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La conservation du net art au musée. Les stratégies à l’œuvre
26 mai 2011
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Sur d’autres sites (10931)
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ffmpeg ignores seg_duration with svt-av1
25 décembre 2022, par Asav MaliI'm trying to convert a mp4 file containing a HEVC HDR10 stream to AV1 using SVT-AV1 with ffmpeg. For some reason the seg_duration parameter gets ignored :




/usr/bin/ffmpeg -i "/tmp/VODProcessing/testclip.mp4" -map 0:0 -c:v
libsvtav1 -b:v 1048576 -maxrate:v 1101004 -bufsize 4194304 -vf
zscale=width=640:height=480 -svtav1-params
"tile-columns=0:tile-rows=0:scd=0:color-primaries=9:transfer-characteristics=16:matrix-coefficients=9:input-depth=10:fast-decode=1:mastering-display=G(0.265,0.69)B(0.15,0.06)R(0.68,0.32)WP(0.3127,0.329)L(4000.0,0.005):content-light=368,226:enable-hdr=1:color-range=1"
-pix_fmt yuv420p10le -color_trc smpte2084 -color_primaries bt2020 -colorspace bt2020nc -chroma_sample_location:v topleft -color_range:v pc -max_muxing_queue_size 1024 -preset 7 -bf 0 -force_key_frames
"expr:gte(t,n_forced*2)" -keyint_min 48 -use_timeline 1 -use_template
1 -map_metadata -1 -map_chapters -1 -f hls -seg_duration 4 -hls_time 4
-streaming 1 -hls_list_size 0 -hls_segment_filename "/tmp/VODProcessing/output/testclip/v-av01-480p-av01.0.12M.10_PQ/f-%04d.m4s"
-hls_fmp4_init_filename "init-v-av01-480p-av01.0.12M.10_PQ.m4s" -hls_segment_type fmp4 -hls_playlist_type vod -movflags frag_keyframe+frag_every_frame+write_colr+prefer_icc+skip_trailer+faststart
-hls_flags independent_segments -strict experimental "/tmp/VODProcessing/output/testclip/v-av01-480p-av01.0.12M.10_PQ/master.m3u8"




Using a similar command and transcoding HEVC to HEVC works as expected and the segment duration is fine. Does this make any sense ? Checking the generated master.m3u8 file always gives me this for AV1 :


#EXTM3U
#EXT-X-VERSION:7
#EXT-X-TARGETDURATION:7
#EXT-X-MEDIA-SEQUENCE:0
#EXT-X-PLAYLIST-TYPE:VOD
#EXT-X-INDEPENDENT-SEGMENTS
#EXT-X-MAP:URI="init-v-av01-480p-av01.0.12M.10_PQ.m4s"
#EXTINF:6.715042,
f-0000.m4s
#EXTINF:6.715042,
f-0001.m4s
#EXTINF:6.715042,
f-0002.m4s
#EXTINF:6.715042,
f-0003.m4s
#EXTINF:6.715042,
f-0004.m4s
#EXTINF:6.715042,
f-0005.m4s
#EXTINF:6.715042,
f-0006.m4s
#EXTINF:6.715042,
f-0007.m4s
#EXTINF:6.715042,
f-0008.m4s
#EXTINF:6.715042,
f-0009.m4s
#EXTINF:6.715042,
f-0010.m4s
#EXTINF:6.715042,
f-0011.m4s
#EXTINF:6.715042,
f-0012.m4s
#EXTINF:6.715042,
f-0013.m4s
#EXTINF:6.715042,
f-0014.m4s
#EXTINF:6.715042,
f-0015.m4s
#EXTINF:0.583917,
f-0016.m4s
#EXT-X-ENDLIST



As you can see, the segments are not 4 seconds long as defined in my command, they are 6.715042 seconds long, why that ???


Thanks in advance


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FFmpeg : how to stream multiple http outputs
25 octobre 2022, par Caner DemirI'm assigned to search for a solution to stream more than one http output in ffmpeg. I tried the code below which uses pipe, but only the last output works, other ones don't work. The solutions I tried with tee muxer also couldn't work. Any idea how can I do that ?


ffmpeg -re -i sample1.mp3 -i sample2.mp3 -filter_complex amix=inputs=2 -f mp3 pipe:1 | ffmpeg -f mp3 -re -i pipe:0 -c copy -listen 1 -f mp3 http://127.0.0.1:4000 -c copy -listen 1 -f mp3 http://127.0.0.1:4010



The code I tried with tee muxer is below :


ffmpeg -re -i sample1.mp3 -i sample2.mp3 -filter_complex amix=inputs=2 -c:a mp3 -f tee "[listen=1:f=mp3]http://127.0.0.1:4000|[listen=1:f=mp3]http://127.0.0.1:4010"



edit : shared the log with code.


ffmpeg -loglevel debug -hide_banner -re -i sample1.mp3 -filter_complex asplit=2 -c:a mp3 -listen 1 -f mp3 http://127.0.0.1:4000 -c:a mp3 -listen 1 -f mp3 http://127.0.0.1:4010
Splitting the commandline.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument 'debug'.
Reading option '-hide_banner' ... matched as option 'hide_banner' (do not show program banner) with argument '1'.
Reading option '-re' ... matched as option 're' (read input at native frame rate; equivalent to -readrate 1) with argument '1'.
Reading option '-i' ... matched as input url with argument 'sample1.mp3'.
Reading option '-filter_complex' ... matched as option 'filter_complex' (create a complex filtergraph) with argument 'asplit=2'.
Reading option '-c:a' ... matched as option 'c' (codec name) with argument 'mp3'.
Reading option '-listen' ... matched as AVOption 'listen' with argument '1'.
Reading option '-f' ... matched as option 'f' (force format) with argument 'mp3'.
Reading option 'http://127.0.0.1:4000' ... matched as output url.
Reading option '-c:a' ... matched as option 'c' (codec name) with argument 'mp3'.
Reading option '-listen' ... matched as AVOption 'listen' with argument '1'.
Reading option '-f' ... matched as option 'f' (force format) with argument 'mp3'.
Reading option 'http://127.0.0.1:4010' ... matched as output url.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option loglevel (set logging level) with argument debug.
Applying option hide_banner (do not show program banner) with argument 1.
Applying option filter_complex (create a complex filtergraph) with argument asplit=2.
Successfully parsed a group of options.
Parsing a group of options: input url sample1.mp3.
Applying option re (read input at native frame rate; equivalent to -readrate 1) with argument 1.
Successfully parsed a group of options.
Opening an input file: sample1.mp3.
[NULL @ 00000216ab345b80] Opening 'sample1.mp3' for reading
[file @ 00000216ab346180] Setting default whitelist 'file,crypto,data'
[mp3 @ 00000216ab345b80] Format mp3 probed with size=4096 and score=51
id3v2 ver:4 flags:00 len:134
[mp3 @ 00000216ab345b80] pad 576 576
[mp3 @ 00000216ab345b80] Skipping 0 bytes of junk at 561.
[mp3 @ 00000216ab345b80] Before avformat_find_stream_info() pos: 561 bytes read:32768 seeks:0 nb_streams:1
[mp3 @ 00000216ab345b80] demuxer injecting skip 1105 / discard 0
[mp3float @ 00000216ab34f3c0] skip 1105 / discard 0 samples due to side data
[mp3float @ 00000216ab34f3c0] skip 1105/1152 samples
[mp3 @ 00000216ab345b80] All info found
[mp3 @ 00000216ab345b80] After avformat_find_stream_info() pos: 22065 bytes read:32768 seeks:0 frames:50
Input #0, mp3, from 'sample1.mp3':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2mp41
 encoder : Lavf58.45.100
 Duration: 00:12:58.48, start: 0.025057, bitrate: 128 kb/s
 Stream #0:0, 50, 1/14112000: Audio: mp3, 44100 Hz, stereo, fltp, 128 kb/s
 Metadata:
 encoder : Lavc58.91
Successfully opened the file.
[Parsed_asplit_0 @ 00000216ab34fc80] Setting 'outputs' to value '2'
Parsing a group of options: output url http://127.0.0.1:4000.
Applying option c:a (codec name) with argument mp3.
Applying option f (force format) with argument mp3.
Successfully parsed a group of options.
Opening an output file: http://127.0.0.1:4000.
Matched encoder 'libmp3lame' for codec 'mp3'.
 Last message repeated 1 times
[http @ 00000216ab44d980] Setting default whitelist 'http,https,tls,rtp,tcp,udp,crypto,httpproxy,data'



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How to transcode 4K HDR using libx265 or libsvtav1 with ffmpeg ?
28 octobre 2022, par Asav MaliIm currently trying to transcode a mp4 file containing a HEVC 10 Bit HDR stream with proper grading information to HLS (fragmented mp4 aka fmp4) in two different codecs, HEVC and AV1. The problem is that the x265 encoder pops the following message while transcoding starts :


Output #0, hls, to '/tmp/output/testclip/v-hevc-2160p-hvc1.2.4.L150.B0/master.m3u8':
 Metadata:
 encoder : Lavf59.27.100
 Stream #0:0: Video: hevc (hvc1 / 0x31637668), yuv420p10le(tv, bt2020nc/bt2020/smpte2084, progressive), 3840x1600 [SAR 1:1 DAR 12:5], q=2-31, 7864 kb/s, 23.98 fps, 24k tbn (default)
 Metadata:
 encoder : Lavc59.37.100 libx265
 Side data:
 cpb: bitrate max/min/avg: 8257000/0/0 buffer size: 31457000 vbv_delay: N/A
 Mastering Display Metadata, has_primaries:1 has_luminance:1 r(0.6800,0.3200) g(0.2650,0.6900) b(0.1500 0.0600) wp(0.3127, 0.3290) min_luminance=0.005000, max_luminance=4000.000000
 Content Light Level Metadata, MaxCLL=368, MaxFALL=226
x265 [warning]: unable to parse mastering display color volume infoed= 0x 
x265 [warning]: unable to parse mastering display color volume infoeed=0.758x 
x265 [warning]: unable to parse mastering display color volume infoeed=1.06x 



Why is the message "unable to parse mastering display color volume info" coming up if I explicitly define the grading info using the following command ? :


/usr/bin/ffmpeg -i "/tmp/testclip.m4v" -map 0:0 -c:v libx265 -b:v 7864320 -maxrate:v 8257536 -bufsize 31457280 -vf zscale=width=3840:height=1600 -x265-params colorprim=bt2020:transfer=smpte-2084:colormatrix=bt2020nc:master-display="G(13250.0,34500.0)B(7500.0,3000.0)R(34000.0,16000.0)WP(15635.0,16450.0)L(40000000.0,50.0):max-cll="368.0,226.0"" -pix_fmt yuv420p10le -profile:v main10 -bf 0 -crf 16 -preset fast -keyint_min 48 -g 48 -sc_threshold 0 -use_timeline 1 -use_template 1 -seg_duration 6 -tune fastdecode -vtag hvc1 -map_metadata -1 -map_chapters -1 -f hls -hls_time 6 -streaming 1 -hls_list_size 0 -hls_segment_filename "/tmp/output/testclip/v-hevc-2160p-hvc1.2.4.L150.B0/f-%04d.m4s" -hls_fmp4_init_filename "init-v-hevc-2160p-hvc1.2.4.L150.B0.m4s" -hls_segment_type fmp4 -movflags frag_every_frame+delay_moov+skip_trailer+faststart -hls_flags independent_segments "/tmp/output/testclip/v-hevc-2160p-hvc1.2.4.L150.B0/master.m3u8"



No matter if I define the "master-display" or not, the image stays the same according to the colors, If I don't define "master-display" I dont get the annoying message form the x265 encoder for some reason. Can somebody give an answer how the x265 encoder works with ffmpeg and HDR ?


Besides the HEVC stream, I also create a AV1 stream using libsvtav1. Here I'm using a quite similar command, but the image looks differently compared against the HEVC version, much colder, why that ? I define the grading information explicitly for the libsvtav1 encoder the same way as I do it for x265 using mastering-display...? :


/usr/bin/ffmpeg -i "/tmp/testclip.m4v" -map 0:0 -c:v libsvtav1 -b:v 6291456 -maxrate:v 6606028 -bufsize 25165824 -vf zscale=width=3840:height=1600 -svtav1-params input-depth=10:fast-decode=1:color-primaries=9:transfer-characteristics=16:matrix-coefficients=9:mastering-display="G(0.265,0.69)B(0.15,0.06)R(0.68,0.32)WP(0.3127,0.329)L(4000.0,0.005):content-light="368.0,226.0"":enable-hdr=1 -pix_fmt yuv420p10le -max_muxing_queue_size 1024 -profile:v main -preset 7 -crf 20 -keyint_min 48 -g 48 -use_timeline 1 -use_template 1 -seg_duration 6 -strict experimental -map_metadata -1 -map_chapters -1 -f hls -hls_time 6 -streaming 1 -hls_list_size 0 -hls_segment_filename "/tmp/output/testclip/v-av01-2160p-av01.0.12H.10/f-%04d.m4s" -hls_fmp4_init_filename "init-v-av01-2160p-av01.0.12H.10.m4s" -hls_segment_type fmp4 -movflags frag_every_frame+delay_moov+skip_trailer+faststart -hls_flags independent_segments "/tmp/output/testclip/v-av01-2160p-av01.0.12H.10/master.m3u8"



I would expect that grading information will get placed properly with both encoders.


Thanks in advance.