"Music Box Russia" channel over satellite transmits in HEVC 1920x1080 25fps interlaced - and after recording VLC recognizes file as 50 fps, and resolution 1920x540 - half a height. But on satellite tuner the player works fine - it plays a file as 1920x1080 25fps... When we can expect support for HEVC/H.265 interlaced? Here is recorded file (Garry Grey & Eva Miller - wtf). Also - a lot of lost frames in VLC player statistics..
EDIT:
I found some interesting info how in HEVC the interlace video content can be indicated here:
Unlike to H.264/AVC, interlace-dedicated coding in HEVC is not exist:
- No mixed frame-field interaction (like PAFF in H.264/AVC)
- No interlace scanning of transform coefficients
- No correction MVX[1] (or y-component of MV) if current and reference pictures are in different polarity (top-bottom or bottom-top).
However, in HEVC the interlace video content can be indicated (signaled in VPS/SPS and
pic_timingSEI messages the latter are transmitted for every picture in the sequence). Interlace-related setting:
in VPS/SPS set
general_interlaced_source_flag=1andgeneral_progressive_source_flag=0. Indeed, the HEVC standard says:if
general_progressive_source_flagis equal to0andgeneral_interlaced_source_flagis equal to1, the source scan type of the pictures in the CVS should be interpreted as interlaced only.in VPS/SPS set
general_frame_only_constraint_flag=0in SPS VUI set
field_seq_flag=1andframe_field_info_present_flag=1. Notice that if these flags are ON then picture timing SEIs shall be present for each picture.transmission of Picture Timing SEI per picture with the following parameters:
source_scan_type = 0to indicate interlace mode for top field picture signalpict_struct=1and for bottom field picturepict_struct=2
Perhaps it is possible to pass these parameters to ffmpeg/vlc before playing a file?
(Adding as an answer as I can't comment yet.) "This is an authoring problem and not related to VLC. " There may also be an authoring problem but the problem is related to VLC, more specifically to FFMpeg's lack of understanding of interlaced HEVC which affects the multitudes of applications that rely on it. Most programs have not been written for support which is starting to be a noted problem due to ATSC 3.0 broadcasts in the US starting and some are doing so in 1080i HEVC. A station can get around it by 'forcing' the aspect ratio which makes the software incorrectly report it as 1080p by software like Mediainfo and VLC but at least it displays with the correct aspect ratio. https://trac.ffmpeg.org/ticket/5514 https://trac.ffmpeg.org/ticket/4141