HEVC to H264 conversion bitrate

I am converting HEVC video to H264 video using AVFoundation APIs. However I have two problems:
  1. How do I detect the encoder used in the input file using AVFoundation?

  2. How do I calculate the bitrate of the output H264 file that matches the quality of input HEVC file? Need to pass this bitrate to AVAssetWriter compression settings dictionary.

HEVC to H264 conversion bitrate
 
 
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