Hey All, I noticed that ffmpeg always seems to generate a SIDX box when it's not really required for Audio Only content.
Example command: ffmpeg -i atmosTest.mp4 -codec copy -hls_time 0.993 -hls_segment_type fmp4 -hls_flags single_file -hls_playlist_type vod atmosTestffmpeg.m3u8 ffmpeg version N-92272-g0e9c01f Copyright (c) 2000-2018 the FFmpeg developers built with Apple LLVM version 10.0.0 (clang-1000.11.45.2) configuration: --prefix=/Users/ronakp/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/Users/ronakp/ffmpeg_build/include --extra-ldflags=-L/Users/ronakp/ffmpeg_build/lib --extra-libs=-lpthread --extra-libs=-lm --bindir=/Users/ronakp/bin --enable-libfdk_aac --enable-libmp3lame --enable-libopus --enable-nonfree libavutil 56. 20.100 / 56. 20.100 libavcodec 58. 34.100 / 58. 34.100 libavformat 58. 19.102 / 58. 19.102 libavdevice 58. 4.106 / 58. 4.106 libavfilter 7. 38.100 / 7. 38.100 libswscale 5. 2.100 / 5. 2.100 libswresample 3. 2.100 / 3. 2.100 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'atmosTest.mp4': Metadata: major_brand : mp42 minor_version : 1 compatible_brands: mp42dby1isom creation_time : 2018-09-07T19:17:49.000000Z Duration: 00:02:40.80, start: 0.000000, bitrate: 769 kb/s Stream #0:0(und): Audio: eac3 (ec-3 / 0x332D6365), 48000 Hz, 5.1(side), fltp, 768 kb/s (default) Metadata: creation_time : 2018-09-07T19:17:49.000000Z handler_name : sound handler Side data: audio service type: main [hls @ 0x7fbfc4825c00] Opening 'atmosTestffmpeg.m4s' for writing [mp4 @ 0x7fbfc4827600] track 0: codec frame size is not set Output #0, hls, to 'atmosTestffmpeg.m3u8': Metadata: major_brand : mp42 minor_version : 1 compatible_brands: mp42dby1isom encoder : Lavf58.19.102 Stream #0:0(und): Audio: eac3 (ec-3 / 0x332D6365), 48000 Hz, 5.1(side), fltp, 768 kb/s (default) Metadata: creation_time : 2018-09-07T19:17:49.000000Z handler_name : sound handler Side data: audio service type: main Stream mapping: Stream #0:0 -> #0:0 (copy) Press [q] to stop, [?] for help size=N/A time=00:02:40.76 bitrate=N/A speed= 397x video:0kB audio:15075kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown When you look at the generated .m4s file, you will see ftyp, moov, followed by a collection of sidx, moof and mdat atoms. However, when I run a similar command using Apple's Tooling: a45e60e46a79:Dolby ronakp$ mediafilesegmenter -a -r -s atmosTest.ec3 Nov 12 2018 11:58:52.713: ISO fragmented mode, forcing segments to start with I-Frame Nov 12 2018 11:58:52.714: Processing file /Users/ronakp/Desktop/Dolby/atmosTest.ec3 Nov 12 2018 11:58:52.743: Wrote 0 to 578 to main.mp4 Nov 12 2018 11:58:52.748: Wrote 578 to 959266 to main.mp4 Nov 12 2018 11:58:52.749: segment bitrate 768.18 kbits/sec is new max Nov 12 2018 11:58:52.756: Wrote 959266 to 1917954 to main.mp4 Nov 12 2018 11:58:52.763: Wrote 1917954 to 2876642 to main.mp4 Nov 12 2018 11:58:52.772: Wrote 2876642 to 3835330 to main.mp4 Nov 12 2018 11:58:52.777: Wrote 3835330 to 4794018 to main.mp4 Nov 12 2018 11:58:52.784: Wrote 4794018 to 5752706 to main.mp4 Nov 12 2018 11:58:52.793: Wrote 5752706 to 6711394 to main.mp4 Nov 12 2018 11:58:52.800: Wrote 6711394 to 7670082 to main.mp4 Nov 12 2018 11:58:52.880: Wrote 7670082 to 8628770 to main.mp4 Nov 12 2018 11:58:52.924: Wrote 8628770 to 9587458 to main.mp4 Nov 12 2018 11:58:52.966: Wrote 9587458 to 10546146 to main.mp4 Nov 12 2018 11:58:52.973: Wrote 10546146 to 11504834 to main.mp4 Nov 12 2018 11:58:53.017: Wrote 11504834 to 12463522 to main.mp4 Nov 12 2018 11:58:53.060: Wrote 12463522 to 13422210 to main.mp4 Nov 12 2018 11:58:53.102: Wrote 13422210 to 14380898 to main.mp4 Nov 12 2018 11:58:53.147: Wrote 14380898 to 15339586 to main.mp4 Nov 12 2018 11:58:53.147: Wrote 15339586 to 15441066 to main.mp4 Nov 12 2018 11:58:53.147: segment bitrate 768.24 kbits/sec is new max Nov 12 2018 11:58:53.147: Unknown video dynamic range value 0 Nov 12 2018 11:58:53.147: average bit rate is 768.21 kbits/sec - max file bit rate is 768.24 kbits/sec It generates a file without any SIDX atoms; only ftyp, moov & a collection of moof & mdat atoms. Why does ffmpeg do this? How hard would it be to remove this behavior from ffmpeg? Thanks, Ronak _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".