nimPNG/tester/testSuite.nim

89 lines
2.2 KiB
Nim

import streams, os, strutils, nimPNG
type
BMP = ref object
width, height: int
data: string
proc writeWORD(s: Stream, val: int) =
let word = val.int16
s.write(word)
proc writeDWORD(s: Stream, val: int) =
let dword = val.int32
s.write(dword)
proc newBMP(w, h: int): BMP =
new(result)
result.width = w
result.height = h
result.data = newString(w * h * 3)
proc write(s: Stream, bmp: BMP) =
let stride = 4 * ((bmp.width * 24 + 31) div 32)
let imageData = stride * bmp.height
let offset = 54
var fileSize = imageData + offset
s.writeWORD(19778)
s.writeDWORD(fileSize)
s.writeWORD(0)
s.writeWORD(0)
s.writeDWORD(offset)
s.writeDWORD(40)
s.writeDWORD(bmp.width)
s.writeDWORD(bmp.height)
s.writeWORD(1)
s.writeWORD(24)
s.writeDWORD(0)
s.writeDWORD(imageData)
s.writeDWORD(3780)
s.writeDWORD(3780)
s.writeDWORD(0)
s.writeDWORD(0)
let bytesPerRow = bmp.width * 3
let paddingLen = stride - bytesPerRow
let padding = if paddingLen > 0: newString(paddingLen) else: nil
for i in 0..bmp.height-1:
s.writeData(addr(bmp.data[i * bytesPerRow]), bytesPerRow)
if paddingLen > 0: s.write(padding)
proc loadPNG(fileName: string): BMP =
var settings = makePNGDecoder()
settings.readTextChunks = true
var png = loadPNG24(fileName, settings)
if png == nil: return nil
let size = png.width * png.height
result = newBMP(png.width, png.height)
for i in 0..size-1:
let px = i * 3
result.data[px] = png.data[px]
result.data[px + 1] = png.data[px + 1]
result.data[px + 2] = png.data[px + 2]
proc write(bmp: BMP): string =
var s = newStringStream()
s.write(bmp)
result = s.data
proc convert(dir: string) =
for fileName in walkDirRec(dir, {pcFile}):
let path = splitFile(fileName)
if path.ext.len() == 0: continue
let ext = toLowerAscii(path.ext)
if ext != ".png": continue
if path.name[0] == 'x': continue
let bmpName = path.dir & DirSep & path.name & ExtSep & "bmp"
echo fileName, " vs. ", bmpName
var bmp = loadPNG(fileName)
if bmp != nil:
let data1 = bmp.write()
let data2 = readFile(bmpName)
assert data1 == data2
convert(".." & DirSep & "suite")