Sakurai/pdf.js
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

cleanup DCTStream rendering code a tad

Browse Source
This commit is contained in:
Andreas Gal 2011-06-20 19:36:40 -04:00
parent 6ae70b4421
commit 28eba6d10e
1 changed files with 18 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
pdf.js
View File

@ -48,6 +48,14 @@ function shadow(obj, prop, value) {
return value;
}
function bytesToString(bytes) {
var str = "";
var length = bytes.length;
for (var n = 0; n < length; ++n)
str += String.fromCharCode(bytes[n]);
return str;
}
var Stream = (function() {
function constructor(arrayBuffer, start, length, dict) {
this.bytes = Uint8Array(arrayBuffer);
@ -518,26 +526,20 @@ 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() {
function constructor(bytes, dict) {
// TODO per poppler, some images may have "junk" before that need to be removed
this.bytes = bytes;
// TODO: per poppler, some images may have "junk" before that need to be removed
this.dict = dict;
// create DOM image
var buffer = "", i, n = bytes.length;
for (i = 0; i < n; ++i) {
buffer += String.fromCharCode(bytes[i]);
}
var img = new Image();
img.src = "data:image/jpeg;base64," + window.btoa(buffer);
img.src = "data:image/jpeg;base64," + window.btoa(bytesToString(bytes));
this.domImage = img;
}
constructor.prototype = {
getChar: function() {
TODO("read direct pixels data");
},
getImage: function() {
return this.domImage;
}
@ -2441,7 +2443,7 @@ var CanvasGraphics = (function() {
Fonts.active = fontName;
}
if (!fontName) {
// fontDescriptor is not available, fallback to default font (TODO ?)
// TODO: fontDescriptor is not available, fallback to default font
this.current.fontSize = size;
this.ctx.font = this.current.fontSize + 'px sans-serif';
return;
@ -2854,7 +2856,10 @@ var CanvasGraphics = (function() {
// scale the image to the unit square
ctx.scale(1/w, -1/h);
if (image instanceof JpegStream) {
// If the platform can render the image format directly, the
// stream has a getImage property which directly returns a
// suitable DOM Image object.
if (image.getImage) {
var domImage = image.getImage();
ctx.drawImage(domImage, 0, 0, domImage.width, domImage.height,
0, -h, w, h);