On 2021-02-26 15:40, Mark Filipak (ffmpeg) wrote:
'ffmpeg -i input.mkv -vf "settb=expr=1/360000,showinfo" -codec:a copy
-codec:s copy -dn output.mkv'
partial output shown below.
input.mkv is 30.1.001fps constant frame rate. I expected deltaPTS to
be 12012.
Look at the 1st frame:
(0.033s/frame)*(360000ticks/s) = 11880ticks/frame,
instead of:
((1.001/30)s/frame)*(360000ticks/s) = 12012ticks/frame.
Why is that? It destroys the resolution improvement of the
1/(360000Hz) time base.
[Parsed_showinfo_1 @ 00000211128f2340] n: 1 pts: 11880
pts_time:0.033 pos: 10052 fmt:yuv420p sar:32/27 s:240x236 i:P
iskey:0 type:B checksum:3CF10BFE plane_checksum:[64208370 00B13226
C5775659] mean:[25 126 131] stdev:[12.8 6.1 1.6]
[Parsed_showinfo_1 @ 00000211128f2340] n: 2 pts: 24120
pts_time:0.067 pos: 9213 fmt:yuv420p sar:32/27 s:240x236 i:P
iskey:0 type:B checksum:23A8A65F plane_checksum:[90DC2AA6 37E908C8
779972F1] mean:[27 125 132] stdev:[14.8 7.1 1.9]
[Parsed_showinfo_1 @ 00000211128f2340] n: 3 pts: 36000
pts_time:0.1 pos: 11086 fmt:yuv420p sar:32/27 s:240x236 i:P
iskey:0 type:B checksum:1CDF7A80 plane_checksum:[089DE80E C537F4C0
8C4E9D94] mean:[29 125 132] stdev:[15.2 6.6 2.3]
…[elided for brevity]…
[Parsed_showinfo_1 @ 00000211128f2340] n: 28 pts: 336240
pts_time:0.934 pos: 45167 fmt:yuv420p sar:32/27 s:240x236 i:P
iskey:0 type:B checksum:8D724A43 plane_checksum:[CD1CE198 DC377EA5
3D51E9E8] mean:[70 113 148] stdev:[46.3 11.6 11.5]
[Parsed_showinfo_1 @ 00000211128f2340] n: 29 pts: 348480
pts_time:0.968 pos: 40163 fmt:yuv420p sar:32/27 s:240x236 i:P
iskey:0 type:P checksum:8F6C0D42 plane_checksum:[385DA9F1 7EA37D5A
AD78E5D9] mean:[70 113 148] stdev:[46.6 11.6 11.5]
[Parsed_showinfo_1 @ 00000211128f2340] n: 30 pts: 360360
pts_time:1.001 pos: 50467 fmt:yuv420p sar:32/27 s:240x236 i:P
iskey:0 type:B checksum:B511B7BA plane_checksum:[9C9A49A0 B1D583BA
FA0EEA51] mean:[70 113 148] stdev:[46.5 11.4 11.6]
Does input1.mkv in fact have a constant frame rate of 24/1.001
frames/second? If you remove the settb video filter, and just use
showinfo, what pts and pts_time values does it report for the first 30
frames of input1.mkv?
It's important that input1.mkv have a constant Presentation Timestamp
(PTS) increment, and a constant timebase which is a multiple of 24/1.001
ticks/second. Obviously.
—Jim DeLaHunt
_______________________________________________
ffmpeg-user mailing list
ffmpeg-user@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-user
To unsubscribe, visit link above, or email
ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
