help video jerky conversion

[whs912km]

hi there, i have some old video file (video only, already detach audio file) but video is jerky (or choppy)
already tried to re-encoding with ffmpeg with this simply command:

ffmpeg -i video.mp4 -c:v libx264 -crf 23 -preset:v fast -y video_2.mp4

but no luck. video is always with same problem (jerky)
someone have right suggestion about this ?
here MediaInfo video details:

General
Complete name                            : C:\9435843.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom (isom/iso2/avc1/mp41)
File size                                : 41.9 MiB
Duration                                 : 11 min 34 s
Overall bit rate                         : 506 kb/s
Frame rate                               : 7.868 FPS
Writing application                      : Lavf60.18.100

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L3.1
Format settings                          : CABAC / 4 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 4 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 11 min 34 s
Source duration                          : 18 s 108 ms
Bit rate                                 : 505 kb/s
Width                                    : 586 pixels
Height                                   : 888 pixels
Display aspect ratio                     : 0.660
Frame rate mode                          : Constant
Frame rate                               : 7.868 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.123
Stream size                              : 41.8 MiB (100%)
Source stream size                       : 41.8 MiB (100%)
Writing library                          : x264 core 152 r2851 ba24899
Encoding settings                        : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=6 / lookahead_threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=7 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=23.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
mdhd_Duration                            : 694481
Codec configuration box                  : avcC

[davexnet]

Is that the mediainfo from your source? Or the encode?
It's only 7 frames per second, that might explain why it's jerky

Frame rate         : 7.868 FPS

[whs912km]

are details of the original video

and yes, i agree, maybe issue is due to low frame/second. and so how to enhance video ?

[lomero]

try this one:

ffmpeg -i in.mp4 -filter:v "setpts=PTS/1.5,fps=25" out.mp4

this command increase play speed to 1.5 and FPS to 25