title: Error trying to decode 4K video using NVDEC
body: <p>I am trying to convert a 4K HEVC MKV file of 70GB into another HECV file but with less size. I am using FFmpeg with Nvidia acceleration but when I execute the following command an error appears:</p>
  
  <pre><code>ffmpeg -y -vsync 0 -hwaccel_device 0 -hwaccel cuvid -c:v hevc_cuvid -i input.mkv -c:a copy -c:v hevc_nvenc -preset slow -b:v 10M -bufsize 10M -maxrate 15M -qmin 0 -g 250 -bf 2 -temporal-aq 1 -rc-lookahead 20 -i_qfactor 0.75 -b_qfactor 1.1 output.mkv
  </code></pre>
  
  <p>The error is: </p>
  
  <pre><code>[hevc_nvenc @ 0000021036b0d000] Provided device doesn't support required NVENC features
  Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
  </code></pre>
  
  <p>The video file has these details: </p>
  
  <p><a href="https://i.stack.imgur.com/C6Bv8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/C6Bv8.png" alt="enter image description here"></a></p>
  
  <p>It seems that FFmpeg cannot recognize my GPU as a supported device to decode but I have read that Nvidia has support for my card with NVDEC.</p>
  
  <p>I am running Windows 10 64 bits with i7 4790 and GTX 1080</p>