andreasgal
commit
4f63d8503f
180
pdf.js
180
pdf.js
@ -526,7 +526,6 @@ var FlateStream = (function() {
|
||||
|
||||
return constructor;
|
||||
})();
|
||||
|
||||
// A JpegStream can't be read directly. We use the platform to render the underlying
|
||||
// JPEG data for us.
|
||||
var JpegStream = (function() {
|
||||
@ -554,49 +553,158 @@ var JpegStream = (function() {
|
||||
|
||||
var PredictorStream = (function() {
|
||||
function constructor(stream, params) {
|
||||
var predictor = params.get("Predictor") || 1;
|
||||
this.predictor = predictor;
|
||||
|
||||
if (predictor <= 1)
|
||||
return stream; // no prediction
|
||||
if (predictor !== 2 && (predictor < 10 || predictor > 15))
|
||||
error("Unsupported predictor");
|
||||
|
||||
if (predictor === 2)
|
||||
this.readRow = this.readRowTiff;
|
||||
else
|
||||
this.readRow = this.readRowPng;
|
||||
|
||||
this.stream = stream;
|
||||
this.dict = stream.dict;
|
||||
this.predictor = params.get("Predictor") || 1;
|
||||
if (this.predictor <= 1) {
|
||||
return stream; // no prediction
|
||||
}
|
||||
if (params.has("EarlyChange")) {
|
||||
error("EarlyChange predictor parameter is not supported");
|
||||
}
|
||||
this.colors = params.get("Colors") || 1;
|
||||
this.bitsPerComponent = params.get("BitsPerComponent") || 8;
|
||||
this.columns = params.get("Columns") || 1;
|
||||
if (this.colors !== 1 || this.bitsPerComponent !== 8) {
|
||||
error("Multi-color and multi-byte predictors are not supported");
|
||||
}
|
||||
if (this.predictor < 10 || this.predictor > 15) {
|
||||
error("Unsupported predictor");
|
||||
}
|
||||
this.currentRow = new Uint8Array(this.columns);
|
||||
this.pos = 0;
|
||||
this.bufferLength = 0;
|
||||
var colors = params.get("Colors") || 1;
|
||||
this.colors = colors;
|
||||
var bits = params.get("BitsPerComponent") || 8;
|
||||
this.bits = bits;
|
||||
var columns = params.get("Columns") || 1;
|
||||
this.columns = columns;
|
||||
|
||||
var pixBytes = (colors * bits + 7) >> 3;
|
||||
this.pixBytes = pixBytes;
|
||||
// add an extra pixByte to represent the pixel left of column 0
|
||||
var rowBytes = ((columns * colors * bits + 7) >> 3) + pixBytes;
|
||||
this.rowBytes = rowBytes;
|
||||
|
||||
this.currentRow = new Uint8Array(rowBytes);
|
||||
this.bufferLength = rowBytes;
|
||||
this.pos = rowBytes;
|
||||
}
|
||||
|
||||
constructor.prototype = {
|
||||
readRow : function() {
|
||||
var lastRow = this.currentRow;
|
||||
readRowTiff : function() {
|
||||
var currentRow = this.currentRow;
|
||||
var rowBytes = this.rowBytes;
|
||||
var pixBytes = this.pixBytes;
|
||||
var bits = this.bits;
|
||||
var colors = this.colors;
|
||||
|
||||
var rawBytes = this.stream.getBytes(rowBytes - pixBytes);
|
||||
|
||||
if (bits === 1) {
|
||||
var inbuf = 0;
|
||||
for (var i = pixBytes, j = 0; i < rowBytes; ++i, ++j) {
|
||||
var c = rawBytes[j];
|
||||
inBuf = (inBuf << 8) | c;
|
||||
// bitwise addition is exclusive or
|
||||
// first shift inBuf and then add
|
||||
currentRow[i] = (c ^ (inBuf >> colors)) & 0xFF;
|
||||
// truncate inBuf (assumes colors < 16)
|
||||
inBuf &= 0xFFFF;
|
||||
}
|
||||
} else if (bits === 8) {
|
||||
for (var i = pixBytes, j = 0; i < rowBytes; ++i, ++j)
|
||||
currentRow[i] = currentRow[i - colors] + rawBytes[j];
|
||||
} else {
|
||||
var compArray = new Uint8Array(colors + 1);
|
||||
var bitMask = (1 << bits) - 1;
|
||||
var inbuf = 0, outbut = 0;
|
||||
var inbits = 0, outbits = 0;
|
||||
var j = 0, k = pixBytes;
|
||||
var columns = this.columns;
|
||||
for (var i = 0; i < columns; ++i) {
|
||||
for (var kk = 0; kk < colors; ++kk) {
|
||||
if (inbits < bits) {
|
||||
inbuf = (inbuf << 8) | (rawBytes[j++] & 0xFF);
|
||||
inbits += 8;
|
||||
}
|
||||
compArray[kk] = (compArray[kk] + (inbuf >>
|
||||
(inbits - bits))) & bitMask;
|
||||
inbits -= bits;
|
||||
outbuf = (outbuf << bits) | compArray[kk];
|
||||
outbits += bits;
|
||||
if (outbits >= 8) {
|
||||
currentRow[k++] = (outbuf >> (outbits - 8)) & 0xFF;
|
||||
outbits -= 8;
|
||||
}
|
||||
}
|
||||
}
|
||||
if (outbits > 0) {
|
||||
currentRow[k++] = (outbuf << (8 - outbits)) +
|
||||
(inbuf & ((1 << (8 - outbits)) - 1))
|
||||
}
|
||||
}
|
||||
this.pos = pixBytes;
|
||||
},
|
||||
readRowPng : function() {
|
||||
var currentRow = this.currentRow;
|
||||
|
||||
var rowBytes = this.rowBytes;
|
||||
var pixBytes = this.pixBytes;
|
||||
|
||||
var predictor = this.stream.getByte();
|
||||
var currentRow = this.stream.getBytes(this.columns), i;
|
||||
var rawBytes = this.stream.getBytes(rowBytes - pixBytes);
|
||||
|
||||
switch (predictor) {
|
||||
case 0:
|
||||
break;
|
||||
case 1:
|
||||
for (var i = pixBytes, j = 0; i < rowBytes; ++i, ++j)
|
||||
currentRow[i] = (currentRow[i - pixBytes] + rawBytes[j]) & 0xFF;
|
||||
break;
|
||||
case 2:
|
||||
for (var i = pixBytes, j = 0; i < rowBytes; ++i, ++j)
|
||||
currentRow[i] = (currentRow[i] + rawBytes[j]) & 0xFF;
|
||||
break;
|
||||
case 3:
|
||||
for (var i = pixBytes, j = 0; i < rowBytes; ++i, ++j)
|
||||
currentRow[i] = (((currentRow[i] + currentRow[i - pixBytes])
|
||||
>> 1) + rawBytes[j]) & 0xFF;
|
||||
break;
|
||||
case 4:
|
||||
// we need to save the up left pixels values. the simplest way
|
||||
// is to create a new buffer
|
||||
var lastRow = currentRow;
|
||||
var currentRow = new Uint8Array(rowBytes);
|
||||
for (var i = pixBytes, j = 0; i < rowBytes; ++i, ++j) {
|
||||
var up = lastRow[i];
|
||||
var upLeft = lastRow[i - pixBytes];
|
||||
var left = currentRow[i - pixBytes];
|
||||
var p = left + up - upLeft;
|
||||
|
||||
var pa = p - left;
|
||||
if (pa < 0)
|
||||
pa = -pa;
|
||||
var pb = p - up;
|
||||
if (pb < 0)
|
||||
pb = -pb;
|
||||
var pc = p - upLeft;
|
||||
if (pc < 0)
|
||||
pc = -pc;
|
||||
|
||||
var c = rawBytes[j];
|
||||
if (pa <= pb && pa <= pc)
|
||||
currentRow[i] = left + c;
|
||||
else if (pb <= pc)
|
||||
currentRow[i] = up + c;
|
||||
else
|
||||
currentRow[i] = upLeft + c;
|
||||
break;
|
||||
this.currentRow = currentRow;
|
||||
}
|
||||
default:
|
||||
error("Unsupported predictor");
|
||||
break;
|
||||
case 0:
|
||||
break;
|
||||
case 2:
|
||||
for (i = 0; i < currentRow.length; ++i) {
|
||||
currentRow[i] = (lastRow[i] + currentRow[i]) & 0xFF;
|
||||
}
|
||||
break;
|
||||
}
|
||||
this.pos = 0;
|
||||
this.bufferLength = currentRow.length;
|
||||
this.currentRow = currentRow;
|
||||
this.pos = pixBytes;
|
||||
},
|
||||
getByte : function() {
|
||||
if (this.pos >= this.bufferLength) {
|
||||
@ -692,11 +800,10 @@ var Dict = (function() {
|
||||
this.map[key] = value;
|
||||
},
|
||||
forEach: function(aCallback) {
|
||||
for (var key in this.map)
|
||||
aCallback(key, this.map[key]);
|
||||
for (var key in this.map)
|
||||
aCallback(key, this.map[key]);
|
||||
}
|
||||
};
|
||||
|
||||
return constructor;
|
||||
})();
|
||||
|
||||
@ -1233,7 +1340,8 @@ var Parser = (function() {
|
||||
if (IsArray(filter)) {
|
||||
var filterArray = filter;
|
||||
var paramsArray = params;
|
||||
for (filter in filterArray) {
|
||||
for (var i = 0, ii = filter.length; i < ii; ++i) {
|
||||
filter = filter[i];
|
||||
if (!IsName(filter))
|
||||
error("Bad filter name");
|
||||
else {
|
||||
@ -3030,8 +3138,6 @@ var CanvasGraphics = (function() {
|
||||
if (maskDecode)
|
||||
TODO("Handle mask decode");
|
||||
// handle matte object
|
||||
} else {
|
||||
smask = null;
|
||||
}
|
||||
|
||||
var tmpCanvas = document.createElement("canvas");
|
||||
@ -3182,6 +3288,8 @@ var ColorSpace = (function() {
|
||||
case "DeviceGray":
|
||||
case "G":
|
||||
this.numComps = 1;
|
||||
case "DeviceRGB":
|
||||
this.numComps = 3;
|
||||
break;
|
||||
}
|
||||
TODO("fill in color space constructor");
|
||||
|
||||
Loading…
Reference in New Issue
Block a user