diff options
Diffstat (limited to 'apps/plugins/lua/include_lua/image_save.lua')
| -rw-r--r-- | apps/plugins/lua/include_lua/image_save.lua | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/apps/plugins/lua/include_lua/image_save.lua b/apps/plugins/lua/include_lua/image_save.lua new file mode 100644 index 0000000000..4735af46d7 --- /dev/null +++ b/apps/plugins/lua/include_lua/image_save.lua @@ -0,0 +1,215 @@ +--[[ Lua Image save +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id$ + * + * Copyright (C) 2017 William Wilgus + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ****************************************************************************/ +]] +-- save(img, path/name) +-- bmp saving derived from rockbox - screendump.c +-- bitdepth is limited by the device +-- eg. device displays greyscale, rgb images are saved greyscale +if not rb.lcd_framebuffer then rb.splash(rb.HZ, "No Support!") return nil end + +do + local rocklib_image = getmetatable(rb.lcd_framebuffer()) + + -- internal constants + local _NIL = nil -- _NIL placeholder + local _points = rocklib_image.points + + -- saves img to file: name + return function(img, name) + local file + local bbuffer = {} -- concat buffer for s_bytes + local fbuffer = {} -- concat buffer for file writes, reused + + local function s_bytesLE(bits, value) + -- bits must be multiples of 8 (sizeof byte) + local byte + local nbytes = bit.rshift(bits, 3) + for b = 1, nbytes do + if value > 0 then + byte = value % 256 + value = (value - byte) / 256 + else + byte = 0 + end + bbuffer[b] = string.char(byte) + end + return table.concat(bbuffer, _NIL, 1, nbytes) + end + + local function s_bytesBE(bits, value) + -- bits must be multiples of 8 (sizeof byte) + local byte + local nbytes = bit.rshift(bits, 3) + for b = nbytes, 1, -1 do + if value > 0 then + byte = value % 256 + value = (value - byte) / 256 + else + byte = 0 + end + bbuffer[b] = string.char(byte) + end + return table.concat(bbuffer, _NIL, 1, nbytes) + end + + local cmp = {["r"] = function(c) return bit.band(bit.rshift(c, 16), 0xFF) end, + ["g"] = function(c) return bit.band(bit.rshift(c, 08), 0xFF) end, + ["b"] = function(c) return bit.band(c, 0xFF) end} + + local function bmp_color(color) + return s_bytesLE(8, cmp.b(color)).. + s_bytesLE(8, cmp.g(color)).. + s_bytesLE(8, cmp.r(color)).. + s_bytesLE(8, 0) .. "" + end -- c_cmp(color, c.r)) + + local function bmp_color_mix(c1, c2, num, den) + -- mixes c1 and c2 as ratio of numerator / denominator + -- used 2x each save results + local bc1, gc1, rc1 = cmp.b(c1), cmp.g(c1), cmp.r(c1) + + return s_bytesLE(8, cmp.b(c2) - bc1 * num / den + bc1).. + s_bytesLE(8, cmp.g(c2) - gc1 * num / den + gc1).. + s_bytesLE(8, cmp.r(c2) - rc1 * num / den + rc1).. + s_bytesLE(8, 0) .. "" + end + + local w, h = img:width(), img:height() + local depth = tonumber(img:__tostring(6)) -- RLI_INFO_DEPTH = 0x6 + local format = tonumber(img:__tostring(7)) -- RLI_INFO_FORMAT = 0x7 + + local bpp, bypl -- bits per pixel, bytes per line + -- bypl, pad rows to a multiple of 4 bytes + if depth <= 4 then + bpp = 8 -- 256 color image + bypl = (w + 3) + elseif depth <= 16 then + bpp = 16 + bypl = (w * 2 + 3) + elseif depth <= 24 then + bpp = 24 + bypl = (w * 3 + 3) + else + bpp = 32 + bypl = (w * 4 + 3) + end + + local linebytes = bit.band(bypl, bit.bnot(3)) + + local bytesperpixel = bit.rshift(bpp, 3) + local headersz = 54 + local imgszpad = h * linebytes + + local compression, n_colors = 0, 0 + local h_ppm, v_ppm = 0x00000EC4, 0x00000EC4 --Pixels Per Meter ~ 96 dpi + + if depth == 16 then + compression = 3 -- BITFIELDS + n_colors = 3 + elseif depth <= 8 then + n_colors = bit.lshift(1, depth) + end + + headersz = headersz + (4 * n_colors) + + file = io.open('/' .. name, "w+") -- overwrite, rb ignores the 'b' flag + + if not file then + rb.splash(rb.HZ, "Error opening /" .. name) + return + end + -- create a bitmap header 'rope' with image details -- concatenated at end + local bmpheader = fbuffer + + bmpheader[01] = "BM" + bmpheader[02] = s_bytesLE(32, headersz + imgszpad) + bmpheader[03] = "\0\0\0\0" -- WORD reserved 1 & 2 + bmpheader[04] = s_bytesLE(32, headersz) -- BITMAPCOREHEADER size + bmpheader[05] = s_bytesLE(32, 40) -- BITMAPINFOHEADER size + + bmpheader[06] = s_bytesLE(32, w) + bmpheader[07] = s_bytesLE(32, h) + bmpheader[08] = "\1\0" -- WORD color planes ALWAYS 1 + bmpheader[09] = s_bytesLE(16, bpp) -- bits/pixel + bmpheader[10] = s_bytesLE(32, compression) + bmpheader[11] = s_bytesLE(32, imgszpad) + bmpheader[12] = s_bytesLE(32, h_ppm) -- biXPelsPerMeter + bmpheader[13] = s_bytesLE(32, v_ppm) -- biYPelsPerMeter + bmpheader[14] = s_bytesLE(32, n_colors) + bmpheader[15] = s_bytesLE(32, n_colors) + + -- Color Table (#n_colors entries) + if depth == 1 then -- assuming positive display + bmpheader[#bmpheader + 1] = bmp_color(0xFFFFFF) + bmpheader[#bmpheader + 1] = bmp_color(0x0) + elseif depth == 2 then + bmpheader[#bmpheader + 1] = bmp_color(0xFFFFFF) + bmpheader[#bmpheader + 1] = bmp_color_mix(0xFFFFFF, 0, 1, 3) + bmpheader[#bmpheader + 1] = bmp_color_mix(0xFFFFFF, 0, 2, 3) + bmpheader[#bmpheader + 1] = bmp_color(0x0) + elseif depth == 16 then + if format == 555 then + -- red bitfield mask + bmpheader[#bmpheader + 1] = s_bytesLE(32, 0x00007C00) + -- green bitfield mask + bmpheader[#bmpheader + 1] = s_bytesLE(32, 0x000003E0) + -- blue bitfield mask + bmpheader[#bmpheader + 1] = s_bytesLE(32, 0x0000001F) + else --565 + -- red bitfield mask + bmpheader[#bmpheader + 1] = s_bytesLE(32, 0x0000F800) + -- green bitfield mask + bmpheader[#bmpheader + 1] = s_bytesLE(32, 0x000007E0) + -- blue bitfield mask + bmpheader[#bmpheader + 1] = s_bytesLE(32, 0x0000001F) + end + end + + file:write(table.concat(fbuffer))-- write the header to the file now + for i=1, #fbuffer do fbuffer[i] = _NIL end -- reuse table + + local imgdata = fbuffer + -- pad rows to a multiple of 4 bytes + local bytesleft = linebytes - (bytesperpixel * w) + local t_data = {} + local fs_bytes_E = s_bytesLE -- default save in Little Endian + + if format == 3553 then -- RGB565SWAPPED + fs_bytes_E = s_bytesBE -- Saves in Big Endian + end + + -- Bitmap lines start at bottom unless biHeight is negative + for point in _points(img, 1, h, w + bytesleft, 1) do + imgdata[#imgdata + 1] = fs_bytes_E(bpp, point or 0) + + if #fbuffer >= 31 then -- buffered write, increase # for performance + file:write(table.concat(fbuffer)) + for i=1, #fbuffer do fbuffer[i] = _NIL end -- reuse table + end + + end + file:write(table.concat(fbuffer)) --write leftovers to file + fbuffer = _NIL + + file:close() + end -- save(img, name) +end |