UIUC ECE 385 - A .GIF decoder built for a DE2-115 development FPGA board

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Animated video

Resources:

https://www.matthewflickinger.com/lab/whatsinagif/bits_and_bytes.asp

https://commandlinefanatic.com/cgi-bin/showarticle.cgi?article=art011

• Source for LZW.h

https://en.wikipedia.org/wiki/GIF#File_format

Setup:

cd gifplayer_1.0/software/test
main.c -> set ON_NIOS = 0; if developing locally

clang main.c -Wall -g -o test && ./test

Stipulations:

• Gifs with even X Y dimensions seem are the only ones that fully display properly, there is a glitch accessing upper/lower bytes when using odd sizes
• The GIF size is severly limited based off of SRAM space and overflows of the address space when reading subsequent frames
• ~10Kb gif size with ~1.2 Megabytes for decoded frames
• Some AEBs result in a failed assert and must be removed from the file
• There is a custom SRAM controller inside the synthesis folder, which must be restored if platform designer regenerates HDL

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