Sample IMPACT hackathon workflow

Created: 2011-11-14 16:12:10 Last updated: 2012-06-19 10:28:42

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Workflow that implements the Use Case for Group 2 at the IMPACT/Taverna hackathon.

What it does is to take the URL of a TIFF image and compute the Levenshtein difference between the OCR output of the uncompressed version with various ones compressed at various bit rates.

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http://www.myexperiment.org/workflows/2559/download?version=1
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Workflow Components

Authors (1)

Titles (2)

Descriptions (1)

Dependencies (0)

Inputs (3)

Name	Description
InputImage	The URL of the input image. The URL of the input image, as a _string_.
Rate	Number of bits per pixel to use for compression
Language	Language module to use with OCR engine (greatly improves the error rate across all bit-rates).

Processors (7)

Name	Type	Description
Compute_Levenshtein_Distance	beanshell	Script int n = baseline.length(); int m = compressed.length(); if (n == 0) { distance = m; } else if (m == 0) { distance = n; } else { int[] p = new int[n+1]; int[] d = new int[n+1]; int[] _d; int i; int j; char t_j; int cost; for (i = 0; i<=n; i++) { p[i] = i; } for (j = 1; j<=m; j++) { t_j = compressed.charAt(j-1); d[0] = j; for (i=1; i<=n; i++) { cost = baseline.charAt(i-1)==t_j ? 0 : 1; d[i] = Math.min(Math.min(d[i-1]+1, p[i]+1), p[i-1]+cost); } _d = p; p = d; d = _d; } distance = p[n]; }
OCR_Original	workflow
OCR_Compressed	workflow
Compress_Image	workflow
Decompress_Image	workflow
Read_Text_File	localworker	Script BufferedReader getReader (String fileUrl) throws IOException { InputStreamReader reader; try { reader = new FileReader(fileUrl); } catch (FileNotFoundException e) { // try a real URL instead URL url = new URL(fileUrl); reader = new InputStreamReader (url.openStream()); } return new BufferedReader(reader); } StringBuffer sb = new StringBuffer(4000); BufferedReader in = getReader(fileurl); String str; String lineEnding = System.getProperty("line.separator"); while ((str = in.readLine()) != null) { sb.append(str); sb.append(lineEnding); } in.close(); filecontents = sb.toString();
Read_Text_File_2	localworker	Script BufferedReader getReader (String fileUrl) throws IOException { InputStreamReader reader; try { reader = new FileReader(fileUrl); } catch (FileNotFoundException e) { // try a real URL instead URL url = new URL(fileUrl); reader = new InputStreamReader (url.openStream()); } return new BufferedReader(reader); } StringBuffer sb = new StringBuffer(4000); BufferedReader in = getReader(fileurl); String str; String lineEnding = System.getProperty("line.separator"); while ((str = in.readLine()) != null) { sb.append(str); sb.append(lineEnding); } in.close(); filecontents = sb.toString();

Beanshells (1)

Name	Description	Inputs	Outputs
Compute_Levenshtein_Distance		baseline compressed	distance

Outputs (6)

Name	Description
LevenshteinDistance
baselineLog
Compress_Image_Log
EncodingScanningLog
Compressed_Contents
Original_Contents

Datalinks (17)

Source	Sink
Read_Text_File:filecontents	Compute_Levenshtein_Distance:compressed
Read_Text_File_2:filecontents	Compute_Levenshtein_Distance:baseline
InputImage	OCR_Original:InputImage
Language	OCR_Original:Language
Decompress_Image:OutputImage	OCR_Compressed:InputImage
Language	OCR_Compressed:Language
Rate	Compress_Image:CompressionRate
InputImage	Compress_Image:InputImage
Compress_Image:OutputImage	Decompress_Image:InputImage
OCR_Compressed:OutputText	Read_Text_File:fileurl
OCR_Original:OutputText	Read_Text_File_2:fileurl
Compute_Levenshtein_Distance:distance	LevenshteinDistance
OCR_Original:Log	baselineLog
Compress_Image:Log	Compress_Image_Log
OCR_Compressed:Log	EncodingScanningLog
Read_Text_File:filecontents	Compressed_Contents
Read_Text_File_2:filecontents	Original_Contents