libugomemo

C library for parsing and encoding Nintendo Flipnote Studio animation formats.

Supported formats

Format	Extension	Platform	Parse	Decode video	Decode audio	Encode video	Encode audio
PPM	.ppm	DSi	Yes	Yes	Yes	Yes	Yes
KWZ	.kwz	3DS	Yes	Yes	Yes	Yes	Yes
UGO	.ugo	DSi	Yes	-	-	-	-
NBF	.nbf	DSi	Yes	Yes	-	-	-
NPF	.npf	DSi	Yes	Yes	-	-	-
LST/PLS	.lst/.pls	DSi/3DS	Yes	-	-	-	-
KWZPCF	.kwzpcf	3DS	Yes	-	-	-	-

Building

make release   # static library  -> build/release/libugomemo.a
make shared    # shared library  -> build/shared/libugomemo.dylib (or .so)
make debug     # debug static    -> build/debug/libugomemo.a

Dependencies

• OpenSSL (libcrypto): SHA-256, SHA-1 hashing and DER key loading
• GNU Multiple Precision (libgmp): RSA operations
• zlib: gzip decompression and CRC32 hashing

Usage

#include <ugomemo.h>

// Open and parse a KWZ file
kwz_ctx *kwz = kwz_open("animation.kwz");
if (!kwz) return 1;

printf("Frames: %u\n", kwz_get_frame_count(kwz));
printf("Author: %s\n", kwz_get_current_username(kwz));

// Decode a frame to RGB pixels (caller must free)
rgb24_pixel *pixels = kwz_decode_frame_alloc(kwz, 0);
// pixels is 320*240 rgb24_pixel values
free(pixels);

// Decode an audio track (caller must free)
u32 sample_count;
i16 *audio = kwz_decode_track_alloc(kwz, 0, -1, &sample_count);
free(audio);

kwz_cleanup(kwz);

PPM files work the same way:

ppm_ctx *ppm = ppm_open("animation.ppm");
printf("Frames: %u\n", ppm_get_frame_count(ppm));

rgb24_pixel *pixels = ppm_decode_frame_alloc(ppm, 0);
free(pixels);

ppm_close(ppm);

Python integration

Build the shared library and load it with ctypes:

import ctypes
lib = ctypes.CDLL("path/to/libugomemo.dylib")

The convenience API (kwz_open, kwz_get_*, kwz_decode_frame_alloc, etc.) is designed for FFI use -- all functions take and return simple types or opaque pointers.