPBE: an internal clock domain and an external clock domain. The

internal clock domain is driven by the VPSS clock (PLL1 SYSCLK4). The external clock domain is

configurable; you can select one of five source:

• 24 MHz crystal input at MXI1

• 27 MHz crystal input at MXI2 (optional feature, not typically used)

• PLL1 SYSCLK3

• EXTCLK pin (external VPBE clock input pin)

• PCLK pin (VPFE pixel clock input pin)

• Video Processing Back End (VPBE)

– On Screen Display (OSD)

– Video Encoder Engine (VENC)

 and video processing front end (VPFE)

provides hardware On Screen Display (OSD) support and composite NTSC/PAL and digital LCD output.

• Video Processing Front End (VPFE)

– CCD Controller (CCDC)

– Image Pipe (IPIPE)

– H3A Engine (Hardware engine for computing Auto-focus, Auto white balance, and Auto exposure)

The VPFE port provides an interface for CCD/CMOS imager modules and video decoders.

YUV is a color space typically used as part of a color image pipeline. It encodes a color image or video taking human perception into account, allowing reduced bandwidth for chrominance components, thereby typically enabling transmission errors or compression artifacts to be more efficiently masked by the human perception than using a "direct" RGB-representation.

출처 : http://www.ti.com/lit/ds/symlink/tms320dm355.pdf

          http://en.wikipedia.org/wiki/YUV

The Image Pipe (IPIPE) is a programmable hardware image processing module on DM35x that generates image data in YCbCr-4:2:2 format from RAW CCD/CMOS data. The IPIPE can also be configured to operate in a resize only mode, which allows YCbCr-4:2:2 to be resized without applying the processing of every other module in the IPIPE.

The IPIPE supports resizing from x1/16 scale-down to x8 scale-up in both the horizontal and vertical directions, with the output width no more than 1344 in pixel. But applications may implement an algorithm to call IPIPE multiple times to resize an image wider than 1344 pixels.

The Linux IPIPE device driver provides a device node /dev/dm355_ipipe, which allow applications to use IPIPE module.

The IPIPE resizer demo shows how to configure IPIPE to scale a YUV image, which reads a YUV file, and writes the scaled output into a file.

출처 : http://processors.wiki.ti.com/index.php/IPIPE_resizer_demo