def get_algorithm(filename, msglen, password):
if filename.endswith("jpeg") or filename.endswith("jpg"):
# PQ, F5, LSB
jpeg_data = libstegofile.jpeg_data_t()
jpeg_int = libstegofile.jpeg_internal_data_t()
err = libstegofile.io_jpeg_read(filename,jpeg_data, jpeg_int)
#TODO: ERROR (everywhere)
para = libstegofile.pq_parameter()
para.header_size = 0
para.quality = 0
if libstego.pq_check_capacity(jpeg_data, para) >= msglen:
libstegofile.jpeg_cleanup_data(jpeg_data)
libstegofile.io_jpeg_cleanup_internal(jpg_int)
return ["PQ",para]
para = libstegofile.f5_parameter()
if libstego.f5_check_capacity(jpeg_data, para) >= msglen:
libstegofile.jpeg_cleanup_data(jpeg_data)
libstegofile.io_jpeg_cleanup_internal(jpg_int)
return ["F5",para]
para = libstegofile.lsb_parameter()
# if libstego.lsb_check_capacity(jpeg_data, para) >= msglen:
# libstegofile.jpeg_cleanup_data(jpeg_data)
# libstegofile.io_jpeg_cleanup_internal(jpg_int)
# return ["LSB",para]
libstegofile.jpeg_cleanup_data(jpeg_data)
libstegofile.io_jpeg_cleanup_internal(jpg_int)
return
elif filename.endswith("gif"):
# AdvGifshuffle, Gifshuffle, Frirui, Sort/Unsort, LSB
palette_data = libstegofile.palette_data_t()
gif_int = libstegofile.gif_internal_data_t()
err = libstegofile.io_gif_read(filename, palette_data, gif_int)
para = libstegofile.gifshuffle_parameter()
if libstego.gifshuffle_check_capacity(palette_data, para) >= msglen:
return ["Adv. Gifshuffle", para]
# no elif gifshuffle since it has the same capacity that adv gusfhuffle has
para = libstegofile.frirui_parameter()
para.method = 0;
para.size = 100;
para.password = password
para.pwlen = len(password)
#para.method = 1;
#para.threshold = 574;
#para.password = password
#para.pwlen = len(password)
#para.method = 1;
#para.threshold = 1148;
#para.password = password
#para.pwlen = len(password)
#para.method = 2;
#para.password = password
#para.pwlen = len(password)
#para.method = 1;
#para.threshold = 2295;
#para.password = password
#para.pwlen = len(password)
#para.method = 0;
#para.size = 6;
#para.password = password
#para.pwlen = len(password)
# DONE: multiple parameter sets for frirui from Matthias here!
if libstego.frirui_check_capacity(palette_data, para) >= msglen:
return ["Frirui", para]
para = libstegofile.sortunsort_parameter()
if libstego.sortunsort_check_capacity(palette_data, para) >= msglen:
return ["Sort/Unsort", para]
"""para = libstegofile_lsb_parameter_t()
#TODO: LSB Wrappers for structs like palette_data -> Jan ?
if libstego.lsb_check_capacity(palette_data, para) >= msglen:
return ["LSB", para]"""
elif filename.endswith("png"):
# CPT, Battlesteg, LSB
rgb_data = libstegofile.rgb_data_t()
png_int = libstegofile.png_internal_data_t()
err = libstegofile.io_png_read(filename, rgb_data, png_int)
for i in [2,4,6,8]:
para = libstegofile.cpt_parameter()
para.block_width = i;
para.block_height = i;
para.password = password
para.pwlen = len(password)
if libstegofile.cpt_check_capacity(rgb_data, para) >= msglen:
return ["CPT", para]
para = libstegofile.battlesteg_parameter()
para.startbit = 7
para.move_away = 3
para.range = 5
para.password = password
para.pwlen = len(password)
# parameter set "capacity"
#para = libstegofile.battlesteg_parameter()
#para.startbit = 6
#para.move_away = 3
#para.range = 5
#para.password = "******"
#para.pwlen = 8
if libstegofile.battlesteg_check_capacity(rgb_data, para) >= msglen:
return ["BattleSteg", para]
"""para = libstegofile.lsb_parameter()
para.password = password
para.pwlen = len(password)
para.select_mode = 2
if libstegofile.lsb_check_capacity(rgb_data, para) >= msglen:
return ["LSB", para]"""
elif filename.endswith("wav"):
# Phase Coding, Echo Hiding, LSB
pass
elif filename.endswith("svg"):
# SVGSteg
svg_data = libstegofile.svg_data_t()
svg_int = libstegofile.svg_internal_data_t()
err = libstegofile.io_svg_read(filename, svg_data, svg_int)
if err != 0:
return None
para = libstegofile.svg_parameter_t()
para.password = password
para.pwlen = len(password)
para.first_embed_digit = 3
fits = False
if libstego.svg_check_capacity(svg_dat, para) >= msglen:
fits = True
libstegofile.svg_cleanup_data(svg_dat)
libstegofile.svg_cleanup_internal(svg_int)
if fits == True:
return ["SVG", para]
def get_best_method(filename, filetype, msglen, password):
# setup all methods
setup_methods(password)
# get methods for current file type
num_selected, sel_method = get_methods_for_filetype(filetype)
for i in [0, num_selected-1]:
fits = False
if method_to_algo[i] == "PQ":
# prepare data strucures
jpeg_data = libstegofile.jpeg_data_t()
jpeg_int = libstegofile.jpeg_internal_data_t()
# read file data
err = libstegofile.io_jpeg_read(filename, jpeg_data, jpeg_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstego.pq_check_capacity(jpeg_data, para) >= msglen:
fits = True
# cleanup
libstegofile.jpeg_cleanup_data(jpeg_data)
libstegofile.io_jpeg_cleanup_internal(jpg_int)
if method_to_algo[i] == "F5":
# prepare data strucures
jpeg_data = libstegofile.jpeg_data_t()
jpeg_int = libstegofile.jpeg_internal_data_t()
# read file data
err = libstegofile.io_jpeg_read(filename, jpeg_data, jpeg_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstego.f5_check_capacity(jpeg_data, para) >= msglen:
fits = True
# cleanup
libstegofile.jpeg_cleanup_data(jpeg_data)
libstegofile.io_jpeg_cleanup_internal(jpg_int)
if method_to_algo[i] in ["Adv. Gifshuffle", "Gifshuffle"]:
# prepare data strucures
palette_data = libstegofile.palette_data_t()
gif_int = libstegofile.gif_internal_data_t()
# read file data
err = libstegofile.io_gif_read(filename, palette_data, gif_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstego.gifshuffle_check_capacity(palette_data, para) >= msglen:
fits = True
# cleanup
libstegofile.io_gif_cleanup_data(palette_data)
libstegofile.io_gif_cleanup_internal(gif_int)
if method_to_algo[i] == "Frirui":
# prepare data strucures
palette_data = libstegofile.palette_data_t()
gif_int = libstegofile.gif_internal_data_t()
# read file data
err = libstegofile.io_gif_read(filename, palette_data, gif_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstego.frirui_check_capacity(palette_data, para) >= msglen:
fits = True
# cleanup
libstegofile.io_gif_cleanup_data(palette_data)
libstegofile.io_gif_cleanup_internal(gif_int)
if method_to_algo[i] == "Sort/Unsort":
# prepare data strucures
palette_data = libstegofile.palette_data_t()
gif_int = libstegofile.gif_internal_data_t()
# read file data
err = libstegofile.io_gif_read(filename, palette_data, gif_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstego.sortunsort_check_capacity(palette_data, para) >= msglen:
fits = True
# cleanup
libstegofile.io_gif_cleanup_data(palette_data)
libstegofile.io_gif_cleanup_internal(gif_int)
if method_to_algo[i] == "CPT":
# prepare data strucures
rgb_data = libstegofile.rgb_data_t()
png_int = libstegofile.png_internal_data_t()
# read file data
err = libstegofile.io_png_read(filename, rgb_data, png_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstegofile.cpt_check_capacity(rgb_data, para) >= msglen:
fits = True
# cleanup
libstegofile.io_png_cleanup_data(rgb_data)
libstegofile.io_png_cleanup_internal(png_int)
if method_to_algo[i] == "Battlesteg":
# prepare data strucures
rgb_data = libstegofile.rgb_data_t()
png_int = libstegofile.png_internal_data_t()
# read file data
err = libstegofile.io_png_read(filename, rgb_data, png_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstegofile.battlesteg_check_capacity(rgb_data, para) >= msglen:
fits = True
# cleanup
libstegofile.io_png_cleanup_data(rgb_data)
libstegofile.io_png_cleanup_internal(png_int)
if method_to_algo[i] == "SVG Steg":
# prepare data strucures
svg_data = libstegofile.svg_data_t()
svg_int = libstegofile.svg_internal_data_t()
# read file data
err = libstegofile.io_svg_read(filename, svg_data, svg_int)
if err != 0:
# TODO better error handling -> detailed message what went wrong
# by using the 'lstg_errno' code
return None
# check if message fits with the current params
para = methods[i]
if libstego.svg_check_capacity(svg_data, para) >= msglen:
fits = True
# cleanup
libstegofile.svg_cleanup_data(svg_data)
libstegofile.svg_cleanup_internal(svg_int)
if method_to_algo[i] == "Echo Hiding":
# TODO implement
pass
if method_to_algo[i] == "Phase Coding":
# TODO implement
pass
if method_to_algo[i] == "LSB":
# TODO implement
pass
if fits:
return i
return None