Smart transcoding

Blue Droplet Video uses a technique called 'smart transcoding'. This involves interrogating the file for information and utilising this information to improve the quality of the output.

• Transcoding always reduces quality to some extent because compression artifacts are cumulative. For both the audio and video streams, there are conditions that when met, allow the stream to 'passthrough' without being transcoded.
  • Audio stream
    • target codec is the same as source
    • target bitrate is greater than or equal to source
    • target channel count is greater than or equal to source
    • target sample rate is greater than or equal to source
  • Video stream
    • target codec is the same as source
    • target bitrate is greater than or equal to source
    • target width is greater than or equal to source
    • target frame rate is greater than or equal to source
• If video transcoding does occur, some modifications are made to the transcoding parameters to improve the result:
  • Videos are never upscaled - this would only reduce quality and bitrate value.
  • The frame rate is never increased (unless the codec demands it) - this only serves to make the video less smooth and can also reduce bitrate value.