fix access to png width and height in nbconvert html basic template

IPython/nbconvert/templates/html/basic.tpl

@@ -1,192 +1,192 b''
 {%- extends 'display_priority.tpl' -%}
 
 
 {% block codecell %}
 <div class="cell border-box-sizing code_cell rendered">
 {{ super() }}
 </div>
 {%- endblock codecell %}
 
 {% block input_group -%}
 <div class="input">
 {{ super() }}
 </div>
 {% endblock input_group %}
 
 {% block output_group %}
 <div class="output_wrapper">
 <div class="output">
 {{ super() }}
 </div>
 </div>
 {% endblock output_group %}
 
 {% block in_prompt -%}
 <div class="prompt input_prompt">
 {%- if cell.execution_count is defined -%}
 In&nbsp;[{{ cell.execution_count|replace(None, "&nbsp;") }}]:
 {%- else -%}
 In&nbsp;[&nbsp;]:
 {%- endif -%}
 </div>
 {%- endblock in_prompt %}
 
 {% block empty_in_prompt -%}
 <div class="prompt input_prompt">
 </div>
 {%- endblock empty_in_prompt %}
 
 {# 
   output_prompt doesn't do anything in HTML,
   because there is a prompt div in each output area (see output block)
 #}
 {% block output_prompt %}
 {% endblock output_prompt %}
 
 {% block input %}
 <div class="inner_cell">
     <div class="input_area">
 {{ cell.source | highlight_code(metadata=cell.metadata) }}
 </div>
 </div>
 {%- endblock input %}
 
 {% block output %}
 <div class="output_area">
 {%- if output.output_type == 'execute_result' -%}
     <div class="prompt output_prompt">
 {%- if cell.execution_count is defined -%}
     Out[{{ cell.execution_count|replace(None, "&nbsp;") }}]:
 {%- else -%}
     Out[&nbsp;]:
 {%- endif -%}
 {%- else -%}
     <div class="prompt">
 {%- endif -%}
     </div>
 {{ super() }}
 </div>
 {% endblock output %}
 
 {% block markdowncell scoped %}
 <div class="cell border-box-sizing text_cell rendered">
 {{ self.empty_in_prompt() }}
 <div class="inner_cell">
 <div class="text_cell_render border-box-sizing rendered_html">
 {{ cell.source  | markdown2html | strip_files_prefix }}
 </div>
 </div>
 </div>
 {%- endblock markdowncell %}
 
 {% block unknowncell scoped %}
 unknown type  {{ cell.type }}
 {% endblock unknowncell %}
 
 {% block execute_result -%}
 {%- set extra_class="output_execute_result" -%}
 {% block data_priority scoped %}
 {{ super() }}
 {% endblock %}
 {%- set extra_class="" -%}
 {%- endblock execute_result %}
 
 {% block stream_stdout -%}
 <div class="output_subarea output_stream output_stdout output_text">
 <pre>
 {{- output.text | ansi2html -}}
 </pre>
 </div>
 {%- endblock stream_stdout %}
 
 {% block stream_stderr -%}
 <div class="output_subarea output_stream output_stderr output_text">
 <pre>
 {{- output.text | ansi2html -}}
 </pre>
 </div>
 {%- endblock stream_stderr %}
 
 {% block data_svg scoped -%}
 <div class="output_svg output_subarea {{extra_class}}">
 {%- if output.svg_filename %}
 <img src="{{output.svg_filename | posix_path}}"
 {%- else %}
 {{ output.data['image/svg+xml'] }}
 {%- endif %}
 </div>
 {%- endblock data_svg %}
 
 {% block data_html scoped -%}
 <div class="output_html rendered_html output_subarea {{extra_class}}">
 {{ output.data['text/html'] }}
 </div>
 {%- endblock data_html %}
 
 {% block data_png scoped %}
 <div class="output_png output_subarea {{extra_class}}">
 {%- if 'image/png' in output.metadata.get('filenames', {}) %}
 <img src="{{output.metadata.filenames['image/png'] | posix_path}}"
 {%- else %}
 <img src="data:image/png;base64,{{ output.data['image/png'] }}"
 {%- endif %}
 {%- if 'width' in output.metadata.get('image/png', {}) %}
-width={{output.metadata['png']['width']}}
+width={{output.metadata['image/png']['width']}}
 {%- endif %}
 {%- if 'height' in output.metadata.get('image/png', {}) %}
-height={{output.metadata['png']['height']}}
+height={{output.metadata['image/png']['height']}}
 {%- endif %}
 >
 </div>
 {%- endblock data_png %}
 
 {% block data_jpg scoped %}
 <div class="output_jpeg output_subarea {{extra_class}}">
 {%- if 'image/jpeg' in output.metadata.get('filenames', {}) %}
 <img src="{{output.metadata.filenames['image/jpeg'] | posix_path}}"
 {%- else %}
 <img src="data:image/jpeg;base64,{{ output.data['image/jpeg'] }}"
 {%- endif %}
 {%- if 'width' in output.metadata.get('image/jpeg', {}) %}
 width={{output.metadata['image/jpeg']['width']}}
 {%- endif %}
 {%- if 'height' in output.metadata.get('image/jpeg', {}) %}
 height={{output.metadata['image/jpeg']['height']}}
 {%- endif %}
 >
 </div>
 {%- endblock data_jpg %}
 
 {% block data_latex scoped %}
 <div class="output_latex output_subarea {{extra_class}}">
 {{ output.data['text/latex'] }}
 </div>
 {%- endblock data_latex %}
 
 {% block error -%}
 <div class="output_subarea output_text output_error">
 <pre>
 {{- super() -}}
 </pre>
 </div>
 {%- endblock error %}
 
 {%- block traceback_line %}
 {{ line | ansi2html }}
 {%- endblock traceback_line %}
 
 {%- block data_text scoped %}
 <div class="output_text output_subarea {{extra_class}}">
 <pre>
 {{- output.data['text/plain'] | ansi2html -}}
 </pre>
 </div>
 {%- endblock -%}
 
 {%- block data_javascript scoped %}
 <div class="output_subarea output_javascript {{extra_class}}">
 <script type="text/javascript">
 {{ output.data['text/javascript'] }}
 </script>
 </div>
 {%- endblock -%}