pdfdraw/index.html at master · flexpaper/pdfdraw · GitHub

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<!DOCTYPE html>
<html>
<head>
    <title></title>
    <script type="text/javascript" src="js/pdf.js"></script>
    <script>
        // gui.App.argv[0] = filename
        // gui.App.argv[1] = format (jpeg/png)
        // gui.App.argv[2] = output folder
		// gui.App.argv[3] = num pages

        // OSX execution sample: /Applications/node-webkit.app/Contents/MacOS/node-webkit . "docs/Paper.pdf" "jpeg" "export"
        // Windows execution sample: pdfdraw.exe "docs/Paper.pdf" "jpeg" "export"

        var gui = require('nw.gui');
        pdfdraw(gui.App.argv[0],gui.App.argv[1],gui.App.argv[2],parseInt(gui.App.argv[3]));
        var fsOut = require('fs');

		// Get the current window
		var win = gui.Window.get();
		win.hide();

        function pdfdraw(pdfFile,format,outputFolder,totalPages){
            PDFJS.disableWorker = true;
            PDFJS.workerSrc = 'js/pdf.worker.js';
            PDFJS.disableRange = true;
            PDFJS.disableAutoFetch = true;
            PDFJS.enableStats = false;
            PDFJS.disableHistory = true;
            PDFJS.verbosity = 5;

            var parameters = {password: ''};
            window.pdfFile = parameters.url = pdfFile.toString();
            parameters.exportResources = false;
			window.pdfFile = window.pdfFile.replace(/\//g,"\\");
			window.pdfFileName = window.pdfFile.substring(window.pdfFile.lastIndexOf("\\")+1);
			window.pagesToConvert = totalPages;
            window.numResolved = 0;

            PDFJS.getDocument(parameters).then(function(pdf) {
                window.numPages = pdf.numPages;
                window.pagePromises = new Array(pdf.numPages);

				if(!window.totalPages)
					window.totalPages = (window.pagesToConvert>-1 && window.pagesToConvert < pdf.numPages)?window.pagesToConvert:pdf.numPages;

                for(var p=0;p<window.totalPages+1;p++){
                    console.log('Rendering page '+p);

                    var pagePromise = window.pagePromises[p] = pdf.getPage(p).then(function(page) {
                        var scale = 1275/page.view[2];
                        var viewport = page.getViewport(scale);

                        //
                        // Prepare canvas using PDF page dimensions
                        //
                        var canvas = document.createElement('canvas');
                        var context = canvas.getContext('2d');

                        canvas.height = viewport.height;
                        canvas.width = viewport.width;

                        var renderContext = {
                            canvasContext: context,
                            viewport: viewport,
                            textLayer: null,
                            continueCallback: function(cont) {
                                cont();
                            }
                        };

                        //
                        // render the page & save to disk
                        //
                        page.render(renderContext).then(function pdfPageRenderCallback() {

                            console.log('Writing page '+page.pageNumber+' to disk');

							var ctx = canvas.getContext('2d');
							var imgData = ctx.getImageData(0,0,canvas.width,canvas.height);
							ctx.globalCompositeOperation = "destination-over";
							ctx.fillStyle = "#ffffff";
							ctx.fillRect(0,0,canvas.width,canvas.height);

                            fsOut.writeFileSync(outputFolder+window.pdfFileName+"_"+page.pageNumber+"."+(format=="jpeg"?"jpg":format), decodeBase64Image(canvas.toDataURL("image/"+format)).data);
                            delete canvas;

                            window.numResolved++;
                            closeWindowCallback();

                        },function pdfPageRenderError(error) {

                        });
                    });
                }
            });
        }

        function closeWindowCallback(){
            if(window.numResolved==window.totalPages-1){
                gui.App.quit();
            }
        }

        function decodeBase64Image(dataString) {
            var matches = dataString.match(/^data:([A-Za-z-+\/]+);base64,(.+)$/),
                    response = {};

            if (matches.length !== 3) {
                return new Error('Invalid input string');
            }

            response.type = matches[1];
            response.data = new Buffer(matches[2], 'base64');

            return response;
        }
    </script>
</head>
<body>
    Converting to PDF to jpeg
</body>
</html>