[mythtv-commits] Ticket #12047: mythplayer picks the wrong fps for 1080i matroska, degrading to 1xHW deint

[MythTV]

#12047: mythplayer picks the wrong fps for 1080i matroska, degrading to 1xHW deint
-----------------------------------------+---------------------------------
     Reporter:  angela.schmid@…          |      Owner:
         Type:  Patch - Bug Fix          |     Status:  new
     Priority:  minor                    |  Milestone:  unknown
    Component:  MythTV - Video Playback  |    Version:  Master Head
     Severity:  high                     |   Keywords:  deinterlace mkv
Ticket locked:  0                        |  1080i
-----------------------------------------+---------------------------------
 mythplayer chooses to use the avg_fps (50) instead of the codec_fps (25)
 for 1080i matroska movies, therefor mythplayer decides to degrade
 deinterlacing to max 1xHW.

 The problem is most clearly with a movie with extreme horizontal panning.
 I have a movie which I want to archive in mkv (lossless_cut) with a view
 on a large Chinese dragon wall.

 {{{
 Video
 ID                                       : 1
 Format                                   : AVC
 Format/Info                              : Advanced Video Codec
 Format profile                           : High at L4.0
 Format settings, CABAC                   : Yes
 Format settings, ReFrames                : 4 frames
 Format settings, GOP                     : M=4, N=28
 Codec ID                                 : V_MPEG4/ISO/AVC
 Bit rate                                 : 2 884 Kbps
 Width                                    : 1 920 pixels
 Height                                   : 1 080 pixels
 Display aspect ratio                     : 16:9
 Frame rate mode                          : Variable
 Original frame rate                      : 25.000 fps
 Standard                                 : Component
 Color space                              : YUV
 Chroma subsampling                       : 4:2:0
 Bit depth                                : 8 bits
 Scan type                                : Interlaced
 Scan order                               : Bottom Field First
 }}}

 {{{
 CoreContext avformatdecoder.cpp:1247 (normalized_fps) - AFD: Selected FPS
 is 50 (avg 50 codec 25 container 1000 estimated 50)
 }}}

 Setting primary deinterlacing option (2xHW):
 {{{
 CoreContext videodisplayprofile.cpp:354 (GetFilteredDeint) - VDP:
 GetFilteredDeint() : vdpau -> 'vdpaubasicdoublerate'
 }}}

 Degrade to fallback deinterlacing option (max 1xHW):

 {{{
 CoreContext mythplayer.cpp:2384 (VideoStart) - Player(0): Video sync
 method can't support double framerate (refresh rate too low for 2x deint)
 CoreContext videodisplayprofile.cpp:354 (GetFilteredDeint) - VDP:
 GetFilteredDeint(vdpauadvanced) : vdpau -> 'vdpauadvanced'
 }}}

 Mythplayer should use the codec_fps, which is correct for 1080i.

 The following dirty patch fixes the problem:
 {{{
 diff --git a/mythtv/libs/libmythtv/avformatdecoder.cpp
 b/mythtv/libs/libmythtv/avformatdecoder.cpp
 index 3a42b40..6698484 100644
 --- a/mythtv/libs/libmythtv/avformatdecoder.cpp
 +++ b/mythtv/libs/libmythtv/avformatdecoder.cpp
 @@ -1221,7 +1221,11 @@ float AvFormatDecoder::normalized_fps(AVStream
 *stream, AVCodecContext *enc)

      // matroska demuxer sets the default_duration to avg_frame_rate
      // mov,mp4,m4a,3gp,3g2,mj2 demuxer sets avg_frame_rate
 -    if ((QString(ic->iformat->name).contains("matroska") ||
 +    if ((QString(ic->iformat->name).contains("matroska")) &&
 +        container_fps < 121.0f && container_fps > 3.0f)
 +        fps = container_fps;
 +    else
 +    if ((QString(ic->iformat->name).contains("xmatroska") ||
          QString(ic->iformat->name).contains("mov")) &&
          avg_fps < 121.0f && avg_fps > 3.0f)
          fps = avg_fps;
 }}}

--
Ticket URL: <https://code.mythtv.org/trac/ticket/12047>
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