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Diffstat (limited to 'tex/context/base/mkiv/lpdf-img.lua')
| -rw-r--r-- | tex/context/base/mkiv/lpdf-img.lua | 1206 |
1 files changed, 1206 insertions, 0 deletions
diff --git a/tex/context/base/mkiv/lpdf-img.lua b/tex/context/base/mkiv/lpdf-img.lua new file mode 100644 index 000000000..aa91f9f22 --- /dev/null +++ b/tex/context/base/mkiv/lpdf-img.lua @@ -0,0 +1,1206 @@ +if not modules then modules = { } end modules ['lpdf-img'] = { + version = 1.001, + comment = "companion to lpdf-ini.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +-- This started as an experiment but has potential for some (cached) optimizations. +-- At some point we can also use it for fonts. For small images performance is ok +-- with pure lua but for bigger images we can use some helpers. Normally in a +-- typesetting workflow non-interlaced images are used. One should convert +-- interlaced images to more efficient non-interlaced ones (ok, we can cache +-- them if needed). +-- +-- The \LUA\ code is slightly optimized so we could have done with less lines if +-- we wanted but best gain a little. The idea is that we collect striped (in stages) +-- so that we can play with substitutions. + +local type = type +local concat, move = table.concat, table.move +local ceil = math.ceil +local char, find = string.char, string.find +local idiv = number.idiv +local band, rshift = bit32.band, bit32.rshift + +local loaddata = io.loaddata +local setmetatableindex = table.setmetatableindex + +local streams = utilities.streams +local openstring = streams.openstring +local readstring = streams.readstring +local readbytetable = streams.readbytetable + +local tobytetable = string.bytetable + +local lpdf = lpdf or { } +local pdfdictionary = lpdf.dictionary +local pdfarray = lpdf.array +local pdfconstant = lpdf.constant +local pdfstring = lpdf.string +local pdfflushstreamobject = lpdf.flushstreamobject +local pdfreference = lpdf.reference + +local pdfmajorversion = lpdf.majorversion +local pdfminorversion = lpdf.minorversion + +local createimage = images.create + +local zlibcompress = flate and flate.zip_compress or zlib.compress +local zlibdecompress = zlib.decompress -- todo + +local trace = false + +local report_jpg = logs.reporter("graphics","jpg") +local report_jp2 = logs.reporter("graphics","jp2") +local report_png = logs.reporter("graphics","png") + +trackers.register("graphics.backend", function(v) trace = v end) + +local injectors = { } +lpdf.injectors = injectors + +local chars = setmetatableindex(function(t,k) -- share this one + local v = (k <= 0 and "\000") or (k >= 255 and "\255") or char(k) + t[k] = v + return v +end) + +do + + function injectors.jpg(specification) + if specification.error then + return + end + local filename = specification.filename + if not filename then + return + end + local colorspace = specification.colorspace or jpg_gray + local decodearray = nil + ----- procset = colorspace == 0 and "image b" or "image c" + if colorspace == 1 then + colorspace = "DeviceGray" + elseif colorspace == 2 then + colorspace = "DeviceRGB" + elseif colorspace == 3 then + colorspace = "DeviceCMYK" + decodearray = pdfarray { 1, 0, 1, 0, 1, 0, 1, 0 } + end + -- todo: set filename + local xsize = specification.xsize + local ysize = specification.ysize + local colordepth = specification.colordepth + local content = loaddata(filename) + local xobject = pdfdictionary { + Type = pdfconstant("XObject"), + Subtype = pdfconstant("Image"), + -- BBox = pdfarray { 0, 0, xsize, ysize }, + Width = xsize, + Height = ysize, + BitsPerComponent = colordepth, + Filter = pdfconstant("DCTDecode"), + ColorSpace = pdfconstant(colorspace), + Decode = decodearray, + Length = #content, -- specification.length + } + specification.attr + if trace then + report_jpg("%s: width %i, height %i, colordepth %i, size %i",filename,xsize,ysize,colordepth,#content) + end + return createimage { + bbox = { 0, 0, specification.width/xsize, specification.height/ysize }, -- mandate + transform = specification.transform, + nolength = true, + nobbox = true, + notype = true, + stream = content, + attr = xobject(), + } + end + +end + +do + + function injectors.jp2(specification) + if specification.error then + return + end + local filename = specification.filename + if not filename then + return + end + -- todo: set filename + local xsize = specification.xsize + local ysize = specification.ysize + local content = loaddata(filename) + local xobject = pdfdictionary { + Type = pdfconstant("XObject"), + Subtype = pdfconstant("Image"), + BBox = pdfarray { 0, 0, xsize, ysize }, + Width = xsize, + Height = ysize, + Filter = pdfconstant("JPXDecode"), + Length = #content, -- specification.length + } + specification.attr + if trace then + report_jp2("%s: width %i, height %i, size %i",filename,xsize,ysize,#content) + end + return createimage { + bbox = { 0, 0, specification.width/xsize, specification.height/ysize }, -- mandate + transform = specification.transform, + nolength = true, + nobbox = true, + notype = true, + stream = content, + attr = xobject(), + } + end + +end + +do + + -- We don't like interlaced files. You can deinterlace them beforehand because otherwise + -- each run you add runtime. Actually, even masked images can best be converted to PDF + -- beforehand. + + -- The amount of code is larger that I like and looks somewhat redundant but we sort of + -- optimize a few combinations that happen often. + + local pngapplyfilter = pnge and pnge.applyfilter + local pngsplitmask = pnge and pnge.splitmask + local pnginterlace = pnge and pnge.interlace + local pngexpand = pnge and pnge.expand + + local filtermask, decodemask, decodestrip, transpose, expand + + local newindex = lua.newindex + local newtable = lua.newtable + + local function newoutput(size) + if newindex then + return newindex(size,0) + end + local t = newtable and newtable(size,0) or { } + for i=1,size do + t[i] = 0 + end + return t + end + + local function convert(t) + if type(t) == "table" then + for i=1,#t do + local ti = t[i] + if ti ~= "" then -- soon gone + t[i] = chars[ti] + end + end + return concat(t) + else + return t + end + end + + local function zero(t,k) + return 0 + end + + local function applyfilter(t,xsize,ysize,bpp) + local len = xsize * bpp + 1 + local n = 1 + local m = len - 1 + for i=1,ysize do + local filter = t[n] + t[n] = "" + if filter == 0 then + elseif filter == 1 then + for j=n+bpp+1,n+m do + t[j] = (t[j] + t[j-bpp]) % 256 + end + elseif filter == 2 then + for j=n+1,n+m do + t[j] = (t[j] + t[j-len]) % 256 + end + elseif filter == 3 then + for j=n+1,n+bpp do + t[j] = (t[j] + idiv(t[j-len],2)) % 256 + end + for j=n+bpp+1,n+m do + t[j] = (t[j] + idiv(t[j-bpp] + t[j-len],2)) % 256 + end + elseif filter == 4 then + for j=n+1,n+bpp do + local p = j - len + local b = t[p] + if b > 0 then + t[j] = (t[j] + b) % 256 + end + end + for j=n+bpp+1,n+m do + local p = j - len + local a = t[j-bpp] + local b = t[p] + local c = t[p-bpp] + local pa = b - c + local pb = a - c + local pc = pa + pb + if pa < 0 then pa = - pa end + if pb < 0 then pb = - pb end + if pc < 0 then pc = - pc end + t[j] = (t[j] + ((pa <= pb and pa <= pc and a) or (pb <= pc and b) or c)) % 256 + end + end + n = n + len + end + return t + end + + local filtermask_l = function (content,xsize,ysize,colordepth,colorspace,hasfilter) + local mask = { } + local bytes = colordepth == 16 and 2 or 1 + local bpp = colorspace == "DeviceRGB" and 3 or 1 + local length = #content + local size = ysize * xsize * ((bpp+1)*bytes + (hasfilter and 1 or 0)) + local n = 1 + local l = 1 + if bytes == 2 then + if bpp == 1 then + for i=1,ysize do + if hasfilter then + content[n] = "" ; n = n + 1 + end + for j=1,xsize do + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + mask[l] = chars[content[n]] ; l = l + 1 + content[n] = "" ; n = n + 1 + mask[l] = chars[content[n]] ; l = l + 1 + content[n] = "" ; n = n + 1 + end + end + elseif bpp == 3 then + for i=1,ysize do + if hasfilter then + content[n] = "" ; n = n + 1 + end + for j=1,xsize do + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + mask[l] = chars[content[n]] ; l = l + 1 + content[n] = "" ; n = n + 1 + mask[l] = chars[content[n]] ; l = l + 1 + content[n] = "" ; n = n + 1 + end + end + else + return "", "" + end + else + if bpp == 1 then + for i=1,ysize do + if hasfilter then + content[n] = "" ; n = n + 1 + end + for j=1,xsize do + content[n] = chars[content[n]] ; n = n + 1 + mask[l] = chars[content[n]] ; l = l + 1 + content[n] = "" ; n = n + 1 + end + end + elseif bpp == 3 then + for i=1,ysize do + if hasfilter then + content[n] = "" ; n = n + 1 + end + for j=1,xsize do + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + content[n] = chars[content[n]] ; n = n + 1 + mask[l] = chars[content[n]] ; l = l + 1 + content[n] = "" ; n = n + 1 + end + end + else + return "", "" + end + end + return concat(content), concat(mask) + end + + local decodemask_l = function(content,xsize,ysize,colordepth,colorspace) + local bytes = colordepth == 16 and 2 or 1 + local bpp = colorspace == "DeviceRGB" and 3 or 1 + local slice = bytes*(bpp+1) + local length = #content + local size = ysize * xsize * ((bpp+1)*bytes + 1) -- assume filter + content = openstring(content) + content = readbytetable(content,length) + setmetatableindex(content,zero) + applyfilter(content,xsize,ysize,slice) + content, mask = filtermask(content,xsize,ysize,colordepth,colorspace,true) + return content, mask + end + + local filtermask_c = function(content,xsize,ysize,colordepth,colorspace) + local bytes = colordepth == 16 and 2 or 1 + local bpp = colorspace == "DeviceRGB" and 3 or 1 + return pngsplitmask(content,xsize,ysize,bpp,bytes) + end + + local decodemask_c = function(content,xsize,ysize,colordepth,colorspace) + local mask = true + local filter = false + local bytes = colordepth == 16 and 2 or 1 + local bpp = colorspace == "DeviceRGB" and 3 or 1 + local slice = bytes * (bpp + 1) -- always a mask + content = pngapplyfilter(content,xsize,ysize,slice) + return pngsplitmask(content,xsize,ysize,bpp,bytes,mask,filter) + end + + local function decodestrip_l(s,nx,ny,slice) + local input = readbytetable(s,ny*(nx*slice+1)) + setmetatableindex(input,zero) + applyfilter(input,nx,ny,slice) + return input, true + end + + local function decodestrip_c(s,nx,ny,slice) + local input = readstring(s,ny*(nx*slice+1)) + input = pngapplyfilter(input,nx,ny,slice) + return input, false + end + + local xstart = { 0, 4, 0, 2, 0, 1, 0 } + local ystart = { 0, 0, 4, 0, 2, 0, 1 } + local xstep = { 8, 8, 4, 4, 2, 2, 1 } + local ystep = { 8, 8, 8, 4, 4, 2, 2 } + + local xblock = { 8, 4, 4, 2, 2, 1, 1 } + local yblock = { 8, 8, 4, 4, 2, 2, 1 } + + local function transpose_l(xsize,ysize,slice,pass,input,output,filter) + local xstart = xstart[pass] + local xstep = xstep[pass] + local ystart = ystart[pass] + local ystep = ystep[pass] + local nx = idiv(xsize + xstep - xstart - 1,xstep) + local ny = idiv(ysize + ystep - ystart - 1,ystep) + local offset = filter and 1 or 0 + local xstep = xstep * slice + local xstart = xstart * slice + local xsize = xsize * slice + local target = ystart * xsize + xstart + 1 + local ystep = ystep * xsize + local start = 1 + local plus = nx * xstep + local step = plus - xstep + if not output then + output = newoutput(xsize*(parts or slice)*ysize) + end + if slice == 1 then + for j=0,ny-1 do + start = start + offset + local target = target + j * ystep + for target=target,target+step,xstep do + output[target] = input[start] + start = start + slice + end + end + elseif slice == 2 then + for j=0,ny-1 do + start = start + offset + local target = target + j * ystep + for target=target,target+step,xstep do + output[target] = input[start] + output[target+1] = input[start+1] + start = start + slice + end + end + elseif slice == 3 then + for j=0,ny-1 do + start = start + offset + local target = target + j * ystep + for target=target,target+step,xstep do + output[target] = input[start] + output[target+1] = input[start+1] + output[target+2] = input[start+2] + start = start + slice + end + end + elseif slice == 4 then + for j=0,ny-1 do + start = start + offset + local target = target + j * ystep + for target=target,target+step,xstep do + output[target] = input[start] + output[target+1] = input[start+1] + output[target+2] = input[start+2] + output[target+3] = input[start+3] + start = start + slice + end + end + else + local delta = slice - 1 + for j=0,ny-1 do + start = start + offset + local target = target + j * ystep + for target=target,target+step,xstep do + move(input,start,start+delta,target,output) + start = start + slice + end + end + end + return output; + end + + local transpose_c = pnginterlace + + -- print(band(rshift(v,4),0x03),extract(v,4,2)) + -- print(band(rshift(v,6),0x03),extract(v,6,2)) + + local function expand_l(t,xsize,ysize,parts,run,factor,filter) + local size = ysize * xsize + 1 -- a bit of overshoot, needs testing, probably a few bytes us ok + local xline = filter and (run+1) or run + local f = filter and 1 or 0 + local l = xline - 1 + local n = 1 + local o = newoutput(size) + local k = 0 + if factor then + if parts == 4 then + for i=1,ysize do + for j=n+f,n+l do + local v = t[j] + if v == 0 then + k = k + 2 + else + k = k + 1 ; o[k] = extract4(v,4) * 0x11 + k = k + 1 ; o[k] = extract4(v,0) * 0x11 + end + end + k = i * xsize + n = n + xline + end + elseif parts == 2 then + for i=1,ysize do + for j=n+f,n+l do + local v = t[j] + if v == 0 then + k = k + 4 + else + k = k + 1 ; o[k] = extract2(v,6) * 0x55 + k = k + 1 ; o[k] = extract2(v,4) * 0x55 + k = k + 1 ; o[k] = extract2(v,2) * 0x55 + k = k + 1 ; o[k] = extract2(v,0) * 0x55 + end + end + k = i * xsize + n = n + xline + end + else + for i=1,ysize do + for j=n+f,n+l do + local v = t[j] + if v == 0 then + k = k + 8 + else + k = k + 1 ; if band(v,0x80) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,7) * 0xFF + k = k + 1 ; if band(v,0x40) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,6) * 0xFF + k = k + 1 ; if band(v,0x20) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,5) * 0xFF + k = k + 1 ; if band(v,0x10) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,4) * 0xFF + k = k + 1 ; if band(v,0x08) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,3) * 0xFF + k = k + 1 ; if band(v,0x04) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,2) * 0xFF + k = k + 1 ; if band(v,0x02) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,1) * 0xFF + k = k + 1 ; if band(v,0x01) ~= 0 then o[k] = 0xFF end -- o[k] = extract1(v,0) * 0xFF + end + end + k = i * xsize + n = n + xline + end + end + else + if parts == 4 then + for i=1,ysize do + for j=n+f,n+l do + local v = t[j] + if v == 0 then + k = k + 2 + else + k = k + 1 ; o[k] = extract4(v,4) + k = k + 1 ; o[k] = extract4(v,0) + end + end + k = i * xsize + n = n + xline + end + elseif parts == 2 then + for i=1,ysize do + for j=n+f,n+l do + local v = t[j] + if v == 0 then + k = k + 4 + else + k = k + 1 ; o[k] = extract2(v,6) + k = k + 1 ; o[k] = extract2(v,4) + k = k + 1 ; o[k] = extract2(v,2) + k = k + 1 ; o[k] = extract2(v,0) + end + end + k = i * xsize + n = n + xline + end + else + for i=1,ysize do + for j=n+f,n+l do + local v = t[j] + if v == 0 then + k = k + 8 + else + k = k + 1 ; if band(v,0x80) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,7) + k = k + 1 ; if band(v,0x40) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,6) + k = k + 1 ; if band(v,0x20) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,5) + k = k + 1 ; if band(v,0x10) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,4) + k = k + 1 ; if band(v,0x08) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,3) + k = k + 1 ; if band(v,0x04) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,2) + k = k + 1 ; if band(v,0x02) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,1) + k = k + 1 ; if band(v,0x01) ~= 0 then o[k] = 1 end -- o[k] = extract1(v,0) + end + end + k = i * xsize + n = n + xline + end + end + end + for i=size,xsize * ysize +1,-1 do + o[i] = nil + end + return o, false + end + + local expand_c = pngexpand + + local function analyze(colordepth,colorspace,palette,mask) + -- return bytes, parts, factor + if palette then + if colordepth == 16 then + return 2, false, false + elseif colordepth == 8 then + return 1, false, false + elseif colordepth == 4 then + return 1, 4, false + elseif colordepth == 2 then + return 1, 2, false + elseif colordepth == 1 then + return 1, 1, false + end + elseif colorspace == "DeviceGray" then + if colordepth == 16 then + return mask and 4 or 2, false, false + elseif colordepth == 8 then + return mask and 2 or 1, false, false + elseif colordepth == 4 then + return 1, 4, true + elseif colordepth == 2 then + return 1, 2, true + elseif colordepth == 1 then + return 1, 1, true + end + else + if colordepth == 16 then + return mask and 8 or 6, false, false + elseif colordepth == 8 then + return mask and 4 or 3, false, false + elseif colordepth == 4 then + return 3, 4, true + elseif colordepth == 2 then + return 3, 2, true + elseif colordepth == 1 then + return 3, 1, true + end + end + return false, false, false + end + + -- 1 6 4 6 2 6 4 6 + -- 7 7 7 7 7 7 7 7 + -- 5 6 5 6 5 6 5 6 + -- 7 7 7 7 7 7 7 7 + -- 3 6 4 6 3 6 4 6 + -- 7 7 7 7 7 7 7 7 + -- 5 6 5 6 5 6 5 6 + -- 7 7 7 7 7 7 7 7 + + local function deinterlace(content,xsize,ysize,colordepth,colorspace,palette,mask) + local slice, parts, factor = analyze(colordepth,colorspace,palette,mask) + if slice then + content = openstring(zlibdecompress(content)) + local filter = false + local output = false + for pass=1,7 do + local xstart = xstart[pass] + local xstep = xstep[pass] + local ystart = ystart[pass] + local ystep = ystep[pass] + local nx = idiv(xsize + xstep - xstart - 1,xstep) + local ny = idiv(ysize + ystep - ystart - 1,ystep) + if nx > 0 and ny > 0 then + local input, filter + if parts then + local nxx = ceil(nx*parts/8) + input, filter = decodestrip(content,nxx,ny,slice) + input, filter = expand(input,nx,ny,parts,nxx,factor,filter) + else + input, filter = decodestrip(content,nx,ny,slice) + end + output = transpose(xsize,ysize,slice,pass,input,output,filter) + end + -- if pass == 3 then + -- break -- still looks ok, could be nice for a preroll + -- end + end + return output, parts and 8 or false + end + end + + -- 1 (palette used), 2 (color used), and 4 (alpha channel used) + + -- paeth: + -- + -- p = a + b - c + -- pa = abs(p - a) => a + b - c - a => b - c + -- pb = abs(p - b) => a + b - c - b => a - c + -- pc = abs(p - c) => a + b - c - c => a + b - c - c => a - c + b - c => pa + pb + + local function full(t,k) local v = "\xFF" t[k] = v return v end + + local function expandvector(transparent) + local s = openstring(transparent) + local n = #transparent + local r = { } + for i=0,n-1 do + r[i] = readstring(s,1) -- readchar + end + setmetatableindex(r,full) + return r + end + + local function createmask_l(content,palette,transparent,xsize,ysize,colordepth,colorspace) + if palette then + local r = expandvector(transparent) + local size = xsize*ysize + local len = ceil(xsize*colordepth/8) + 1 + local o = newoutput(xsize*ysize) + local u = setmetatableindex(zero) + content = zlibdecompress(content) + content = openstring(content) + for i=0,ysize-1 do + local t = readbytetable(content,len) + local k = i * xsize + local filter = t[1] + if filter == 0 then + elseif filter == 1 then + for j=3,len do + t[j] = (t[j] + t[j-1]) % 256 + end + elseif filter == 2 then + for j=2,len do + t[j] = (t[j] + u[j]) % 256 + end + elseif filter == 3 then + local j = 2 + t[j] = (t[j] + idiv(u[j],2)) % 256 + for j=3,len do + t[j] = (t[j] + idiv(t[j-1] + u[j],2)) % 256 + end + elseif filter == 4 then + local j = 2 + local p = j - len + local b = t[p] + if b < 0 then + b = - b + end + if b > 0 then + t[j] = (t[j] + b) % 256 + end + for j=3,len do + local p = j - len + local a = t[j-1] + local b = t[p] + local c = t[p-1] + local pa = b - c + local pb = a - c + local pc = pa + pb + if pa < 0 then pa = - pa end + if pb < 0 then pb = - pb end + if pc < 0 then pc = - pc end + t[j] = (t[j] + ((pa <= pb and pa <= pc and a) or (pb <= pc and b) or c)) % 256 + end + end + if colordepth == 8 then + for j=2,len do + local v = t[j] + k = k + 1 ; o[k] = r[v] + end + elseif colordepth == 4 then + for j=2,len do + local v = t[j] + k = k + 1 ; o[k] = r[extract4(v,4)] + k = k + 1 ; o[k] = r[extract4(v,0)] + end + elseif colordepth == 2 then + for j=2,len do + local v = t[j] + k = k + 1 ; o[k] = r[extract2(v,6)] + k = k + 1 ; o[k] = r[extract2(v,4)] + k = k + 1 ; o[k] = r[extract2(v,2)] + k = k + 1 ; o[k] = r[extract2(v,0)] + end + else + for j=2,len do + local v = t[j] + k = k + 1 ; o[k] = r[extract1(v,7)] + k = k + 1 ; o[k] = r[extract1(v,6)] + k = k + 1 ; o[k] = r[extract1(v,5)] + k = k + 1 ; o[k] = r[extract1(v,4)] + k = k + 1 ; o[k] = r[extract1(v,3)] + k = k + 1 ; o[k] = r[extract1(v,2)] + k = k + 1 ; o[k] = r[extract1(v,1)] + k = k + 1 ; o[k] = r[extract1(v,0)] + end + end + u = t + end + return concat(o,"",1,size) + end + end + + local function createmask_c(content,palette,transparent,xsize,ysize,colordepth,colorspace) + if palette then + local r = expandvector(transparent) + local size = xsize*ysize + local len = ceil(xsize*colordepth/8) + local o = newoutput(size) + content = zlibdecompress(content) + content = pngapplyfilter(content,len,ysize,1) -- nostrip (saves copy) + content = openstring(content) + for i=0,ysize-1 do + local t = readbytetable(content,len) + local k = i * xsize + if colordepth == 8 then + for j=1,len do + local v = t[j] + k = k + 1 ; o[k] = r[v] + end + elseif colordepth == 4 then + for j=1,len do + local v = t[j] + k = k + 1 ; o[k] = r[extract4(v,4)] + k = k + 1 ; o[k] = r[extract4(v,0)] + end + elseif colordepth == 2 then + for j=1,len do + local v = t[j] + k = k + 1 ; o[k] = r[extract2(v,6)] + k = k + 1 ; o[k] = r[extract2(v,4)] + k = k + 1 ; o[k] = r[extract2(v,2)] + k = k + 1 ; o[k] = r[extract2(v,0)] + end + else + for j=1,len do + local v = t[j] + k = k + 1 ; o[k] = r[extract1(v,7)] + k = k + 1 ; o[k] = r[extract1(v,6)] + k = k + 1 ; o[k] = r[extract1(v,5)] + k = k + 1 ; o[k] = r[extract1(v,4)] + k = k + 1 ; o[k] = r[extract1(v,3)] + k = k + 1 ; o[k] = r[extract1(v,2)] + k = k + 1 ; o[k] = r[extract1(v,1)] + k = k + 1 ; o[k] = r[extract1(v,0)] + end + end + end + return concat(o,"",1,size) + end + end + + local function switch(v) + if v then + filtermask = filtermask_l + decodemask = decodemask_l + decodestrip = decodestrip_l + transpose = transpose_l + expand = expand_l + createmask = createmask_l + else + filtermask = filtermask_c + decodemask = decodemask_c + decodestrip = decodestrip_c + transpose = transpose_c + expand = expand_c + createmask = createmask_c + end + end + + if pngapplyfilter then + switch(false) + directives.register("graphics.png.purelua",switch) + else + switch(true) + end + + local alwaysdecode = false + + -- directives.register("graphics.png.decode", function(v) + -- alwaysdecode = v + -- end) + + function injectors.png(specification) +-- inspect(specification) + if specification.error then + return + end + local filename = specification.filename + if not filename then + return + end + local colorspace = specification.colorspace + if not colorspace then + return + end + local interlace = specification.interlace or 0 + if interlace == 1 then + interlace = true + elseif interlace == 0 then + interlace = false + else + report_png("unknown interlacing %i",interlace) + return + end + local tables = specification.tables + if not tables then + return + end + local idat = tables.idat + if not idat then + return + end + local pngfile = io.open(filename,"rb") -- todo: in-mem too + if not pngfile then + return + end + local content = idat(pngfile,true) + tables.idat = false + -- + -- if tables.gama then + -- report_png("ignoring gamma correction") + -- end + -- + local xsize = specification.xsize + local ysize = specification.ysize + local colordepth = specification.colordepth or 8 + local mask = false + local transparent = false + local palette = false + local colors = 1 + if colorspace == 0 then -- gray | image b + colorspace = "DeviceGray" + transparent = true + elseif colorspace == 2 then -- rgb | image c + colorspace = "DeviceRGB" + colors = 3 + transparent = true + elseif colorspace == 3 then -- palette | image c+i + colorspace = "DeviceRGB" + palette = true + transparent = true + elseif colorspace == 4 then -- gray | alpha | image b + colorspace = "DeviceGray" + mask = true + elseif colorspace == 6 then -- rgb | alpha | image c + colorspace = "DeviceRGB" + colors = 3 + mask = true + else + report_png("unknown colorspace %i",colorspace) + return + end + -- + if transparent then + local trns = tables.trns + if trns then + transparent = trns(pngfile,true) + if transparent == "" then + transparent = false + end + tables.trns = false + else + transparent = false + end + end + -- + local decode = alwaysdecode + local major = pdfmajorversion() + local minor = pdfminorversion() + if major > 1 then + -- we're okay + elseif minor < 5 and colordepth == 16 then + report_png("16 bit colordepth not supported in pdf < 1.5") + return + elseif minor < 4 and (mask or transparent) then + report_png("alpha channels not supported in pdf < 1.4") + return + elseif minor < 2 then + report_png("you'd better use a version > 1.2") + return + -- decode = true + end + -- + -- todo: compresslevel (or delegate) + -- + if palette then + local plte = tables.plte + if plte then + palette = plte(pngfile,true) + if palette == "" then + palette = false + end + tables.plte = false + else + palette = false + end + end + -- + if interlace then + local r, p = deinterlace(content,xsize,ysize,colordepth,colorspace,palette,mask) + if not r then + return + end + if p then + colordepth = p + end + if mask then + if not (colordepth == 8 or colordepth == 16) then + report_png("mask can't be split from the image") + return + end -- get rid of bpp: + content, mask = filtermask(r,xsize,ysize,colordepth,colorspace,false) + else + content = convert(r) -- can be in deinterlace if needed + end + content = zlibcompress(content,3) + decode = true + elseif mask then + if not (colordepth == 8 or colordepth == 16) then + report_png("mask can't be split from the image") + return + end + content = zlibdecompress(content) + content, mask = decodemask(content,xsize,ysize,colordepth,colorspace) + content = zlibcompress(content,3) + decode = true -- we don't copy the filter byte + elseif transparent then + -- in test suite + if palette then + mask = createmask(content,palette,transparent,xsize,ysize,colordepth,colorspace) + else + pallette = false + end + elseif decode then + -- this one needs checking + local bytes = analyze(colordepth,colorspace) + if bytes then + content = zlibdecompress(content) + content = applyfilter(content,xsize,ysize,bytes) + content = zlibcompress(content,3) + else + return + end + else + -- print("PASS ON") + end + if palette then + palette = pdfarray { + pdfconstant("Indexed"), + pdfconstant("DeviceRGB"), + idiv(#palette,3), + pdfreference(pdfflushstreamobject(palette)), + } + end + pngfile:close() + local xobject = pdfdictionary { + Type = pdfconstant("XObject"), + Subtype = pdfconstant("Image"), + -- BBox = pdfarray { 0, 0, xsize, ysize }, + Width = xsize, + Height = ysize, + BitsPerComponent = colordepth, + Filter = pdfconstant("FlateDecode"), + ColorSpace = palette or pdfconstant(colorspace), + Length = #content, + } + specification.attr + if mask then + local d = pdfdictionary { + Type = pdfconstant("XObject"), + Subtype = pdfconstant("Image"), + Width = xsize, + Height = ysize, + BitsPerComponent = palette and 8 or colordepth, + ColorSpace = pdfconstant("DeviceGray"), + } + xobject.SMask = pdfreference(pdfflushstreamobject(mask,d())) + end + if not decode then + xobject.DecodeParms = pdfdictionary { + Colors = colors, + Columns = xsize, + BitsPerComponent = colordepth, + Predictor = 15, + } + end + if trace then + report_png("%s: width %i, height %i, colordepth: %i, size: %i, palette %l, mask: %l, transparent %l, decode %l",filename,xsize,ysize,colordepth,#content,palette,mask,transparent,decode) + end + if specification.colorref then + xobject.ColorSpace = pdfreference(specification.colorref) + end + return createimage { + bbox = { 0, 0, specification.width/xsize, specification.height/ysize }, -- mandate + transform = specification.transform, + nolength = true, + nobbox = true, + notype = true, + stream = content, + attr = xobject(), + } + end + +end + +do + + local function pack(specification,what) + local t = { } + local n = 0 + local s = specification.colorspace + local d = specification.data + local x = specification.xsize + local y = specification.ysize + if what == "mask" then + d = specification.mask + s = 1 + end + if s == 1 then + for i=1,y do + local r = d[i] + for j=1,x do + n = n + 1 ; t[n] = chars[r[j]] + end + end + elseif s == 2 then + for i=1,y do + local r = d[i] + for j=1,x do + local c = r[j] + n = n + 1 ; t[n] = chars[c[1]] + n = n + 1 ; t[n] = chars[c[2]] + n = n + 1 ; t[n] = chars[c[3]] + end + end + elseif s == 3 then + for i=1,y do + local r = d[i] + for j=1,x do + local c = r[j] + n = n + 1 ; t[n] = chars[c[1]] + n = n + 1 ; t[n] = chars[c[2]] + n = n + 1 ; t[n] = chars[c[3]] + n = n + 1 ; t[n] = chars[c[4]] + end + end + end + return concat(t) + end + + function injectors.bitmap(specification) + local data = specification.data + if not data then + return + end + local xsize = specification.xsize or 0 + local ysize = specification.ysize or 0 + if xsize == 0 or ysize == 0 then + return + end + local colorspace = specification.colorspace or 1 + if colorspace == 1 then + colorspace = "DeviceGray" + elseif colorspace == 2 then + colorspace = "DeviceRGB" + elseif colorspace == 3 then + colorspace = "DeviceCMYK" + end + local colordepth = (specification.colordepth or 2) == 16 or 8 + local content = pack(specification,"data") + local mask = specification.mask + local xobject = pdfdictionary { + Type = pdfconstant("XObject"), + Subtype = pdfconstant("Image"), + BBox = pdfarray { 0, 0, xsize, ysize }, + Width = xsize, + Height = ysize, + BitsPerComponent = colordepth, + ColorSpace = pdfconstant(colorspace), + Length = #content, -- specification.length + } + if mask then + local d = pdfdictionary { + Type = pdfconstant("XObject"), + Subtype = pdfconstant("Image"), + Width = xsize, + Height = ysize, + BitsPerComponent = colordepth, + ColorSpace = pdfconstant("DeviceGray"), + } + xobject.SMask = pdfreference(pdfflushstreamobject(pack(specification,"mask"),d())) + end + return createimage { + bbox = { 0, 0, specification.width/xsize, specification.height/ysize }, -- mandate + -- nolength = true, + nobbox = true, + notype = true, + stream = content, + attr = xobject(), + } + end + +end + +-- local function validcompression(data) +-- local d = utilities.streams.openstring(data) +-- local b1 = utilities.streams.readbyte(d) +-- local b2 = utilities.streams.readbyte(d) +-- print(b1,b2) +-- if (b1 * 256 + b2) % 31 ~= 0 then +-- return false, "no zlib compressed file" +-- end +-- local method = band(b1,15) +-- if method ~= 8 then +-- return false, "method 8 expected" +-- end +-- local detail = band(rshift(b1,4),15) +-- if detail > 7 then +-- return false, "window 32 expected" +-- end +-- local preset = band(rshift(b2,5),1) +-- if preset ~= 0 then +-- return false, "unexpected preset dictionary" +-- end +-- return true +-- end |