Pull out format normaliser. Fix #18

.eslintrc

@@ -129,7 +129,7 @@
         "generator-star-spacing": 0,
         "guard-for-in": 1,
         "handle-callback-err": 2,
-        "id-length": [2, {"min": 3, "max": 20, "exceptions":["x", "y", "i", "j", "ex", "up"]}],
+        "id-length": [2, {"min": 3, "max": 25, "exceptions":["x", "y", "i", "j", "ex", "up"]}],
         "indent": [1, 2, {"SwitchCase": 1}],
         "init-declarations": 0,
         "key-spacing": [1, { "beforeColon": false, "afterColon": true }],

lib/format-normaliser.js

@@ -0,0 +1,89 @@
+'use strict';
+
+function dePalette(indata, outdata, width, height, palette) {
+  var pxPos = 0;
+  // use values from palette
+  for (var y = 0; y < height; y++) {
+    for (var x = 0; x < width; x++) {
+      var color = palette[indata[pxPos]];
+
+      if (!color) {
+        throw new Error('index ' + indata[pxPos] + ' not in palette');
+      }
+
+      for (var i = 0; i < 4; i++) {
+        outdata[pxPos + i] = color[i];
+      }
+      pxPos += 4;
+    }
+  }
+}
+
+function replaceTransparentColor(indata, outdata, width, height, transColor) {
+  var pxPos = 0;
+  for (var y = 0; y < height; y++) {
+    for (var x = 0; x < width; x++) {
+      var makeTrans = false;
+
+      if (transColor.length === 1) {
+        if (transColor[0] === indata[pxPos]) {
+          makeTrans = true;
+        }
+      }
+      else if (transColor[0] === indata[pxPos] && transColor[1] === indata[pxPos + 1] && transColor[2] === indata[pxPos + 2]) {
+        makeTrans = true;
+      }
+      if (makeTrans) {
+        for (var i = 0; i < 4; i++) {
+          outdata[pxPos + i] = 0;
+        }
+      }
+      pxPos += 4;
+    }
+  }
+}
+
+function scaleDepth(indata, outdata, width, height, depth) {
+  var maxOutSample = 255;
+  var maxInSample = Math.pow(2, depth) - 1;
+  var pxPos = 0;
+
+  for (var y = 0; y < height; y++) {
+    for (var x = 0; x < width; x++) {
+      for (var i = 0; i < 4; i++) {
+        outdata[pxPos + i] = Math.floor((indata[pxPos + i] * maxOutSample) / maxInSample + 0.5);
+      }
+      pxPos += 4;
+    }
+  }
+}
+
+module.exports = function(indata, imageData) {
+
+  var depth = imageData.depth;
+  var width = imageData.width;
+  var height = imageData.height;
+  var colorType = imageData.colorType;
+  var transColor = imageData.transColor;
+  var palette = imageData.palette;
+
+  var outdata = indata; // only different for 16 bits
+
+  if (colorType === 3) { // paletted
+    dePalette(indata, outdata, width, height, palette);
+  }
+  else {
+    if (transColor) {
+      replaceTransparentColor(indata, outdata, width, height, transColor);
+    }
+    // if it needs scaling
+    if (depth !== 8) {
+      // if we need to change the buffer size
+      if (depth === 16) {
+        outdata = new Buffer(width * height * 4);
+      }
+      scaleDepth(indata, outdata, width, height, depth);
+    }
+  }
+  return outdata;
+};

lib/parser-async.js

@@ -1,13 +1,12 @@
 'use strict';
 
-
 var util = require('util');
 var zlib = require('zlib');
 var ChunkStream = require('./chunkstream');
 var FilterAsync = require('./filter-async');
 var Parser = require('./parser');
 var bitmapper = require('./bitmapper');
-
+var formatNormaliser = require('./format-normaliser');
 
 var ParserAsync = module.exports = function(options) {
   ChunkStream.call(this);
@@ -98,7 +97,14 @@ ParserAsync.prototype._complete = function(filteredData, width, height) {
       this._depth,
       this._interlace);
 
-    bitmapData = this._parser.reverseFiltered(bitmapData, this._depth, width, height);
+    // todo not bitmap data any more
+    bitmapData = formatNormaliser(bitmapData, {
+      depth: this._depth, // TODO always store in this format
+      width: width,
+      height: height,
+      colorType: this._parser._colorType,
+      palette: this._parser._palette,
+      transColor: this._parser._transColor });
   }
   catch (ex) {
     this._handleError(ex);

lib/parser-sync.js

@@ -6,6 +6,7 @@ var SyncReader = require('./sync-reader');
 var FilterSync = require('./filter-sync');
 var Parser = require('./parser');
 var bitmapper = require('./bitmapper');
+var formatNormaliser = require('./format-normaliser');
 
 
 var ParserSync = module.exports = function(buffer, options) {
@@ -33,6 +34,10 @@ var ParserSync = module.exports = function(buffer, options) {
 
   var data = zlib.inflateSync(inflateData);
 
+  if (!data || !data.length) {
+    throw new Error('bad png - invalid inflate data response');
+  }
+
   data = FilterSync.process(
     data,
     this._width, this._height,
@@ -41,13 +46,19 @@ var ParserSync = module.exports = function(buffer, options) {
     this._interlace,
     this._options
   );
-
+// todo do not store _data
   this._data = bitmapper.dataToBitMap(data, this._width, this._height,
     this._bpp,
     this._depth,
     this._interlace);
-  // todo yuck
+
-  this.data = this._parser.reverseFiltered(this._data, this._depth, this._width, this._height);
+  this.data = formatNormaliser(this._data, {
+    depth: this._depth, // TODO always store in this format
+    width: this._width,
+    height: this._height,
+    colorType: this._parser._colorType,
+    palette: this._parser._palette,
+    transColor: this._parser._transColor });
 };
 
 ParserSync.prototype._handleError = function(err) {
@@ -73,5 +84,5 @@ ParserSync.prototype._createData = function(width, height, bpp, depth, interlace
   this._height = height;
   this._depth = depth;
   this._interlace = interlace;
-  return this._data;
+  return this._data; // todo do not return
 };

lib/parser.js

@@ -276,7 +276,6 @@ Parser.prototype._parseIDAT = function(length, data) {
   }
 };
 
-
 Parser.prototype._handleIEND = function(length) {
   this.read(length, this._parseIEND.bind(this));
 };
@@ -289,79 +288,3 @@ Parser.prototype._parseIEND = function(data) {
 
   this.finished();
 };
-
-Parser.prototype.reverseFiltered = function(indata, depth, width, height) {
-
-  var outdata = indata; // only different for 16 bits
-
-  var pxLineLength = width << 2;
-  var x, y, i, pxPos, pxRowPos;
-
-  if (this._colorType === 3) { // paletted
-    //TODO abstract loop?
-    // use values from palette
-    for (y = 0; y < height; y++) {
-      pxRowPos = y * pxLineLength;
-
-      for (x = 0; x < width; x++) {
-        pxPos = pxRowPos + (x << 2);
-        var color = this._palette[indata[pxPos]];
-
-        if (!color) {
-          throw new Error('index ' + indata[pxPos] + ' not in palette');
-        }
-
-        for (i = 0; i < 4; i++) {
-          indata[pxPos + i] = color[i];
-        }
-      }
-    }
-  }
-  else {
-    if (this._transColor) {
-      for (y = 0; y < height; y++) {
-        pxRowPos = y * pxLineLength;
-
-        for (x = 0; x < width; x++) {
-          pxPos = pxRowPos + (x << 2);
-          var makeTrans = false;
-          //console.log(pxPos);
-          if (this._transColor.length === 1) {
-            if (this._transColor[0] === indata[pxPos]) {
-              makeTrans = true;
-            }
-          }
-          else if (this._transColor[0] === indata[pxPos] && this._transColor[1] === indata[pxPos + 1] && this._transColor[2] === indata[pxPos + 2]) {
-            makeTrans = true;
-          }
-          if (makeTrans) {
-            for (i = 0; i < 4; i++) {
-              indata[pxPos + i] = 0;
-            }
-          }
-        }
-      }
-    }
-    if (depth !== 8) {
-      if (depth === 16) {
-        outdata = new Buffer(width * height * 4);
-      }
-      //console.log("adjusting");
-      var maxOutSample = 255;
-      var maxInSample = Math.pow(2, depth) - 1;
-
-      for (y = 0; y < height; y++) {
-        pxRowPos = y * pxLineLength;
-
-        for (x = 0; x < width; x++) {
-          pxPos = pxRowPos + (x << 2);
-          for (i = 0; i < 4; i++) {
-            outdata[pxPos + i] = Math.floor((indata[pxPos + i] * maxOutSample) / maxInSample + 0.5);
-          }
-        }
-      }
-    }
-  }
-  return outdata;
-};
-

lib/png.js

@@ -49,6 +49,11 @@ PNG.sync = PNGSync;
 
 PNG.prototype.pack = function() {
 
+  if (!this.data || !this.data.length) {
+    this.emit('error', 'No data provided');
+    return this;
+  }
+
   process.nextTick(function() {
     this._packer.pack(this.data, this.width, this.height);
   }.bind(this));

test/convert-images.js

@@ -15,9 +15,15 @@ module.exports = function(done) {
 
         var completed = 0;
         var expected = files.length * 2;
-        function complete() {
+        var anyFailures = false;
+        function complete(isSuccessful) {
             completed++;
+            anyFailures = anyFailures || !isSuccessful;
             if (expected === completed) {
+                if (anyFailures) {
+                    process.exit(1);
+                    return;
+                }
                 done();
             }
         }
@@ -41,13 +47,13 @@ module.exports = function(done) {
                     console.log(e.stack);
                 }
                 syncError = true;
-                complete();
+                complete(expectedError);
             }
 
             if (!syncError) {
                 if (expectedError) {
                     console.log("Sync: Error expected, parsed fine ..", file);
-                    complete();
+                    complete(false);
                 } else {
 
                     var outpng = new PNG();
@@ -58,7 +64,7 @@ module.exports = function(done) {
                     outpng.pack()
                       .pipe(fs.createWriteStream(__dirname + '/outsync/' + file)
                         .on("finish", function () {
-                            complete();
+                            complete(true);
                         }));
                 }
             }
@@ -69,7 +75,7 @@ module.exports = function(done) {
                   if (!expectedError) {
                       console.log("Async: Unexpected error parsing.." + file, err);
                   }
-                  complete();
+                  complete(expectedError);
               })
               .on('parsed', function () {
 
@@ -82,11 +88,9 @@ module.exports = function(done) {
                   .pipe(
                     fs.createWriteStream(__dirname + '/out/' + file)
                       .on("finish", function() {
-                          complete();
+                          complete(true);
                       }));
-
               });
-
         });
     });
 }