Move extracted files into their own subdir

IPython/nbconvert/nbconvertapp.py

@@ -188,6 +188,7 b' class NbConvertApp(BaseIPythonApplication):'
             notebook_name = basename[:basename.rfind('.')]
             resources = {}
             resources['unique_key'] = notebook_name
+            resources['output_files_dir'] = '%s_files' % notebook_name
 
             #Try to export
             try:

IPython/nbconvert/transformers/extractfigure.py

@@ -15,6 +15,7 b" notebook file. The extracted figures are returned in the 'resources' dictionary"
 
 import base64
 import sys
+import os
 
 from IPython.utils.traitlets import Unicode
 from .base import Transformer
@@ -50,8 +51,10 b' class ExtractFigureTransformer(Transformer):'
         """
 
         #Get the unique key from the resource dict if it exists.  If it does not 
-        #exist, use 'figure' as the default.
+        #exist, use 'figure' as the default.  Also, get files directory if it
+        #has been specified
         unique_key = resources.get('unique_key', 'figure')
+        output_files_dir = resources.get('output_files_dir', None)
         
         #Make sure figures key exists
         if not 'figures' in resources:
@@ -77,7 +80,7 b' class ExtractFigureTransformer(Transformer):'
                         data = data.encode("UTF-8")
                     
                     #Build a figure name
-                    figure_name = self.figure_filename_template.format( 
+                    filename = self.figure_filename_template.format( 
                                     unique_key=unique_key,
                                     cell_index=cell_index,
                                     index=index,
@@ -87,10 +90,12 b' class ExtractFigureTransformer(Transformer):'
                     #   cell.outputs[i].svg_filename  ... etc (svg in example)
                     # Where
                     #   cell.outputs[i].svg  contains the data
-                    out[out_type + '_filename'] = figure_name
+                    if output_files_dir is not None:
+                        filename = os.path.join(output_files_dir, filename)
+                    out[out_type + '_filename'] = filename
 
                     #In the resources, make the figure available via
                     #   resources['figures']['filename'] = data
-                    resources['figures'][figure_name] = data
+                    resources['figures'][filename] = data
 
         return cell, resources