exfavbin の Ruby 版　FAVORITE のアレをアレするやつ

exfavbin.rb

require 'bin_utils'
require 'fileutils'
require 'oily_png'
require 'parallel'
require 'zlib'

class FavBin
    attr_reader :entries

    def initialize(bin)
        entry_count = BinUtils.get_int32_le(bin)
        filenames_offset = 8 + 12 * entry_count
        @entries = entry_count.times.map do |i|
            filename_offset = BinUtils.get_int32_le(bin, 8 + i * 12)
            offset = BinUtils.get_int32_le(bin, 12 + i * 12)
            length = BinUtils.get_int32_le(bin, 16 + i * 12)
            filename = bin.unpack1("@#{filenames_offset + filename_offset}Z*")
            data = bin.byteslice(offset, length)
            { name: filename.force_encoding('SJIS').encode('UTF-8'), data: data }
        end
    end

    def nvsg2png(data)
        data.force_encoding('ASCII-8BIT')
        hzc1 = data.slice(0, 12)
        raise 'invalid signature (expected hzc1)' unless hzc1[0, 4] == 'hzc1'
        original_length = BinUtils.get_int32_le(hzc1, 4)
        header_length = BinUtils.get_int32_le(hzc1, 8)
        header = data.slice(12, header_length)
        raise 'invalid signature (expected NVSG)' unless header[0, 4] == 'NVSG'
        # version = BinUtils.get_int16_le(header, 4)
        texture_type = BinUtils.get_int16_le(header, 6)
        width = BinUtils.get_int16_le(header, 8)
        height = BinUtils.get_int16_le(header, 10)
        # offset_x = BinUtils.get_int16_le(header, 12)
        # offset_y = BinUtils.get_int16_le(header, 14)
        entry_count = BinUtils.get_int32_le(header, 20)
        data = Zlib.inflate(data.slice((12 + header_length)..))
        raise 'data length not match' unless original_length == data.length
        if entry_count.zero?
            generate_png(data, width, height, texture_type)
        else
            size = data.length / entry_count
            entry_count.times.map do
                d = data.slice!(0, size)
                generate_png(d, width, height, type)
            end
        end
    end

    def generate_png(data, width, height, type)
        case type
        when 0
            ChunkyPNG::Image.from_bgr_stream(width, height, data)
        when 1, 2
            d = data.unpack('V*')
            d.map!{|e| (e >> 24) | (e << 8 & 0xffffff00)}
            ChunkyPNG::Image.from_abgr_stream(width, height, d.pack('V*'))
        when 3
            d = data.unpack('C*')
            d.map!{|e| (e << 24) | (e << 16) | (e << 8) | 0xff}
            ChunkyPNG::Image.from_abgr_stream(width, height, d.pack('V*'))
        when 4
            d = data.unpack('C*')
            d.map!{|e| e.zero? ? 0xff : 0xffffffff}
            ChunkyPNG::Image.from_abgr_stream(width, height, d.pack('V*'))
        end
    end
end

filename = ARGV[0]
dirname = File.basename(ARGV[0], '.*')
favbin = FavBin.new(File.binread(filename))

FileUtils.mkdir_p(dirname)
Parallel.each(favbin.entries) do |e|
    puts e[:name]
    if e[:data][0, 4] == 'hzc1' && e[:data][12, 4] == 'NVSG'
        pngs = favbin.nvsg2png(e[:data])
        if pngs.is_a?(Array)
            pngs.each_with_index do |png, i|
                png.save("#{dirname}/#{e[:name]}_#{i}.png")
            end
        else
            pngs.save("#{dirname}/#{e[:name]}.png")
        end
    else
        ext =
            case e[:data].unpack1('N')
            when 0x52494646 # RIFF
                'wav'
            when 0x4f676753 # OggS
                'ogg'
            when 0x89504E57 # PNG
                'png'
            when 0xffd8ffe0 # JPEG
                'jpg'
            end
        File.binwrite(ext ? "#{dirname}/#{e[:name]}.#{ext}" : "#{dirname}/#{e[:name]}", e[:data])
    end
end