Open Bossett opened 6 days ago
Some invesigation - https://bsky.app/profile/bossett.social/post/3l3y5yjp6v22q plays on the phone.
The only difference is chroma subsampling - the new image is 4:2:0 and the original is 4:4:4
mediainfo of working file:
General
Format : MPEG-4
Format profile : Base Media
Codec ID : isom (isom/iso2/avc1/mp41)
File size : 3.22 MiB
Duration : 59 s 0 ms
Overall bit rate : 457 kb/s
Frame rate : 120.000 FPS
Writing application : Lavf58.64.100
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L5.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference : 4 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 59 s 0 ms
Bit rate : 448 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 120.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.002
Stream size : 3.15 MiB (98%)
Writing library : x264 core 161 r3027 4121277
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=34 / lookahead_threads=5 / 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
Codec configuration box : avcC
working file: https://github.com/user-attachments/assets/5dceff32-53f5-4d08-a303-af45ab1d3c62
generated with: ffmpeg -f lavfi -i testsrc=duration=59:size=1920x1080:rate=120 -pix_fmt yuv420p yuv420p.mp4
suggest the fix here is just to force 4:2:0 in the processing step to maximise compatibility
https://bsky.app/profile/bossett.social/post/3l3zhoecfp22q - appears now fixed, this is ffmpeg -f lavfi -i testsrc=duration=58:size=1920x1080:rate=120 testsrc5.mp4
and working on iOS
Describe the bug
See https://bsky.app/profile/bossett.social/post/3l3wru4mlxy2j. The ffmpeg testrc pattern in 1920x1080 @ 120fps causes a number of playback issues.
To Reproduce
Generate a test file using ffmpeg mp4 defaults:
ffmpeg -f lavfi -i testsrc=duration=59:size=1920x1080:rate=120 testsrc.mp4
Upload file, and view on mobile (and some other platforms)
Expected behavior
No errors
Screenshots
(others in thread)
Details
Additional context
https://bsky.app/profile/bossett.social/post/3l3wssuiaju2i - also resizes slightly when hitting play on web, where it works
https://github.com/user-attachments/assets/a42e6f6d-c356-41a9-a117-1c945526e345 is the video original and media info: