Wrong duration of AVC elementary stream after recent changes
MichalFiglarowicz opened this issue · 4 comments
MediaInfo v24.01 reports different Duration and Frame Rate of the AVC (H.264) elementary stream then v22.09. I only noticed it when I use the source which was sliced from the origin video (but not sure if it needed). Here is how I prepared the source:
ffmpeg -y -ss 00:00:05.0 -i big_buck_bunny.mov -t 00:00:10.0 -c:v libx264 -an -vf "fps=30,scale=640:480" -f h264 bunny.h264
So it cut from 5 second to 15 second of source, changes fps to 30 + downsizes image (just for reducing size of the file) and outputs as H.264 elementary stream.
I would expect the duration of such stream to be close to 10 seconds + fps reported as 30.
I noticed different behaviour of MediaInfoLib after commit 5271548
Before that commit I got Duration 10 s 0 ms and FPS 30.000 FPS
General
Complete name : bunny.h264
Format : AVC
Format/Info : Advanced Video Codec
File size : 1.16 MiB
Duration : 10 s 0 ms
Overall bit rate : 970 kb/s
Writing library : x264 core 164 r3108 31e19f9
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=15 / lookahead_threads=2 / 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=25 / 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
Video
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Duration : 10 s 0 ms
Bit rate : 970 kb/s
Width : 640 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate mode : Variable
Frame rate : 30.000 FPS
But after this commit I get Duration 6 s 933 ms and FPS 43.271 FPS
General
Complete name : bunny.h264
Format : AVC
Format/Info : Advanced Video Codec
File size : 1.16 MiB
Duration : 6 s 933 ms
Overall bit rate : 1 399 kb/s
Frame rate : 43.271 FPS
Writing library : x264 core 164 r3108 31e19f9
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=15 / lookahead_threads=2 / 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=25 / 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
Video
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Duration : 6 s 933 ms
Bit rate : 1 399 kb/s
Width : 640 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate mode : Variable
Frame rate : 43.271 FPS
I also noticed that the difference in Duration is highly related with the fps which I use to encode the stream.
Here is an example file - named .mp4 to be able to attach to issue ;-)
bunny_30fps.h264.mp4
generated with
ffmpeg -y -ss 00:00:05.0 -i big_buck_bunny.mov -t 00:00:10.0 -c:v libx264 -an -vf "fps=30,scale=640:480" -f h264 bunny.h264
Not sure if the file can be downloaded. If not please give me a hint how to send the sources in proper way.
It can be downloaded, right click, save video.
Before that commit I got Duration 10 s 0 ms and FPS 30.000 FPS
Well, ffplay cannot recognise any fps in this video and just says 25 fps. Now, this is a mistake, as it appears it has 60 fps data.
[trace_headers @ 000002185997d200] 70 vui_parameters_present_flag 1 = 1
[trace_headers @ 000002185997d200] 71 aspect_ratio_info_present_flag 0 = 0
[trace_headers @ 000002185997d200] 72 overscan_info_present_flag 0 = 0
[trace_headers @ 000002185997d200] 73 video_signal_type_present_flag 0 = 0
[trace_headers @ 000002185997d200] 74 chroma_loc_info_present_flag 0 = 0
[trace_headers @ 000002185997d200] 75 timing_info_present_flag 1 = 1
[trace_headers @ 000002185997d200] 76 num_units_in_tick 00000000000000000000000000000001 = 1
[trace_headers @ 000002185997d200] 108 time_scale 00000000000000000000000000111100 = 60
[trace_headers @ 000002185997d200] 140 fixed_frame_rate_flag 0 = 0
Well, ffplay cannot recognise any fps in this video and just says 25 fps.
Quick test with FFmpeg 4.4.2 and 30 fps are detected:
Stream #0:0: Video: h264 (High), yuv420p(progressive), 320x240, 30 fps, 30 tbr, 1200k tbn, 60 tbc
Issue is in MI, no discussion about that.
Update ffmpeg?
