# Adaptive field frame controls
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## Description
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The following are the settings and internal algorithms tied to the scan type: 
+ 
+ **Picture Adaptive Field Frame (PAFF)**: This setting is automatically enabled on GPU-enabled versions of Elemental Live and automatically disabled on CPU-only versions.
+ **Macroblock Adaptive Field Frame (MBAFF)**: This setting is automatically enabled on CPU-only versions of Elemental Live and automatically disabled on GPU-enabled versions.
+ **Force Field Pictures**: This field appears only if the codec is H.264 and only affects GPU-enabled versions of Elemental Live. 
  + **Enabled**: All outputs are forced to use PAFF field picture encoding. 
  + **Disabled**: Elemental Live switches between PAFF and MBAFF, depending on the content. 

## Recommendations
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+ **Force Field Pictures **results in a significant reduction in quality so it should only be used if required for compatibility with specific decoders or playback devices. 

## Location of fields
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| Location of field on web interface | Location of tag in XML | 
| --- | --- | 
| Streams – Video > Advanced > Force Field Pictures | stream\_assembly/video\_description/{{codec}}/force\_field\_pictures<br />where {{codec}} is:<br />**h264\_settings** |