Added --no-plot and --save-plot to entropy.py.

src/binwalk/modules/entropy.py

+import os
 import math
+import binwalk.core.common
 from binwalk.core.module import Module, Option, Kwarg
 
 class Entropy(Module):
@@ -9,6 +11,9 @@ class Entropy(Module):
 	XUNITS = 'B'
 	YUNITS = 'E'
 
+	FILE_WIDTH = 1024
+	FILE_FORMAT = 'png'
+
 	TITLE = "Entropy"
 
 	CLI = [
@@ -16,16 +21,32 @@ class Entropy(Module):
 				   long='entropy',
 				   kwargs={'enabled' : True},
 				   description='Calculate file entropy'),
+			Option(short='J',
+				   long='save-plot',
+				   kwargs={'save_plot' : True},
+				   description='Save plot as a PNG (implied if multiple files are specified)'),
+			Option(short='N',
+				   long='no-plot',
+				   kwargs={'do_plot' : False},
+				   description='Do not generate an entropy plot graph'),
 	]
 
 	KWARGS = [
 			Kwarg(name='enabled', default=False),
+			Kwarg(name='save_plot', default=False),
+			Kwarg(name='do_plot', default=True),
 			Kwarg(name='block_size', default=1024),
 	]
 
 	def init(self):
+		self.HEADER[-1] = "ENTROPY"
+
 		self.entropy_results = {}
 		self.algorithm = self.shannon
+
+		if len(self.config.target_files) > 1:
+			self.save_plot = True
+
 		if self.config.block:
 			self.block_size = self.config.block
 
@@ -52,7 +73,8 @@ class Entropy(Module):
 				r = self.result(offset=(file_offset + i), file=fp, entropy=entropy, description=("%f" % entropy))
 				i += self.block_size
 
-		self.plot_entropy(fp.name)
+		if self.do_plot:
+			self.plot_entropy(fp.name)
 
 	def shannon(self, data):
 		'''
@@ -81,7 +103,7 @@ class Entropy(Module):
 
 		return e
 
-	def plot_entropy(self, title):
+	def plot_entropy(self, fname):
 		import numpy as np
 		import pyqtgraph as pg
 		from pyqtgraph.Qt import QtCore, QtGui
@@ -93,11 +115,16 @@ class Entropy(Module):
 			x.append(r.offset)
 			y.append(r.entropy)
 
-		plt = pg.plot(title=title, clear=True)
+		plt = pg.plot(title=fname, clear=True)
 
 		plt.plot(x, y, pen='y') #pen='b'
 
-		plt.setLabel('left', self.YLABEL, units=self.YUNITS)
-		plt.setLabel('bottom', self.XLABEL, units=self.XUNITS)
-		QtGui.QApplication.instance().exec_()
+		if self.save_plot:
+			exporter = pg.exporters.ImageExporter.ImageExporter(plt.plotItem)
+			exporter.parameters()['width'] = self.FILE_WIDTH
+			exporter.export(binwalk.core.common.unique_file_name(os.path.basename(fname), self.FILE_FORMAT))
+		else:
+			plt.setLabel('left', self.YLABEL, units=self.YUNITS)
+			plt.setLabel('bottom', self.XLABEL, units=self.XUNITS)
+			QtGui.QApplication.instance().exec_()