AVC CSC YCbCr HD Sample Code

This repository provides a sample implementation for converting YCbCr data to RGB using the CSC controller with the AVC hardware module hosted on the Media Engine.

Implementation Overview

Unlike VME-based approaches, the Media Engine's AVC hardware module handles color space conversion differently by processing:

• A Y plane (luminance)
• A packed CbCr plane (chrominance)

Data Format Requirements

The AVC hardware module requires YCbCr data to be organized in a specific band-based format:

• 16-pixel-wide vertical bands: Data must be chunked into these narrow vertical strips
• Alternating pattern: Within 32-pixel-wide blocks, bands alternate between left and right halves
  • First 16 pixels go to the left half
  • Next 16 pixels go to the right half
  • Pattern continues across the image width
• Hardware-specific layout: Preprocessing required using the included Python conversion script

Input Constraints

• Image dimensions:
  • For RGB565 output: width & height must be multiples of 32
  • For ARGB8888 output: width & height must be multiples of 64
• Band width requirement: width must be a multiple of 16

Generate YCbCr Planes

Example for a 960×960 image (maximum supported by the hardware in this configuration):

1. Generate NV12 data:

.\ffmpeg.exe -i csc960x960.png -vf "scale=960:960,format=nv12" -f rawvideo -pix_fmt nv12 nv12_full.bin -y

2. Convert for hardware use:

python ./n12ToHw.py nv12_full.bin 960 960 --max_chunk_height 480

Build & Run

make clean && make

Use arrow keys to move the canvas.

Special Thanks To

• The PSP homebrew community, for being an invaluable source of knowledge.
• All developers and contributors who have supported and continue to support the scene.

resources:

• psp wiki on PSDevWiki

m-c/d