/* ***************************************************************************** * libg1m/picture.h -- libg1m picture formats. * Copyright (C) 2017 Thomas "Cakeisalie5" Touhey * * This file is part of libg1m. * libg1m is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 3.0 of the License, * or (at your option) any later version. * * libg1m is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with libg1m; if not, see . * ************************************************************************** */ #ifndef LIBG1M_PICTURE_H # define LIBG1M_PICTURE_H # include /* This file describes the picture formats CASIO has used for various purposes * (screenshots, pictures, screenstreaming), and that libg1m is able to * decode. * * The formats pictures should fit in a `g1m_pictureformat_t`. * They are more or less organized as 0xBBVS, where BB is the number of bits * each pixel occupy (in total), V is the variation for this number of bits, * and S is the special hex digit (e.g. reverse). */ typedef unsigned int g1m_pictureformat_t; /* ************************************************************************** */ /* Monochrome pictures with fill bits */ /* ************************************************************************** */ /* In this format, each bit represents a pixel (so one byte contains eight * pixels). If the width is not divisible by eight, then the last bits of the * last byte of the line are unused (fill bits), and the next line starts at * the beginning of the next byte ; this makes the navigation between lines * easier, but takes up more space. * * An off bit (0b0) represents a white pixel, and an on bit (0b1) represents * a black pixel. Reverse white and black in the `_r` special type. */ # define g1m_pictureformat_1bit 0x0100 # define g1m_pictureformat_1bit_r 0x0101 /* To calculate the size, it's simple: just calculate the number of bytes * a line occupies, then multiply it by the number of lines. */ # define g1m_picturesize_1bit(W, H) \ ((((W) / 8) + !!((W) % 8)) * (H)) # define g1m_picturesize_1bit_r(W, H) \ g1m_picturesize_1bit((W), (H)) /* ************************************************************************** */ /* Packed monochrome pictures */ /* ************************************************************************** */ /* Packed monochrome pictures is basically the same than the previous format, * except there are no fill bits: if a picture width is 6 pixels, then the * second line will start at the seventh bit of the first byte (where it would * start at the first bit of the second byte with fill bits). * * The navigation to a line is less easy as it takes at least one division. */ # define g1m_pictureformat_1bit_packed 0x0110 # define g1m_pictureformat_1bit_packed_r 0x0111 /* To calculate the size, find out the number of occupied bits, divide by * eight to get the bytes, and make sure to keep an extra byte if there are * left bits. */ # define g1m_picturesize_1bit_packed(W, H) \ (((W) * (H) / 8) + !!((W) * (H) % 8)) /* ************************************************************************** */ /* Old monochrome format */ /* ************************************************************************** */ /* The old monochrome format used by CASIO is basically a normal monochrome * format (the width is usually 96 or 128, so no need for fill bits), except * that it starts with the last byte (where the bits are in left to right * order), but then it goes from right to left, and from bottom to top. */ # define g1m_pictureformat_1bit_old 0x0120 /* The size is the same as for normal 1-bit monochrome pictures, only the * byte order changes. */ # define g1m_picturesize_1bit_old(W, H) \ g1m_picturesize_1bit(W, H) /* ************************************************************************** */ /* Dual monochrome format */ /* ************************************************************************** */ /* This is the format used for the Prizm's projector mode. It is composed of * two monochrome pictures (with sizes divisible by eight). * It is basically gray pictures, with white, light gray, dark gray and * black. */ # define g1m_pictureformat_2bit_dual 0x0200 /* To calculate the size, well, we just have two monochrome screens. */ # define g1m_picturesize_2bit_dual(W, H) \ (g1m_picturesize_1bit(W, H) * 2) /* ************************************************************************** */ /* 4-bit RGB_ format */ /* ************************************************************************** */ /* This is a 4 bit per pixel format. There is no need for fill bits (?). * Each nibble (group of 4 bits) is made of the following: * - one bit for red (OR by 0xFF0000); * - one bit for green (OR by 0x00FF00); * - one bit for blue (OR by 0x0000FF); * - one alignment bit. */ # define g1m_pictureformat_4bit 0x0400 # define g1m_pictureformat_4bit_rgb 0x0400 /* Calculating the size is trivial. */ # define g1m_picturesize_4bit(W, H) \ ((W) * (H) / 2) # define g1m_picturesize_4bit_rgb(W, H) \ g1m_picturesize_4bit(W, H) /* ************************************************************************** */ /* 4-bit code format */ /* ************************************************************************** */ /* In this encoding, each nibble for a pixel represents one of the color codes * defined in `libg1m/color.h`. */ # define g1m_pictureformat_4bit_code 0x0410 /* The size is calculated the same way as previously. */ # define g1m_picturesize_4bit_code(W, H) \ g1m_picturesize_4bit(W, H) /* ************************************************************************** */ /* Quad-monochrome VRAM formats */ /* ************************************************************************** */ /* This format is used by old CASIO models. It is made of four monochrome * pictures (no need for fill bits), where the palettes are: * - for the `color` variant: [orange, green, blue, white (bg)] * - for the `mono` variant: [(unused), (unused), black, white (bg)] */ # define g1m_pictureformat_4bit_color 0x0420 # define g1m_pictureformat_4bit_mono 0x0421 /* Just multiply the size of a VRAM by four. */ # define g1m_picturesize_4bit_color(W, H) \ (4 * g1m_picturesize_1bit_old(W, H)) # define g1m_picturesize_4bit_mono(W, H) \ g1m_picturesize_4bit_color(W, H) /* ************************************************************************** */ /* 16-bit R5G6B5 format */ /* ************************************************************************** */ /* This is the format of the Prizm's VRAM. Each pixel is two bytes long, * the first five bits represent the high five (clap!) bits of the red part, * the next six bits represent the high six bits of the green part, * the last five bits represent the high five (re-clap!) bits of the blue * part. */ # define g1m_pictureformat_16bit 0x1000 /* Two bytes per pixel. */ # define g1m_picturesize_16bit(W, H) \ ((W) * (H) * 2) #endif /* LIBG1M_PICTURE_H */