Replace deprecated code

[nschlia]

Several deprecated settings must be replaced

#if FF_API_TICKS_PER_FRAME
Global AVCodecContext::ticks_per_frame
    decoding: Use AVCodecDescriptor.props & AV_CODEC_PROP_FIELDS
    encoding: Set AVCodecContext.framerate instead

#if FF_API_FRAME_KEY
Global AVFrame::key_frame
    Use AV_FRAME_FLAG_KEY instead 

 #if FF_API_INTERLACED_FRAME
Global AVFrame::top_field_first
    Use AV_FRAME_FLAG_TOP_FIELD_FIRST instead
Global AVFrame::interlaced_frame
    Use AV_FRAME_FLAG_INTERLACED instead 

+#if FF_API_FLAG_TRUNCATED
 /**
  * Input bitstream might be truncated at a random location
  * instead of only at frame boundaries.
+ *
+ * @deprecated use codec parsers for packetizing input
  */
 #define AV_CODEC_FLAG_TRUNCATED       (1 << 16)
+#endif

https://ffmpeg.org/doxygen/trunk/deprecated.html
https://raw.githubusercontent.com/FFmpeg/FFmpeg/master/doc/APIchanges