Using vidstab on 1080p50 results as follows:
 frame_rate_num="25" in <profile>
Kdenlive cannot load this mlt because it's different to the p50 project file.
Manual editing to frame_rate_num="50" let's kdenlive load this file but it is unusable (half length and vidstab looks horrible because of the 25/50 fps mismatch)
See full mlt file below and details about my source file.


Reproducible: Always




<?xml version="1.0" encoding="utf-8"?>
<mlt LC_NUMERIC="de_DE.UTF-8" version="6.1.0" root="/data/data_workplace_chr/transcode.tmp" title="Stabilised">
  <profile description="automatic" width="1920" height="1080" progressive="1" sample_aspect_num="1" sample_aspect_den="1" display_aspect_num="1920" display_aspect_den="1080" frame_rate_num="25" frame_rate_den="1" colorspace="709"/>
  <producer id="producer0" in="0" out="708">
    <property name="length">709</property>
    <property name="eof">pause</property>
    <property name="resource">/data/data_workplace_chr/Projects Video Cut/2016-04-24_Kommunion_50p_kdenlive/2016-04-24_Kommunion_50p/Cam_Stark_Post-ProRes_p50_PCM/2016-04-23_10-41-06_PHDCSD707_00014_Post-ProRes_p50_PCM.mov</property>
    <property name="meta.media.nb_streams">2</property>
    <property name="meta.media.0.stream.type">video</property>
    <property name="meta.media.0.stream.frame_rate">50</property>
    <property name="meta.media.0.stream.sample_aspect_ratio">0</property>
    <property name="meta.media.0.codec.width">1920</property>
    <property name="meta.media.0.codec.height">1080</property>
    <property name="meta.media.0.codec.rotate">0</property>
    <property name="meta.media.0.codec.frame_rate">12800</property>
    <property name="meta.media.0.codec.pix_fmt">yuv422p10le</property>
    <property name="meta.media.0.codec.sample_aspect_ratio">0</property>
    <property name="meta.media.0.codec.colorspace">709</property>
    <property name="meta.media.0.codec.name">prores</property>
    <property name="meta.media.0.codec.long_name">ProRes</property>
    <property name="meta.media.0.codec.bit_rate">219195575</property>
    <property name="meta.attr.0.stream.language.markup">eng</property>
    <property name="meta.attr.0.stream.handler_name.markup">DataHandler</property>
    <property name="meta.attr.0.stream.encoder.markup">Lavc57.24.102 prores_ks</property>
    <property name="meta.media.1.stream.type">audio</property>
    <property name="meta.media.1.codec.sample_fmt">s16</property>
    <property name="meta.media.1.codec.sample_rate">48000</property>
    <property name="meta.media.1.codec.channels">2</property>
    <property name="meta.media.1.codec.name">pcm_s16le</property>
    <property name="meta.media.1.codec.long_name">PCM signed 16-bit little-endian</property>
    <property name="meta.media.1.codec.bit_rate">1536000</property>
    <property name="meta.attr.1.stream.language.markup">eng</property>
    <property name="meta.attr.1.stream.handler_name.markup">DataHandler</property>
    <property name="meta.attr.major_brand.markup">qt  </property>
    <property name="meta.attr.minor_version.markup">512</property>
    <property name="meta.attr.compatible_brands.markup">qt  </property>
    <property name="meta.attr.encoder.markup">Lavf57.25.100</property>
    <property name="seekable">1</property>
    <property name="meta.media.sample_aspect_num">1</property>
    <property name="meta.media.sample_aspect_den">1</property>
    <property name="aspect_ratio">1</property>
    <property name="audio_index">1</property>
    <property name="video_index">0</property>
    <property name="mute_on_pause">1</property>
    <property name="mlt_service">avformat</property>
    <property name="meta.media.frame_rate_num">50</property>
    <property name="meta.media.frame_rate_den">1</property>
    <property name="meta.media.colorspace">709</property>
    <property name="meta.media.color_trc">2</property>
    <property name="meta.media.width">1920</property>
    <property name="meta.media.height">1080</property>
    <property name="meta.media.top_field_first">0</property>
    <property name="meta.media.progressive">1</property>
    <filter id="filter0">
      <property name="filename">/data/data_workplace_chr/Projects Video Cut/2016-04-24_Kommunion_50p_kdenlive/2016-04-24_Kommunion_50p/Cam_Stark_Post-ProRes_p50_PCM/2016-04-23_10-41-06_PHDCSD707_00014_Post-ProRes_p50_PCM.mov.mlt.trf</property>
      <property name="shakiness">4</property>
      <property name="accuracy">8</property>
      <property name="stepsize">6</property>
      <property name="algo">1</property>
      <property name="mincontrast">0.3</property>
      <property name="show">0</property>
      <property name="tripod">0</property>
      <property name="smoothing">10</property>
      <property name="maxshift">-1</property>
      <property name="maxangle">-1</property>
      <property name="crop">1</property>
      <property name="invert">0</property>
      <property name="relative">1</property>
      <property name="zoom">0</property>
      <property name="optzoom">1</property>
      <property name="zoomspeed">0.25</property>
      <property name="reload">0</property>
      <property name="vid.stab.version">v0.98 (2014-01-04)</property>
      <property name="mlt_service">vidstab</property>
      <property name="sharpen">0.8</property>
      <property name="results">/data/data_workplace_chr/Projects Video Cut/2016-04-24_Kommunion_50p_kdenlive/2016-04-24_Kommunion_50p/Cam_Stark_Post-ProRes_p50_PCM/2016-04-23_10-41-06_PHDCSD707_00014_Post-ProRes_p50_PCM.mov.mlt.trf</property>
    </filter>
  </producer>
  <playlist id="playlist0">
    <entry producer="producer0" in="0" out="708"/>
  </playlist>
  <tractor id="tractor0" title="Stabilised" global_feed="1" in="0" out="708">
    <track producer="playlist0"/>
  </tractor>
</mlt>


General
Complete name                            : /data/data_workplace_chr/Projects Video Cut/2016-04-24_Kommunion_50p_kdenlive/2016-04-24_Kommunion_50p/Cam_Stark_Post-ProRes_p50_PCM/2016-04-23_10-41-06_PHDCSD707_00014_Post-ProRes_p50_PCM.mov
Format                                   : MPEG-4
Format profile                           : QuickTime
Codec ID                                 : qt  
File size                                : 745 MiB
Duration                                 : 28s 352ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 220 Mbps
Writing application                      : Lavf57.25.100

Video
ID                                       : 1
Format                                   : ProRes
Format version                           : Version 0
Format profile                           : 422
Codec ID                                 : apcn
Duration                                 : 28s 320ms
Bit rate mode                            : Variable
Bit rate                                 : 219 Mbps
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 50.000 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:2
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 2.114
Stream size                              : 740 MiB (99%)
Writing library                          : ap10
Language                                 : English

Audio
ID                                       : 2
Format                                   : PCM
Format settings, Endianness              : Little
Format settings, Sign                    : Signed
Codec ID                                 : sowt
Duration                                 : 28s 352ms
Bit rate mode                            : Constant
Bit rate                                 : 1 536 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 KHz
Bit depth                                : 16 bits
Stream size                              : 5.19 MiB (1%)
Language                                 : English